Sample records for weather variability tides

  1. Weather Variability, Tides, and Barmah Forest Virus Disease in the Gladstone Region, Australia

    PubMed Central

    Naish, Suchithra; Hu, Wenbiao; Nicholls, Neville; Mackenzie, John S.; McMichael, Anthony J.; Dale, Pat; Tong, Shilu

    2006-01-01

    In this study we examined the impact of weather variability and tides on the transmission of Barmah Forest virus (BFV) disease and developed a weather-based forecasting model for BFV disease in the Gladstone region, Australia. We used seasonal autoregressive integrated moving-average (SARIMA) models to determine the contribution of weather variables to BFV transmission after the time-series data of response and explanatory variables were made stationary through seasonal differencing. We obtained data on the monthly counts of BFV cases, weather variables (e.g., mean minimum and maximum temperature, total rainfall, and mean relative humidity), high and low tides, and the population size in the Gladstone region between January 1992 and December 2001 from the Queensland Department of Health, Australian Bureau of Meteorology, Queensland Department of Transport, and Australian Bureau of Statistics, respectively. The SARIMA model shows that the 5-month moving average of minimum temperature (β = 0.15, p-value < 0.001) was statistically significantly and positively associated with BFV disease, whereas high tide in the current month (β = −1.03, p-value = 0.04) was statistically significantly and inversely associated with it. However, no significant association was found for other variables. These results may be applied to forecast the occurrence of BFV disease and to use public health resources in BFV control and prevention. PMID:16675420

  2. Weather variability, tides, and Barmah Forest virus disease in the Gladstone region, Australia.

    PubMed

    Naish, Suchithra; Hu, Wenbiao; Nicholls, Neville; Mackenzie, John S; McMichael, Anthony J; Dale, Pat; Tong, Shilu

    2006-05-01

    In this study we examined the impact of weather variability and tides on the transmission of Barmah Forest virus (BFV) disease and developed a weather-based forecasting model for BFV disease in the Gladstone region, Australia. We used seasonal autoregressive integrated moving-average (SARIMA) models to determine the contribution of weather variables to BFV transmission after the time-series data of response and explanatory variables were made stationary through seasonal differencing. We obtained data on the monthly counts of BFV cases, weather variables (e.g., mean minimum and maximum temperature, total rainfall, and mean relative humidity), high and low tides, and the population size in the Gladstone region between January 1992 and December 2001 from the Queensland Department of Health, Australian Bureau of Meteorology, Queensland Department of Transport, and Australian Bureau of Statistics, respectively. The SARIMA model shows that the 5-month moving average of minimum temperature (b=0.15, p-value<0.001) was statistically significantly and positively associated with BFV disease, whereas high tide in the current month (b=-1.03, p-value=0.04) was statistically significantly and inversely associated with it. However, no significant association was found for other variables. These results may be applied to forecast the occurrence of BFV disease and to use public health resources in BFV control and prevention.

  3. Tides and Decadal Variability

    NASA Technical Reports Server (NTRS)

    Ray, Richard D.

    2003-01-01

    This paper reviews the mechanisms by which oceanic tides and decadal variability in the oceans are connected. We distinguish between variability caused by tides and variability observed in the tides themselves. Both effects have been detected at some level. The most obvious connection with decadal timescales is through the 18.6-year precession of the moon's orbit plane. This precession gives rise to a small tide of the same period and to 18.6-year modulations in the phase and amplitudes of short-period tides. The 18.6-year "node tide" is very small, no more than 2 cm anywhere, and in sea level data it is dominated by the ocean's natural Variability. Some authors have naively attributed climate variations with periods near 19 years directly to the node tide, but the amplitude of the tide is too small for this mechanism to be operative. The more likely explanation (Loder and Garrett, JGR, 83, 1967-70, 1978) is that the 18.6-y modulations in short-period tides, especially h e principal tide M2, cause variations in ocean mixing, which is then observed in temperature and other climatic indicators. Tidally forced variability has also been proposed by some authors, either in response to occasional (and highly predictable) tidal extremes or as a nonlinear low-frequency oscillation caused by interactions between short-period tides. The former mechanism can produce only short-duration events hardly more significant than normal tidal ranges, but the latter mechanism can in principle induce low-frequency oscillations. The most recent proposal of this type is by Keeling and Whorf, who highlight the 1800-year spectral peak discovered by Bond et al. (1997). But the proposal appears contrived and should be considered, in the words of Munk et al. (2002), "as the most likely among unlikely candidates."

  4. Observations and simulations of the ionospheric lunar tide: Seasonal variability

    NASA Astrophysics Data System (ADS)

    Pedatella, N. M.

    2014-07-01

    The seasonal variability of the ionospheric lunar tide is investigated using a combination of Constellation Observing System for Meteorology, Ionosphere, and Climate (COSMIC) observations and thermosphere-ionosphere-mesosphere electrodynamics general circulation model (TIME-GCM) simulations. The present study focuses on the seasonal variability of the lunar tide in the ionosphere and its potential connection to the occurrence of stratosphere sudden warmings (SSWs). COSMIC maximum F region electron density (NmF2) and total electron content observations reveal a primarily annual variation of the ionospheric lunar tide, with maximum amplitudes occurring at low latitudes during December-February. Simulations of the lunar tide climatology in TIME-GCM display a similar annual variability as the COSMIC observations. This leads to the conclusion that the annual variability of the lunar tide in the ionosphere is not solely due to the occurrence of SSWs. Rather, the annual variability of the lunar tide in the ionosphere is generated by the seasonal variability of the lunar tide at E region altitudes. However, compared to the observations, the ionospheric lunar tide annual variability is weaker in the climatological simulations which is attributed to the occurrence of SSWs during the majority of the years included in the observations. Introducing a SSW into the TIME-GCM simulation leads to an additional enhancement of the lunar tide during Northern Hemisphere winter, increasing the lunar tide annual variability and resulting in an annual variability that is more consistent with the observations. The occurrence of SSWs can therefore potentially bias lunar tide climatologies, and it is important to consider these effects in studies of the lunar tide in the atmosphere and ionosphere.

  5. Solar cycle variability of nonmigrating tides in the infrared cooling of the thermosphere

    NASA Astrophysics Data System (ADS)

    Nischal, N.; Oberheide, J.; Mlynczak, M. G.; Marsh, D. R.

    2017-12-01

    Nitric Oxide (NO) at 5.3 μm and Carbon dioxide (CO2) at 15 μm are the major infrared emissions responsible for the radiative cooling of the thermosphere. We study the impact of two important diurnal nonmigrating tides, the DE2 and DE3, on NO and CO2 infrared emissions over a complete solar cycle (2002-2013) by (i) analyzing NO and CO2 cooling rate data from SABER and (ii) photochemical modeling using dynamical tides from a thermospheric empirical tidal model, CTMT. Both observed and modeled results show that the NO cooling rate amplitudes for DE2 and DE3 exhibit strong solar cycle dependence. NO 5.3 μm cooling rate tides are relatively unimportant for the infrared energy budget during solar minimum but important during solar maximum. On the other hand DE2 and DE3 in CO2 show comparatively small variability over a solar cycle. CO2 15 μm cooling rate tides remain, to a large extent, constant between solar minimum and maximum. This different responses by NO and CO2 emissions to the DE2 and DE3 during a solar cycle comes form the fact that the collisional reaction rate for NO is highly sensitive to the temperature comparative to that for CO2. Moreover, the solar cycle variability of these nonmigrating tides in thermospheric infrared emissions shows a clear QBO signals substantiating the impact of tropospheric weather system on the energy budget of the thermosphere. The relative contribution from the individual tidal drivers; temperature, density and advection to the observed DE2 and DE3 tides does not vary much over the course of the solar cycle, and this is true for both NO and CO2 emissions.

  6. Barometric Tides from ECMWF Operational Analyses

    NASA Technical Reports Server (NTRS)

    Ray, R. D.; Ponte, R. M.

    2003-01-01

    The solar diurnal and semidiurnal tidal oscillations in surface pressure are extracted from the the operational analysis product of the European Centre for Medium Range Weather Forecasting (ECMWF). For the semidiurnal tide this involves a special temporal interpolation, following Van den Dool and colleagues. The resulting tides are compared with a ground truth tide dataset, a compilation of well-determined tide estimates deduced from long time series of station barometer measurements. These comparisons show that the ECMWF tides are significantly more accurate than the tides deduced from two other widely available reanalysis products. Spectral analysis of ECMWF pressure series shows that the tides consist of sharp central peaks with modulating sidelines at integer multiples of 1 cycle/year, superimposed on a broad cusp of stochastic energy. The integrated energy in the cusp dominates that of the sidelines. This complicates development of a simple model that can characterize the full temporal variability of the tides.

  7. On the Temporal Variability of Low-Mode Internal Tides in the Deep Ocean

    NASA Technical Reports Server (NTRS)

    Ray, Richard D.; Zaron, E. D.

    2010-01-01

    In situ measurements of internal tides are typically characterized by high temporal variability, with strong dependence on stratification, mesoscale eddies, and background currents commonly observed. Thus, it is surprising to find phase-locked internal tides detectable by satellite altimetry. An important question is how much tidal variability is missed by altimetry. We address this question in several ways. We subset the altimetry by season and find only very small changes -- an important exception being internal tides in the South China Sea where we observe strong seasonal dependence. A wavenumber-domain analysis confirms that throughout most of the global ocean there is little temporal variability in altimetric internal-tide signals, at least in the first baroclinic mode, which is the mode that dominates surface elevation. The analysis shows higher order modes to be significantly more variable. The results of this study have important practical implications for the anticipated SWOT wide-swath altimeter mission, for which removal of internal tide signals is critical for observing non-tidal submesoscale phenomena.

  8. Intraseasonal variability and tides in Makassar Strait

    NASA Astrophysics Data System (ADS)

    Susanto, R. Dwi; Gordon, Arnold L.; Sprintall, Janet; Herunadi, Bambang

    2000-05-01

    Intraseasonal variability and tides along the Makassar Strait, the major route of Indonesian throughflow, are investigated using spectral and time-frequency analyses which are applied to sea level, wind and mooring data. Semidiurnal and diurnal tides are dominant features, with higher (lower) semidiurnal (diurnal) energy in the north compared to the south. Sea levels and mooring data display intraseasonal variability which are probably a response to remotely forced Kelvin waves from the Indian Ocean through Lombok Strait and to Rossby waves from the Pacific Ocean. Sea levels in Tarakan and Balikpapan and Makassar mooring velocities reveal intraseasonal features with periods of 48-62 days associated with Rossby waves from the Sulawesi Sea. Kelvin wave features with periods of 67-100 days are seen in Bali (Lombok Strait), at the mooring sites and in Balikpapan, however, they are not seen in Tarakan, which implies that these waves diminish after passing through the Makassar Strait.

  9. Migrating diurnal tide variability induced by propagating planetary waves

    NASA Astrophysics Data System (ADS)

    Chang, Loren C.

    the tide is smaller than the advective tendencies throughout most of the MLT region, and cannot iv directly account for the changes in the tide during the QTDW model simulation. In the case of the UFK wave, baseline tidal amplitudes are found to show much smaller changes of 10% or less, despite the larger amplitudes of the UFK wave in the lower thermosphere region compared to the QTDW. Analysis of the nonlinear advective tendencies shows smaller magnitudes than those in the the case of the QTDW, with interaction regions limited primarily to a smaller region in latitude and altitude. Increased tidal convergence in the tropical lower thermosphere is attributed to eastward forcing of the background zonal mean winds by the UFK wave. Increasing the UFK wave forcing by an order of magnitude, although unrealistic, results in changes to the tide comparable in magnitude to the case of the QTDW. While child waves generated by nonlinear advection are present with both of the propagating planetary waves examined, the QTDW produces much greater tidal variability through both nonlinear and linear advection due to its broader horizontal and vertical structure, compared to the UFK wave. Planetary wave induced background atmosphere changes can also drive tidal variability, suggesting that changes to the tidal response in the MLT can also result from this indirect coupling mechanism, in addition to nonlinear advection.

  10. The variability of SE2 tide extracted from TIMED/SABER observations

    NASA Astrophysics Data System (ADS)

    Li, X.; Wan, W.; Ren, Z.

    2017-12-01

    Based on the temperature observations of the TIMED/SABER in mesosphere/lower thermosphere region (70-110 km altitudes) and at the low latitude and midlatitude (45°S-45°N) from 2002 to 2012, the variability of the nonmigrating tide SE2 with 1 day resolution is analyzed. It is found that the climatological features (large-scale variability) of the semidiurnal nonmigrating tide with zonal wave number 2 (SE2) tide are similar with the results from the previous research works. The SE2 tide manifests mainly at the low-mid latitudes around ±30°. The northern hemisphere tidal amplitudes below 110 km are larger than the southern hemisphere tide. SE2 peaks below 110 km mainly present between 100 and 110 km altitude. The tidal amplitudes below 110 km occur a north-south asymmetry about the equator in the annual variation: in the southern hemisphere, SE2 occurs with an obvious annual variation with a maximum of tidal amplitudes in December, while in the northern one, the semiannual variations with maximum at the equinoxes. Herein, owing to the high-resolution tidal data, we could research the short-term (day-to-day) variations of SE2. We found that the day-to-day variations manifest mainly at between 100 and 110 km altitudes; it increases gradually with latitudes, and it is stronger at the low-mid latitudes; it is relatively slightly stronger around solstices than equinoxes; and it does not present a remarkably interannual variation. The SE2 day-to-day variations may be composed by the absolute amplitudes' variance and the impact of the wave phases, and the latter ones are more important.

  11. Triggering and modulation of geyser eruptions in Yellowstone National Park by earthquakes, earth tides, and weather

    USGS Publications Warehouse

    Hurwitz, Shaul; Sohn, Robert A.; Luttrell, Karen; Manga, Michael

    2014-01-01

    We analyze intervals between eruptions (IBEs) data acquired between 2001 and 2011 at Daisy and Old Faithful geysers in Yellowstone National Park. We focus our statistical analysis on the response of these geysers to stress perturbations from within the solid earth (earthquakes and earth tides) and from weather (air pressure and temperature, precipitation, and wind). We conclude that (1) the IBEs of these geysers are insensitive to periodic stresses induced by solid earth tides and barometric pressure variations; (2) Daisy (pool geyser) IBEs lengthen by evaporation and heat loss in response to large wind storms and cold air; and (3) Old Faithful (cone geyser) IBEs are not modulated by air temperature and pressure variations, wind, and precipitation, suggesting that the subsurface water column is decoupled from the atmosphere. Dynamic stress changes of 0.1−0.2 MPa resulting from the 2002 M-7.9 Denali, Alaska, earthquake surface waves caused a statistically significant shortening of Daisy geyser's IBEs. Stresses induced by other large global earthquakes during the study period were at least an order of magnitude smaller. In contrast, dynamic stresses of >0.5 MPa from three large regional earthquakes in 1959, 1975, and 1983 caused lengthening of Old Faithful's IBEs. We infer that most subannual geyser IBE variability is dominated by internal processes and interaction with other geysers. The results of this study provide quantitative bounds on the sensitivity of hydrothermal systems to external stress perturbations and have implications for studying the triggering and modulation of volcanic eruptions by external forces.

  12. Contribution of Sand-Associated Enterococci to Dry Weather Water Quality

    PubMed Central

    2015-01-01

    Culturable enterococci and a suite of environmental variables were collected during a predominantly dry summer at a beach impacted by nonpoint source pollution. These data were used to evaluate sands as a source of enterococci to nearshore waters, and to assess the relationship between environmental factors and dry-weather enterococci abundance. Best-fit multiple linear regressions used environmental variables to explain more than half of the observed variation in enterococci in water and dry sands. Notably, during dry weather the abundance of enterococci in dry sands at the mean high-tide line was significantly positively related to sand moisture content (ranging from <1–4%), and the daily mean ENT in water could be predicted by a linear regression with turbidity alone. Temperature was also positively correlated with ENT abundance in this study, which may indicate an important role of seasonal warming in temperate regions. Inundation by spring tides was the primary rewetting mechanism that sustained culturable enterococci populations in high-tide sands. Tidal forcing modulated the abundance of enterococci in the water, as both turbidity and enterococci were elevated during ebb and flood tides. The probability of samples violating the single-sample maximum was significantly greater when collected during periods with increased tidal range: spring ebb and flood tides. Tidal forcing also affected groundwater mixing zones, mobilizing enterococci from sand to water. These data show that routine monitoring programs using discrete enterococci measurements may be biased by tides and other environmental factors, providing a flawed basis for beach closure decisions. PMID:25479559

  13. Contribution of sand-associated enterococci to dry weather water quality.

    PubMed

    Halliday, Elizabeth; Ralston, David K; Gast, Rebecca J

    2015-01-06

    Culturable enterococci and a suite of environmental variables were collected during a predominantly dry summer at a beach impacted by nonpoint source pollution. These data were used to evaluate sands as a source of enterococci to nearshore waters, and to assess the relationship between environmental factors and dry-weather enterococci abundance. Best-fit multiple linear regressions used environmental variables to explain more than half of the observed variation in enterococci in water and dry sands. Notably, during dry weather the abundance of enterococci in dry sands at the mean high-tide line was significantly positively related to sand moisture content (ranging from <1-4%), and the daily mean ENT in water could be predicted by a linear regression with turbidity alone. Temperature was also positively correlated with ENT abundance in this study, which may indicate an important role of seasonal warming in temperate regions. Inundation by spring tides was the primary rewetting mechanism that sustained culturable enterococci populations in high-tide sands. Tidal forcing modulated the abundance of enterococci in the water, as both turbidity and enterococci were elevated during ebb and flood tides. The probability of samples violating the single-sample maximum was significantly greater when collected during periods with increased tidal range: spring ebb and flood tides. Tidal forcing also affected groundwater mixing zones, mobilizing enterococci from sand to water. These data show that routine monitoring programs using discrete enterococci measurements may be biased by tides and other environmental factors, providing a flawed basis for beach closure decisions.

  14. A Link between Variability of the Semidiurnal Tide and Planetary Waves in the Opposite Hemisphere

    NASA Technical Reports Server (NTRS)

    Smith, Anne K.; Pancheva, Dora V.; Mitchell, Nicholas J.; Marsh, Daniel R.; Russell, James M., III; Mlynczak, Martin G.

    2007-01-01

    Horizontal wind observations over four years from the meteor radar at Esrange (68 deg N) are analyzed to determine the variability of the semidiurnal tide. Simultaneous global observations of temperature and geopotential from the SABER satellite instrument are used to construct time series of planetary wave amplitudes and geostrophic mean zonal wind. During NH summer and fall, the temporal variability of the semidiurnal tide at Esrange is found to be well correlated with the amplitude of planetary wavenumber 1 in the stratosphere in high southern latitudes (i.e., in the opposite hemisphere). The correlations indicate that a significant part of the tidal variations at Esrange is due to dynamical interactions in the Southern Hemisphere. Other times of the year do not indicate a corresponding robust correlation pattern for the Esrange tides over multiple years.

  15. The variability of SE2 tide extracted from TIMED/SABER observations

    NASA Astrophysics Data System (ADS)

    Li, Xing; Wan, Weixing; Ren, Zhipeng; Yu, You

    2017-02-01

    Based on the temperature observations of the TIMED/Sounding of the Atmosphere using Broadband Emission Radiometry in mesosphere/lower thermosphere region (70-110 km altitudes) and at the low latitude and midlatitude (45°S-45°N) from 2002 to 2012, the variability of the nonmigrating tide SE2 with 1 day resolution is analyzed, using the method from Li et al. (2015). It is found that the climatological features (large-scale variability) of the SE2 tide are similar with the results from the previous research works. The SE2 tide manifests mainly at the low-mid latitudes around ±30°. The northern hemisphere tidal amplitudes below 110 km are larger than the southern hemisphere tide. SE2 peaks below 110 km mainly present between 100 and 110 km altitude. The tidal amplitudes below 110 km occur a north-south asymmetry about the equator in the annual variation: in the southern hemisphere, SE2 occurs with an obvious annual variation with a maximum of tidal amplitudes in December, while in the northern one, the semiannual variations with maximum at the equinoxes. Herein, owing to the high-resolution tidal data, we could research the short-term (day-to-day) variations of SE2. We found that the day-to-day variations manifest mainly at between 100 and 110 km altitudes; it increases gradually with latitudes, and it is stronger at the low-mid latitudes; it is relatively slightly stronger around solstices than equinoxes; and it does not present a remarkably interannual variation. The SE2 day-to-day variations may be composed by the absolute amplitudes' variance and the impact of the wave phases, and the latter ones are more important.

  16. Optimizing Placement of Weather Stations: Exploring Objective Functions of Meaningful Combinations of Multiple Weather Variables

    NASA Astrophysics Data System (ADS)

    Snyder, A.; Dietterich, T.; Selker, J. S.

    2017-12-01

    Many regions of the world lack ground-based weather data due to inadequate or unreliable weather station networks. For example, most countries in Sub-Saharan Africa have unreliable, sparse networks of weather stations. The absence of these data can have consequences on weather forecasting, prediction of severe weather events, agricultural planning, and climate change monitoring. The Trans-African Hydro-Meteorological Observatory (TAHMO.org) project seeks to address these problems by deploying and operating a large network of weather stations throughout Sub-Saharan Africa. To design the TAHMO network, we must determine where to place weather stations within each country. We should consider how we can create accurate spatio-temporal maps of weather data and how to balance the desired accuracy of each weather variable of interest (precipitation, temperature, relative humidity, etc.). We can express this problem as a joint optimization of multiple weather variables, given a fixed number of weather stations. We use reanalysis data as the best representation of the "true" weather patterns that occur in the region of interest. For each possible combination of sites, we interpolate the reanalysis data between selected locations and calculate the mean average error between the reanalysis ("true") data and the interpolated data. In order to formulate our multi-variate optimization problem, we explore different methods of weighting each weather variable in our objective function. These methods include systematic variation of weights to determine which weather variables have the strongest influence on the network design, as well as combinations targeted for specific purposes. For example, we can use computed evapotranspiration as a metric that combines many weather variables in a way that is meaningful for agricultural and hydrological applications. We compare the errors of the weather station networks produced by each optimization problem formulation. We also compare these

  17. Atmosphere-Ionosphere Coupling due to Atmospheric Tides (Julius Bartels Medal Lecture)

    NASA Astrophysics Data System (ADS)

    Forbes, Jeffrey M.

    2016-04-01

    Within the last decade, a new realization has arrived on the scene of ionosphere-thermosphere (IT) science: terrestrial weather significantly influences space weather. The aspect of space weather referred to here consists of electron density variability that translates to uncertainties in navigation and communications systems, and neutral density variability that translates to uncertainties in orbital and reentry predictions. In the present context "terrestrial weather" primarily refers to the meteorological conditions that determine the spatial-temporal distribution of tropospheric water vapor and latent heating associated with tropical convection, and the middle atmosphere disturbances associated with sudden stratosphere warmings. The net effect of these processes is a spatially- and temporally-evolving spectrum of waves (gravity waves, tides, planetary waves, Kelvin waves) that grows in amplitude with height and enters the IT system near ~100 km. Some members of the wave spectrum penetrate all the way to the base of the exosphere (ca. 500 km). Along the way, nonlinear interactions between different wave components occur, modifying the interacting waves and giving rise to secondary waves. Finally, the IT wind perturbations carried by the waves can redistribute ionospheric plasma, either through the electric fields generated via the dynamo mechanism between 100 and 150 km, or directly by moving plasma along magnetic field lines at higher levels. Additionally, the signatures of wave-driven dynamo currents are reflected in magnetic perturbations observed at the ground. This is how terrestrial atmospheric variability, through the spectrum of vertically- propagating waves that it produces, can effectively drive IT space weather. The primary objective of this Julius Bartels Lecture is to provide an overview of the global observational evidence for the IT consequences of these upward-propagating waves. In honor of Julius Bartels, who performed much research (including

  18. New Jersey Tide Telemetry System

    USGS Publications Warehouse

    Hoppe, Heidi L.

    2007-01-01

    Each summer the population of the barrier-island communities of New Jersey increases by tens of thousands. When a coastal storm threatens these communities, the limited number of bridges and causeways that connect the islands with the mainland become overcrowded, making evacuations from the barrier islands to the mainland difficult. Timely evacuation depends on well-defined emergency evacuation plans used in conjunction with accurate flood forecasting and up to the minute (real-time) tide-level information. The 'Great Nor'easter' storm that struck the coastal areas of New Jersey on December 11, 1992, caused about $270 million in insured damages to public and private property (Dorr and others, 1995). Most of the damage was due to tidal flooding and storm surge, which were especially severe along the back bay areas. Comprehensive and reliable tide-level and meteorological data for the back bays was needed to make accurate flood forecasts. Collection of tidal data for the ocean and large bays was adequately covered by the National Oceanic and Atmospheric Administration's National Ocean Service (NOAA's NOS), but in New Jersey little to no data are available for the back-bay areas. The back bays behave quite differently than the ocean as a result of the complex interaction between the winds and the geometry of the inlets and bays. A slow moving Nor'easter can keep tide levels in back bays several feet higher than the ocean tide by not allowing tides to recede, resulting in flooding of bridges and causeways that link the barrier islands to the mainland. The U.S. Geological Survey (USGS), in cooperation with the New Jersey Department of Transportation (NJDOT), designed and installed the New Jersey Tide Telemetry System (NJTTS) with assistance from NOAA's NOS in 1997. This system is part of a statewide network of tide gages, weather stations, and stream gages that collect data in real time. The NJTTS supplies comprehensive, reliable real-time tide-level and meteorological

  19. The variability of SE2 tide extracted from TIMED/SABER observations

    NASA Astrophysics Data System (ADS)

    Li, Xing; Wan, Weixing; Ren, Zhipeng; Yu, You

    2017-04-01

    Based on the temperature observations of the SABER/TIMED, the variability of the non-migrating tide SE2 with high resolution (one-day) is analyzed, using the method from Li et al., [2015]. From the temperature observation data measured in the mesosphere and lower atmosphere region (MLT, 70-110 km altitudes) and at the low- and mid -latitudes (45S - 45N) from2002 to 2012), we obtained the non-migrating tide SE2 and further studied it in detail. It is found that the climatological features (large time scale variability and spatial distribution) of the SE2 tidal component are similar with the results from the previous researches, which are picked up from the interpolated data with 60-day resolution. The climatological features are that the SE2 tidal component manifests mainly at the low-mid latitudes around 30. The northern hemisphere tidal amplitudes below 110 km are larger than the southern hemisphere tide, at the same time, its peaks below 110 km mainly present between 100 and 110 km altitude; the tidal amplitudes below 110 km occur a north-south asymmetry about the equator in the annual variation: in the southern hemisphere, SE2 occurs with an obvious annual variation with a maximum of tidal amplitudes in December; while, in the northern one, the semi-annual variations with maximum at the equinoxes are stronger than that in the southern one. Herein, owing to the high-resolution tidal data (one day), we could research the short term (day-to-day) variations of the SE2 tide. We found that: (1) the day-to-day variations manifests mainly at the altitudes range between 100 and 110 km; (2) it increases gradually with latitudes and it is stronger at the low-mid latitudes; (3) it is relatively slightly stronger around solstices than equinoxes; (4) it does not present a remarkably inter-annual variation. Finally, the SE2 day-to-day variations may be composed by the absolute amplitudes' variance and the impact of the wave phases. In addition, the variations of

  20. Temperature variability caused by internal tides in the coral reef ecosystem of Hanauma bay, Hawai'i

    NASA Astrophysics Data System (ADS)

    Smith, Katharine A.; Rocheleau, Greg; Merrifield, Mark A.; Jaramillo, Sergio; Pawlak, Geno

    2016-03-01

    Hanauma Bay Nature Preserve is a shallow bay (<30 m depth) on the island of O'ahu, Hawai'i, offshore of which tidal flow over deep ridge topography (500-1000 m depth) is known to generate semidiurnal frequency internal tides. A field experiment was conducted during March to June 2009 to determine whether the deep internal tides propagate shoreward to influence variability in temperature and currents in the bay environment. Temperature observations in the bay exhibit a diurnal cycle that is strongest near the surface (upper 10 m) and is associated with solar heating. In early summer (May-June), as the upper mixed layer warms and a shallow seasonal thermocline develops, temperature fluctuations in deeper bay waters (>15 m depth) become dominated by large semidiurnal variations (up to 2.7 °C) that are attributed to the internal tide. These temperature drops caused by the internal tide occur consistently twice a day under summer stratification at depths as shallow as 15 m, while smaller temperature drops (up to 1.8 °C) occur occasionally at 5 m. Although semidiurnal band temperatures vary seasonally, semidiurnal band currents exhibit similar magnitudes in spring and summer. This suggests that the weak temperature fluctuations in spring are due to the bay residing entirely in the upper mixed layer at this time of year, while internal tide energy continues to influence currents. Observations made along a cross-shore/vertical transect at the center of the bay with an autonomous underwater vehicle highlight the structure of cold intrusions that fill a large portion of the bay as well as the relationship between temperature, salinity, chlorophyll, and backscatter. Near-bottom, advective heat flux estimates at the mouth of the bay indicate that the internal tide tends to advect cold water into the bay primarily on the northeast side of the bay entrance, with cold water outflow on the opposite side. The observations highlight the role of the internal tide along with

  1. Long term variabilities and tendencies of mesospheric lunar semidiurnal tide over Tirunelveli (8.7°N, 77.8°E)

    NASA Astrophysics Data System (ADS)

    Sathishkumar, S.; Sridharan, S.; Muhammed Kutty, P. V.; Gurubaran, S.

    2017-10-01

    The medium frequency radar deployed at Tirunelveli (8.7°N, 77.8°E), which is located near the southmost tip of peninsular India, have been providing continuous data from the year 1993 to the year 2012 that helped to study the long term tendencies in the lunar tidal variabilities over this geographic location. In the present paper we present the results of seasonal, interannual and long-term variabilities of lunar semi-diurnal tides in the upper mesosphere over Tirunelveli. The present study also includes comparison with model values. The study shows that the tidal amplitudes are larger in the meridional components of the mesospheric winds than the zonal winds. The seasonal variations of the tides are similar in both the components. The tides show maximum amplitudes of about ∼5 m/s in February/March, secondary maximum amplitudes of about ∼3 m/s in September and minimum amplitudes during summer months (May-August). The observed seasonal variation of the lunar tides do not compare well with Vial and Forbes (1994) model values, though it is consistent with earlier observations. The lunar tidal phase in meridional winds leads that in zonal winds from January to June and from September to November, while the latter leads the former during July/August. The lunar tides show large interannual variability. There are unusual amplitude enhancements in the lunar tide in meridional winds during the winters of 2006 and 2009, when major sudden stratospheric warmings (SSW) occurred at high latitude northern hemisphere, whereas zonal lunar tide does not show any clear association with the SSW. Vertical wavelengths of lunar tides in zonal and meridional wind are in the range of 20-90 km. The vertical wavelengths of lunar tides in both zonal and meridional component are smaller in June and larger in November and December. The monthly mean zonal and meridional winds are subjected to regression analysis to study the tidal response to long-period oscillations, namely, quasi

  2. Ionosphere variability during the 2009 SSW: Influence of the lunar semidiurnal tide and mechanisms producing electron density variability

    NASA Astrophysics Data System (ADS)

    Pedatella, N. M.; Liu, H.-L.; Sassi, F.; Lei, J.; Chau, J. L.; Zhang, X.

    2014-05-01

    To investigate ionosphere variability during the 2009 sudden stratosphere warming (SSW), we present simulation results that combine the Whole Atmosphere Community Climate Model Extended version and the thermosphere-ionosphere-mesosphere electrodynamics general circulation model (TIME-GCM). The simulations reveal notable enhancements in both the migrating semidiurnal solar (SW2) and lunar (M2) tides during the SSW. The SW2 and M2 amplitudes reach ˜50 m s-1 and ˜40 m s-1, respectively, in zonal wind at E region altitudes. The dramatic increase in the M2 at these altitudes influences the dynamo generation of electric fields, and the importance of the M2 on the ionosphere variability during the 2009 SSW is demonstrated by comparing simulations with and without the M2. TIME-GCM simulations that incorporate the M2 are found to be in good agreement with Jicamarca Incoherent Scatter Radar vertical plasma drifts and Constellation Observing System for Meteorology, Ionosphere, and Climate (COSMIC) observations of the maximum F region electron density. The agreement with observations is worse if the M2 is not included in the simulation, demonstrating that the lunar tide is an important contributor to the ionosphere variability during the 2009 SSW. We additionally investigate sources of the F region electron density variability during the SSW. The primary driver of the electron density variability is changes in electric fields. Changes in meridional neutral winds and thermosphere composition are found to also contribute to the electron density variability during the 2009 SSW. The electron density variability for the 2009 SSW is therefore not solely due to variability in electric fields as previously thought.

  3. Winter variability in the western Gulf of Maine: Part 1: Internal tides

    NASA Astrophysics Data System (ADS)

    Brown, W. S.

    2011-09-01

    During the winter 1997-1998, a field program was conducted in Wilkinson Basin-western Gulf of Maine-as part of a study of winter convective mixing. The field program consisted of (1) Wilkinson basin-scale hydrographic surveys, (2) a tight three-mooring array with ˜100 m separations measured temperature and conductivity at rates of 2-15 min and (3) a single pair of upward/downward-looking pair acoustic Doppler current profiling (ADCP) instruments measured currents with 8 m vertical resolution over the 270 m water column in north-central Wilkinson basin at a rate of 10 min. The moored array measurements below the mixed layer (˜100 m depth) between 11 January and 6 February 1998 were dominated by a combination of the relatively strong semidiurnal external (depth-independent or barotropic) tide; upon which were superposed a weaker phase-locked semidiurnal internal tide and a very weak water column mean currents of about 1 cm/s southward or approximately across the local isobaths. The harmonic analysis of a vertical average of the relatively uniform ADCP velocities in the well-mixed upper 123 m of the water column, defined the external tidal currents which were dominated by a nearly rectilinear, across-isobath (326°T) M 2 semidiurnal tidal current of about 15 cm/s. The depth-dependent residual current field, which was created by subtracting the external tidal current, consisted of (1) clockwise-rotating semidiurnal internal tidal currents of about 5 cm/s below the mixed layer; (2) clockwise-rotating inertial currents; and (3) a considerably less energetic subtidal current variability. The results from both frequency-domain empirical orthogonal function and tidal harmonic analyses of the of isotherm displacement series at each of the three moorings in the 100 m array mutually confirm an approximate east-northeastward phase propagation of the dominant M 2 semidiurnal internal tide across Wilkinson Basin. Further investigation supports the idea that this winter internal

  4. Climatic, high tide and vector variables and the transmission of Ross River virus.

    PubMed

    Tong, S; Hu, W; Nicholls, N; Dale, P; MacKenzie, J S; Patz, J; McMichael, A J

    2005-11-01

    This report assesses the impact of the variability in environmental and vector factors on the transmission of Ross River virus (RRV) in Brisbane, Australia. Poisson time series regression analyses were conducted using monthly data on the counts of RRV cases, climate variables (Southern Oscillation Index and rainfall), high tides and mosquito density for the period of 1998-2001. The results indicate that increases in the high tide (relative risk (RR): 1.65; 95% confidence interval (CI): 1.20-2.26), rainfall (RR: 1.45; 95% CI: 1.21-1.73), mosquito density (RR: 1.17; 95% CI: 1.09-1.27), the density of Culex annulirostris (RR: 1.25; 95% CI: 1.13-1.37) and the density of Ochlerotatus vigilax (RR: 2.39; 95% CI: 2.30-2.48), each at a lag of 1 month, were statistically significantly associated with the rise of monthly RRV incidence. The results of the present study might facilitate the development of early warning systems for reducing the incidence of this wide-spread disease in Australia and other Pacific island nations.

  5. Using an Altimeter-Derived Internal Tide Model to Remove Tides from in Situ Data

    NASA Technical Reports Server (NTRS)

    Zaron, Edward D.; Ray, Richard D.

    2017-01-01

    Internal waves at tidal frequencies, i.e., the internal tides, are a prominent source of variability in the ocean associated with significant vertical isopycnal displacements and currents. Because the isopycnal displacements are caused by ageostrophic dynamics, they contribute uncertainty to geostrophic transport inferred from vertical profiles in the ocean. Here it is demonstrated that a newly developed model of the main semidiurnal (M2) internal tide derived from satellite altimetry may be used to partially remove the tide from vertical profile data, as measured by the reduction of steric height variance inferred from the profiles. It is further demonstrated that the internal tide model can account for a component of the near-surface velocity as measured by drogued drifters. These comparisons represent a validation of the internal tide model using independent data and highlight its potential use in removing internal tide signals from in situ observations.

  6. Variable allelopathy among phytoplankton reflected in red tide metabolome.

    PubMed

    Poulin, Remington X; Poulson-Ellestad, Kelsey L; Roy, Jessie S; Kubanek, Julia

    2018-01-01

    Harmful algae are known to utilize allelopathy, the release of compounds that inhibit competitors, as a form of interference competition. Competitor responses to allelopathy are species-specific and allelopathic potency of producing algae is variable. In the current study, the biological variability in allelopathic potency was mapped to the underlying chemical variation in the exuded metabolomes of five genetic strains of the red tide dinoflagellate Karenia brevis using 1 H nuclear magnetic resonance (NMR) spectroscopy. The impacts of K. brevis allelopathy on growth of a model competitor, Asterionellopsis glacialis, ranged from strongly inhibitory to negligible to strongly stimulatory. Unique metabolomes of K. brevis were visualized as chemical fingerprints, suggesting three distinct metabolic modalities - allelopathic, non-allelopathic, and stimulatory - with each modality distinguished from the others by different concentrations of several metabolites. Allelopathic K. brevis was characterized by enhanced concentrations of fatty acid-derived lipids and aromatic or other polyunsaturated compounds, relative to less allelopathic K. brevis. These findings point to a previously untapped source of information in the study of allelopathy: the chemical variability of phytoplankton, which has been underutilized in the study of bloom dynamics and plankton chemical ecology. Copyright © 2017 Elsevier B.V. All rights reserved.

  7. Solar variability, weather, and climate

    NASA Technical Reports Server (NTRS)

    1982-01-01

    Advances in the understanding of possible effects of solar variations on weather and climate are most likely to emerge by addressing the subject in terms of fundamental physical principles of atmospheric sciences and solar-terrestrial physis. The limits of variability of solar inputs to the atmosphere and the depth in the atmosphere to which these variations have significant effects are determined.

  8. Dynamic and Regression Modeling of Ocean Variability in the Tide-Gauge Record at Seasonal and Longer Periods

    NASA Technical Reports Server (NTRS)

    Hill, Emma M.; Ponte, Rui M.; Davis, James L.

    2007-01-01

    Comparison of monthly mean tide-gauge time series to corresponding model time series based on a static inverted barometer (IB) for pressure-driven fluctuations and a ocean general circulation model (OM) reveals that the combined model successfully reproduces seasonal and interannual changes in relative sea level at many stations. Removal of the OM and IB from the tide-gauge record produces residual time series with a mean global variance reduction of 53%. The OM is mis-scaled for certain regions, and 68% of the residual time series contain a significant seasonal variability after removal of the OM and IB from the tide-gauge data. Including OM admittance parameters and seasonal coefficients in a regression model for each station, with IB also removed, produces residual time series with mean global variance reduction of 71%. Examination of the regional improvement in variance caused by scaling the OM, including seasonal terms, or both, indicates weakness in the model at predicting sea-level variation for constricted ocean regions. The model is particularly effective at reproducing sea-level variation for stations in North America, Europe, and Japan. The RMS residual for many stations in these areas is 25-35 mm. The production of "cleaner" tide-gauge time series, with oceanographic variability removed, is important for future analysis of nonsecular and regionally differing sea-level variations. Understanding the ocean model's strengths and weaknesses will allow for future improvements of the model.

  9. Seasonal variability of Internal tide energetics in the western Bay of Bengal

    NASA Astrophysics Data System (ADS)

    Mohanty, S.; Rao, A. D.

    2017-12-01

    The Internal Waves (IWs) are generated by the flow of barotropic tide over the rapidly varying and steep topographic features like continental shelf slope, seamounts, etc. These waves are an important phenomena in the ocean due to their influence on the density structure and energy transfer into the region. Such waves are also important in submarine acoustics, underwater navigation, offshore structures, ocean mixing and biogeochemical processes, etc. over the shelf-slope region. The seasonal variability of internal tides in the western Bay of Bengal is examined by using three-dimensional MITgcm model. The numerical simulations are performed for different periods covering August-September, 2013; November-December, 2013 and March-April, 2014 representing monsoon, post-monsoon and pre-monsoon seasons respectively during which high temporal resolution observed data sets are available. The model is initially validated through the spectral estimate of density and the baroclinic velocities. From the estimate, it is found that its peak is associated with the semi-diurnal frequency at all the depths in both observations and model simulations for November-December and March-April. However in August, the estimate is found to be maximum near the inertial frequency at all available depths. EOF analysis suggests that about 70-80% of the total variance comes from Mode-1 semi-diurnal internal tide in both observations as well as in the model simulations. The phase speed, group speed and wavelength are found to be maximum for post-monsoon season compared to other two seasons. To understand the generation and propagation of internal tides over this region, barotropic-to-baroclinic M2 tidal energy conversion and energy flux are examined. The barotropic-to-baroclinic conversion occurs intensively along the shelf-slope regions and propagate towards the coast. The model simulated energy dissipation rate infers that its maximum occurs at the generation sites and hence the local mixing

  10. Understanding the weather signal in national crop-yield variability

    NASA Astrophysics Data System (ADS)

    Frieler, Katja; Schauberger, Bernhard; Arneth, Almut; Balkovič, Juraj; Chryssanthacopoulos, James; Deryng, Delphine; Elliott, Joshua; Folberth, Christian; Khabarov, Nikolay; Müller, Christoph; Olin, Stefan; Pugh, Thomas A. M.; Schaphoff, Sibyll; Schewe, Jacob; Schmid, Erwin; Warszawski, Lila; Levermann, Anders

    2017-06-01

    Year-to-year variations in crop yields can have major impacts on the livelihoods of subsistence farmers and may trigger significant global price fluctuations, with severe consequences for people in developing countries. Fluctuations can be induced by weather conditions, management decisions, weeds, diseases, and pests. Although an explicit quantification and deeper understanding of weather-induced crop-yield variability is essential for adaptation strategies, so far it has only been addressed by empirical models. Here, we provide conservative estimates of the fraction of reported national yield variabilities that can be attributed to weather by state-of-the-art, process-based crop model simulations. We find that observed weather variations can explain more than 50% of the variability in wheat yields in Australia, Canada, Spain, Hungary, and Romania. For maize, weather sensitivities exceed 50% in seven countries, including the United States. The explained variance exceeds 50% for rice in Japan and South Korea and for soy in Argentina. Avoiding water stress by simulating yields assuming full irrigation shows that water limitation is a major driver of the observed variations in most of these countries. Identifying the mechanisms leading to crop-yield fluctuations is not only fundamental for dampening fluctuations, but is also important in the context of the debate on the attribution of loss and damage to climate change. Since process-based crop models not only account for weather influences on crop yields, but also provide options to represent human-management measures, they could become essential tools for differentiating these drivers, and for exploring options to reduce future yield fluctuations.

  11. Mapping the nonstationary internal tide with satellite altimetry

    NASA Astrophysics Data System (ADS)

    Zaron, Edward D.

    2017-01-01

    Temporal variability of the internal tide has been inferred from the 23 year long combined records of the TOPEX/Poseidon, Jason-1, and Jason-2 satellite altimeters by combining harmonic analysis with an analysis of along-track wavenumber spectra of sea-surface height (SSH). Conventional harmonic analysis is first applied to estimate and remove the stationary components of the tide at each point along the reference ground tracks. The wavenumber spectrum of the residual SSH is then computed, and the variance in a neighborhood around the wavenumber of the mode-1 baroclinic M2 tide is interpreted as the sum of noise, broadband nontidal processes, and the nonstationary tide. At many sites a bump in the spectrum associated with the internal tide is noted, and an empirical model for the noise and nontidal processes is used to estimate the nonstationary semidiurnal tidal variance. The results indicate a spatially inhomogeneous pattern of tidal variability. Nonstationary tides are larger than stationary tides throughout much of the equatorial Pacific and Indian Oceans.

  12. Ocean tides for satellite geodesy

    NASA Technical Reports Server (NTRS)

    Dickman, S. R.

    1990-01-01

    Spherical harmonic tidal solutions have been obtained at the frequencies of the 32 largest luni-solar tides using prior theory of the author. That theory was developed for turbulent, nonglobal, self-gravitating, and loading oceans possessing realistic bathymetry and linearized bottom friction; the oceans satisfy no-flow boundary conditions at coastlines. In this theory the eddy viscosity and bottom drag coefficients are treated as spatially uniform. Comparison of the predicted degree-2 components of the Mf, P1, and M2 tides with those from numerical and satellite-based tide models allows the ocean friction parameters to be estimated at long and short periods. Using the 32 tide solutions, the frequency dependence of tidal admittance is investigated, and the validity of sideband tide models used in satellite orbit analysis is examined. The implications of admittance variability for oceanic resonances are also explored.

  13. Identification of weather variables sensitive to dysentery in disease-affected county of China.

    PubMed

    Liu, Jianing; Wu, Xiaoxu; Li, Chenlu; Xu, Bing; Hu, Luojia; Chen, Jin; Dai, Shuang

    2017-01-01

    Climate change mainly refers to long-term change in weather variables, and it has significant impact on sustainability and spread of infectious diseases. Among three leading infectious diseases in China, dysentery is exclusively sensitive to climate change. Previous researches on weather variables and dysentery mainly focus on determining correlation between dysentery incidence and weather variables. However, the contribution of each variable to dysentery incidence has been rarely clarified. Therefore, we chose a typical county in epidemic of dysentery as the study area. Based on data of dysentery incidence, weather variables (monthly mean temperature, precipitation, wind speed, relative humidity, absolute humidity, maximum temperature, and minimum temperature) and lagged analysis, we used principal component analysis (PCA) and classification and regression trees (CART) to examine the relationships between the incidence of dysentery and weather variables. Principal component analysis showed that temperature, precipitation, and humidity played a key role in determining transmission of dysentery. We further selected weather variables including minimum temperature, precipitation, and relative humidity based on results of PCA, and used CART to clarify contributions of these three weather variables to dysentery incidence. We found when minimum temperature was at a high level, the high incidence of dysentery occurred if relative humidity or precipitation was at a high level. We compared our results with other studies on dysentery incidence and meteorological factors in areas both in China and abroad, and good agreement has been achieved. Yet, some differences remain for three reasons: not identifying all key weather variables, climate condition difference caused by local factors, and human factors that also affect dysentery incidence. This study hopes to shed light on potential early warnings for dysentery transmission as climate change occurs, and provide a theoretical

  14. National Weather Service Forecast Office - Honolulu, Hawai`i

    Science.gov Websites

    Locations - Coastal Forecast Kauai Northwest Waters Kauai Windward Waters Kauai Leeward Waters Kauai Channel Coastal Wind Observations Buoy Reports, and current weather conditions for selected locations tides , sunrise and sunset information Coastal Waters Forecast general weather overview Tropical information

  15. National Weather Service Forecast Office - Honolulu, Hawai`i

    Science.gov Websites

    Locations - Coastal Forecast Kauai Northwest Waters Kauai Windward Waters Kauai Leeward Waters Kauai Channel Oahu Forecast Oahu Surf Forecast Coastal Wind Observations Buoy Reports, and current weather conditions for selected locations tides, sunrise and sunset information Coastal Waters Forecast general weather

  16. Seasonal variability of atmospheric tides in the mesosphere and lower thermosphere: meteor radar data and simulations

    NASA Astrophysics Data System (ADS)

    Pokhotelov, Dimitry; Becker, Erich; Stober, Gunter; Chau, Jorge L.

    2018-06-01

    Thermal tides play an important role in the global atmospheric dynamics and provide a key mechanism for the forcing of thermosphere-ionosphere dynamics from below. A method for extracting tidal contributions, based on the adaptive filtering, is applied to analyse multi-year observations of mesospheric winds from ground-based meteor radars located in northern Germany and Norway. The observed seasonal variability of tides is compared to simulations with the Kühlungsborn Mechanistic Circulation Model (KMCM). It is demonstrated that the model provides reasonable representation of the tidal amplitudes, though substantial differences from observations are also noticed. The limitations of applying a conventionally coarse-resolution model in combination with parametrisation of gravity waves are discussed. The work is aimed towards the development of an ionospheric model driven by the dynamics of the KMCM.

  17. LINKS to NATIONAL WEATHER SERVICE MARINE FORECAST OFFICES

    Science.gov Websites

    Coastal Flooding Tsunamis 406 EPIRB's National Weather Service Marine Forecasts LINKS to NATIONAL WEATHER Marine Forecasts in text form ) Coastal NWS Forecast Offices have regionally focused marine webpages which are overflowing with information such as coastal forecasts, predicted tides, and buoy observations

  18. Short-term variability in the ionosphere due to the nonlinear interaction between the 6 day wave and migrating tides

    NASA Astrophysics Data System (ADS)

    Gan, Quan; Oberheide, Jens; Yue, Jia; Wang, Wenbin

    2017-08-01

    Using the thermosphere-ionosphere-mesosphere electrodynamics general circulation model simulations, we investigate the short-term ionospheric variability due to the child waves and altered tides produced by the nonlinear interaction between the 6 day wave and migrating tides. Via the Fourier spectral diagnostics and least squares fittings, the [21 h, W2] and [13 h, W1] child waves, generated by the interaction of the 6 day wave with the DW1 and SW2, respectively, are found to play the leading roles on the subdiurnal variability (e.g., ±10 m/s in the ion drift and 50% in the NmF2) in the F region vertical ion drift changes through the dynamo modulation induced by the low-latitude zonal wind and the meridional wind at higher latitudes. The relatively minor contribution of the [11 h, W3] child wave is explicit as well. Although the [29 h, W0] child wave has the largest magnitude in the E region, its effect is totally absent in the vertical ion drift due to the zonally uniform structure. But the [29 h, W0] child wave shows up in the NmF2. It is found that the NmF2 short-term variability is attributed to the wave modulations on both E region dynamo and in situ F region composition. Also, the altered migrating tides due to the interaction will not contribute to the ionospheric changes significantly.

  19. Weather variability and adaptive management for rangeland restoration

    USDA-ARS?s Scientific Manuscript database

    Inherent weather variability in upland rangeland systems requires relatively long-term goal setting, and contingency planning for partial success or failure in any given year. Rangeland plant communities are dynamic systems and successional planning is essential for achieving and maintaining system...

  20. Impact of non-migrating tides on the low latitude ionosphere during a sudden stratospheric warming event in January 2010

    NASA Astrophysics Data System (ADS)

    McDonald, S. E.; Sassi, F.; Tate, J.; McCormack, J.; Kuhl, D. D.; Drob, D. P.; Metzler, C.; Mannucci, A. J.

    2018-06-01

    The lower atmosphere contributes significantly to the day-to-day variability of the ionosphere, especially during solar minimum conditions. Ionosphere/atmosphere model simulations that incorporate meteorology from data assimilation analysis products can be critically important for elucidating the physical processes that have substantial impact on ionospheric weather. In this study, the NCAR Whole Atmosphere Community Climate Model, extended version with specified dynamics (SD-WACCM-X) is coupled with an ionospheric model (Sami3 is Another Model of the Ionosphere) to study day-to-day variability in the ionosphere during January 2010. Lower atmospheric weather patterns are introduced into the SAMI3/SD-WACCM-X simulations using the 6-h Navy Operational Global Atmospheric Prediction System-Advanced Level Physics High Altitude (NOGAPS-ALPHA) data assimilation products. The same time period is simulated using the new atmospheric forecast model, the High Altitude Navy Global Environmental Model (HA-NAVGEM), a hybrid 4D-Var prototype data assimilation with the ability to produce meteorological fields at a 3-h cadence. Our study shows that forcing SD-WACCM-X with HA-NAVGEM better resolves the semidiurnal tides and introduces more day-to-day variability into the ionosphere than forcing with NOGAPS-ALPHA. The SAMI3/SD-WACCM-X/HA-NAVGEM simulation also more accurately captures the longitudinal variability associated with non-migrating tides in the equatorial ionization anomaly (EIA) region as compared to total electron content (TEC) maps derived from GPS data. Both the TEC maps and the SAMI3/SD-WACCM-X/HA-NAVGEM simulation show an enhancement in TEC over South America during 17-21 January 2010, which coincides with the commencement of a stratospheric warming event on 19 January 2010. Analysis of the SAMI3/SD-WACCM-X/HA-NAVGEM simulations indicates non-migrating tides (including DW4, DE2 and SW5) played a role during 17-21 January in shifting the phase of the wave-3 pattern in

  1. On the variability of Pacific Ocean tides at seasonal to decadal time scales: Observed vs modelled

    NASA Astrophysics Data System (ADS)

    Devlin, Adam Thomas

    forward in time to the predicted sea level in 2100. Results suggest that stations with large positive combined A-TATs produce total water levels that are greater than those predicted by an increase in MSL alone, increasing the chances of high-water events. Part II examines the mechanisms behind the yearly (TAT) variability in the Western Tropical Pacific Ocean. Significant amplitude TATs are found at more than half of 26 gauges for each of the two strongest tidal constituents, K1 (diurnal) and M2 (semidiurnal). For the lesser constituents analyzed (O1 and S2), significant trends are observed at ten gauges. Part III analyzes the seasonal behavior of tides (STATs) at twenty tide gauges in the Southeast Asian waters, which exhibit variation by 10 -- 30% of mean tidal amplitudes. A barotropic ocean tide model that considers the seasonal effects of MSL, stratification, and geostrophic and Ekman velocity is used to explain the observed seasonal variability in tides due to variations in monsoon-influenced climate forcing, with successful results at about half of all gauges. The observed changes in tides are best explained by the influence of non-tidal velocities (geostrophic and Ekman), though the effect of changing stratification is also an important secondary causative mechanism. From the results of these surveys and investigations, it is concluded that short-term fluctuations in MSL and tidal properties at multiple time scales may be as important in determining the state of future water levels as the long-term trends. Global explanations for the observed tidal behavior have not been found in this study; however, significant regional explanations are found at the yearly time scale in the Solomon Sea, and at the seasonal time scale in Southeast Asia. It is likely that tidal sensitivity to annual and seasonal variations in MSL at other locations also are driven by locally specific processes, rather than factors with basin-wide coherence. (Abstract shortened by ProQuest.).

  2. Ocean Tide Influences on the Antarctic and Greenland Ice Sheets

    NASA Astrophysics Data System (ADS)

    Padman, Laurie; Siegfried, Matthew R.; Fricker, Helen A.

    2018-03-01

    Ocean tides are the main source of high-frequency variability in the vertical and horizontal motion of ice sheets near their marine margins. Floating ice shelves, which occupy about three quarters of the perimeter of Antarctica and the termini of four outlet glaciers in northern Greenland, rise and fall in synchrony with the ocean tide. Lateral motion of floating and grounded portions of ice sheets near their marine margins can also include a tidal component. These tide-induced signals provide insight into the processes by which the oceans can affect ice sheet mass balance and dynamics. In this review, we summarize in situ and satellite-based measurements of the tidal response of ice shelves and grounded ice, and spatial variability of ocean tide heights and currents around the ice sheets. We review sensitivity of tide heights and currents as ocean geometry responds to variations in sea level, ice shelf thickness, and ice sheet mass and extent. We then describe coupled ice-ocean models and analytical glacier models that quantify the effect of ocean tides on lower-frequency ice sheet mass loss and motion. We suggest new observations and model developments to improve the representation of tides in coupled models that are used to predict future ice sheet mass loss and the associated contribution to sea level change. The most critical need is for new data to improve maps of bathymetry, ice shelf draft, spatial variability of the drag coefficient at the ice-ocean interface, and higher-resolution models with improved representation of tidal energy sinks.

  3. Ocean tides

    NASA Technical Reports Server (NTRS)

    Hendershott, M. C.

    1975-01-01

    A review of recent developments in the study of ocean tides and related phenomena is presented. Topics briefly discussed include: the mechanism by which tidal dissipation occurs; continental shelf, marginal sea, and baroclinic tides; estimation of the amount of energy stored in the tide; the distribution of energy over the ocean; the resonant frequencies and Q factors of oceanic normal modes; the relationship of earth tides and ocean tides; and numerical global tidal models.

  4. Impact of tidal density variability on orbital and reentry predictions

    NASA Astrophysics Data System (ADS)

    Leonard, J. M.; Forbes, J. M.; Born, G. H.

    2012-12-01

    Since the first satellites entered Earth orbit in the late 1950's and early 1960's, the influences of solar and geomagnetic variability on the satellite drag environment have been studied, and parameterized in empirical density models with increasing sophistication. However, only within the past 5 years has the realization emerged that "troposphere weather" contributes significantly to the "space weather" of the thermosphere, especially during solar minimum conditions. Much of the attendant variability is attributable to upward-propagating solar tides excited by latent heating due to deep tropical convection, and solar radiation absorption primarily by water vapor and ozone in the stratosphere and mesosphere, respectively. We know that this tidal spectrum significantly modifies the orbital (>200 km) and reentry (60-150 km) drag environments, and that these tidal components induce longitude variability not yet emulated in empirical density models. Yet, current requirements for improvements in orbital prediction make clear that further refinements to density models are needed. In this paper, the operational consequences of longitude-dependent tides are quantitatively assessed through a series of orbital and reentry predictions. We find that in-track prediction differences incurred by tidal effects are typically of order 200 ± 100 m for satellites in 400-km circular orbits and 15 ± 10 km for satellites in 200-km circular orbits for a 24-hour prediction. For an initial 200-km circular orbit, surface impact differences of order 15° ± 15° latitude are incurred. For operational problems with similar accuracy needs, a density model that includes a climatological representation of longitude-dependent tides should significantly reduce errors due to this source.

  5. What weather variables are important in predicting heat-related mortality? A new application of statistical learning methods

    PubMed Central

    Zhang, Kai; Li, Yun; Schwartz, Joel D.; O'Neill, Marie S.

    2014-01-01

    Hot weather increases risk of mortality. Previous studies used different sets of weather variables to characterize heat stress, resulting in variation in heat-mortality- associations depending on the metric used. We employed a statistical learning method – random forests – to examine which of various weather variables had the greatest impact on heat-related mortality. We compiled a summertime daily weather and mortality counts dataset from four U.S. cities (Chicago, IL; Detroit, MI; Philadelphia, PA; and Phoenix, AZ) from 1998 to 2006. A variety of weather variables were ranked in predicting deviation from typical daily all-cause and cause-specific death counts. Ranks of weather variables varied with city and health outcome. Apparent temperature appeared to be the most important predictor of heat-related mortality for all-cause mortality. Absolute humidity was, on average, most frequently selected one of the top variables for all-cause mortality and seven cause-specific mortality categories. Our analysis affirms that apparent temperature is a reasonable variable for activating heat alerts and warnings, which are commonly based on predictions of total mortality in next few days. Additionally, absolute humidity should be included in future heat-health studies. Finally, random forests can be used to guide choice of weather variables in heat epidemiology studies. PMID:24834832

  6. Low frequency North Atlantic SST variability: Weather noise forcing and coupled response

    NASA Astrophysics Data System (ADS)

    Fan, Meizhu

    A method to diagnose the causes of low frequency SST variability is developed, tested and applied in an ideal case and real climate. In the ideal case, a free simulation of the COLA CGCM is taken as synthetic observations. For real climate, we take NCEP reanalysis atmospheric data and Reynolds SST as observations. Both the synthetic and actual observation data show that weather noise is the main component of atmospheric variability at subtropics and high-latitude. Diagnoses of results from the ideal case suggest that most of the synthetic observed SST variability can be reproduced by the weather noise surface fluxes forcing. This includes the "observed" low frequency SST patterns in the North Atlantic and their corresponding time evolution. Among all the noise surface fluxes, heat flux plays a major role. The results from simulations using actual observations also suggest that the observed SST variability is mostly atmospheric weather noise forced. The regional atmospheric noise forcing, especially the heat flux noise forcing, is the major source of the low frequency SST variability in the North Atlantic. The observed SST tripole mode has about a 12 year period and it can be reasonably reproduced by the weather noise forcing in terms of its period, spatial pattern and variance. Based on our diagnosis, it is argued that the SST tripole is mainly forced by local atmospheric heat flux noise. The gyre circulation plays a secondary role: the anomalous gyre circulation advects mean thermal features across the inter-gyre boundary, and the mean gyre advection carries SST anomalies along the inter-gyre boundary. The diagnosis is compared with a delayed oscillator theory. We find that the delayed oscillator theory is not supported and that the SST tripole mode is forced by weather noise heat flux noise. However, the result may be model dependent.

  7. Variabilities of Low-Latitude Migrating and Nonmigrating Tides in GPS-TEC and TIMED-SABER Temperature During the Sudden Stratospheric Warming Event of 2013

    NASA Astrophysics Data System (ADS)

    Sridharan, S.

    2017-10-01

    The Global Positioning System deduced total electron content (TEC) data at 15°N (geomagnetic), which is the crest region of equatorial ionization anomaly, are used to study tidal variabilities during the 2013 sudden stratospheric warming (SSW) event. The results from space-time spectral analysis reveal that the amplitudes of migrating diurnal (DW1) and semidiurnal (SW2) tides are larger than those of nonmigrating tides. After the SSW onset, the amplitudes of DW1, SW2, SW1, and DS0 increase. Moreover, they show 16 day variations similar to the periodicity of the high-latitude stratospheric planetary wave (PW), suggesting that the nonmigrating tides (SW1 and DS0) are possibly generated due to nonlinear interaction of migrating tides with PW. Similar spectral analysis on temperature at 10°N obtained from the Sounding of Atmosphere by Broadband Emission Radiometry (SABER) shows that the SW2 enhances at stratospheric heights and the SW2 is more dominant at 80-90 km, but its amplitude decreases around 100 km. The amplitudes of nonmigrating tides become comparable to those of SW2 around 100 km, and their contribution becomes increasingly important at higher heights. This suggests that the nonlinear interaction between migrating tides and PW occurs at low-latitude upper mesospheric heights, as SW2 exhibits 16 day periodicity in SABER temperature at 100 km as observed in TEC. Besides, it is observed that the eastward propagating tides are less dominant than westward propagating tides in both TEC and SABER temperatures.

  8. Intraannual variability of tides in the thermosphere from model simulations and in situ satellite observations

    NASA Astrophysics Data System (ADS)

    Häusler, K.; Hagan, M. E.; Forbes, J. M.; Zhang, X.; Doornbos, E.; Bruinsma, S.; Lu, G.

    2015-01-01

    In this paper, we provide insights into limitations imposed by current satellite-based strategies to delineate tidal variability in the thermosphere, as well as the ability of a state-of-the-art model to replicate thermospheric tidal determinations. Toward this end, we conducted a year-long thermosphere-ionosphere-mesosphere-electrodynamics general circulation model (TIME-GCM) simulation for 2009, which is characterized by low solar and geomagnetic activity. In order to account for tropospheric waves and tides propagating upward into the ˜30-400 km model domain, we used 3-hourly MERRA (Modern-Era Retrospective Analysis for Research and Application) reanalysis data. We focus on exospheric tidal temperatures, which are also compared with 72 day mean determinations from combined Challenging Minisatellite Payload (CHAMP) and Gravity Recovery and Climate Experiment (GRACE) satellite observations to assess the model's capability to capture the observed tidal signatures and to quantify the uncertainties associated with the satellite exospheric temperature determination technique. We found strong day-to-day tidal variability in TIME-GCM that is smoothed out when averaged over as few as ten days. TIME-GCM notably overestimates the 72 day mean eastward propagating tides observed by CHAMP/GRACE, while capturing many of the salient features of other tidal components. However, the CHAMP/GRACE tidal determination technique only provides a gross climatological representation, underestimates the majority of the tidal components in the climatological spectrum, and moreover fails to characterize the extreme variability that drives the dynamics and electrodynamics of the ionosphere-thermosphere system. A multisatellite mission that samples at least six local times simultaneously is needed to provide this quantification.

  9. Tropical Ocean Surface Energy Balance Variability: Linking Weather to Climate Scales

    NASA Technical Reports Server (NTRS)

    Roberts, J. Brent; Clayson, Carol Anne

    2013-01-01

    Radiative and turbulent surface exchanges of heat and moisture across the atmosphere-ocean interface are fundamental components of the Earth s energy and water balance. Characterizing the spatiotemporal variability of these exchanges of heat and moisture is critical to understanding the global water and energy cycle variations, quantifying atmosphere-ocean feedbacks, and improving model predictability. These fluxes are integral components to tropical ocean-atmosphere variability; they can drive ocean mixed layer variations and modify the atmospheric boundary layer properties including moist static stability, thereby influencing larger-scale tropical dynamics. Non-parametric cluster-based classification of atmospheric and ocean surface properties has shown an ability to identify coherent weather regimes, each typically associated with similar properties and processes. Using satellite-based observational radiative and turbulent energy flux products, this study investigates the relationship between these weather states and surface energy processes within the context of tropical climate variability. Investigations of surface energy variations accompanying intraseasonal and interannual tropical variability often use composite-based analyses of the mean quantities of interest. Here, a similar compositing technique is employed, but the focus is on the distribution of the heat and moisture fluxes within their weather regimes. Are the observed changes in surface energy components dominated by changes in the frequency of the weather regimes or through changes in the associated fluxes within those regimes? It is this question that the presented work intends to address. The distribution of the surface heat and moisture fluxes is evaluated for both normal and non-normal states. By examining both phases of the climatic oscillations, the symmetry of energy and water cycle responses are considered.

  10. Tying Variability in Summertime North American Extreme Weather Regimes to the Boreal Summer Intraseasonal Oscillation

    NASA Astrophysics Data System (ADS)

    Jenney, A. M.; Randall, D. A.

    2017-12-01

    Tropical intraseasonal oscillations are known to be a source of extratropical variability. We show that subseasonal variability in observed North American epidemiologically significant regional extreme weather regimes is teleconnected to the boreal summer intraseasonal oscillation (BSISO)—a complex tropical weather system that is active during the northern summer and has a 30-50 day timescale. The dynamics of the teleconnection are examined. We also find that interannual variability of the tropical mean-state can modulate the teleconnection. Our results suggest that the BSISO may enable subseasonal to seasonal predictions of North American summertime weather extremes.

  11. Description and assessment of regional sea-level trends and variability from altimetry and tide gauges at the northern Australian coast

    NASA Astrophysics Data System (ADS)

    Gharineiat, Zahra; Deng, Xiaoli

    2018-05-01

    This paper aims at providing a descriptive view of the low-frequency sea-level changes around the northern Australian coastline. Twenty years of sea-level observations from multi-mission satellite altimetry and tide gauges are used to characterize sea-level trends and inter-annual variability over the study region. The results show that the interannual sea-level fingerprint in the northern Australian coastline is closely related to El Niño Southern Oscillation (ENSO) and Madden-Julian Oscillation (MJO) events, with the greatest influence on the Gulf Carpentaria, Arafura Sea, and the Timor Sea. The basin average of 14 tide-gauge time series is in strong agreement with the basin average of the altimeter data, with a root mean square difference of 18 mm and a correlation coefficient of 0.95. The rate of the sea-level trend over the altimetry period (6.3 ± 1.4 mm/yr) estimated from tide gauges is slightly higher than that (6.1 ± 1.3 mm/yr) from altimetry in the time interval 1993-2013, which can vary with the length of the time interval. Here we provide new insights into examining the significance of sea-level trends by applying the non-parametric Mann-Kendall test. This test is applied to assess if the trends are significant (upward or downward). Apart from a positive rate of sea-level trends are not statistically significant in this region due to the effects of natural variability. The findings suggest that altimetric trends are not significant along the coasts and some parts of the Gulf Carpentaria (14°S-8°S), where geophysical corrections (e.g., ocean tides) cannot be estimated accurately and altimeter measurements are contaminated by reflections from the land.

  12. Preliminary Study on Coupling Wave-Tide-Storm Surges Prediction System

    NASA Astrophysics Data System (ADS)

    You, S.; Park, S.; Seo, J.; Kim, K.

    2008-12-01

    The Korean Peninsula is surrounded by the Yellow Sea, East China Sea, and East Sea. This complex oceanographic system includes large tides in the Yellow Sea and seasonally varying monsoon and typhoon events. For Korea's coastal regions, floods caused by wave and storm surges are among the most serious threats. To predict more accurate wave and storm surge, the development of coupling wave-tide-storm surges prediction system is essential. For the time being, wave and storm surges predictions are still made separately in KMA (Korea Meteorological Administration) and most operational institute. However, many researchers have emphasized the effects of tides and storm surges on wind waves and recommended further investigations into the effects of wave-tide-storm surges interactions and coupling module on wave heights. However, tidal height and current give a great effect on the wave prediction in the Yellow sea where is very high tide and related research is not enough. At present, KMA has operated the wave (RWAM : Regional Wave Model) and storm surges/tide prediction system (RTSM : Regional Tide/Storm Surges Model) for ocean forecasting. The RWAM is WAVEWATCH III which is a third generation wave model developed by Tolman (1989). The RTSM is based on POM (Princeton Ocean Model, Blumberg and Mellor, 1987). The RWAM and RTSM cover the northwestern Pacific Ocean from 115°E to 150°E and from 20°N to 52°N. The horizontal grid intervals are 1/12° in both latitudinal and longitudinal directions. The development, testing and application of a coupling module in which wave-tide-storm surges are incorporated within the frame of KMA Ocean prediction system, has been considered as a step forward in respect of ocean forecasting. In addition, advanced wave prediction model will be applicable to the effect of ocean in the weather forecasting system. The main purpose of this study is to show how the coupling module developed and to report on a series of experiments dealing with the

  13. Understanding Space Weather: The Sun as a Variable Star

    NASA Technical Reports Server (NTRS)

    Strong, Keith; Saba, Julia; Kucera, Therese

    2011-01-01

    The Sun is a complex system of systems and until recently, less than half of its surface was observable at any given time and then only from afar. New observational techniques and modeling capabilities are giving us a fresh perspective of the solar interior and how our Sun works as a variable star. This revolution in solar observations and modeling provides us with the exciting prospect of being able to use a vastly increased stream of solar data taken simultaneously from several different vantage points to produce more reliable and prompt space weather forecasts. Solar variations that cause identifiable space weather effects do not happen only on solar-cycle timescales from decades to centuries; there are also many shorter-term events that have their own unique space weather effects and a different set of challenges to understand and predict, such as flares, coronal mass ejections, and solar wind variations

  14. Understanding Space Weather: The Sun as a Variable Star

    NASA Technical Reports Server (NTRS)

    Strong, Keith; Saba, Julia; Kucera, Therese

    2012-01-01

    The Sun is a complex system of systems and until recently, less than half of its surface was observable at any given time and then only from afar. New observational techniques and modeling capabilities are giving us a fresh perspective of the solar interior and how our Sun works as a variable star. This revolution in solar observations and modeling provides us with the exciting prospect of being able to use a vastly increased stream of solar data taken simultaneously from several different vantage points to produce more reliable and prompt space weather forecasts. Solar variations that cause identifiable space weather effects do not happen only on solar-cycle timescales from decades to centuries; there are also many shorter-term events that have their own unique space weather effects and a different set of challenges to understand and predict, such as flares, coronal mass ejections, and solar wind variations.

  15. Climatology of diurnal tide and its long-term variability in the lower middle atmosphere over a tropical station

    NASA Astrophysics Data System (ADS)

    Kumar, P. Vinay; Dutta, Gopa; Mohammad, Salauddin; Rao, B. Venkateswara

    2017-10-01

    ECMWF reanalysis (ERA-interim) data of winds for two solar cycles (1991-2012) are harmonically analyzed to delineate the characteristics and variability of diurnal tide over a tropical site (13.5° N, 79.5° E). The diurnal cycle horizontal winds measured by Gadanki (13.5° N, 79.2° E) mesosphere-stratosphere-troposphere (MST) radar between May 2005 and April 2006 have been used to compute 24 h tidal amplitudes and phases and compared with the corresponding results obtained from ERA winds. The climatological diurnal tidal amplitudes and phases have been estimated from surface to ˜33 km using ERA interim data. The amplitudes and phases obtained in the present study are found to compare reasonably well with Global Scale Wave Model (GSWM-09). Diurnal tides show larger amplitudes in the lower troposphere below 5 km during summer and in the mid-stratosphere mainly during equinoctial months and early winter. Water vapor and convection in the lower troposphere are observed to play major roles in exciting 24-h tide. Correlations between diurnal amplitude and integrated water vapor and between diurnal amplitude and outgoing longwave radiation (OLR) are 0.59 and -0.34, respectively. Ozone mixing ratio correlates ( ρ = 0.66) well with diurnal amplitude and shows annual variation in the troposphere whereas semi-annual variation is observed at stratospheric heights with stronger peaks in equinoctial months. A clear annual variation of diurnal amplitude is displayed in the troposphere and interannual variability becomes prominent in the stratosphere which could be partly due to the influence of equatorial stratospheric QBO. The influence of solar activity on diurnal oscillations is found to be insignificant.

  16. Short-term nonmigrating tide variability in the mesosphere, thermosphere, and ionosphere

    NASA Astrophysics Data System (ADS)

    Pedatella, N. M.; Oberheide, J.; Sutton, E. K.; Liu, H.-L.; Anderson, J. L.; Raeder, K.

    2016-04-01

    The intraseasonal variability of the eastward propagating nonmigrating diurnal tide with zonal wave number 3 (DE3) during 2007 in the mesosphere, ionosphere, and thermosphere is investigated using a whole atmosphere model reanalysis and satellite observations. The atmospheric reanalysis is based on implementation of data assimilation in the Whole Atmosphere Community Climate Model (WACCM) using the Data Assimilation Research Testbed (DART) ensemble Kalman filter. The tidal variability in the WACCM+DART reanalysis is compared to the observed variability in the mesosphere and lower thermosphere (MLT) based on the Thermosphere Ionosphere Mesosphere Energetics Dynamics satellite Sounding of the Atmosphere using Broadband Emission Radiometry (TIMED/SABER) observations, in the ionosphere based on Constellation Observing System for Meteorology, Ionosphere, and Climate (COSMIC) observations, and in the upper thermosphere (˜475 km) based on Gravity Recovery and Climate Experiment (GRACE) neutral density observations. To obtain the short-term DE3 variability in the MLT and upper thermosphere, we apply the method of tidal deconvolution to the TIMED/SABER observations and consider the difference in the ascending and descending longitudinal wave number 4 structure in the GRACE observations. The results reveal that tidal amplitude changes of 5-10 K regularly occur on short timescales (˜10-20 days) in the MLT. Similar variability occurs in the WACCM+DART reanalysis and TIMED/SABER observations, demonstrating that the short-term variability can be captured in whole atmosphere models that employ data assimilation and in observations by the technique of tidal deconvolution. The impact of the short-term DE3 variability in the MLT on the ionosphere and thermosphere is also clearly evident in the COSMIC and GRACE observations. Analysis of the troposphere forcing in WACCM+DART and simulations of the Global Scale Wave Model (GSWM) show that the short-term DE3 variability in the MLT is

  17. Variability of the internal tide on the southern Monterey Bay continental shelf and associated bottom boundary layer sediment transport

    USGS Publications Warehouse

    Rosenberger, Kurt; Storlazzi, Curt; Cheriton, Olivia

    2016-01-01

    A 6-month deployment of instrumentation from April to October 2012 in 90 m water depth near the outer edge of the mid-shelf mud belt in southern Monterey Bay, California, reveals the importance regional upwelling on water column density structure, potentially accounting for the majority of the variability in internal tidal energy flux across the shelf. Observations consisted of time-series measurements of water-column currents, temperature and salinity, and near-bed currents and suspended matter. The internal tide accounted for 15–25% of the water-column current variance and the barotropic tide accounted for up to 35%. The subtidal flow showed remarkably little shear and was dominated by the 7–14 day band, which is associated with relaxations in the dominant equatorward winds typical of coastal California in the spring and summer. Upwelling and relaxation events resulted in strong near-bed flows and accounted for almost half of the current stress on the seafloor (not accounting for wave orbital velocities), and may have driven along-shelf geostrophic flow during steady state conditions. Several elevated suspended particulate matter (SPM) events occurred within 3 m of the bed and were generally associated with higher, long-period surface waves. However, these peaks in SPM did not coincide with the predicted resuspension events from the modeled combined wave–current shear stress, indicating that the observed SPM at our site was most likely resuspended elsewhere and advected along-isobath. Sediment flux was almost equal in magnitude in the alongshore and cross-shore directions. Instances of wave–current shear stress that exceeded the threshold of resuspension for the silty-clays common at these water depths only occurred when near-bed orbital velocities due to long-period surface waves coincided with vigorous near-bed currents associated with the internal tide or upwelling/relaxation events. Thus upwelling/relaxation dynamics are primarily responsible for

  18. Kingdom of the Tides.

    ERIC Educational Resources Information Center

    Carter, Samuel, III

    Areas of discussion are the history of tides, the forces which exert an influence upon the earth's tides, the behavior of tides as modified by terrestrial features, "freak" behavior of tides, the marine life which inhabits tidal areas, the manner in which tides have helped to shape the course of history, how tides affect our lives on a…

  19. An advanced stochastic weather generator for simulating 2-D high-resolution climate variables

    NASA Astrophysics Data System (ADS)

    Peleg, Nadav; Fatichi, Simone; Paschalis, Athanasios; Molnar, Peter; Burlando, Paolo

    2017-07-01

    A new stochastic weather generator, Advanced WEather GENerator for a two-dimensional grid (AWE-GEN-2d) is presented. The model combines physical and stochastic approaches to simulate key meteorological variables at high spatial and temporal resolution: 2 km × 2 km and 5 min for precipitation and cloud cover and 100 m × 100 m and 1 h for near-surface air temperature, solar radiation, vapor pressure, atmospheric pressure, and near-surface wind. The model requires spatially distributed data for the calibration process, which can nowadays be obtained by remote sensing devices (weather radar and satellites), reanalysis data sets and ground stations. AWE-GEN-2d is parsimonious in terms of computational demand and therefore is particularly suitable for studies where exploring internal climatic variability at multiple spatial and temporal scales is fundamental. Applications of the model include models of environmental systems, such as hydrological and geomorphological models, where high-resolution spatial and temporal meteorological forcing is crucial. The weather generator was calibrated and validated for the Engelberg region, an area with complex topography in the Swiss Alps. Model test shows that the climate variables are generated by AWE-GEN-2d with a level of accuracy that is sufficient for many practical applications.

  20. Weather variability and the incidence of cryptosporidiosis: comparison of time series poisson regression and SARIMA models.

    PubMed

    Hu, Wenbiao; Tong, Shilu; Mengersen, Kerrie; Connell, Des

    2007-09-01

    Few studies have examined the relationship between weather variables and cryptosporidiosis in Australia. This paper examines the potential impact of weather variability on the transmission of cryptosporidiosis and explores the possibility of developing an empirical forecast system. Data on weather variables, notified cryptosporidiosis cases, and population size in Brisbane were supplied by the Australian Bureau of Meteorology, Queensland Department of Health, and Australian Bureau of Statistics for the period of January 1, 1996-December 31, 2004, respectively. Time series Poisson regression and seasonal auto-regression integrated moving average (SARIMA) models were performed to examine the potential impact of weather variability on the transmission of cryptosporidiosis. Both the time series Poisson regression and SARIMA models show that seasonal and monthly maximum temperature at a prior moving average of 1 and 3 months were significantly associated with cryptosporidiosis disease. It suggests that there may be 50 more cases a year for an increase of 1 degrees C maximum temperature on average in Brisbane. Model assessments indicated that the SARIMA model had better predictive ability than the Poisson regression model (SARIMA: root mean square error (RMSE): 0.40, Akaike information criterion (AIC): -12.53; Poisson regression: RMSE: 0.54, AIC: -2.84). Furthermore, the analysis of residuals shows that the time series Poisson regression appeared to violate a modeling assumption, in that residual autocorrelation persisted. The results of this study suggest that weather variability (particularly maximum temperature) may have played a significant role in the transmission of cryptosporidiosis. A SARIMA model may be a better predictive model than a Poisson regression model in the assessment of the relationship between weather variability and the incidence of cryptosporidiosis.

  1. Weather patterns as a downscaling tool - evaluating their skill in stratifying local climate variables

    NASA Astrophysics Data System (ADS)

    Murawski, Aline; Bürger, Gerd; Vorogushyn, Sergiy; Merz, Bruno

    2016-04-01

    The use of a weather pattern based approach for downscaling of coarse, gridded atmospheric data, as usually obtained from the output of general circulation models (GCM), allows for investigating the impact of anthropogenic greenhouse gas emissions on fluxes and state variables of the hydrological cycle such as e.g. on runoff in large river catchments. Here we aim at attributing changes in high flows in the Rhine catchment to anthropogenic climate change. Therefore we run an objective classification scheme (simulated annealing and diversified randomisation - SANDRA, available from the cost733 classification software) on ERA20C reanalyses data and apply the established classification to GCMs from the CMIP5 project. After deriving weather pattern time series from GCM runs using forcing from all greenhouse gases (All-Hist) and using natural greenhouse gas forcing only (Nat-Hist), a weather generator will be employed to obtain climate data time series for the hydrological model. The parameters of the weather pattern classification (i.e. spatial extent, number of patterns, classification variables) need to be selected in a way that allows for good stratification of the meteorological variables that are of interest for the hydrological modelling. We evaluate the skill of the classification in stratifying meteorological data using a multi-variable approach. This allows for estimating the stratification skill for all meteorological variables together, not separately as usually done in existing similar work. The advantage of the multi-variable approach is to properly account for situations where e.g. two patterns are associated with similar mean daily temperature, but one pattern is dry while the other one is related to considerable amounts of precipitation. Thus, the separation of these two patterns would not be justified when considering temperature only, but is perfectly reasonable when accounting for precipitation as well. Besides that, the weather patterns derived from

  2. The inverse problem: Ocean tides derived from earth tide observations

    NASA Technical Reports Server (NTRS)

    Kuo, J. T.

    1978-01-01

    Indirect mapping ocean tides by means of land and island-based tidal gravity measurements is presented. The inverse scheme of linear programming is used for indirect mapping of ocean tides. Open ocean tides were measured by the numerical integration of Laplace's tidal equations.

  3. Structure and Variability of Internal Tides in Luzon Strait

    DTIC Science & Technology

    2016-09-14

    suggestions of outside individuals or concerns which have been communicated to the Laboratory in confidence. This paper (does ) (does not X ) contain...generated where the barotropic tides force stratified water over underwater bathymetry, are thought to provide a significant fraction of the 2 TW of energy...required to maintain abyssal stratification and the meridional overturning circulation (Munk and Wunsch 1998). They contribute to oceanmixing through a

  4. The Space Weather and Ultraviolet Solar Variability (SWUSV) Microsatellite Mission

    PubMed Central

    Damé, Luc; Meftah, Mustapha; Hauchecorne, Alain; Keckhut, Philippe; Sarkissian, Alain; Marchand, Marion; Irbah, Abdenour; Quémerais, Éric; Bekki, Slimane; Foujols, Thomas; Kretzschmar, Matthieu; Cessateur, Gaël; Shapiro, Alexander; Schmutz, Werner; Kuzin, Sergey; Slemzin, Vladimir; Urnov, Alexander; Bogachev, Sergey; Merayo, José; Brauer, Peter; Tsinganos, Kanaris; Paschalis, Antonis; Mahrous, Ayman; Khaled, Safinaz; Ghitas, Ahmed; Marzouk, Besheir; Zaki, Amal; Hady, Ahmed A.; Kariyappa, Rangaiah

    2013-01-01

    We present the ambitions of the SWUSV (Space Weather and Ultraviolet Solar Variability) Microsatellite Mission that encompasses three major scientific objectives: (1) Space Weather including the prediction and detection of major eruptions and coronal mass ejections (Lyman-Alpha and Herzberg continuum imaging); (2) solar forcing on the climate through radiation and their interactions with the local stratosphere (UV spectral irradiance from 180 to 400 nm by bands of 20 nm, plus Lyman-Alpha and the CN bandhead); (3) simultaneous radiative budget of the Earth, UV to IR, with an accuracy better than 1% in differential. The paper briefly outlines the mission and describes the five proposed instruments of the model payload: SUAVE (Solar Ultraviolet Advanced Variability Experiment), an optimized telescope for FUV (Lyman-Alpha) and MUV (200–220 nm Herzberg continuum) imaging (sources of variability); UPR (Ultraviolet Passband Radiometers), with 64 UV filter radiometers; a vector magnetometer; thermal plasma measurements and Langmuir probes; and a total and spectral solar irradiance and Earth radiative budget ensemble (SERB, Solar irradiance & Earth Radiative Budget). SWUSV is proposed as a small mission to CNES and to ESA for a possible flight as early as 2017–2018. PMID:25685424

  5. The Space Weather and Ultraviolet Solar Variability (SWUSV) Microsatellite Mission.

    PubMed

    Damé, Luc

    2013-05-01

    We present the ambitions of the SWUSV (Space Weather and Ultraviolet Solar Variability) Microsatellite Mission that encompasses three major scientific objectives: (1) Space Weather including the prediction and detection of major eruptions and coronal mass ejections (Lyman-Alpha and Herzberg continuum imaging); (2) solar forcing on the climate through radiation and their interactions with the local stratosphere (UV spectral irradiance from 180 to 400 nm by bands of 20 nm, plus Lyman-Alpha and the CN bandhead); (3) simultaneous radiative budget of the Earth, UV to IR, with an accuracy better than 1% in differential. The paper briefly outlines the mission and describes the five proposed instruments of the model payload: SUAVE (Solar Ultraviolet Advanced Variability Experiment), an optimized telescope for FUV (Lyman-Alpha) and MUV (200-220 nm Herzberg continuum) imaging (sources of variability); UPR (Ultraviolet Passband Radiometers), with 64 UV filter radiometers; a vector magnetometer; thermal plasma measurements and Langmuir probes; and a total and spectral solar irradiance and Earth radiative budget ensemble (SERB, Solar irradiance & Earth Radiative Budget). SWUSV is proposed as a small mission to CNES and to ESA for a possible flight as early as 2017-2018.

  6. The Role of Gravity Waves in Modulating Atmospheric Tides

    NASA Technical Reports Server (NTRS)

    Mayr, H. G.; Mengel, J. G; Chan, K. L.; Porter, H. S.

    1999-01-01

    We discuss results for the diurnal and semidiurnal tides obtained from our 3-D, time dependent numerical spectral model (NMS), extending from the ground up into the thermosphere, which incorporates Hines' Doppler spread parameterization of small scale gravity waves (GW). In the DSP, GW momentum (and energy) are conserved as the waves modulate the background flow and are filtered by the flow.As a consequence, the GW interaction tightly couples the dynamic components of the middle atmosphere with strong non-linear interactions between mean zonal circulation, tides and planetary waves to produce complicated patterns of variability much like those observed. The major conclusions are: (1) Since GW momentum is deposited in the altitude regime of increasing winds, the amplitude of the diurnal tide is amplified and its vertical wavelength is reduced at altitudes between 80 and 120 km. Wave filtering by the mean zonal circulation (with peak velocities during solstice) causes the GW flux to peak during equinox, and this produces a large semi-annual variation in the tide that has been observed on UARS. (2) Without the diurnal tide, the semidiurnal tide would also be modulated in this way. But the diurnal tide filters out the GW preferentially during equinox, so that the semidiurnal tide, at higher altitudes, tends to peak during solstice. (3) Under the influence of GW, the tides are modulated also significantly by planetary waves, with periods between 2 and 30 days, which are generated preferentially during solstice in part due to baroclinic instability.

  7. Seasonality in trauma admissions - Are daylight and weather variables better predictors than general cyclic effects?

    PubMed

    Røislien, Jo; Søvik, Signe; Eken, Torsten

    2018-01-01

    Trauma is a leading global cause of death, and predicting the burden of trauma admissions is vital for good planning of trauma care. Seasonality in trauma admissions has been found in several studies. Seasonal fluctuations in daylight hours, temperature and weather affect social and cultural practices but also individual neuroendocrine rhythms that may ultimately modify behaviour and potentially predispose to trauma. The aim of the present study was to explore to what extent the observed seasonality in daily trauma admissions could be explained by changes in daylight and weather variables throughout the year. Retrospective registry study on trauma admissions in the 10-year period 2001-2010 at Oslo University Hospital, Ullevål, Norway, where the amount of daylight varies from less than 6 hours to almost 19 hours per day throughout the year. Daily number of admissions was analysed by fitting non-linear Poisson time series regression models, simultaneously adjusting for several layers of temporal patterns, including a non-linear long-term trend and both seasonal and weekly cyclic effects. Five daylight and weather variables were explored, including hours of daylight and amount of precipitation. Models were compared using Akaike's Information Criterion (AIC). A regression model including daylight and weather variables significantly outperformed a traditional seasonality model in terms of AIC. A cyclic week effect was significant in all models. Daylight and weather variables are better predictors of seasonality in daily trauma admissions than mere information on day-of-year.

  8. Perigean Spring Tides and Apogean Neap Tides in History

    NASA Astrophysics Data System (ADS)

    Olson, Donald W.

    2012-01-01

    On January 4, 1912 - almost exactly 100 years ago - both a full Moon and a lunar perigee occurred, with these two events separated by only a few minutes of time and with the Earth near perihelion. The resulting lunar distance (356,375 km) on that date stands as the closest approach of the Moon to the Earth in an interval of more than 1400 years. The centennial of this extreme lunar perigee is an appropriate time to consider the effect of lunar distance on the range of ocean tides. At most ocean ports, spring tides of increased range occur near new and full Moon. If a lunar perigee falls near new or full Moon, then perigean spring tides of even greater range are possible. Conversely, if a lunar apogee falls near first quarter or last quarter Moon, then apogean neap tides of unusually reduced range can occur. Examples of perigean spring tides include a near-coincidence of lunar perigee and new Moon in December 1340 that may be related to a plot device in Chaucer's "The Franklin's Tale,” a Canterbury tale that describes an extreme high tide covering the rocks on the coast of Brittany in "the cold and frosty season of December.” Another example, the disaster known as the Bristol Channel Flood, occurred shortly after a lunar perigee and new Moon in January 1607. A German U-boat employed an exceptionally high perigean spring tide shortly after the new Moon of October 1939 to enter Scapa Flow by an unexpected route and sink the HMS Royal Oak. An apogean neap tide prevailed during the amphibious assault of the U. S. Marines at Tarawa in November 1943, making the eventual victory more costly because the landing craft were unable to reach the island and instead grounded on the surrounding reef.

  9. The role of synoptic weather variability in Greenland ice sheet dynamics

    NASA Astrophysics Data System (ADS)

    Walker, J. M.; Radic, V.

    2017-12-01

    Much of the large uncertainty in predictions of future global sea level rise is due to our limited understanding of Greenland ice sheet (GrIS) motion and its interactions with climate. Over the next century, climate models predict that the GrIS will experience not only gradual warming, but also changes in atmospheric circulation, hydrology, and weather, including a northward shift of the North Atlantic storm track, with greater frequency and intensity of rain storms over the GrIS. Recent studies of GrIS dynamics have focused on the effects of increased seasonal mean meltwater on ice velocities, finding only a modest impact due to compensation by subglacial drainage systems, but subglacial hydraulic theory indicates that variability on shorter timescales is also relevant: short-term surges in meltwater or rainfall can overload drainage systems at rates faster than they can adjust, leading to water pressure spikes and ice acceleration. If the magnitude or frequency of these transient ice accelerations increase substantially as synoptic weather patterns change over the next century, there could be a significant cumulative impact on seasonal mean ice velocities. However, this issue has not been addressed in the literature and represents a major source of uncertainty. In this study, we investigate the role of synoptic weather variability in GrIS dynamics, with the ultimate goal of evaluating the relationships between extreme weather events and ice sheet flow in different seasons and regions of the GrIS. As a first step, we apply the machine learning technique of self-organizing maps to atmospheric reanalysis data to categorize the predominant synoptic weather systems over the GrIS domain, evaluating atmospheric moisture transport and rainfall to assess the impacts of each weather system on GrIS surface hydrology. The preliminary results presented here will be used in conjunction with ice velocity satellite measurements in future work, to identify any correlations

  10. Simulating soybean canopy temperature as affected by weather variables and soil water potential

    NASA Technical Reports Server (NTRS)

    Choudhury, B. J.

    1982-01-01

    Hourly weather data for several clear sky days during summer at Phoenix and Baltimore which covered a wide range of variables were used with a plant atmosphere model to simulate soybean (Glycine max L.) leaf water potential, stomatal resistance and canopy temperature at various soil water potentials. The air and dew point temperatures were found to be the significant weather variables affecting the canopy temperatures. Under identical weather conditions, the model gives a lower canopy temperature for a soybean crop with a higher rooting density. A knowledge of crop rooting density, in addition to air and dew point temperatures is needed in interpreting infrared radiometric observations for soil water status. The observed dependence of stomatal resistance on the vapor pressure deficit and soil water potential is fairly well represented. Analysis of the simulated leaf water potentials indicates overestimation, possibly due to differences in the cultivars.

  11. Sensitivity Analysis of Weather Variables on Offsite Consequence Analysis Tools in South Korea and the United States.

    PubMed

    Kim, Min-Uk; Moon, Kyong Whan; Sohn, Jong-Ryeul; Byeon, Sang-Hoon

    2018-05-18

    We studied sensitive weather variables for consequence analysis, in the case of chemical leaks on the user side of offsite consequence analysis (OCA) tools. We used OCA tools Korea Offsite Risk Assessment (KORA) and Areal Location of Hazardous Atmospheres (ALOHA) in South Korea and the United States, respectively. The chemicals used for this analysis were 28% ammonia (NH₃), 35% hydrogen chloride (HCl), 50% hydrofluoric acid (HF), and 69% nitric acid (HNO₃). The accident scenarios were based on leakage accidents in storage tanks. The weather variables were air temperature, wind speed, humidity, and atmospheric stability. Sensitivity analysis was performed using the Statistical Package for the Social Sciences (SPSS) program for dummy regression analysis. Sensitivity analysis showed that impact distance was not sensitive to humidity. Impact distance was most sensitive to atmospheric stability, and was also more sensitive to air temperature than wind speed, according to both the KORA and ALOHA tools. Moreover, the weather variables were more sensitive in rural conditions than in urban conditions, with the ALOHA tool being more influenced by weather variables than the KORA tool. Therefore, if using the ALOHA tool instead of the KORA tool in rural conditions, users should be careful not to cause any differences in impact distance due to input errors of weather variables, with the most sensitive one being atmospheric stability.

  12. Kilometric Scale Modeling of the North West European Shelf Seas: Exploring the Spatial and Temporal Variability of Internal Tides

    NASA Astrophysics Data System (ADS)

    Guihou, K.; Polton, J.; Harle, J.; Wakelin, S.; O'Dea, E.; Holt, J.

    2018-01-01

    The North West European Shelf break acts as a barrier to the transport and exchange between the open ocean and the shelf seas. The strong spatial variability of these exchange processes is hard to fully explore using observations, and simulations generally are too coarse to simulate the fine-scale processes over the whole region. In this context, under the FASTNEt program, a new NEMO configuration of the North West European Shelf and Atlantic Margin at 1/60° (˜1.8 km) has been developed, with the objective to better understand and quantify the seasonal and interannual variability of shelf break processes. The capability of this configuration to reproduce the seasonal cycle in SST, the barotropic tide, and fine-resolution temperature profiles is assessed against a basin-scale (1/12°, ˜9 km) configuration and a standard regional configuration (7 km resolution). The seasonal cycle is well reproduced in all configurations though the fine-resolution allows the simulation of smaller scale processes. Time series of temperature at various locations on the shelf show the presence of internal waves with a strong spatiotemporal variability. Spectral analysis of the internal waves reveals peaks at the diurnal, semidiurnal, inertial, and quarter-diurnal bands, which are only realistically reproduced in the new configuration. Tidally induced pycnocline variability is diagnosed in the model and shown to vary with the spring neap cycle with mean displacement amplitudes in excess of 2 m for 30% of the stratified domain. With sufficiently fine resolution, internal tides are shown to be generated at numerous bathymetric features resulting in a complex pycnocline displacement superposition pattern.

  13. A tide prediction and tide height control system for laboratory mesocosms

    PubMed Central

    Long, Jeremy D.

    2015-01-01

    Experimental mesocosm studies of rocky shore and estuarine intertidal systems may benefit from the application of natural tide cycles to better replicate variation in immersion time, water depth, and attendant fluctuations in abiotic and edaphic conditions. Here we describe a stand-alone microcontroller tide prediction open-source software program, coupled with a mechanical tidal elevation control system, which allows continuous adjustment of aquarium water depths in synchrony with local tide cycles. We used this system to monitor the growth of Spartina foliosa marsh cordgrass and scale insect herbivores at three simulated shore elevations in laboratory mesocosms. Plant growth decreased with increasing shore elevation, while scale insect population growth on the plants was not strongly affected by immersion time. This system shows promise for a range of laboratory mesocosm studies where natural tide cycling could impact organism performance or behavior, while the tide prediction system could additionally be utilized in field experiments where treatments need to be applied at certain stages of the tide cycle. PMID:26623195

  14. Electrodynamics of ionospheric weather over low latitudes

    NASA Astrophysics Data System (ADS)

    Abdu, Mangalathayil Ali

    2016-12-01

    The dynamic state of the ionosphere at low latitudes is largely controlled by electric fields originating from dynamo actions by atmospheric waves propagating from below and the solar wind-magnetosphere interaction from above. These electric fields cause structuring of the ionosphere in wide ranging spatial and temporal scales that impact on space-based communication and navigation systems constituting an important segment of our technology-based day-to-day lives. The largest of the ionosphere structures, the equatorial ionization anomaly, with global maximum of plasma densities can cause propagation delays on the GNSS signals. The sunset electrodynamics is responsible for the generation of plasma bubble wide spectrum irregularities that can cause scintillation or even disruptions of satellite communication/navigation signals. Driven basically by upward propagating tides, these electric fields can suffer significant modulations from perturbation winds due to gravity waves, planetary/Kelvin waves, and non-migrating tides, as recent observational and modeling results have demonstrated. The changing state of the plasma distribution arising from these highly variable electric fields constitutes an important component of the ionospheric weather disturbances. Another, often dominating, component arises from solar disturbances when coronal mass ejection (CME) interaction with the earth's magnetosphere results in energy transport to low latitudes in the form of storm time prompt penetration electric fields and thermospheric disturbance winds. As a result, drastic modifications can occur in the form of layer restructuring (Es-, F3 layers etc.), large total electron content (TEC) enhancements, equatorial ionization anomaly (EIA) latitudinal expansion/contraction, anomalous polarization electric fields/vertical drifts, enhanced growth/suppression of plasma structuring, etc. A brief review of our current understanding of the ionospheric weather variations and the

  15. Relative roles of weather variables and change in human population in malaria: comparison over different states of India.

    PubMed

    Goswami, Prashant; Murty, Upadhayula Suryanarayana; Mutheneni, Srinivasa Rao; Krishnan, Swathi Trithala

    2014-01-01

    Pro-active and effective control as well as quantitative assessment of impact of climate change on malaria requires identification of the major drivers of the epidemic. Malaria depends on vector abundance which, in turn, depends on a combination of weather variables. However, there remain several gaps in our understanding and assessment of malaria in a changing climate. Most of the studies have considered weekly or even monthly mean values of weather variables, while the malaria vector is sensitive to daily variations. Secondly, rarely all the relevant meteorological variables have been considered together. An important question is the relative roles of weather variables (vector abundance) and change in host (human) population, in the change in disease load. We consider the 28 states of India, characterized by diverse climatic zones and changing population as well as complex variability in malaria, as a natural test bed. An annual vector load for each of the 28 states is defined based on the number of vector genesis days computed using daily values of temperature, rainfall and humidity from NCEP daily Reanalysis; a prediction of potential malaria load is defined by taking into consideration changes in the human population and compared with the reported number of malaria cases. For most states, the number of malaria cases is very well correlated with the vector load calculated with the combined conditions of daily values of temperature, rainfall and humidity; no single weather variable has any significant association with the observed disease prevalence. The association between vector-load and daily values of weather variables is robust and holds for different climatic regions (states of India). Thus use of all the three weather variables provides a reliable means of pro-active and efficient vector sanitation and control as well as assessment of impact of climate change on malaria.

  16. Relative Roles of Weather Variables and Change in Human Population in Malaria: Comparison over Different States of India

    PubMed Central

    Goswami, Prashant; Murty, Upadhayula Suryanarayana; Mutheneni, Srinivasa Rao; Krishnan, Swathi Trithala

    2014-01-01

    Background Pro-active and effective control as well as quantitative assessment of impact of climate change on malaria requires identification of the major drivers of the epidemic. Malaria depends on vector abundance which, in turn, depends on a combination of weather variables. However, there remain several gaps in our understanding and assessment of malaria in a changing climate. Most of the studies have considered weekly or even monthly mean values of weather variables, while the malaria vector is sensitive to daily variations. Secondly, rarely all the relevant meteorological variables have been considered together. An important question is the relative roles of weather variables (vector abundance) and change in host (human) population, in the change in disease load. Method We consider the 28 states of India, characterized by diverse climatic zones and changing population as well as complex variability in malaria, as a natural test bed. An annual vector load for each of the 28 states is defined based on the number of vector genesis days computed using daily values of temperature, rainfall and humidity from NCEP daily Reanalysis; a prediction of potential malaria load is defined by taking into consideration changes in the human population and compared with the reported number of malaria cases. Results For most states, the number of malaria cases is very well correlated with the vector load calculated with the combined conditions of daily values of temperature, rainfall and humidity; no single weather variable has any significant association with the observed disease prevalence. Conclusion The association between vector-load and daily values of weather variables is robust and holds for different climatic regions (states of India). Thus use of all the three weather variables provides a reliable means of pro-active and efficient vector sanitation and control as well as assessment of impact of climate change on malaria. PMID:24971510

  17. Physical activity levels of older community-dwelling adults are influenced by summer weather variables.

    PubMed

    Brandon, Caitlin A; Gill, Dawn P; Speechley, Mark; Gilliland, Jason; Jones, Gareth R

    2009-04-01

    Adequate daily physical activity (PA) is important for maintaining functional capacity and independence in older adults. However, most older adults in Canada do not engage in enough PA to sustain fitness and functional independence. Environmental influences, such as warmer daytime temperatures, may influence PA participation; however, few studies have examined the effect of summertime temperatures on PA levels in older adults. This investigation measured the influence of summertime weather variables on PA in 48 community-dwelling older adults who were randomly recruited from a local seniors' community centre. Each participant wore an accelerometer for a single 7-consecutive-day period (between 30 May and 9 August 2006) during waking hours, and completed a PA logbook to remark on major daily PA events. Local weather variables were collected from a national weather service and compared with PA counts per minute. Regression analysis revealed a curvilinear relationship between log-transformed PA and mean daily temperature (r2 = 0.025; p < 0.05). Linear mixed effects models that accounted for repeated measures nested within individuals were performed for monthly periods, meteorological variables, sex, age, and estimated maximal oxygen consumption, with PA as the dependent variable. Age and Air Quality Index remained significant variables within the model. Higher fitness levels had no effect on allowing individuals to perform more vigorous PA in warmer temperatures.

  18. QBO Generated Inter-annual Variations of the Diurnal Tide in the Mesosphere

    NASA Technical Reports Server (NTRS)

    Mayr, Hans G.; Mengel, John G.

    2004-01-01

    We report results from a study with the Numerical Spectral Model (NSM), which produces in the mesosphere significant inter-annual variations in the diurnal tide. Applying Hines Doppler Spread Parameterization (DPS), small-scale gravity waves (GW) drive the Quasi-biennial Oscillation (QBO) and Semi-annual Oscillation (SAO). With a GW source that peaks at the equator and is taken to be isotropic and independent of season, the NSM generates near the equator a QBO with variable periods around 27 months and zonal wind amplitudes close to 20 m / s at 30 Ism. As reported earlier, the NSM reproduces the observed equinoctial maxima in the diurnal tide at altitudes around 95 km. In the present paper it is shown that the QBO modulates the tide such that the seasonal amplitude maxima can vary from one year to another by as much as 30%. Since the period of the QBO is variable, its phase relative to the seasonal cycle changes. The magnitude of the QBO modulation of the tide thus varies considerably as our long-term model simulation shows. To shed light on the underlying mechanism, the relative importance of the linearized advection terms are discussed that involve the meridional and vertical winds of the diurnal tide.

  19. QBO Generated Inter-annual Variations of the Diurnal Tide in the Mesosphere

    NASA Technical Reports Server (NTRS)

    Mayr, Hans G.; Mengel, John G.

    2004-01-01

    We report results from a study with the Numerical Spectral Model (NSM), which produces in the d i d tide significant inter-annual variations. Applying Hines' Doppler Spread Parameterization (DPS), small-scale gravity waves (GW) drive the Quasi-biennial Oscillation (QBO) and Semi-annual Oscillation (SAO). With a GW source that peaks at the equator and is taken to be isotropic and independent of season, the NSM generates a QBO with variable periods around 27 months and zonal wind amplitudes close to 20 m/s at 30 lan, As reported earlier, the NSM reproduces the observed equinoctial maxima in the diurnal tide at altitudes around 95 km. In the present paper it is shown that the QBO modulates the tide such that the seasonal amplitude maxima can vary from one year to another by as much as 30%. Since the period of the QBO is variable, its phase relative to the seasonal cycle changes. The magnitude of the QBO modulation of the tide thus varies considerably as our long-term model simulation shows. To shed light on the underlying mechanisms, we discuss (a) the relative importance of the linearized advection terms that involve the meridional and vertical winds of the diurnal tide and (b) the effects momentum deposition from GWs filtered by the QBO.

  20. Modeling Storm-Influenced Suspended Particulate Matter Flocculation Using a Tide-Wave-Combined Biomineral Model.

    PubMed

    Chen, Peihung; Yu, Jason C S; Fettweis, Michael

    2018-03-01

      Flocculation of suspended particulate matter (SPM) in marine and estuarine environments is a complex process that is influenced by physical, biological, and chemical mechanisms. The flocculation model of Maggi (2009) was adapted to simulate flocculation under various weather conditions and during different seasons. The adaptation incorporated the effect of tide-wave-combined turbulence on floc dynamics. The model was validated using in situ measurements of floc size and SPM concentration from the southern North Sea during both calm and storm conditions. The results show that tide-wave-combined turbulence needs to be incorporated when simulating flocculation in a tide-wave-dominated environment. The observed seasonal variations in floc size (Fettweis et al., 2014) were reproduced using varying values for various floc strengths in different seasons. The results revealed that the biological effect on floc strength, which enhances aggregation, is stronger during summer, indicating that floc strength in the model should be varied seasonally.

  1. Analysis of migrating diurnal tides detected in FORMOSAT-3/COSMIC temperature data

    NASA Astrophysics Data System (ADS)

    Pirscher, B.; Foelsche, U.; Borsche, M.; Kirchengast, G.; Kuo, Y.-H.

    2010-07-01

    The characteristics of atmospheric tides in the upper troposphere and lower stratosphere region are investigated using radio occultation (RO) measurements performed by the Formosa Satellite Mission-3/Constellation Observing System for Meteorology, Ionosphere, and Climate (FORMOSAT-3/COSMIC) satellite constellation and compared to tides observed in short-term forecast model fields of European Centre for Medium-Range Weather Forecasts (ECMWF) and National Centers for Environmental Prediction (NCEP). Spectral analysis of 2 years of monthly data (2007 to 2008) yields the migrating diurnal tide to be the largest spectral component. This diurnal tide shows similar temporal, latitudinal, and altitudinal characteristics in all data sets equatorward of 50°. Beyond 50°, COSMIC local time sampling is insufficient within 1 month, which prevents space-time spectral analysis from isolating atmospheric waves. Diurnal tides of temperature are characterized by largest amplitudes in the tropics (0.8 K to 1.0 K at an altitude of 30 km). Amplitudes of diurnal tides analyzed in model data are more pronounced by ˜20%. An annual cycle of the amplitudes, characteristically linked to the movement of the intertropical convergence zone, is clearly revealed. Tropical diurnal phase features downward progression of waves fronts with a vertical wavelength of 20 km. Extratropical diurnal tides are most pronounced in the model data sets with amplitudes of up to 0.5 K at 30 km. In this analysis we also see the influence of high-altitude initialization of RO data by background information in using data processed by two different centers (University Corporation for Atmospheric Research (UCAR) and Wegener Center (WEGC)). UCAR data, initialized by a climatology without tidal information, exhibit no appreciable extratropical diurnal tides, while WEGC data, initialized by ECMWF forecasts, show more pronounced ones. Overall the results underpin the utility of the local-time resolving COSMIC RO

  2. What Causes Tides?

    ERIC Educational Resources Information Center

    Donovan, Deborah

    2004-01-01

    The phenomenon of tides has a faraway source. This rise and fall of the water level over a period of several hours is a result of the gravitational pull of the Moon and the Sun on Earth's oceans. Tides exhibit predictable cycles on daily, monthly, and yearly scales. The magnitude of the tides is dependent on the position of the Earth and Moon in…

  3. Secular Changes in the Solar Semidiurnal Tide of the Western North Atlantic Ocean

    NASA Technical Reports Server (NTRS)

    Ray, Richard D.

    2009-01-01

    An analysis of twentieth century tide gauge records reveals that the solar semidiurnal tide S, has been decreasing in amplitude along the eastern coast of North America and at the mid-ocean site Bermuda. In relative terms the observed rates are unusually large, of order 10% per century. Periods of greatest change, however, are inconsistent among the stations, and roughly half the stations show increasing amplitude since the late 1990s. Excepting the Gulf of Maine, lunar tides are either static or slightly increasing in amplitude; a few stations show decreases. Large changes in solar, but not lunar, tides suggest causes related to variable radiational forcing, but the hypothesis is at present unproven. Citation: Ray, R. D. (2009), Secular changes in the solar semidiurnal tide of the western North Atlantic Ocean

  4. Waves: Internal Tides

    NASA Technical Reports Server (NTRS)

    Ray, Richard D.

    1999-01-01

    Oceanic internal tides are internal waves with tidal periodicities. They are ubiquitous throughout the ocean, although generally more pronounced near large bathymetric features such as mid-ocean ridges and continental slopes. The internal vertical displacements associated with these waves can be extraordinarily large. Near some shelf breaks where the surface tides are strong, internal displacements (e.g., of an isothermal surface) can exceed 200 meters. Displacements of 10 meters in the open ocean are not uncommon. The associated current velocities are usually comparable to or larger than the currents of the surface tide. On continental shelves internal tides can occasionally generate packets of internal solitons, which are detectable in remote sensing imagery. Other common nonlinear features are generation of higher harmonics (e.g., 6-hr waves) and wave breaking. Internal tides are known to be an important energy source for mixing of shelf waters. Recent research suggests that they may also be a significant energy source for deep-ocean mixing.

  5. Influence of synoptic weather patterns on solar irradiance variability in Europe

    NASA Astrophysics Data System (ADS)

    Parding, Kajsa; Hinkelman, Laura; Liepert, Beate; Ackerman, Thomas; Dagestad, Knut-Frode; Asle Olseth, Jan

    2014-05-01

    Solar radiation is important for many aspects of existence on Earth, including the biosphere, the hydrological cycle, and creatures living on the planet. Previous studies have reported decadal trends in observational records of surface shortwave (SW) irradiance around the world, too strong to be caused by varying solar output. These observed decadal trends have been dubbed "solar dimming and brightening" and are believed to be related to changes in atmospheric aerosols and cloud cover. Because the observed solar variability coincides with qualitative air pollution histories, the dimming and brightening have become almost synonymous with shortwave attenuation by anthropogenic aerosols. However, there are indications that atmospheric circulation patterns have influenced the dimming and brightening in some regions, e.g., Alaska and Scandinavia. In this work, we focus on the role of atmospheric circulation patterns in modifying shortwave irradiance. An examination of European SW irradiance data from the Global Energy Balance Archive (GEBA) shows that while there are periods of predominantly decreasing (~1970-1985) and increasing (~1985-2007) SW irradiance, the changes are not spatially uniform within Europe and in a majority of locations not statistically significant. To establish a connection between weather patterns and sunshine, regression models of SW irradiance are fitted using a daily classification of European weather called Grosswetterlagen (GWL). The GWL reconstructions of shortwave irradiance represent the part of the solar variability that is related to large scale weather patterns, which should be effectively separated from the influence of varying anthropogenic aerosol emissions. The correlation (R) between observed and reconstruced SW irradiance is between 0.31 and 0.75, depending on station and season, all statistically significant (p<0.05, estimated with a bootstrap test). In central and eastern parts of Europe, the observed decadal SW variability is

  6. Do weather changes influence pain levels in women with fibromyalgia, and can psychosocial variables moderate these influences?

    NASA Astrophysics Data System (ADS)

    Smedslund, Geir; Eide, Hilde; Kristjansdottir, Ólöf Birna; Nes, Andrea Aparecida Gonçalves; Sexton, Harold; Fors, Egil A.

    2014-09-01

    The aim of this study was to examine the association between fibromyalgia pain and weather, and to investigate whether psychosocial factors influence this relationship. Women with chronic widespread pain/fibromyalgia ( N = 50) enrolled in a larger study, were recruited from a 4-week inpatient rehabilitation program in Norway ( 2009-2010), and reported their pain and psychological factors up to three times per day (morning, afternoon, evening) for 5 weeks. These ratings were then related to the official local weather parameters. Barometric pressure recorded simultaneously impacted pain significantly while temperature, relative humidity, and solar flux did not. No psychological variables influenced the weather-pain interaction. No weather parameter predicted change in the subsequent pain measures. The magnitude of the inverse association between pain and barometric pressure was very small, and none of the psychological variables studied influenced the association between pain and barometric pressure. All in all, the evidence for a strong weather-pain association in fibromyalgia seems limited at best.

  7. The link between eddy-driven jet variability and weather regimes in the North Atlantic-European sector

    NASA Astrophysics Data System (ADS)

    Madonna, E.; Li, C.; Grams, C. M.; Woollings, T.

    2017-12-01

    Understanding the variability of the North Atlantic eddy-driven jet is key to unravelling the dynamics, predictability and climate change response of extratropical weather in the region. This study aims to 1) reconcile two perspectives on wintertime variability in the North Atlantic-European sector and 2) clarify their link to atmospheric blocking. Two common views of wintertime variability in the North Atlantic are the zonal-mean framework comprising three preferred locations of the eddy-driven jet (southern, central, northern), and the weather regime framework comprising four classical North Atlantic-European regimes (Atlantic ridge AR, zonal ZO, European/Scandinavian blocking BL, Greenland anticyclone GA). We use a k-means clustering algorithm to characterize the two-dimensional variability of the eddy-driven jet stream, defined by the lower tropospheric zonal wind in the ERA-Interim reanalysis. The first three clusters capture the central jet and northern jet, along with a new mixed jet configuration; a fourth cluster is needed to recover the southern jet. The mixed cluster represents a split or strongly tilted jet, neither of which is well described in the zonal-mean framework, and has a persistence of about one week, similar to the other clusters. Connections between the preferred jet locations and weather regimes are corroborated - southern to GA, central to ZO, and northern to AR. In addition, the new mixed cluster is found to be linked to European/Scandinavian blocking, whose relation to the eddy-driven jet was previously unclear. The results highlight the necessity of bridging from weather to climate scales for a deeper understanding of atmospheric circulation variability.

  8. WEATHER RELATED VARIABILITY OF CALORIMETERY PERFORMANCE IN A POORLY CONTROLLED ENVIRONMENT

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    CAMERON, M.A.

    2007-04-16

    Four Antech airbath calorimeters at the Hanford site were studied for three summers and two winters in a location not well-shielded from outside temperature changes. All calorimeters showed significant increases in variability of standard measurements during hot weather. The increased variability is postulated to be due to a low setting of the Peltier cold face temperature, which doesn't allow the instrument to drain heat fast enough in a hot environment. A higher setting of the Peltier cold face might lead to better performance in environments subjected to a broad range of temperatures.

  9. WEATHER RELATED VARIABILITY OF CALORIMETERY PERFORMANCE IN A POORLY CONTROLLED ENVIRONMENT

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    CAMERON, M.A.

    2007-04-16

    Four Antech airbath calorimeters at the Hanford site were studied for three summers and two winters in a location not well-shielded from outside temperature changes. Calorimeters showed significant increases in variability of standard measurements during hot weather. The increased variability is postulated to be due to a low setting of the Peltier cold face temperature, which doesn't allow the instrument to drain heat fast enough in a hot environment. A higher setting of the Peltier cold face might lead to better performance in environments subjected to a broad range of temperatures.

  10. A Bayesian hierarchical model with spatial variable selection: the effect of weather on insurance claims

    PubMed Central

    Scheel, Ida; Ferkingstad, Egil; Frigessi, Arnoldo; Haug, Ola; Hinnerichsen, Mikkel; Meze-Hausken, Elisabeth

    2013-01-01

    Climate change will affect the insurance industry. We develop a Bayesian hierarchical statistical approach to explain and predict insurance losses due to weather events at a local geographic scale. The number of weather-related insurance claims is modelled by combining generalized linear models with spatially smoothed variable selection. Using Gibbs sampling and reversible jump Markov chain Monte Carlo methods, this model is fitted on daily weather and insurance data from each of the 319 municipalities which constitute southern and central Norway for the period 1997–2006. Precise out-of-sample predictions validate the model. Our results show interesting regional patterns in the effect of different weather covariates. In addition to being useful for insurance pricing, our model can be used for short-term predictions based on weather forecasts and for long-term predictions based on downscaled climate models. PMID:23396890

  11. Tides and tsunamis

    NASA Technical Reports Server (NTRS)

    Zetler, B. D.

    1972-01-01

    Although tides and tsunamis are both shallow water waves, it does not follow that they are equally amenable to an observational program using an orbiting altimeter on a satellite. A numerical feasibility investigation using a hypothetical satellite orbit, real tide observations, and sequentially increased levels of white noise has been conducted to study the degradation of the tidal harmonic constants caused by adding noise to the tide data. Tsunami waves, possibly a foot high and one hundred miles long, must be measured in individual orbits, thus requiring high relative resolution.

  12. Nutrient and chlorophyll a anomaly in red-tide periods of 2003-2008 in Sishili Bay, China

    NASA Astrophysics Data System (ADS)

    Hao, Yanju; Tang, Danling; Yu, Long; Xing, Qianguo

    2011-05-01

    Sishili Bay is the most important aquiculture and tourism area for the city of Yantai, China; however, red tides occurred frequently and have caused huge economic losses in this bay in recent years. To gain a better understanding of the local ecological environments in the bay, we conducted this research between 2003 and 2008 to analyze variations in nutrients and chlorophyll (chl- a) during high frequency red tide period (May to September). The results show that the chl- a concentration increased from 2.70 in 2003 to 7.26 mg/m3 in 2008, while the concentration of total inorganic nitrogen (TIN) and silicate (SiO3-Si) increased lineally from 5.18 and 1.45 μmol/L in 2003 to 18.57 and 9.52 μmol/L in 2008, respectively, and the annual phosphate (PO4-P) varied between 0.15 and 0.46 μmol/L. Special attention was given to a red tide in August 2007 occurred when water temperature was high and nutrient concentrations increased sharply because of a heavy rainfall. Overall, the results show the P limitation in Sishili Bay, and reveal that red tides were caused by eutrophication from terrestrial inputs and local warm weather, particularly during rainy periods. Therefore, to control red tide, greater efforts should be made to reduce sewage discharges into Sishili Bay, particularly during rainfall seasons.

  13. Population dynamics of red tide dinoflagellates

    NASA Astrophysics Data System (ADS)

    Wyatt, Timothy; Zingone, Adriana

    2014-03-01

    Sea-surface discolorations due to high concentrations of phytoplankton are called red tides. Their ecological significance is a long standing puzzle, and they are sometimes considered pathological. Here we propose that many red tides, particularly but not exclusively those composed of certain autotrophic dinoflagellates, are presexual/sexual swarms, essential links in their complex life cycles. This view provides a rationale for the appearance of these organisms in thin surface layers, and helps explain their ephemeral nature. We suggest that further understanding of this phenomenon, and of phytoplankton ecology in general, would benefit from attention to the 'net reproductive value‧ (r) over the whole life cycle as well as to the division rate (μ) of the vegetative phase. It is argued that r is strategically adapted to seasonal cycles and long term environmental variability, while μ reflects tactical needs (timing) and constraints (grazers, parasites) on vegetative growth.

  14. Jamaica Bay studies III: Abiotic determinants of distribution and abundance of gulls ( Larus)

    NASA Astrophysics Data System (ADS)

    Burger, Joanna

    1983-02-01

    The distribution and abundance of gulls were examined at Jamaica Bay Wildlife Refuge (New York) from 31 May 1978 to 31 May 1979. Gulls were found to be affected by tidal, temporal and weather-related factors. The distribution of gulls was affected primarily by tidal factors on the bay, and by temporal (seasonal, circadian) and weather-related factors on the freshwater ponds. The most important weather-related factors were temperature, wind velocity and wind direction. Herring ( L. argentatus), great black-backed ( L. fuscus) and ring-billed gulls ( L. delawarensis) fed on the bay at low tides, and used the ponds at high tide. Laughing gulls ( L. atricilla) fed on the bay at low tide and on rising tides. Herring and great black-backed gulls were present all year, but were most abundant in the winter, ring-billed gulls were abundant in spring and early fall, and laughing gulls were present in the summer following the breeding season but were absent in winter. Gulls used the ponds during high velocity, north winds, when they usually rested or preened. Multiple regression models were used to determine the factors explaining the variability in the numbers of gulls. Temporal variables were important contributors to accounting for the variability in the numbers of great black-backed and herring gulls only; tidal variables were significant for great black-backed and herring gulls on the bay, and for ring-billed and laughing gulls on all areas; and weather variables were significant for all species.

  15. Spatio-temporal atmospheric circulation variability around the Antarctic Peninsula based on hemispheric circulation modes and weather types

    NASA Astrophysics Data System (ADS)

    Wachter, Paul; Beck, Christoph; Philipp, Andreas; Jacobeit, Jucundus; Höppner, Kathrin

    2017-04-01

    Large parts of the Polar Regions are affected by a warming trend associated with substantial changes in the cryosphere. In Antarctica this positive trend pattern is most dominant in the western part of the continent and on the Antarctic Peninsula (AP). An important driving mechanism of temperature variability and trends in this region is the atmospheric circulation. Changes in atmospheric circulation modes and frequencies of circulation types have major impacts on temperature characteristics at a certain station or region. We present results of a statistical downscaling study focused on AP temperature variability showing both results of large-scale atmospheric circulation modes and regional weather type classifications derived from monthly and daily gridded reanalysis data sets. In order to investigate spatial trends and variabilities of the Southern Annular Mode (SAM), we analyze spatio-temporally resolved SAM-pattern maps from 1979 to 2015. First results show dominant multi-annual to decadal pattern variabilities which can be directly linked to temperature variabilities at the Antarctic Peninsula. A sub-continental to regional view on the influence of atmospheric circulation on AP temperature variability is given by the analysis of weather type classifications (WTC). With this analysis we identify significant changes in the frequency of occurrence of highly temperature-relevant circulation patterns. The investigated characteristics of weather type frequencies can also be related to the identified changes of the SAM.

  16. Modeling tides and their influence on the circulation in Prince William Sound, Alaska

    NASA Astrophysics Data System (ADS)

    Wang, Xiaochun; Chao, Yi; Zhang, Hongchun; Farrara, John; Li, Zhijin; Jin, Xin; Park, Kyungeen; Colas, Francois; McWilliams, James C.; Paternostro, Chris; Shum, C. K.; Yi, Yuchan; Schoch, Carl; Olsson, Peter

    2013-07-01

    In the process of developing a real-time data-assimilating coastal ocean forecasting system for Prince William Sound, Alaska, tidal signal was added to a three-domain nested model for the region. The model, which is configured from the Regional Ocean Modeling System (ROMS), has 40 levels in the vertical direction and horizontal resolutions of 10.6km, 3.6km and 1.2km for its three nested domains, respectively. In the present research, the ROMS tidal solution was validated using data from coastal tide gauges, satellite altimeters, high-frequency coastal radars, and Acoustic Doppler Current Profiler (ADCP) current surveys. The error of barotropic tides, as measured by the total root mean square discrepancy of eight major tidal constituents is 5.3cm, or 5.6% of the tidal sea surface height variability in the open ocean. Along the coastal region, the total discrepancy is 9.6cm, or 8.2% of the tidal sea surface height variability. Model tidal currents agree reasonably well with the observations. The influence of tides on the circulation was also investigated using numerical experiments. Besides tides, other types of forcing fields (heat flux, wind stress, evaporation minus precipitation, and freshwater discharge) were also included in the model. Our results indicate that tides play a significant role in shaping the mean circulation of the region. For the summer months, the tidal residual circulation tends to generate a cyclonic gyre in the central Sound. The net transport into the Sound through Hinchinbrook Entrance is reduced. Tides also increase the mixed layer depth in the Sound, especially during the winter months.

  17. Bottom Pressure Tides Along a Line in the Southeast Atlantic Ocean and Comparisons with Satellite Altimetry

    NASA Technical Reports Server (NTRS)

    Ray, Richard D.; Byrne, Deidre A.

    2010-01-01

    Seafloor pressure records, collected at 11 stations aligned along a single ground track of the Topex/Poseidon and Jason satellites, are analyzed for their tidal content. With very low background noise levels and approximately 27 months of high-quality records, tidal constituents can be estimated with unusually high precision. This includes many high-frequency lines up through the seventh-diurnal band. The station deployment provides a unique opportunity to compare with tides estimated from satellite altimetry, point by point along the satellite track, in a region of moderately high mesoscale variability. That variability can significantly corrupt altimeter-based tide estimates, even with 17 years of data. A method to improve the along-track altimeter estimates by correcting the data for nontidal variability is found to yield much better agreement with the bottom-pressure data. The technique should prove useful in certain demanding applications, such as altimetric studies of internal tides.

  18. Estimating the fuel moisture content of indicator sticks from selected weather variables

    Treesearch

    Theodore G. Storey

    1965-01-01

    Equations were developed to predict the fuel moisture content of indicator sticks from the controlling weather variables. Moisture content of ⅛-inch thick basswood slats used in the South and East could be determined with about equal precision by equation in the critical low moisture range or by weighing at fire danger stations. The most useful equation...

  19. Longitudinal Variation of the Lunar Tide in the Equatorial Electrojet

    NASA Astrophysics Data System (ADS)

    Yamazaki, Yosuke; Stolle, Claudia; Matzka, Jürgen; Siddiqui, Tarique A.; Lühr, Hermann; Alken, Patrick

    2017-12-01

    The atmospheric lunar tide is one known source of ionospheric variability. The subject received renewed attention as recent studies found a link between stratospheric sudden warmings and amplified lunar tidal perturbations in the equatorial ionosphere. There is increasing evidence from ground observations that the lunar tidal influence on the ionosphere depends on longitude. We use magnetic field measurements from the CHAMP satellite during July 2000 to September 2010 and from the two Swarm satellites during November 2013 to February 2017 to determine, for the first time, the complete seasonal-longitudinal climatology of the semidiurnal lunar tidal variation in the equatorial electrojet intensity. Significant longitudinal variability is found in the amplitude of the lunar tidal variation, while the longitudinal variability in the phase is small. The amplitude peaks in the Peruvian sector (˜285°E) during the Northern Hemisphere winter and equinoxes, and in the Brazilian sector (˜325°E) during the Northern Hemisphere summer. There are also local amplitude maxima at ˜55°E and ˜120°E. The longitudinal variation is partly due to the modulation of ionospheric conductivities by the inhomogeneous geomagnetic field. Another possible cause of the longitudinal variability is neutral wind forcing by nonmigrating lunar tides. A tidal spectrum analysis of the semidiurnal lunar tidal variation in the equatorial electrojet reveals the dominance of the westward propagating mode with zonal wave number 2 (SW2), with secondary contributions by westward propagating modes with zonal wave numbers 3 (SW3) and 4 (SW4). Eastward propagating waves are largely absent from the tidal spectrum. Further study will be required for the relative importance of ionospheric conductivities and nonmigrating lunar tides.

  20. Mechanisms of maintaining high suspended sediment concentration over tide-dominated offshore shoals in the southern Yellow Sea

    NASA Astrophysics Data System (ADS)

    Xiong, Jilian; Wang, Xiao Hua; Wang, Ya Ping; Chen, Jingdong; Shi, Benwei; Gao, Jianhua; Yang, Yang; Yu, Qian; Li, Mingliang; Yang, Lei; Gong, Xulong

    2017-05-01

    An understanding of the dynamics and behaviors of suspended sediments is vital in analysis of morphological, environmental, and ecological processes occurring in coastal marine environments. To study the mechanisms of maintaining high suspended sediment concentrations (SSCs) on a tide-dominated offshore shoal, we measured water depths, current velocities, SSCs, wave parameters and bottom sediment compositions in the southern Yellow Sea. These data were then used to calculate bottom shear stresses generated by currents (τc), waves (τw), and wave-current interactions (τcw). SSCs time series exhibited strong quarter-diurnal peaks during spring tides, in contrast to the semidiurnal signal during neap tides. A Fourier analysis showed that suspended sediment variations within tidal cycles was mainly controlled by resuspension in most stations. There existed relatively stable background SSCs (maintaining high SSCs among tidal cycles) values at all four stations during both windy (wind speed > 9.0 m/s) and normal weather conditions (wind speed < 3.0 m/s). The background SSCs had strong relationship with spring/neap-averaged τcw, indicating background SSCs were mainly controlled by mean bottom shear stress, with a minimum value of 0.21 N/m2. On account of the strong tidal currents, background SSCs of spring tides were greater than that of neap tides. In addition, on the base of wavelet, statistics analyses and turbulence dissipation parameter, background SSCs during slack tide in the study area may be maintained by intermittent turbulence events induced by a combined tidal current and wave action.

  1. Dynamical significance of tides over the Bay of Bengal

    NASA Astrophysics Data System (ADS)

    Bhagawati, Chirantan; Pandey, Suchita; Dandapat, Sumit; Chakraborty, Arun

    2018-06-01

    Tides play a significant role in the ocean surface circulations and vertical mixing thereby influencing the Sea Surface Temperatures (SST) as well. This, in turn, plays an important role in the global circulation when used as a lower boundary condition in a global atmospheric general circulation model. Therefore in the present study, the dynamics of tides over the Bay of Bengal (BoB) is investigated through numerical simulations using a high resolution (1/12°) Regional Ocean Modeling System (ROMS). Based on statistical analysis it is observed that incorporation of explicit tidal forcing improves the model performance in simulating the basin averaged monthly surface circulation features by 64% compared to the simulation without tides. The model simulates also Mixed Layer Depth (MLD) and SST realistically. The energy exchange between tidal oscillations and eddies leads to redistribution of surface kinetic energy density with a net decrease of 0.012 J m-3 in the western Bay and a net increase of 0.007 J m-3 in the eastern Bay. The tidal forcing also affects the potential energy anomaly and vertical mixing thereby leading to a fall in monthly MLD over the BoB. The mixing due to tides leads to a subsequent reduction in monthly SST and a corresponding reduction in surface heat exchange. These results from the numerical simulation using ROMS reveal that tides have a significant influence over the air-sea heat exchange which is the most important parameter for prediction of Tropical Cyclone frequency and its future variability over the BoB.

  2. Manuel Johnson's Tide Record at St. Helena

    NASA Technical Reports Server (NTRS)

    Cartwright, David E.; Woodworth, Philip L.; Ray, Richard D.

    2017-01-01

    The astronomer Manuel Johnson, a future President of the Royal Astronomical Society, recorded the ocean tides with his own instrument at St. Helena in 1826-1827, while waiting for an observatory to be built. It is an important record in the history of tidal science, as the only previous measurements at St. Helena had been those made by Nevil Maskelyne in 1761, and there were to be no other systematic measurements until the late 20th century. Johnsons tide gauge, of a curious but unique design, recorded efficiently the height of every tidal high and low water for at least 13 months, in spite of requiring frequent re-setting. These heights compare very reasonably with a modern tidal synthesis based on present-day tide gauge measurements from the same site.Johnsons method of timing is unknown, but his calculations of lunar phases suggest that his tidal measurements were recorded in Local Apparent Time. Unfortunately, the recorded times are found to be seriously and variably lagged by many minutes. Johnsons data have never been fully published, but his manuscripts have been safely archived and are available for inspection at Cambridge University. His data have been converted to computerfiles as part of this study for the benefit of future researchers.

  3. Manuel Johnson's tide record at St. Helena

    NASA Astrophysics Data System (ADS)

    Cartwright, David E.; Woodworth, Philip L.; Ray, Richard D.

    2017-03-01

    The astronomer Manuel Johnson, a future President of the Royal Astronomical Society, recorded the ocean tides with his own instrument at St. Helena in 1826-1827, while waiting for an observatory to be built. It is an important record in the history of tidal science, as the only previous measurements at St. Helena had been those made by Nevil Maskelyne in 1761, and there were to be no other systematic measurements until the late 20th century. Johnson's tide gauge, of a curious but unique design, recorded efficiently the height of every tidal high and low water for at least 13 months, in spite of requiring frequent re-setting. These heights compare very reasonably with a modern tidal synthesis based on present-day tide gauge measurements from the same site. Johnson's method of timing is unknown, but his calculations of lunar phases suggest that his tidal measurements were recorded in Local Apparent Time. Unfortunately, the recorded times are found to be seriously and variably lagged by many minutes. Johnson's data have never been fully published, but his manuscripts have been safely archived and are available for inspection at Cambridge University. His data have been converted to computer files as part of this study for the benefit of future researchers.

  4. Influence of solar variability on the occurrence of central European weather types from 1763 to 2009

    NASA Astrophysics Data System (ADS)

    Schwander, Mikhaël; Rohrer, Marco; Brönnimann, Stefan; Malik, Abdul

    2017-09-01

    The impact of solar variability on weather and climate in central Europe is still not well understood. In this paper we use a new time series of daily weather types to analyse the influence of the 11-year solar cycle on the tropospheric weather of central Europe. We employ a novel, daily weather type classification over the period 1763-2009 and investigate the occurrence frequency of weather types under low, moderate, and high solar activity level. Results show a tendency towards fewer days with westerly and west-southwesterly flow over central Europe under low solar activity. In parallel, the occurrence of northerly and easterly types increases. For the 1958-2009 period, a more detailed view can be gained from reanalysis data. Mean sea level pressure composites under low solar activity also show a reduced zonal flow, with an increase of the mean blocking frequency between Iceland and Scandinavia. Weather types and reanalysis data show that the 11-year solar cycle influences the late winter atmospheric circulation over central Europe with colder (warmer) conditions under low (high) solar activity.

  5. Development of Operational Wave-Tide-Storm surges Coupling Prediction System

    NASA Astrophysics Data System (ADS)

    You, S. H.; Park, S. W.; Kim, J. S.; Kim, K. L.

    2009-04-01

    uncoupling and coupling cases for each typhoon. When the typhoon Nabi hit at southern coast of Kyushu, predicted significant wave height reached over 10 m. The difference of significant wave height between wave and wave-tide-storm surges model represents large variation at the southwestern coast of Korea with about 0.5 m. Other typhoon cases also show similar results with typhoon Nabi case. For typhoon Shanshan case the difference of significant wave height reached up to 0.3 m. When the typhoon Nari was affected in the southern coast of Korea, predicted significant wave height was about 5m. The typhoon Nari case also shows the difference of significant wave height similar with other typhoon cases. Using the observation from ocean buoy operated by KMA, we compared wave information simulated by wave and wave-storm surges coupling model. The significant wave height simulated by wave-tide-storm surges model shows the tidal modulation features in the western and southern coast of Korea. And the difference of significant wave height between two models reached up to 0.5 m. The coupling effect also can be identified in the wave direction, wave period and wave length. In addition, wave spectrum is also changeable due to coupling effect of wave-tide-storm surges model. The development, testing and application of a coupling module in which wave-tide-storm surges are incorporated within the frame of KMA Ocean prediction system, has been considered as a step forward in respect of ocean forecasting. In addition, advanced wave prediction model will be applicable to the effect of ocean in the weather forecasting system. The main purpose of this study is to show how the coupling module developed and to report on a series of experiments dealing with the sensitivities and real case prediction of coupling wave-tide-storm surges prediction system.

  6. The pole tide in deep oceans

    NASA Technical Reports Server (NTRS)

    Dickman, S. R.

    1990-01-01

    The fluid-dynamical theory of the pole tide is examined by describing the oceanic response to the Chandler wobble and assessing its implications for mantle anelasticity and low-frequency ocean dynamics. The Laplace tide equations accounting for bottom friction are given, and a spherical harmonic approach is delineated in which the time-independent portion of the tide height is expanded. Pole-tide height and related inertia products are linearly proportional to wobble amplitude, and the final equations are modified to account for mantle elasticity and oceanic loading. Results for pole tide effects are given for various earth models with attention to the role of boundary constraints. A dynamic effect is identified which lengthens the Chandler period by about 1 day more than static lengthening, a contribution that suggests a vigorous low-frequency response. The values derived are shown to agree with previous models that do not incorporate the effects of the pole tide.

  7. Tides and deltaic morphodynamics

    NASA Astrophysics Data System (ADS)

    Plink-Bjorklund, Piret

    2016-04-01

    Tide-dominated and tide-influenced deltas are not widely recognized in the ancient record, despite the numerous modern and Holocene examples, including eight of the twelve modern largest deltas in the world, like the Ganges-Brahmaputra, Amazon, Chang Jiang, and Irrawadi. Furthermore, tide-dominated or tide-influenced deltas are suggested to be more common in inner-shelf or embayment settings rather than close to or at a shelf edge, primarily because wave energy is expected to be higher and tidal energy lower in outer shelf and shelf-edge areas. Thus, most shelf-edge deltas are suggested to be fluvial or wave dominated. However, there are ancient examples of tide-influenced shelf-edge deltas, indicating that the controls on tidal morphodynamics in deltas are not yet well understood. This paper asks the following questions: (1) How do tides influence delta deposition, beyond creating recognizable tidal facies? (2) Does tidal reworking create specific geometries in delta clinoforms? (3) Does tidal reworking change progradation rates of deltas? (4) Is significant tidal reworking of deltas restricted to inner-shelf deltas only? (5) What are the conditions at which deltas may be tidally influenced or tide-dominated in outer-shelf areas or at the shelf edge? (6) What are the main morphodynamic controls on the degree of tidal reworking of deltas? The paper utilizes a dataset of multiple ancient and modern deltas, situated both on the shelf and shelf edge. We show that beyond the commonly recognized shore-perpendicular morphological features and the recognizable tidal facies, the main effects of tidal reworking of deltas are associated with delta clinoform morphology, morphodynamics of delta lobe switching, delta front progradation rates, and the nature of the delta plain. Strong tidal influence is here documented to promote subaqueous, rapid progradation of deltas, by efficiently removing sediment from river mouth and thus reducing mouth bar aggradation and fluvial delta

  8. How climate and weather affect the erosion risk in the northern Gulf of Mexico

    NASA Astrophysics Data System (ADS)

    Wahl, T.; Plant, N. G.

    2015-12-01

    Oceanographic variables such as mean sea level, tides, storm surges, and waves are drivers of erosion, and they act on different time scales ranging from hours (associated with weather) to seasonal and decadal variations and trends (associated with climate). Here we explore how the related sea-state conditions affect the erosion risk in the northern Gulf of Mexico for past and future climate scenarios. From the climate perspective we find that long-term trends in the relevant variables have caused an increase of ~30% in the erosion risk since the 1980s; at least half of this increase was due to changes in the wave climate. In the next decades, sea level rise will likely become the dominating driver and may, in combination with ongoing changes in the wave climate (and depending on the emission scenario), escalate the erosion risk by up to 300% over the next 30 years. We also find significant changes in the seasonal cycles of sea level and significant wave height, which have in combination caused a considerable increase of the erosion risk in summer and decrease in winter (superimposed onto the long-term trends). The influence of weather is assessed with a copula-based multivariate sea storm model in a Monte-Carlo framework; i.e. we simulate hundreds of thousands of artificial but physically consistent sea-state conditions to quantify how different our understanding of the present day erosion risk would be if we had seen more or less extreme combinations of the different sea-state parameters over the last three decades. We find, for example, that total water levels (tide + surge + wave run-up) associated with 100-year return periods may be underestimated by up to 30% and that the average number of impact hours - when total water levels exceeded the height of the dune toe (collision) or dune crest (overwash) - could have been up to 50% higher than what we inferred based on the actually observed oceanographic conditions. Assessing erosion risk in such a probabilistic

  9. Erosion risk in the northern Gulf of Mexico - the effects of climate and weather

    NASA Astrophysics Data System (ADS)

    Wahl, Thomas; Plant, Nathaniel G.; Long, Joseph W.

    2016-04-01

    Oceanographic variables such as mean sea level, tides, storm surges, and waves are drivers of erosion, and they act on different time scales ranging from hours (associated with weather) to seasonal and decadal variations and trends (associated with climate). Here we explore how the related sea-state conditions affect the erosion risk in the northern Gulf of Mexico for past and future climate scenarios. From the climate perspective we find that long-term trends in the relevant variables have caused an increase of ~30% in the erosion risk since the 1980s; at least half of this increase was due to changes in the wave climate. In the next decades, sea level rise will likely become the dominating driver and may, in combination with ongoing changes in the wave climate (and depending on the emission scenario), escalate the erosion risk by up to 300% over the next 30 years. We also find significant changes in the seasonal cycles of sea level and significant wave height, which have in combination caused a considerable increase of the erosion risk in summer and decrease in winter (superimposed onto the long-term trends). The influence of weather is assessed with a copula-based multivariate sea storm model in a Monte-Carlo framework; i.e. we simulate hundreds of thousands of artificial but physically consistent sea-state conditions to quantify how different our understanding of the present day erosion risk would be if we had seen more or less extreme combinations of the different sea-state parameters over the last three decades. We find, for example, that total water levels (tide + surge + wave run-up) associated with 100-year return periods may be underestimated by up to 30% and that the average number of impact hours - when total water levels exceeded the height of the dune toe (collision) or dune crest (overwash) - could have been up to 50% higher than what we inferred based on the actually observed oceanographic conditions. Assessing erosion risk in such a probabilistic

  10. Weather Variability Associated with Aedes (Stegomyia) aegypti (Dengue Vector) Oviposition Dynamics in Northwestern Argentina

    PubMed Central

    Estallo, Elizabet L.; Ludueña-Almeida, Francisco F.; Introini, María V.; Zaidenberg, Mario; Almirón, Walter R.

    2015-01-01

    This study aims to develop a forecasting model by assessing the weather variability associated with seasonal fluctuation of Aedes aegypti oviposition dynamic at a city level in Orán, in northwestern Argentina. Oviposition dynamics were assessed by weekly monitoring of 90 ovitraps in the urban area during 2005-2007. Correlations were performed between the number of eggs collected weekly and weather variables (rainfall, photoperiod, vapor pressure of water, temperature, and relative humidity) with and without time lags (1 to 6 weeks). A stepwise multiple linear regression analysis was performed with the set of meteorological variables from the first year of study with the variables in the time lags that best correlated with the oviposition. Model validation was conducted using the data from the second year of study (October 2006- 2007). Minimum temperature and rainfall were the most important variables. No eggs were found at temperatures below 10°C. The most significant time lags were 3 weeks for minimum temperature and rains, 3 weeks for water vapor pressure, and 6 weeks for maximum temperature. Aedes aegypti could be expected in Orán three weeks after rains with adequate min temperatures. The best-fit forecasting model for the combined meteorological variables explained 70 % of the variance (adj. R2). The correlation between Ae. aegypti oviposition observed and estimated by the forecasting model resulted in rs = 0.80 (P < 0.05). The forecasting model developed would allow prediction of increases and decreases in the Ae. aegypti oviposition activity based on meteorological data for Orán city and, according to the meteorological variables, vector activity can be predicted three or four weeks in advance. PMID:25993415

  11. Variability of High-Resolution Sea Surface Heights on a Broad, Shallow Continental Shelf

    NASA Astrophysics Data System (ADS)

    Crout, R. L.; Rice, A. E.

    2017-12-01

    Recent satellite altimeter technologies and processing methodologies are allowing investigation of the dynamics of the continental shelf as never before. The region seaward of 20 km from the coast is a region where winds, tides, currents, river discharge, and bathymetry interact. All of these are important parameters to understand when applying coastal altimetry to coastal sea level monitoring. Processing of 8 years (July 2008 to July 2016) of Jason-2 altimeter 20 Hz data from the L2 AVISO-PISTACH experimental products yields nearly 300 crossings of the broad continental shelf to the southeast of Delaware Bay from Cape May, NJ. Removal of a mean surface yields individual crossings that, plotted together, form an envelope that shows high water level variability near the coast. Water level changes near the coast begin at a hinge point that occurs approximately 50 km from shore in less than 30 meters of water. Comparison of individual Jason-2 passes with regional weather patterns, cold front passages, local winds, tides, surface currents, river discharge, and regional oceanography provides information regarding the forcing factors for these regional water levels. The water levels farther than 20 km from shore show similar patterns to the low pass filtered tide data at Cape May, NJ and respond primarily to regional forcing.

  12. Reconstruction of Historical Weather by Assimilating Old Weather Diary Data

    NASA Astrophysics Data System (ADS)

    Neluwala, P.; Yoshimura, K.; Toride, K.; Hirano, J.; Ichino, M.; Okazaki, A.

    2017-12-01

    Climate can control not only human life style but also other living beings. It is important to investigate historical climate to understand the current and future climates. Information about daily weather can give a better understanding of past life on earth. Long-term weather influences crop calendar as well as the development of civilizations. Unfortunately, existing reconstructed daily weather data are limited to 1850s due to the availability of instrumental data. The climate data prior to that are derived from proxy materials (e.g., tree-ring width, ice core isotopes, etc.) which are either in annual or decadal scale. However, there are many historical documents which contain information about weather such as personal diaries. In Japan, around 20 diaries in average during the 16th - 19th centuries have been collected and converted into a digitized form. As such, diary data exist in many other countries. This study aims to reconstruct historical daily weather during the 18th and 19th centuries using personal daily diaries which have analogue weather descriptions such as `cloudy' or `sunny'. A recent study has shown the possibility of assimilating coarse weather data using idealized experiments. We further extend this study by assimilating modern weather descriptions similar to diary data in recent periods. The Global Spectral model (GSM) of National Centers for Environmental Prediction (NCEP) is used to reconstruct weather with the Local Ensemble Kalman filter (LETKF). Descriptive data are first converted to model variables such as total cloud cover (TCC), solar radiation and precipitation using empirical relationships. Those variables are then assimilated on a daily basis after adding random errors to consider the uncertainty of actual diary data. The assimilation of downward short wave solar radiation using weather descriptions improves RMSE from 64.3 w/m2 to 33.0 w/m2 and correlation coefficient (R) from 0.5 to 0.8 compared with the case without any

  13. Reprint of Mechanisms of maintaining high suspended sediment concentration over tide-dominated offshore shoals in the southern Yellow Sea

    NASA Astrophysics Data System (ADS)

    Xiong, Jilian; Wang, Xiao Hua; Wang, Ya Ping; Chen, Jingdong; Shi, Benwei; Gao, Jianhua; Yang, Yang; Yu, Qian; Li, Mingliang; Yang, Lei; Gong, Xulong

    2018-06-01

    An understanding of the dynamics and behaviors of suspended sediments is vital in analysis of morphological, environmental, and ecological processes occurring in coastal marine environments. To study the mechanisms of maintaining high suspended sediment concentrations (SSCs) on a tide-dominated offshore shoal, we measured water depths, current velocities, SSCs, wave parameters and bottom sediment compositions in the southern Yellow Sea. These data were then used to calculate bottom shear stresses generated by currents (τc), waves (τw), and wave-current interactions (τcw). SSCs time series exhibited strong quarter-diurnal peaks during spring tides, in contrast to the semidiurnal signal during neap tides. A Fourier analysis showed that suspended sediment variations within tidal cycles was mainly controlled by resuspension in most stations. There existed relatively stable background SSCs (maintaining high SSCs among tidal cycles) values at all four stations during both windy (wind speed > 9.0 m/s) and normal weather conditions (wind speed < 3.0 m/s). The background SSCs had strong relationship with spring/neap-averaged τcw, indicating background SSCs were mainly controlled by mean bottom shear stress, with a minimum value of 0.21 N/m2. On account of the strong tidal currents, background SSCs of spring tides were greater than that of neap tides. In addition, on the base of wavelet, statistics analyses and turbulence dissipation parameter, background SSCs during slack tide in the study area may be maintained by intermittent turbulence events induced by a combined tidal current and wave action.

  14. Representation of solar tides in the stratosphere and lower mesosphere in state-of-the-art reanalyses and in satellite observations

    NASA Astrophysics Data System (ADS)

    Sakazaki, Takatoshi; Fujiwara, Masatomo; Shiotani, Masato

    2018-02-01

    Atmospheric solar tides in the stratosphere and the lower mesosphere are investigated using temperature data from five state-of-the-art reanalysis data sets (MERRA-2, MERRA, JRA-55, ERA-Interim, and CFSR) as well as TIMED SABER and Aura MLS satellite measurements. The main focus is on the period 2006-2012 during which the satellite observations are available for direct comparison with the reanalyses. Diurnal migrating tides, semidiurnal migrating tides, and nonmigrating tides are diagnosed. Overall the reanalyses agree reasonably well with each other and with the satellite observations for both migrating and nonmigrating components, including their vertical structure and the seasonality. However, the agreement among reanalyses is more pronounced in the lower stratosphere and relatively weaker in the upper stratosphere and mesosphere. A systematic difference between SABER and the reanalyses is found for diurnal migrating tides in the upper stratosphere and the lower mesosphere; specifically, the amplitude of trapped modes in reanalyses is significantly smaller than that in SABER, although such difference is less clear between MLS and the reanalyses. The interannual variability and the possibility of long-term changes in migrating tides are also examined using the reanalyses during 1980-2012. All the reanalyses agree in exhibiting a clear quasi-biennial oscillation (QBO) in the tides, but the most significant indications of long-term changes in the tides represented in the reanalyses are most plausibly explained by the evolution of the satellite observing systems during this period. The tides are also compared in the full reanalyses produced by the Japan Meteorological Agency (i.e., JRA-55) and in two parallel data sets from this agency: one (JRA-55C) that repeats the reanalysis procedure but without any satellite data assimilated and one (JRA-55AMIP) that is a free-running integration of the model constrained only by observed sea surface temperatures. Many aspects

  15. A method to assess the inter-annual weather-dependent variability in air pollution concentration and deposition based on weather typing

    NASA Astrophysics Data System (ADS)

    Pleijel, Håkan; Grundström, Maria; Karlsson, Gunilla Pihl; Karlsson, Per Erik; Chen, Deliang

    2016-02-01

    Annual anomalies in air pollutant concentrations, and deposition (bulk and throughfall) of sulphate, nitrate and ammonium, in the Gothenburg region, south-west Sweden, were correlated with optimized linear combinations of the yearly frequency of Lamb Weather Types (LWTs) to determine the extent to which the year-to-year variation in pollution exposure can be partly explained by weather related variability. Air concentrations of urban NO2, CO, PM10, as well as O3 at both an urban and a rural monitoring site, and the deposition of sulphate, nitrate and ammonium for the period 1997-2010 were included in the analysis. Linear detrending of the time series was performed to estimate trend-independent anomalies. These estimated anomalies were subtracted from observed annual values. Then the statistical significance of temporal trends with and without LWT adjustment was tested. For the pollutants studied, the annual anomaly was well correlated with the annual LWT combination (R2 in the range 0.52-0.90). Some negative (annual average [NO2], ammonia bulk deposition) or positive (average urban [O3]) temporal trends became statistically significant (p < 0.05) when the LWT adjustment was applied. In all the cases but one (NH4 throughfall, for which no temporal trend existed) the significance of temporal trends became stronger with LWT adjustment. For nitrate and ammonium, the LWT based adjustment explained a larger fraction of the inter-annual variation for bulk deposition than for throughfall. This is probably linked to the longer time scale of canopy related dry deposition processes influencing throughfall being explained to a lesser extent by LWTs than the meteorological factors controlling bulk deposition. The proposed novel methodology can be used by authorities responsible for air pollution management, and by researchers studying temporal trends in pollution, to evaluate e.g. the relative importance of changes in emissions and weather variability in annual air pollution

  16. Nordic Sea Level - Analysis of PSMSL RLR Tide Gauge data

    NASA Astrophysics Data System (ADS)

    Knudsen, Per; Andersen, Ole

    2015-04-01

    Tide gauge data from the Nordic region covering a period of time from 1920 to 2000 are evaluated. 63 stations having RLR data for at least 40 years have been used. Each tide gauge data record was averaged to annual averages after the monthly average seasonal anomalies were removed. Some stations lack data, especially before around 1950. Hence, to compute representative sea level trends for the 1920-2000 period a procedure for filling in estimated sea level values in the voids, is needed. To fill in voids in the tide gauge data records a reconstruction method was applied that utilizes EOF.s in an iterative manner. Subsequently the trends were computed. The estimated trends range from about -8 mm/year to 2 mm/year reflecting both post-glacial uplift and sea level rise. An evaluation of the first EOFs show that the first EOF clearly describes the trends in the time series. EOF #2 and #3 describe differences in the inter-annual sea level variability with-in the Baltic Sea and differences between the Baltic and the North Atlantic / Norwegian seas, respectively.

  17. Seasonal variability of atmospheric surface layer characteristics and weather pattern in Qatar

    NASA Astrophysics Data System (ADS)

    Samanta, Dhrubajyoti; Cheng, Way Lee; Sadr, Reza

    2016-11-01

    Qatar's economy is based on oil and gas industry, which are mostly located in coastal regions. Therefore, better understanding of coastal weather, characteristics of surface layer and turbulence exchange processes is much needed. However, the turbulent atmospheric layer study in this region is severely limited. To support the broader aim and study long term precise wind information, a micro-meteorological field campaign has been carried out in a coastal location of north Qatar. The site is based on a 9 m tower, installed at Al Ghariya in the northern coast of Qatar, equipped with three sonic anemometers, temperature-humidity sensor, radiometer and a weather station. This study shows results based on the period August 2015 to July 2016. Various surface layer characteristics and modellings coefficients based on Monin Obukhov similarity theory is studied for the year and seasonal change is noted. Along with the seasonal variabilities of different weather parameters also observed. We hope this long term field observational study will be very much helpful for research community especially for modelers. In addition, two beach and shoreline monitoring cameras installed at the site could give first time information on waves and shoreline changes, and wind-wave interaction in Qatar. An Preliminary Analysis of Wind-Wave Interaction in Qatar in the Context of Changing Climate.

  18. Apparent Relations Between Solar Activity and Solar Tides Caused by the Planets

    NASA Technical Reports Server (NTRS)

    Hung, Ching-Cheh

    2007-01-01

    A solar storm is a storm of ions and electrons from the Sun. Large solar storms are usually preceded by solar flares, phenomena that can be characterized quantitatively from Earth. Twenty-five of the thirty-eight largest known solar flares were observed to start when one or more tide-producing planets (Mercury, Venus, Earth, and Jupiter) were either nearly above the event positions (less than 10 deg. longitude) or at the opposing side of the Sun. The probability for this to happen at random is 0.039 percent. This supports the hypothesis that the force or momentum balance (between the solar atmospheric pressure, the gravity field, and magnetic field) on plasma in the looping magnetic field lines in solar corona could be disturbed by tides, resulting in magnetic field reconnection, solar flares, and solar storms. Separately, from the daily position data of Venus, Earth, and Jupiter, an 11-year planet alignment cycle is observed to approximately match the sunspot cycle. This observation supports the hypothesis that the resonance and beat between the solar tide cycle and nontidal solar activity cycle influences the sunspot cycle and its varying magnitudes. The above relations between the unpredictable solar flares and the predictable solar tidal effects could be used and further developed to forecast the dangerous space weather and therefore reduce its destructive power against the humans in space and satellites controlling mobile phones and global positioning satellite (GPS) systems.

  19. Galalctic Tides & the Sinusoidal Potential

    NASA Astrophysics Data System (ADS)

    Bartlett, David F.

    2011-05-01

    The sinusoidal potential is a nonNewtonian alternative to dark matter. Instead of φ = -GM/r we write φ = -(GM/r) cos kor, where ko= 2π/ λo and λo = Ro/20= 400 pc. Evidence for this choice for the "wavelength” λo has been given in one article and many previous meetings of the AAS & DDA. The solar system and nearby stars are trapped in a local groove of width Δr < 400 pc. The rapid alternation of attraction and repulsion within the groove gives very strong Galactic radial tides. The epicyclic period is only 7 Myr . The Keplerian period for comets in the middle of the Oort cloud is also 7 Myr. The 1:1 resonance between material in the groove and the cloud provides a new mechanism for filling the Oort cloud. The Oort cloud is emptied by the same strong radial tides. Evidence is found in the 499 comets with calculated 1/aoriginal in the latest Catalogue of Cometary Orbits (Marsden & Williams 2008). . I separate the comets into 12 classes on the basis of Quality (4 types) and semi-major axis aoriginal . For 10 of the 12 classes radial tides dominate Z-tides. The classic Oort cloud comets (1851-1996) have a particularly strong modulation with galactic longitude. This modulation is exactly in those directions where a radial tide would be important. The equally numerous recent Oort comets (1996-2008) show a different evidence for strong radial tides. The recent comets generally have much larger perihelion distances q than the classic ones. Here the evidence is that a radial tide is removing angular momentum from the orbit and thus bringing the perihelion closer to the earth and to observers.

  20. Modeling the influence of preferential flow on the spatial variability and time-dependence of mineral weathering rates

    DOE PAGES

    Pandey, Sachin; Rajaram, Harihar

    2016-12-05

    Inferences of weathering rates from laboratory and field observations suggest significant scale and time-dependence. Preferential flow induced by heterogeneity (manifest as permeability variations or discrete fractures) has been suggested as one potential mechanism causing scale/time-dependence. In this paper, we present a quantitative evaluation of the influence of preferential flow on weathering rates using reactive transport modeling. Simulations were performed in discrete fracture networks (DFNs) and correlated random permeability fields (CRPFs), and compared to simulations in homogeneous permeability fields. The simulations reveal spatial variability in the weathering rate, multidimensional distribution of reactions zones, and the formation of rough weathering interfaces andmore » corestones due to preferential flow. In the homogeneous fields and CRPFs, the domain-averaged weathering rate is initially constant as long as the weathering front is contained within the domain, reflecting equilibrium-controlled behavior. The behavior in the CRPFs was influenced by macrodispersion, with more spread-out weathering profiles, an earlier departure from the initial constant rate and longer persistence of weathering. DFN simulations exhibited a sustained time-dependence resulting from the formation of diffusion-controlled weathering fronts in matrix blocks, which is consistent with the shrinking core mechanism. A significant decrease in the domain-averaged weathering rate is evident despite high remaining mineral volume fractions, but the decline does not follow a math formula dependence, characteristic of diffusion, due to network scale effects and advection-controlled behavior near the inflow boundary. Finally, the DFN simulations also reveal relatively constant horizontally averaged weathering rates over a significant depth range, challenging the very notion of a weathering front.« less

  1. Modeling the influence of preferential flow on the spatial variability and time-dependence of mineral weathering rates

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Pandey, Sachin; Rajaram, Harihar

    Inferences of weathering rates from laboratory and field observations suggest significant scale and time-dependence. Preferential flow induced by heterogeneity (manifest as permeability variations or discrete fractures) has been suggested as one potential mechanism causing scale/time-dependence. In this paper, we present a quantitative evaluation of the influence of preferential flow on weathering rates using reactive transport modeling. Simulations were performed in discrete fracture networks (DFNs) and correlated random permeability fields (CRPFs), and compared to simulations in homogeneous permeability fields. The simulations reveal spatial variability in the weathering rate, multidimensional distribution of reactions zones, and the formation of rough weathering interfaces andmore » corestones due to preferential flow. In the homogeneous fields and CRPFs, the domain-averaged weathering rate is initially constant as long as the weathering front is contained within the domain, reflecting equilibrium-controlled behavior. The behavior in the CRPFs was influenced by macrodispersion, with more spread-out weathering profiles, an earlier departure from the initial constant rate and longer persistence of weathering. DFN simulations exhibited a sustained time-dependence resulting from the formation of diffusion-controlled weathering fronts in matrix blocks, which is consistent with the shrinking core mechanism. A significant decrease in the domain-averaged weathering rate is evident despite high remaining mineral volume fractions, but the decline does not follow a math formula dependence, characteristic of diffusion, due to network scale effects and advection-controlled behavior near the inflow boundary. Finally, the DFN simulations also reveal relatively constant horizontally averaged weathering rates over a significant depth range, challenging the very notion of a weathering front.« less

  2. Effect of Southern Hemisphere Sudden Stratospheric Warmings on Antarctica Mesospheric Tides: First Observational Study

    NASA Astrophysics Data System (ADS)

    Eswaraiah, S.; Kim, Yong Ha; Lee, Jaewook; Ratnam, M. Vankat; Rao, S. V. B.

    2018-03-01

    We analyzed the structure and variability of observed winds and tides in the Antarctica mesosphere and lower thermosphere (MLT) during the 2002 major sudden stratospheric warming (SSW) and the 2010 minor SSWs. We noted the effect of SSW on the variability of MLT tides for the first time in the Southern Hemisphere, although it has been well recognized in the Northern Hemisphere. We utilized the winds measured by Rothera (68°S, 68°W) medium frequency radar and King Sejong Station (62.22°S, 58.78°W) meteor radar for estimating the tidal components (diurnal, semi-diurnal, and ter-diurnal) in the MLT region. The unusual behavior of diurnal tide (DT) and semidiurnal tide (SDT) was observed in 2002. Zonal SDT amplitudes were enhanced up to 27 m/s after 18 days from the associated SSW day. However, the meridional tidal amplitudes of both DT and SDT suddenly decreased during the peak SSW, and SDT amplitudes slightly increased to 18 m/s afterward. In the normal years, SDT amplitude stays below 15 m/s. During the 2010 SSW, SDT zonal amplitudes increased up to 40 m/s and 50 m/s at altitudes of 80 km and 90 km, respectively, 30 days after the associated SSW. Similar but weaker effect is noticed in the meridional components. The ter-diurnal tide does not show any significant variation during the SSW. The two SSWs offered a challenging issue to answer: why tidal amplitudes are enhanced with a delay after the SSW. The reasons for the delay are discussed in accordance with theoretical predictions.

  3. Mapping hurricane rita inland storm tide

    USGS Publications Warehouse

    Berenbrock, C.; Mason, R.R.; Blanchard, S.F.

    2009-01-01

    Flood-inundation data are most useful for decision makers when presented in the context of maps of affected communities and (or) areas. But because the data are scarce and rarely cover the full extent of the flooding, interpolation and extrapolation of the information are needed. Many geographic information systems provide various interpolation tools, but these tools often ignore the effects of the topographic and hydraulic features that influence flooding. A barrier mapping method was developed to improve maps of storm tide produced by Hurricane Rita. Maps were developed for the maximum storm tide and at 3-h intervals from midnight (00:00 hours) through noon (12:00 hours) on 24 September 2005. The improved maps depict storm-tide elevations and the extent of flooding. The extent of storm-tide inundation from the improved maximum storm-tide map was compared with the extent of flood inundation from a map prepared by the Federal Emergency Management Agency (FEMA). The boundaries from these two maps generally compared quite well especially along the Calcasieu River. Also a cross-section profile that parallels the Louisiana coast was developed from the maximum storm-tide map and included FEMA high-water marks. ?? 2009 Blackwell Publishing Ltd.

  4. Mapping Hurricane Rita inland storm tide

    USGS Publications Warehouse

    Berenbrock, Charles; Mason, Jr., Robert R.; Blanchard, Stephen F.; Simonovic, Slobodan P.

    2009-01-01

    Flood-inundation data are most useful for decision makers when presented in the context of maps of effected communities and (or) areas. But because the data are scarce and rarely cover the full extent of the flooding, interpolation and extrapolation of the information are needed. Many geographic information systems (GIS) provide various interpolation tools, but these tools often ignore the effects of the topographic and hydraulic features that influence flooding. A barrier mapping method was developed to improve maps of storm tide produced by Hurricane Rita. Maps were developed for the maximum storm tide and at 3-hour intervals from midnight (0000 hour) through noon (1200 hour) on September 24, 2005. The improved maps depict storm-tide elevations and the extent of flooding. The extent of storm-tide inundation from the improved maximum storm-tide map was compared to the extent of flood-inundation from a map prepared by the Federal Emergency Management Agency (FEMA). The boundaries from these two maps generally compared quite well especially along the Calcasieu River. Also a cross-section profile that parallels the Louisiana coast was developed from the maximum storm-tide map and included FEMA high-water marks.

  5. Ocean tides from Seasat-A

    NASA Technical Reports Server (NTRS)

    Hendershott, M. C.; Munk, W. H.; Zetler, B. D.

    1974-01-01

    Two procedures for the evaluation of global tides from SEASAT-A altimetry data are elaborated: an empirical method leading to the response functions for a grid of about 500 points from which the tide can be predicted for any point in the oceans, and a dynamic method which consists of iteratively modifying the parameters in a numerical solution to Laplace tide equations. It is assumed that the shape of the received altimeter signal can be interpreted for sea state and that orbit calculations are available so that absolute sea levels can be obtained.

  6. King Tides and Climate Change

    EPA Pesticide Factsheets

    The highest predicted high tide of the year at a coastal location can bring unusually high water levels and can cause flooding. Learn about these tides including what they are, when they occur, and what they can mean for the future.

  7. Assessing change of environmental dynamics by legislation in Japan, using red tide occurrence in Ise Bay as an indicator.

    PubMed

    Suzuki, Chika

    2016-01-30

    Tokyo Bay, Ise Bay, and the Seto Inland Sea are the total pollutant load control target areas in Japan. A significant correlation between the incidence of red tides and water quality has been observed in the Seto Inland Sea (Honjo, 1991). However, while red tides also occur in Ise Bay and Tokyo Bay, similar correlations have not been observed. Hence, it is necessary to understand what factors cause red tides to effectively manage these semi-closed systems. This study aims to investigate the relationship between the dynamics of the Red Tide Index and nitrogen regulation as well as phosphorus regulation, even in Ise Bay where, unlike Tokyo Bay, there are few observation items, by selecting a suitable objective variable. The introduction of a new technique that uses the Red Tide Index has revealed a possibility that the total pollution load control has influenced the dynamics of red tide blooms in Ise Bay. Copyright © 2015 Elsevier Ltd. All rights reserved.

  8. Future Change to Tide-Influenced Deltas

    NASA Astrophysics Data System (ADS)

    Nienhuis, Jaap H.; Hoitink, A. J. F. (Ton); Törnqvist, Torbjörn E.

    2018-04-01

    Tides tend to widen deltaic channels and shape delta morphology. Here we present a predictive approach to assess a priori the effect of fluvial discharge and tides on deltaic channels. We show that downstream channel widening can be quantified by the ratio of the tide-driven discharge and the fluvial discharge, along with a second metric representing flow velocities. A test of our new theory on a selection of 72 deltas globally shows good correspondence to a wide range of environments, including wave-dominated deltas, river-dominated deltas, and alluvial estuaries. By quantitatively relating tides and fluvial discharge to delta morphology, we offer a first-order prediction of deltaic change that may be expected from altered delta hydrology. For example, we expect that reduced fluvial discharge in response to dam construction will lead to increased tidal intrusion followed by enhanced tide-driven sediment import into deltas, with implications for navigation and other human needs.

  9. The Art of Red Tide Science

    PubMed Central

    Hall, Emily R.; Nierenberg, Kate; Boyes, Anamari J.; Heil, Cynthia A.; Flewelling, Leanne J.; Kirkpatrick, Barbara

    2012-01-01

    Over the years, numerous outreach strategies by the science community, such as FAQ cards and website information, have been used to explain blooms of the toxic dinoflagellate, Karenia brevis that occur annually off the west coast of Florida to the impacted communities. Many state and federal agencies have turned to funded research groups for assistance in the development and testing of environmental outreach products. In the case of Florida red tide, the Fish and Wildlife Research Institute/Mote Marine Laboratory (MML) Cooperative Red Tide Agreement allowed MML to initiate a project aimed at developing innovative outreach products about Florida red tide. This project, which we coined “The Art of Red Tide Science,” consisted of a team effort between scientists from MML and students from Ringling College of Art and Design. This successful outreach project focused on Florida red tide can be used as a model to develop similar outreach projects for equally complex ecological issues. PMID:22712002

  10. The Art of Red Tide Science.

    PubMed

    Hall, Emily R; Nierenberg, Kate; Boyes, Anamari J; Heil, Cynthia A; Flewelling, Leanne J; Kirkpatrick, Barbara

    2012-05-01

    Over the years, numerous outreach strategies by the science community, such as FAQ cards and website information, have been used to explain blooms of the toxic dinoflagellate, Karenia brevis that occur annually off the west coast of Florida to the impacted communities. Many state and federal agencies have turned to funded research groups for assistance in the development and testing of environmental outreach products. In the case of Florida red tide, the Fish and Wildlife Research Institute/Mote Marine Laboratory (MML) Cooperative Red Tide Agreement allowed MML to initiate a project aimed at developing innovative outreach products about Florida red tide. This project, which we coined "The Art of Red Tide Science," consisted of a team effort between scientists from MML and students from Ringling College of Art and Design. This successful outreach project focused on Florida red tide can be used as a model to develop similar outreach projects for equally complex ecological issues.

  11. Energetics of global ocean tides from Geosat altimetry

    NASA Technical Reports Server (NTRS)

    Cartwright, David E.; Ray, Richard D.

    1991-01-01

    The present paper focuses on resonance and energetics of the daily tides, especially in the southern ocean, the distribution of gravitational power input of daily and half-daily tides, and comparison with other estimates of global dissipation rates. The present global tidal maps, derived from Geosat altimetry, compare favorably with ground truth data at about the same rms level as the models of Schwiderski (1983), and are slightly better in lunar than in solar tides. Diurnal admittances clearly show Kelvin wave structure in the southern ocean and confirm the resonant mode of Platzman (1984) at 28.5 + or - 0.1 hr with an apparent Q of about 4. Driving energy is found to enter dominantly in the North Pacific for the daily tides and is strongly peaked in the tropical oceans for the half-daily tides. Global rates of working on all major tide constituents except S2 agree well with independent results from analyses of gravity through satellite tracking. Comparison at S2 is improved by allowing for the air tide in gravitational results but suggests deficiencies in all solar tide models.

  12. Deep sea tides determination from GEOS-3

    NASA Technical Reports Server (NTRS)

    Maul, G. A.; Yanaway, A.

    1978-01-01

    GEOS 3 altimeter data in a 5 degree X 5 degree square centered at 30 deg N, 70 deg W were analyzed to evaluate deep sea tide determination from a spacecraft. The signal to noise ratio of known tidal variability to altimeter measurement of sea level above the ellipsoid was 0.1. A sample was obtained in a 5 deg x 5 deg area approximately once every four days. The randomly spaced time series was analyzed using two independent least squares techniques.

  13. Direct and Indirect Effects of Tides on Ecosystem-Scale CO2 Exchange in a Brackish Tidal Marsh in Northern California

    NASA Astrophysics Data System (ADS)

    Knox, S. H.; Windham-Myers, L.; Anderson, F.; Sturtevant, C.; Bergamaschi, B.

    2018-03-01

    We investigated the direct and indirect influence of tides on net ecosystem exchange (NEE) of carbon dioxide (CO2) in a temperate brackish tidal marsh. NEE displayed a tidally driven pattern with obvious characteristics at the multiday scale, with greater net CO2 uptake during spring tides than neap tides. Based on the relative mutual information between NEE and biophysical variables, this was driven by a combination of higher water table depth (WTD), cooler air temperature, and lower vapor pressure deficit (VPD) during spring tides relative to neap tides, as the fortnightly tidal cycle not only influenced water levels but also strongly modulated water and air temperature and VPD. Tides also influenced NEE at shorter timescales, with a reduction in nighttime fluxes during growing season spring tides when the higher of the two semidiurnal tides caused inundation at the site. WTD significantly influenced ecosystem respiration (Reco), with lower Reco during spring tides than neap tides. While WTD did not appear to affect ecosystem photosynthesis (gross ecosystem production, GPP) directly, the impact of tides on temperature and VPD influenced GPP, with higher daily light-use efficiency and photosynthetic activity during spring tides than neap tides when temperature and VPD were lower. The strong direct and indirect influence of tides on NEE across the diel and multiday timescales has important implications for modeling NEE in tidal wetlands and can help inform the timing and frequency of chamber measurements as annual or seasonal net CO2 uptake may be underestimated if measurements are only taken during nonflooded periods.

  14. Seasonal modulation of M2 tide in the Northern Bay of Bengal

    NASA Astrophysics Data System (ADS)

    Tazkia, A. R.; Krien, Y.; Durand, F.; Testut, L.; Islam, AKM S.; Papa, F.; Bertin, X.

    2017-04-01

    The Northern Bay of Bengal (BoB) with its adjoining Ganges-Brahmaputra-Meghna delta (GBM) forms the largest deltaic region in the world. It is surrounded by a wide area of low-lying land (less than a few meters above mean sea level), very densely populated. It is home to a strong variability of sea level, across all timescales, with ample tides and frequent storm surges. It is also subject to extended river flooding during the monsoon season, with frequent overflows of two of the world's largest rivers (Brahmaputra and Ganges). There is thus a need to understand and predict the various mechanisms responsible for coastal and estuarine water level variability in this area. In this study, we address one of the least understood facets of this variability: the low-frequency modulation of tides. We focus on the seasonal changes of amplitude of the semi-diurnal lunar tide, M2. It is found that M2 amplitude shows marked changes between winter and summer seasons (of order 10 cm), incommensurate with most of the world's coastal ocean. We observe contrasted patterns from the open areas of the coastal ocean to the inner part of the GBM estuary. In the coastal ocean and over most of the GBM delta, M2 amplitude is stronger during summer and decreases until winter. Conversely, in the far northern part of GBM estuary, M2 amplitude is stronger during winter and weaker during summer. We make use of a hydrodynamic barotropic tidal model to decipher the processes responsible for this evolution. It is found that throughout the coastal ocean and over most of the GBM delta, this evolution is driven by frictional effects, with a seasonal modulation of bottom dissipation of tidal energy. Our simple barotropic model, however, does not capture the observed range of seasonal modulation of tides in the GBM estuary and at its mouth. Our study advocates for a careful consideration of these processes for a proper representation of the tidal dynamics as well as of the flooding hazard in the Bengal

  15. Florida Red Tide Perception: Residents versus Tourists

    PubMed Central

    Nierenberg, Kate; Byrne, Margaret; Fleming, Lora E.; Stephan, Wendy; Reich, Andrew; Backer, Lorraine C.; Tanga, Elvira; Dalpra, Dana R.; Kirkpatrick, Barbara

    2010-01-01

    The west coast of Florida has annual blooms of the toxin-producing dinoflagellate, Karenia brevis with Sarasota, FL considered the epicenter for these blooms. Numerous outreach materials, including Frequently Asked Question (FAQ) cards, exhibits for local museums and aquaria, public beach signs, and numerous websites have been developed to disseminate information to the public about this natural hazard. In addition, during intense onshore blooms, a great deal of media attention, primarily via newspaper (print and web) and television, is focused on red tide. However to date, the only measure of effectiveness of these outreach methods has been counts of the number of people exposed to the information, e.g., visits to a website or number of FAQ cards distributed. No formal assessment has been conducted to determine if these materials meet their goal of informing the public about Florida red tide. Also, although local residents have the opinion that they are very knowledgeable about Florida red tide, this has not been verified empirically. This study addressed these issues by creating and administering an evaluation tool for the assessment of public knowledge about Florida red tide. A focus group of Florida red tide outreach developers assisted in the creation of the evaluation tool. The location of the evaluation was the west coast of Florida, in Sarasota County. The objective was to assess the knowledge of the general public about Florida red tide. This assessment identified gaps in public knowledge regarding Florida red tides and also identified what information sources people want to use to obtain information on Florida red tide. The results from this study can be used to develop more effective outreach materials on Florida red tide. PMID:20824108

  16. Florida Red Tide Perception: Residents versus Tourists.

    PubMed

    Nierenberg, Kate; Byrne, Margaret; Fleming, Lora E; Stephan, Wendy; Reich, Andrew; Backer, Lorraine C; Tanga, Elvira; Dalpra, Dana R; Kirkpatrick, Barbara

    2010-09-01

    The west coast of Florida has annual blooms of the toxin-producing dinoflagellate, Karenia brevis with Sarasota, FL considered the epicenter for these blooms. Numerous outreach materials, including Frequently Asked Question (FAQ) cards, exhibits for local museums and aquaria, public beach signs, and numerous websites have been developed to disseminate information to the public about this natural hazard. In addition, during intense onshore blooms, a great deal of media attention, primarily via newspaper (print and web) and television, is focused on red tide. However to date, the only measure of effectiveness of these outreach methods has been counts of the number of people exposed to the information, e.g., visits to a website or number of FAQ cards distributed. No formal assessment has been conducted to determine if these materials meet their goal of informing the public about Florida red tide. Also, although local residents have the opinion that they are very knowledgeable about Florida red tide, this has not been verified empirically. This study addressed these issues by creating and administering an evaluation tool for the assessment of public knowledge about Florida red tide. A focus group of Florida red tide outreach developers assisted in the creation of the evaluation tool. The location of the evaluation was the west coast of Florida, in Sarasota County. The objective was to assess the knowledge of the general public about Florida red tide. This assessment identified gaps in public knowledge regarding Florida red tides and also identified what information sources people want to use to obtain information on Florida red tide. The results from this study can be used to develop more effective outreach materials on Florida red tide.

  17. Monitoring storm tide and flooding from Hurricane Isaac along the Gulf Coast of the United States, August 2012

    USGS Publications Warehouse

    McCallum, Brian E.; McGee, Benton D.; Kimbrow, Dustin R.; Runner, Michael S.; Painter, Jaime A.; Frantz, Eric R.; Gotvald, Anthony J.

    2012-01-01

    The U.S. Geological Survey (USGS) deployed a temporary monitoring network of water-level and barometric pressure sensors at 127 locations along the gulf coast from Alabama to Louisiana to record the timing, areal extent, and magnitude of hurricane storm tide and coastal flooding generated by Hurricane Isaac. This deployment was undertaken as part of a coordinated federal emergency response as outlined by the Stafford Act under a directed mission assignment by the Federal Emergency Management Agency. Storm tide, as defined by National Oceanic and Atmospheric Administration (NOAA; National Oceanic and Atmospheric Administration, 2008), is the water-level rise generated by a combination of storm surge and astronomical tide during a coastal storm. Hurricane Isaac initially made landfall on the coast of Louisiana in Plaquemines Parish on August 28, 2012, as a Category 1 hurricane on the Saffir–Simpson Hurricane Wind Scale (National Weather Service, 1974) and then stalled over southern Louisiana for several days, causing prolonged storm-tide impacts. A total of 188 water-level and wave-height sensors were deployed at 127 locations during August 27–28 prior to landfall. More than 90 percent of the sensors and all high-water marks (HWMs) were recovered and surveyed to North American Vertical Datum of 1988 (NAVD 88) within 7 days of the Isaac landfall. Only a handful of sensors in the Plaquemines Parish area of Louisiana could not be retrieved until weeks later due to prolonged flooding in the area. Data collected from this event can be used to evaluate the performance of storm-tide models for maximum and incremental water level and flood extent and the site-specific effects of storm tide on natural and anthropogenic features of the environment.

  18. Excitation mechanism of non-migrating tides

    NASA Astrophysics Data System (ADS)

    Miyoshi, Yasunobu; Pancheva, Dora; Mukhtarov, Plamen; Jin, Hidekatsu; Fujiwara, Hitoshi; Shinagawa, Hiroyuki

    2017-04-01

    Using an atmosphere-ionosphere coupled model, the excitation source and temporal (seasonal and interannual) variations in non-migrating tides are investigated in this study. We first focus our attention on temporal variations in eastward moving diurnal tide with zonal wavenumber 3 (DE3), which is the largest of all the non-migrating tides in the mesosphere and lower thermosphere (MLT). Our simulation results indicate that upward propagation of the DE3 excited in the troposphere is sensitive to the zonal mean zonal wind in the stratosphere and mesosphere. The DE3 amplitude is enhanced in the region where the vertical shear of the zonal mean zonal wind is positive (westerly shear). Quasi-2-year variation in the DE3 amplitude in the MLT region is generated by quasi-2-year variation in the zonal mean zonal wind between 40 and 70 km, which is modulated by the stratospheric QBO. The excitation mechanisms of SW3 (westward moving semidiurnal tide with zonal wavenumber 3) and SW1 (westward moving semidiurnal tide with zonal wavenumber 1) are also investigated. During equinoxes, the SW3 and SW1 are excited by tropospheric heating (latent heat release and solar radiative heating) associated with cumulus convection in the tropics, and propagate upward into the MLT region. On the other hand, during solstices, SW3 and SW1 are generated in the winter stratosphere and mesosphere through the nonlinear interaction between the stationary planetary wave and migrating semidiurnal tide, and propagate upward to the lower thermosphere. The excitation sources of other non-migrating tides are also discussed.

  19. Public perceptions of Florida red tide risks.

    PubMed

    Kuhar, Sara E; Nierenberg, Kate; Kirkpatrick, Barbara; Tobin, Graham A

    2009-07-01

    This research integrates theoretical frameworks of risk perception, social amplification of risk, and the role of place-specific contexts in order to explore the various perceptions surrounding Florida red tides. Florida red tides are naturally occurring events that are increasing in frequency, duration, and severity. This has implications for public health, the local economy, and ecosystem health. While many of the negative impacts of Florida red tides are not easily controlled, some of the secondary impacts may be mitigated through individuals' responses. However, public perception and consequent reactions to Florida red tides have not been investigated. This research uses questionnaire surveys, and semi-structured interviews, to explore the various perceptions of the risk surrounding red tides. Surveys and interviews were conducted along two Florida west coast beaches. The results indicate that the underlying foundations of the social amplification of the risk framework are applicable to understanding how individuals form perceptions of risk relative to red tide events. There are key differences between the spatial locations of individuals and corresponding perceptions, indicating that place-specific contexts are essential to understanding how individuals receive and interpret risk information. The results also suggest that individuals may be lacking efficient and up-to-date information about Florida red tides and their impacts because of inconsistent public outreach. Overall, social and spatial factors appear to be influential as to whether individuals amplify or attenuate the risks associated with Florida red tides.

  20. Public Perceptions of Florida Red Tide Risks

    PubMed Central

    Kuhar, Sara E.; Nierenberg, Kate; Kirkpatrick, Barbara; Tobin, Graham A.

    2009-01-01

    This research integrates theoretical frameworks of risk perception, social amplification of risk, and the role of place-specific contexts in order to explore the various perceptions surrounding Florida red tides. Florida red tides are naturally occurring events that are increasing in frequency, duration, and severity. This has implications for public health, the local economy, and ecosystem health. While many of the negative impacts of Florida red tides are not easily controlled, some of the secondary impacts may be mitigated through individuals’ responses. However, public perception and consequent reactions to Florida red tides have not been investigated. This research uses questionnaire surveys, and semi-structured interviews, to explore the various perceptions of the risk surrounding red tides. Surveys and interviews were conducted along two Florida west coast beaches. The results indicate that the underlying foundations of the social amplification of the risk framework are applicable to understanding how individuals form perceptions of risk relative to red tide events. There are key differences between the spatial locations of individuals and corresponding perceptions, indicating that place-specific contexts are essential to understanding how individuals receive and interpret risk information. The results also suggest that individuals may be lacking efficient and up-to-date information about Florida red tides and their impacts because of inconsistent public outreach. Overall, social and spatial factors appear to be influential as to whether individuals amplify or attenuate the risks associated with Florida red tides. PMID:19392675

  1. Red Tide off Texas Coast

    NASA Technical Reports Server (NTRS)

    2002-01-01

    Red tides (algae) bloomed late this summer along a 300-mile stretch of Texas' Gulf Coast, killing millions of fish and shellfish as well as making some people sick. State officials are calling this the worst red tide bloom in 14 years. The algae produces a poison that paralyzes fish and prevents them from breathing. There is concern that the deadly algae could impact or even wipe out this year's oyster harvest in Texas, which usually peaks during the Thanksgiving and Christmas holidays. The red tides were first observed off the Texas coast in mid-August and have been growing steadily in size ever since. Red tides tend to bloom and subside rapidly, depending upon changes in wind speed and direction, water temperature, salinity, and rainfall patterns (as the algae doesn't do as well in fresher water). This true-color image of the Texas Gulf Coast was acquired on September 29, 2000, by the Moderate-resolution Imaging Spectroradiometer (MODIS) flying aboard NASA's Terra spacecraft. The red tide can be seen as the dark reddish discoloration in the ocean running southwest to northeast along the coast. In this scene, the bloom appears to be concentrated north and east of Corpus Christi, just off Matagorda Island. The image was made at 500-meter resolution using a combination of MODIS' visible bands 1 (red), 4 (green), and 3 (blue). The city of Houston can be seen clearly as the large, greyish cluster of pixels to the north and west of Galveston Bay, which is about mid-way up the coastline in this image. Also visible in this image are plumes of smoke, perhaps wildfires, both to the north and northeast of Houston. For more information about red tides, refer to the Texas Red Tide Web site. Image courtesy Andrey Savtchenko, MODIS Data Support Team, and the MODIS Ocean Team, NASA's Goddard Space Flight Center

  2. Using smartphones for monitoring atmospheric tides

    NASA Astrophysics Data System (ADS)

    Price, Colin; Maor, Ron; Shachaf, Hofit

    2018-09-01

    By 2020 there will be more than 6 billion smartphones around the globe, carried by the public. These smartphones are equipped with sensitive sensors that can be used to monitor our environment (temperature, pressure, humidity, magnetic field, etc.) In this paper we use the pressure sensor (barometer) within smartphones to study atmospheric tides. These tides are produced by the absorption of solar radiation by water vapor in the troposphere, and by ozone in the stratosphere. The strongest tides are the semi-diurnal tides (period of 12 h) with maximum pressure at 9am/9pm and minimum pressure at 3am/3pm. Given the proliferation of smartphones around the globe, this source of environmental data may become extremely useful for scientific research in the near future.

  3. Temporal variability of tidal and gravity waves during a record long 10-day continuous lidar sounding

    NASA Astrophysics Data System (ADS)

    Baumgarten, Kathrin; Gerding, Michael; Baumgarten, Gerd; Lübken, Franz-Josef

    2018-01-01

    Gravity waves (GWs) as well as solar tides are a key driving mechanism for the circulation in the Earth's atmosphere. The propagation of gravity waves is strongly affected by tidal waves as they modulate the mean background wind field and vice versa, which is not yet fully understood and not adequately implemented in many circulation models. The daylight-capable Rayleigh-Mie-Raman (RMR) lidar at Kühlungsborn (54° N, 12° E) typically provides temperature data to investigate both wave phenomena during one full day or several consecutive days in the middle atmosphere between 30 and 75 km altitude. Outstanding weather conditions in May 2016 allowed for an unprecedented 10-day continuous lidar measurement, which shows a large variability of gravity waves and tides on timescales of days. Using a one-dimensional spectral filtering technique, gravity and tidal waves are separated according to their specific periods or vertical wavelengths, and their temporal evolution is studied. During the measurement period a strong 24 h wave occurs only between 40 and 60 km and vanishes after a few days. The disappearance is related to an enhancement of gravity waves with periods of 4-8 h. Wind data provided by ECMWF are used to analyze the meteorological situation at our site. The local wind structure changes during the observation period, which leads to different propagation conditions for gravity waves in the last days of the measurement period and therefore a strong GW activity. The analysis indicates a further change in wave-wave interaction resulting in a minimum of the 24 h tide. The observed variability of tides and gravity waves on timescales of a few days clearly demonstrates the importance of continuous measurements with high temporal and spatial resolution to detect interaction phenomena, which can help to improve parametrization schemes of GWs in general circulation models.

  4. The Global S$_1$ Ocean Tide

    NASA Technical Reports Server (NTRS)

    Ray, Richard D.; Egbert, G. D.

    2003-01-01

    The small S$_1$ ocean tide is caused primarily by diurnal atmospheric pressure loading. Its excitation is therefore unlike any other diurnal tide. The global character of $S-1$ is here determined by numerical modeling and by analysis of Topex/Poseidon satellite altimeter data. The two approaches yield reasonably consistent results, and large ( $ greater than $l\\cm) amplitudes in several regions are further confirmed by comparison with coastal tide gauges. Notwithstanding their excitation differences, S$-1$ and other diurnal tides are found to share several common features, such as relatively large amplitudes in the Arabian Sea, the Sea of Okhotsk, and the Gulf of Alaska. The most noticeable difference is the lack of an S$-1$ Antarctic Kelvin wave. These similarities and differences can be explained in terms of the coherences between near-diurnal oceanic normal modes and the underlying tidal forcings. While gravitational diurnal tidal forces excite primarily a 28-hour Antarctic-Pacific mode, the S$_1$ air tide excites several other near-diurnal modes, none of which has large amplitudes near Antarctica.

  5. Harmonic analysis of tides and tidal currents in South San Francisco Bay, California

    USGS Publications Warehouse

    Cheng, R.T.; Gartner, J.W.

    1985-01-01

    Water level observations from tide stations and current observations from current-meter moorings in South San Francisco Bay (South Bay), California have been harmonically analysed. At each tide station, 13 harmonic constituents have been computed by a least-squares regression without inference. Tides in South Bay are typically mixed; there is a phase lag of approximately 1 h and an amplification of 1??5 from north to south for a mean semi-diurnal tide. Because most of the current-meter records are between 14 and 29 days, only the five most important harmonics have been solved for east-west and north-south velocity components. The eccentricity of tidal-current ellipse is generally very small, which indicates that the tidal current in South Bay is strongly bidirectional. The analyses further show that the principal direction and the magnitude of tidal current are well correlated with the basin bathymetry. Patterns of Eulerian residual circulation deduced from the current-meter data show an anticlockwise gyre to the west and a clockwise gyre to the east of the main channel in the summer months due to the prevailing westerly wind. Opposite trends have been observed during winter when the wind was variable. ?? 1985.

  6. Propagation Velocity of Solid Earth Tides

    NASA Astrophysics Data System (ADS)

    Pathak, S.

    2017-12-01

    One of the significant considerations in most of the geodetic investigations is to take into account the outcome of Solid Earth tides on the location and its consequent impact on the time series of coordinates. In this research work, the propagation velocity resulting from the Solid Earth tides between the Indian stations is computed. Mean daily coordinates for the stations have been computed by applying static precise point positioning technique for a day. The computed coordinates are used as an input for computing the tidal displacements at the stations by Gravity method along three directions at 1-minute interval for 24 hours. Further the baseline distances are computed between four Indian stations. Computation of the propagation velocity for Solid Earth tides can be done by the virtue of study of the concurrent effect of it in-between the stations of identified baseline distance along with the time consumed by the tides for reaching from one station to another. The propagation velocity helps in distinguishing the impact at any station if the consequence at a known station for a specific time-period is known. Thus, with the knowledge of propagation velocity, the spatial and temporal effects of solid earth tides can be estimated with respect to a known station. As theoretically explained, the tides generated are due to the position of celestial bodies rotating about Earth. So the need of study is to observe the correlation of propagation velocity with the rotation speed of the Earth. The propagation velocity of Solid Earth tides comes out to be in the range of 440-470 m/s. This velocity comes out to be in a good agreement with the Earth's rotation speed.

  7. GFDL's unified regional-global weather-climate modeling system with variable resolution capability for severe weather predictions and regional climate simulations

    NASA Astrophysics Data System (ADS)

    Lin, S. J.

    2015-12-01

    The NOAA/Geophysical Fluid Dynamics Laboratory has been developing a unified regional-global modeling system with variable resolution capabilities that can be used for severe weather predictions (e.g., tornado outbreak events and cat-5 hurricanes) and ultra-high-resolution (1-km) regional climate simulations within a consistent global modeling framework. The fundation of this flexible regional-global modeling system is the non-hydrostatic extension of the vertically Lagrangian dynamical core (Lin 2004, Monthly Weather Review) known in the community as FV3 (finite-volume on the cubed-sphere). Because of its flexability and computational efficiency, the FV3 is one of the final candidates of NOAA's Next Generation Global Prediction System (NGGPS). We have built into the modeling system a stretched (single) grid capability, a two-way (regional-global) multiple nested grid capability, and the combination of the stretched and two-way nests, so as to make convection-resolving regional climate simulation within a consistent global modeling system feasible using today's High Performance Computing System. One of our main scientific goals is to enable simulations of high impact weather phenomena (such as tornadoes, thunderstorms, category-5 hurricanes) within an IPCC-class climate modeling system previously regarded as impossible. In this presentation I will demonstrate that it is computationally feasible to simulate not only super-cell thunderstorms, but also the subsequent genesis of tornadoes using a global model that was originally designed for century long climate simulations. As a unified weather-climate modeling system, we evaluated the performance of the model with horizontal resolution ranging from 1 km to as low as 200 km. In particular, for downscaling studies, we have developed various tests to ensure that the large-scale circulation within the global varaible resolution system is well simulated while at the same time the small-scale can be accurately captured

  8. Tides in the Black Sea: Observations and Numerical Modelling

    NASA Astrophysics Data System (ADS)

    Medvedev, Igor P.

    2018-05-01

    Longterm hourly data from 28 tide gauges were used to examine the main features of tides in the Black Sea. The tides in this basin are directly caused by tide-generating forces and the semidiurnal tides prevail over diurnal tides. Based on the Princeton Ocean Model (POM), a numerical model of tides in the Black Sea and adjacent Sea of Azov was developed and found to be in good agreement with tide gauge observations. Detailed tidal charts for amplitudes and phase lags of the major tidal harmonics in these two seas were constructed. The results of the numerical modelling and observations reveal for the semidiurnal tides the presence of an amphidromy with clockwise rotation and another one with counterclockwise rotation for the diurnal tides, both located in the central part of the sea near the Crimean Peninsula. Therefore, for this part of the sea the amplitudes of harmonics M 2 and K 1 are less than 0.1 cm. Relatively larger M 2 amplitudes are observed on the east and west coasts of the sea (2-3 cm). The maximum amplitude of the harmonic M 2 was found at Karkinit Bay—up to 4.5 cm—while the maximum tidal range varies from 1 cm near the Crimean Peninsula to 18-19 cm in the Dnieper-Bug Estuary and Karkinit Bay. Radiational tides, initiated mainly by sea breezes, make an important contribution to the formation of tidal oscillations in the Dnieper-Bug Estuary.

  9. Dependence of Lunar Tide of the Equatorial Electrojet on the Wintertime Polar Vortex, Solar Flux, and QBO

    NASA Astrophysics Data System (ADS)

    Siddiqui, T. A.; Yamazaki, Y.; Stolle, C.; Lühr, H.; Matzka, J.; Maute, A.; Pedatella, N.

    2018-05-01

    The lower atmospheric forcing effects on the ionosphere are particularly evident during extreme meteorological events known as sudden stratospheric warmings (SSWs). During SSWs, the polar stratosphere and ionosphere, two distant atmospheric regions, are coupled through the SSW-induced modulation of atmospheric migrating and nonmigrating tides. The changes in the migrating semidiurnal solar and lunar tides are the major source of ionospheric variabilities during SSWs. In this study, we use 55 years of ground-magnetometer observations to investigate the composite characteristics of the lunar tide of the equatorial electrojet (EEJ) during SSWs. These long-term observations allow us to capture the EEJ lunar tidal response to the SSWs in a statistical sense. Further, we examine the influence of solar flux conditions and the phases of quasi-biennial oscillation (QBO) on the lunar tide and find that the QBO phases and solar flux conditions modulate the EEJ lunar tidal response during SSWs in a similar way as they modulate the wintertime Arctic polar vortex. This work provides first evidence of modulation of the EEJ lunar tide due to QBO.

  10. Energy, variability and weather finance engineering

    NASA Astrophysics Data System (ADS)

    Roussis, Dimitrios; Parara, Iliana; Gournari, Panagiota; Moustakis, Yiannis; Dimitriadis, Panayiotis; Iliopoulou, Theano; Koutsoyiannis, Demetris; Karakatsanis, Georgios

    2017-04-01

    Most types of renewable energies are characterized by intense intermittency, causing significant instabilities to the grid; further requiring additional infrastructure (e.g. pumped-storage) for buffering hydrometeorological uncertainties, as well as complex operational rules for load balancing. In addition, most intermittent renewable units are subsidized, creating significant market inefficiencies. Weather derivatives comprise mature financial tools for integrating successfully the intermittent-load and base-load components into a unified hybrid energy system and establish their operation within a generalized uncertainty management market. With a growing global market share and 46% utilization of this financial tool by the energy industry and 12% by agriculture (that partially concerns biofuel resources), weather derivatives are projected to constitute a critical subsystem of many grids for buffering frequent hydrometeorological risks of low and medium impacts -which are not covered by standard insurance contracts that aim exclusively at extreme events and high financial damages. In this context, we study the attributes of hydrometeorological time series in a remote and small island in Greece, powered by an autonomous hybrid energy system. Upon the results we choose the optimal underlying index and we further compose and engineer a weather derivative with features of a typical option contract -which we consider most flexible and appropriate for the case- to test our assumptions on its beneficiary effects for both the budget of private energy producers and the island's public administration. Acknowledgement: This research is conducted within the frame of the undergraduate course "Stochastic Methods in Water Resources" of the National Technical University of Athens (NTUA). The School of Civil Engineering of NTUA provided moral support for the participation of the students in the Assembly.

  11. Precise comparisons of bottom-pressure and altimetric ocean tides

    NASA Astrophysics Data System (ADS)

    Ray, R. D.

    2013-09-01

    A new set of pelagic tide determinations is constructed from seafloor pressure measurements obtained at 151 sites in the deep ocean. To maximize precision of estimated tides, only stations with long time series are used; median time series length is 567 days. Geographical coverage is considerably improved by use of the international tsunami network, but coverage in the Indian Ocean and South Pacific is still weak. As a tool for assessing global ocean tide models, the data set is considerably more reliable than older data sets: the root-mean-square difference with a recent altimetric tide model is approximately 5 mm for the M2 constituent. Precision is sufficiently high to allow secondary effects in altimetric and bottom-pressure tide differences to be studied. The atmospheric tide in bottom pressure is clearly detected at the S1, S2, and T2 frequencies. The altimetric tide model is improved if satellite altimetry is corrected for crustal loading by the atmospheric tide. Models of the solid body tide can also be constrained. The free core-nutation effect in the K1 Love number is easily detected, but the overall estimates are not as accurate as a recent determination with very long baseline interferometry.

  12. Precise Comparisons of Bottom-Pressure and Altimetric Ocean Tides

    NASA Technical Reports Server (NTRS)

    Ray, Richard D.

    2013-01-01

    A new set of pelagic tide determinations is constructed from seafloor pressure measurements obtained at 151 sites in the deep ocean. To maximize precision of estimated tides, only stations with long time series are used; median time series length is 567 days. Geographical coverage is considerably improved by use of the international tsunami network, but coverage in the Indian Ocean and South Pacific is still weak. As a tool for assessing global ocean tide models, the data set is considerably more reliable than older data sets : the root-mean-square difference with a recent altimetric tide model is approximately 5 mm for the M2 constituent. Precision is sufficiently high to allow secondary effects in altimetric and bottom-pressure tide differences to be studied. The atmospheric tide in bottom pressure is clearly detected at the S1, S2, and T2 frequencies. The altimetric tide model is improved if satellite altimetry is corrected for crustal loading by the atmospheric tide. Models of the solid body tide can also be constrained. The free corenutation effect in the K1 Love number is easily detected, but the overall estimates are not as accurate as a recent determination with very long baseline interferometry.

  13. New Miscellaneous Results in Tides from Topex/Poseidon

    NASA Technical Reports Server (NTRS)

    Ray, Richard D.; Egbert, G.; Cartwright, D.; Smith, David E. (Technical Monitor)

    2000-01-01

    This paper describes a variety of new results concerning ocean tides that have been derived from Topex/Poseidon satellite altimeter data. Most of these results are based on new tidal solutions employing nearly 8 years of data. The topics covered include internal tides and long-period tides.

  14. Solutions Network Formulation Report. Improving NOAA's Tides and Currents Through Enhanced Data Inputs from NASA's Ocean Surface Topography Mission

    NASA Technical Reports Server (NTRS)

    Guest, DeNeice C.

    2006-01-01

    The Nation uses water-level data for a variety of practical purposes, including hydrography, nautical charting, maritime navigation, coastal engineering, and tsunami and storm surge warnings (NOAA, 2002; Digby et al., 1999). Long-term applications include marine boundary determinations, tidal predictions, sea-level trend monitoring, oceanographic research, and climate research. Accurate and timely information concerning sea-level height, tide, and ocean current is needed to understand their impact on coastal management, disaster management, and public health. Satellite altimeter data products are currently used by hundreds of researchers and operational users to monitor ocean circulation and to improve scientists understanding of the role of the oceans in climate and weather. The NOAA (National Oceanic and Atmospheric Administration) National Ocean Service has been monitoring sea-level variations for many years (NOAA, 2006). NOAA s Tides & Currents DST (decision support tool, managed by the Center for Operational Oceanographic Products and Services, is the portal to a vast collection of oceanographic and meteorological data (historical and real-time), predictions, and nowcasts and forecasts. This report assesses the capacity of NASA s satellite altimeter data to meet societal decision support needs through incorporation into NOAA s Tides & Currents.

  15. Influence of weather and climate variables on the basal area growth of individual shortleaf pine trees

    Treesearch

    Pradip Saud; Thomas B. Lynch; Duncan S. Wilson; John Stewart; James M. Guldin; Bob Heinemann; Randy Holeman; Dennis Wilson; Keith Anderson

    2015-01-01

    An individual-tree basal area growth model previously developed for even-aged naturally occurring shortleaf pine trees (Pinus echinata Mill.) in western Arkansas and southeastern Oklahoma did not include weather variables. Individual-tree growth and yield modeling of shortleaf pine has been carried out using the remeasurements of over 200 plots...

  16. Effects of Weather Variables on Ascospore Discharge from Fusarium graminearum Perithecia

    PubMed Central

    Manstretta, Valentina; Rossi, Vittorio

    2015-01-01

    Fusarium graminearum is a predominant component of the Fusarium head blight (FHB) complex of small grain cereals. Ascosporic infection plays a relevant role in the spread of the disease. A 3-year study was conducted on ascospore discharge. To separate the effect of weather on discharge from the effect of weather on the production and maturation of ascospores in perithecia, discharge was quantified with a volumetric spore sampler placed near maize stalk residues bearing perithecia with mature ascospores; the residues therefore served as a continuous source of ascospores. Ascospores were discharged from perithecia on 70% of 154 days. Rain (R) and vapor pressure deficit (VPD) were the variables that most affected ascospore discharge, with 84% of total discharges occurring on days with R≥0.2 mm or VPD≤11 hPa, and with 70% of total ascospore discharge peaks (≥ 30 ascospores/m3 air per day) occurring on days with R≥0.2 mm and VPD≤6.35 hPa. An ROC analysis using these criteria for R and VPD provided True Positive Proportion (TPP) = 0.84 and True Negative Proportion (TNP) = 0.63 for occurrence of ascospore discharge, and TPP = 0.70 and TNP = 0.89 for occurrence of peaks. Globally, 68 ascospores (2.5% of the total ascospores sampled) were trapped on the 17 days when no ascospores were erroneously predicted. When a discharge occurred, the numbers of F. graminearum ascospores sampled were predicted by a multiple regression model with R2 = 0.68. This model, which includes average and maximum temperature and VPD as predicting variables, slightly underestimated the real data and especially ascospore peaks. Numbers of ascospores in peaks were best predicted by wetness duration of the previous day, minimum temperature, and VPD, with R2 = 0.71. These results will help refine the epidemiological models used as decision aids in FHB management programs. PMID:26402063

  17. The "Mars-Sun Connection" and the Impact of Solar Variability on Mars Weather and Climate

    NASA Astrophysics Data System (ADS)

    Hassler, D. M.; Grinspoon, D.

    2004-05-01

    We develop the scientific case to measure simultaneously the UV and near-UV solar irradiance incident on the Mars atmosphere and at the Martian surface, to explore the effects and influence of Solar variability and "Space Weather" on Mars weather and climate, its implications for life, and the implications for astronaut safety on future manned Mars missions. The UV flux at the Martian surface is expected to be highly variable, due to diurnal, daily, and seasonal variations in opacity of atmospheric dust and clouds, as well as diurnal and seasonal variations in ozone, water vapor and other absorbing species. This flux has been modeled (Kuhn and Atreya, 1979), but never measured directly from the Martian surface. By directly observing the UV and near UV solar irradiance both at the top of the atmosphere and at the Martian surface we will be able to directly constrain important model parameters necessary to understand the variations of atmospheric dynamics which drive both Mars weather and climate. Directly measuring the solar UV radiation incident upon the Mars atmosphere and at the Martian surface also has important implications for astronaut safety on future manned Mars missions. The flux at the surface of Mars at 250 nm is also believed to be approximately 3000 times greater than that on Earth. This presents potential hazards to future human explorers as well as challenges for future agriculture such as may be carried out in surface greenhouses to provide food for human colonists. A better understanding of the surface flux will aid in designing appropriate protection against these hazards.

  18. The ``Mars-Sun Connection" and the Impact of Solar Variability on Mars Weather and Climate

    NASA Astrophysics Data System (ADS)

    Hassler, D. M.; Grinspoon, D. H.

    2003-05-01

    We develop the scientific case to measure simultaneously the UV and near-UV solar irradiance incident on the Mars atmosphere and at the Martian surface, to explore the effects and influence of Solar variability and ``Space Weather" on Mars weather and climate, its implications for life, and the implications for astronaut safety on future manned Mars missions. The UV flux at the Martian surface is expected to be highly variable, due to diurnal, daily, and seasonal variations in opacity of atmospheric dust and clouds, as well as diurnal and seasonal variations in ozone, water vapor and other absorbing species. This flux has been modeled (Kuhn and Atreya, 1979), but never measured directly from the Martian surface. By directly observing the UV and near UV solar irradiance both at the top of the atmosphere and at the Martian surface we will be able to directly constrain important model parameters necessary to understand the variations of atmospheric dynamics which drive both Mars weather and climate. Directly measuring the solar UV radiation incident upon the Mars atmosphere and at the Martian surface also has important implications for astronaut safety on future manned Mars missions. The flux at the surface of Mars at 250 nm is also believed to be approximately 3000 times greater than that on Earth. This presents potential hazards to future human explorers as well as challenges for future agriculture such as may be carried out in surface greenhouses to provide food for human colonists. A better understanding of the surface flux will aid in designing appropriate protection against these hazards.

  19. Internal tides in the Solomon Sea

    NASA Astrophysics Data System (ADS)

    Lionel, Tchilibou Michel; Gourdeau, Lionel; Djath, Bugshin; Lyard, Florent; Allain, Damien; Koch Larrouy, Ariane; Yoga Nogroho, Dwi; Morrow, Rosemary

    2017-04-01

    In the south west Pacific, the Solomon Sea lies on the pathway of the Low Latitudes Western Boundary Currents (LLWBCs) that connect the subtropics to the equator. The Solomon Sea have a particular interest in a climatic context, since they are a critical pathway for ENSO and its low frequency modulation. The western Pacific is a place of energetic internal tides generated over its complex bottom topographic features. In the Indonesian Archipelago, they are particularly active in defining the properties of the waters that move from the Pacific to the Indian Ocean. The salinity maximum at the thermocline level, which is characteristic of the South Pacific Tropical Waters (SPTW) flowing within the LLWBCs and feeding the Equatorial UnderCurrent, is largely eroded within the Solomon Sea. Different mechanisms could explain such salt erosion including current/bathymetry interactions, internal tides, and eddy activity. The motivation of this study is to investigate the potential role of internal tides for such water mass transformation. Results from a 1/36° resolution regional model including explicit tides are presented. As a first step, the generation and propagation of internal tides in the Solomon Sea are determined, and the conversion rate from barotropic to baroclinic energy is estimated.

  20. Influences of rainfall variables and antecedent discharge on urban effluent concentrations and loads in wet weather.

    PubMed

    Xu, Zuxin; Xiong, Lijun; Li, Huaizheng; Liao, Zhengliang; Yin, Hailong; Wu, Jun; Xu, Jin; Chen, Hao

    2017-04-01

    For storm drainages inappropriately connected with sewage, wet weather discharge is a major factor that adversely affects receiving waters. A study of the wet weather influences of rainfall-discharge variables on storm drainages connected with sewage was conducted in the downtown Shanghai area (374 ha). Two indicators, event mean concentration (EMC) and event pollutant load per unit area (EPL), were used to describe the pollution discharge during 20 rain events. The study showed that the total rainfall and discharge volume were important factors that affect the EMCs and EPLs of the chemical oxygen demand, total phosphorus, and especially those of NH 4 + -N. The pollutant concentrations at the beginning of the discharge and the discharge period were also major factors that influence the EMCs of these three pollutants. Regression relationships between the rainfall-discharge variables and discharge volume/ EPLs (R 2 = 0.824-0.981) were stronger than the relationships between the rainfall-discharge variables and EMCs. These regression equations can be considered reliable in the system, with a relative validation error of less than ±10% for the discharge volume, and less than ±20% for the EPLs. The results presented in this paper provide guidance for effectively controlling pollution in similar storm drainages.

  1. Bottom friction optimization for a better barotropic tide modelling

    NASA Astrophysics Data System (ADS)

    Boutet, Martial; Lathuilière, Cyril; Son Hoang, Hong; Baraille, Rémy

    2015-04-01

    At a regional scale, barotropic tides are the dominant source of variability of currents and water heights. A precise representation of these processes is essential because of their great impacts on human activities (submersion risks, marine renewable energies, ...). Identified sources of error for tide modelling at a regional scale are the followings: bathymetry, boundary forcing and dissipation due to bottom friction. Nevertheless, bathymetric databases are nowadays known with a good accuracy, especially over shelves, and global tide models performances are better than ever. The most promising improvement is thus the bottom friction representation. The method used to estimate bottom friction is the simultaneous perturbation stochastic approximation (SPSA) which consists in the approximation of the gradient based on a fixed number of cost function measurements, regardless of the dimension of the vector to be estimated. Indeed, each cost function measurement is obtained by randomly perturbing every component of the parameter vector. An important feature of SPSA is its relative ease of implementation. In particular, the method does not require the development of tangent linear and adjoint version of the circulation model. Experiments are carried out to estimate bottom friction with the HYbrid Coordinate Ocean Model (HYCOM) in barotropic mode (one isopycnal layer). The study area is the Northeastern Atlantic margin which is characterized by strong currents and an intense dissipation. Bottom friction is parameterized with a quadratic term and friction coefficient is computed with the water height and the bottom roughness. The latter parameter is the one to be estimated. Assimilated data are the available tide gauge observations. First, the bottom roughness is estimated taking into account bottom sediment natures and bathymetric ranges. Then, it is estimated with geographical degrees of freedom. Finally, the impact of the estimation of a mixed quadratic/linear friction

  2. What can earth tide measurements tell us about ocean tides or earth structure?

    NASA Technical Reports Server (NTRS)

    Baker, T. F.

    1978-01-01

    Current experimental problems in Earth tides are reviewed using comparisons of tidal gravity and tilt measurements in Europe with loading calculations are examples. The limitations of present day instrumentation and installation techniques are shown as well as some of the ways in which they can be improved. Many of the geophysical and oceanographic investigations that are possible with Earth tide measurements are discussed with emphasis on the percentage accuracies required in the measurements in order to obtain new information about Earth or its oceans.

  3. The Application of Synoptic Weather Forecasting Rules to Selected Weather Situations in the United States.

    ERIC Educational Resources Information Center

    Kohler, Fred E.

    The document describes the use of weather maps and data in teaching introductory college courses in synoptic meteorology. Students examine weather changes at three-hour intervals from data obtained from the "Monthly Summary of Local Climatological Data." Weather variables in the local summary include sky cover, air temperature, dew point, relative…

  4. Ocean Tide Loading Computation

    NASA Technical Reports Server (NTRS)

    Agnew, Duncan Carr

    2005-01-01

    September 15,2003 through May 15,2005 This grant funds the maintenance, updating, and distribution of programs for computing ocean tide loading, to enable the corrections for such loading to be more widely applied in space- geodetic and gravity measurements. These programs, developed under funding from the CDP and DOSE programs, incorporate the most recent global tidal models developed from Topex/Poscidon data, and also local tide models for regions around North America; the design of the algorithm and software makes it straightforward to combine local and global models.

  5. Fortnightly Ocean Tides, Earth Rotation, and Mantle Anelasticity

    NASA Technical Reports Server (NTRS)

    Ray, Richard; Egbert, Gary

    2012-01-01

    The fortnightly Mf ocean tide is the largest of the long-period tides (periods between 1 week and 18.6 years), but Mf is still very small, generally 2 cm or less. All long-period tides are thought to be near equilibrium with the astronomical tidal potential, with an almost pure zonal structure. However, several lines of evidence point to Mf having a significant dynamic response to forcing. We use a combination of numerical modeling, satellite altimetry, and observations of polar motion to determine the Mf ocean tide and to place constraints on certain global properties, such as angular momentum. Polar motion provides the only constraints on Mf tidal currents. With a model of the Mf ocean tide in hand, we use it to remove the effects of the ocean from estimates of fortnightly variations in length-of-day. The latter is dominated by the earth's body tide, but a small residual allows us to place new constraints on the anelasticity of the earth's mantle. The result gives the first experimental confirmation of theoretical predictions made by Wahr and Bergen in 1986.

  6. A comparison of weather variables linked to infectious disease patterns using laboratory addresses and patient residence addresses.

    PubMed

    Djennad, Abdelmajid; Lo Iacono, Giovanni; Sarran, Christophe; Fleming, Lora E; Kessel, Anthony; Haines, Andy; Nichols, Gordon L

    2018-04-27

    To understand the impact of weather on infectious diseases, information on weather parameters at patient locations is needed, but this is not always accessible due to confidentiality or data availability. Weather parameters at nearby locations are often used as a proxy, but the accuracy of this practice is not known. Daily Campylobacter and Cryptosporidium cases across England and Wales were linked to local temperature and rainfall at the residence postcodes of the patients and at the corresponding postcodes of the laboratory where the patient's specimen was tested. The paired values of daily rainfall and temperature for the laboratory versus residence postcodes were interpolated from weather station data, and the results were analysed for agreement using linear regression. We also assessed potential dependency of the findings on the relative geographic distance between the patient's residence and the laboratory. There was significant and strong agreement between the daily values of rainfall and temperature at diagnostic laboratories with the values at the patient residence postcodes for samples containing the pathogens Campylobacter or Cryptosporidium. For rainfall, the R-squared was 0.96 for the former and 0.97 for the latter, and for maximum daily temperature, the R-squared was 0.99 for both. The overall mean distance between the patient residence and the laboratory was 11.9 km; however, the distribution of these distances exhibited a heavy tail, with some rare situations where the distance between the patient residence and the laboratory was larger than 500 km. These large distances impact the distributions of the weather variable discrepancies (i.e. the differences between weather parameters estimated at patient residence postcodes and those at laboratory postcodes), with discrepancies up to ±10 °C for the minimum and maximum temperature and 20 mm for rainfall. Nevertheless, the distributions of discrepancies (estimated separately for minimum and maximum

  7. Weather variables and the El Niño Southern Oscillation may drive the epidemics of dengue in Guangdong Province, China.

    PubMed

    Xiao, Jianpeng; Liu, Tao; Lin, Hualiang; Zhu, Guanghu; Zeng, Weilin; Li, Xing; Zhang, Bing; Song, Tie; Deng, Aiping; Zhang, Meng; Zhong, Haojie; Lin, Shao; Rutherford, Shannon; Meng, Xiaojing; Zhang, Yonghui; Ma, Wenjun

    2018-05-15

    To investigate the periodicity of dengue and the relationship between weather variables, El Niño Southern Oscillation (ENSO) and dengue incidence in Guangdong Province, China. Guangdong monthly dengue incidence and weather data and El Niño index information for 1988 to 2015 were collected. Wavelet analysis was used to investigate the periodicity of dengue, and the coherence and time-lag phases between dengue and weather variables and ENSO. The Generalized Additive Model (GAM) approach was further employed to explore the dose-response relationship of those variables on dengue. Finally, random forest analysis was applied to measure the relative importance of the climate predictors. Dengue in Guangdong has a dominant annual periodicity over the period 1988-2015. Mean minimum temperature, total precipitation, and mean relative humidity are positively related to dengue incidence for 2, 3, and 4months lag, respectively. ENSO in the previous 12months may have driven the dengue epidemics in 1995, 2002, 2006 and 2010 in Guangdong. GAM analysis indicates an approximate linear association for the temperature-dengue relationship, approximate logarithm curve for the humidity-dengue relationship, and an inverted U-shape association for the precipitation-dengue (the threshold of precipitation is 348mm per month) and ENSO-dengue relationships (the threshold of ENSO index is 0.6°C). The monthly mean minimum temperature in the previous two months was identified as the most important climate variable associated with dengue epidemics in Guangdong Province. Our study suggests weather factors and ENSO are important predictors of dengue incidence. These findings provide useful evidence for early warning systems to help to respond to the global expansion of dengue fever. Copyright © 2017 Elsevier B.V. All rights reserved.

  8. Tides and Trends in Higher Education.

    ERIC Educational Resources Information Center

    Fincher, Cameron

    This paper examines changes in American higher education, using the metaphor of ocean tides. The tides of change in the 1980s included public demands for assessment and accountability; fairness and credibility in advantages and benefits; improved quality of education; effectiveness and efficiency; assurance that college graduates were personally…

  9. The effects of low-tide rainfall on metal content of suspended sediment in the Sacramento-San Joaquin Delta

    NASA Astrophysics Data System (ADS)

    Moskalski, S. M.; Torres, R.; Bizimis, M.; Bergamaschi, B. A.; Fleck, J.; Goni, M. A.

    2012-12-01

    Rain falling near low tide is capable of eroding and transporting cohesive sediment from marsh and mudflat surfaces. Given that metals adsorb strongly to silt- and clay-sized particles, it is conceivable that lowtide rainfall may also liberate previously-deposited metals from storage in intertidal sediment. To investigate the potential for rainfall as an agent of remobilization of metals, this study tested the hypothesis of sediment, and therefore metals and nutrients, mobilization during these punctuated low-tide rainfall events. Water samples were collected during low-tide rain events in winter and wind resuspension events in summer from a marsh in central California. The concentrations of suspended sediment, particulate organic carbon and nitrogen, and total adsorbed concentration (mass of metal per volume of filtered water) of most metals were higher during a low tide rainfall event than during wind-only and fair-weather events. Metal contents (mass of metal per mass of sediment) were also greater during the rain event for most metals. Principle components analysis and the relationships between total adsorbed metals and SSC suggest rainfall during low tide can mobilize a different source of sediment than the background sediment available for tidal and wind-wave resuspension. The metal content of bulk sediment samples from around the study area could not be matched satisfactorily to the suspended sediment in any of the events, implying that bulk sediment should not be used to extrapolate to suspended sediment in terms of adsorbed metal content. Some of the adsorbed metals were present during the rain event in amounts that could be toxic, depending on the actual bioavailability of the metals.; Summary plots of measured organic parameters. (A) POC (B) PN (C) C:N (D) total leachable metal concentration, sum of all measured metals. The solid line inside box is the median and the dashed line is the mean.

  10. Dynamic ocean-tide effects on Earth's rotation

    NASA Technical Reports Server (NTRS)

    Dickman, S. R.

    1993-01-01

    This article develops 'broad-band' Liouville equations which are capable of determining the effects on the rotation of the Earth of a periodic excitation even at frequencies as high as semi-diurnal; these equations are then used to predict the rotational effects of altimetric, numerical and 32-constituent spherical harmonic ocean-tide models. The rotational model includes a frequency-dependent decoupled core, the effects of which are especially marked near retrograde diurnal frequencies; and a fully dynamic oceanic response, whose effects appear to be minor despite significant frequency dependence. The model also includes solid-earth effects which are frequency dependent as the result of both anelasticity at long periods and the fluid-core resonance at nearly diurnal periods. The effects of both tidal inertia and relative angular momentum on Earth rotation (polar motion, length of day, 'nutation' and Universal Time) are presented for 32 long- and short-period ocean tides determined as solutions to the author's spherical harmonic tide theory. The lengthening of the Chandler wobble period by the pole tide is also re-computed using the author's full theory. Additionally, using the spherical harmonic theory, tidal currents and their effects on rotation are determined for available numerical and altimetric tide height models. For all models, we find that the effects of tidal currents are at least as important as those of tide height for diurnal and semi-diurnal constituents.

  11. Considerations in the weathering of wood-plastic composites

    Treesearch

    Nicole M. Stark

    2007-01-01

    During weathering, wood-plastic composites (WPCs) can fade and lose stiffness and strength. Weathering variables that induce these changes include exposure to UV light and water. Each variable degrades WPCs independently, but can also act synergistically. Recent efforts have highlighted the need to understand how WPCs weather, and to develop schemes for protection. The...

  12. The magnetic tides of Honolulu

    USGS Publications Warehouse

    Love, Jeffrey J.; Rigler, Erin Joshua

    2013-01-01

    We review the phenomenon of time-stationary, periodic quiet-time geomagnetic tides. These are generated by the ionospheric and oceanic dynamos, and, to a lesser-extent, by the quiet-time magnetosphere, and they are affected by currents induced in the Earth's electrically conducting interior. We examine historical time series of hourly magnetic-vector measurements made at the Honolulu observatory. We construct high-resolution, frequency-domain Lomb-periodogram and maximum-entropy power spectra that reveal a panorama of stationary harmonics across periods from 0.1 to 10000.0-d, including harmonics that result from amplitude and phase modulation. We identify solar-diurnal tides and their annual and solar-cycle sideband modulations, lunar semi-diurnal tides and their solar-diurnal sidebands, and tides due to precession of lunar eccentricity and nodes. We provide evidence that a method intended for separating the ionospheric and oceanic dynamo signals by midnight subsampling of observatory data time series is prone to frequency-domain aliasing. The tidal signals we summarize in this review can be used to test our fundamental understanding of the dynamics of the quiet-time ionosphere and magnetosphere, induction in the ocean and in the electrically conducting interior of the Earth, and they are useful for defining a quiet-time baseline against which magnetospheric-storm intensity is measured.

  13. Variability of O2, H2S, and pH in intertidal sediments measured on a highly resolved spatial and temporal scale

    NASA Astrophysics Data System (ADS)

    Walpersdorf, E.; Werner, U.; Bird, P.; de Beer, D.

    2003-04-01

    We investigated the variability of O_2, pH, and H_2S in intertidal sediments to assess the time- and spatial scales of changes in environmental conditions and their effects on bacterial activities. Measurements were performed over the tidal cycle and at different seasons by the use of microsensors attached to an autonomous in-situ measuring device. This study was carried out at a sand- and a mixed flat in the backbarrier area of Spiekeroog (Germany) within the frame of the DFG research group "Biogeochemistry of the Wadden Sea". Results showed that O_2 variability was not pronounced in the coastal mixed flat, where only extreme weather conditions could increase O_2 penetration. In contrast, strong dynamics in O_2 availability, pH and maximum penetration depths of several cm were found at the sandflat. In these highly permeable sediments, we directly observed tidal pumping: at high tide O_2-rich water was forced into the plate and at low tide anoxic porewater drained off the sediment. From the lower part of the plate where organic rich clayey layers were embedded in the sediment anoxic water containing H_2S leaked out during low tide. Thus advective processes, driven by the tidal pump, waves and currents, control O_2 penetration and depth distribution of H_2S and pH. The effects of the resulting porewater exchange on mineralization rates and microbial activities will be discussed.

  14. Geodynamic Effects of Ocean Tides: Progress and Problems

    NASA Technical Reports Server (NTRS)

    Richard, Ray

    1999-01-01

    Satellite altimetry, particularly Topex/Poseidon, has markedly improved our knowledge of global tides, thereby allowing significant progress on some longstanding problems in geodynamics. This paper reviews some of that progress. Emphasis is given to global-scale problems, particularly those falling within the mandate of the new IERS Special Bureau for Tides: angular momentum, gravitational field, geocenter motion. For this discussion I use primarily the new ocean tide solutions GOT99.2, CSR4.0, and TPXO.4 (for which G. Egbert has computed inverse-theoretic error estimates), and I concentrate on new results in angular momentum and gravity and their solid-earth implications. One example is a new estimate of the effective tidal Q at the M_2 frequency, based on combining these ocean models with tidal estimates from satellite laser ranging. Three especially intractable problems are also addressed: (1) determining long-period tides in the Arctic [large unknown effect on the inertia tensor, particularly for Mf]; (2) determining the global psi_l tide [large unknown effect on interpretations of gravimetry for the near-diurnal free wobble]; and (3) determining radiational tides [large unknown temporal variations at important frequencies]. Problems (2) and (3) are related.

  15. Rock Erodibility as a Dynamic Variable Driven by the Interplay between Erosion and Weathering in Bedrock Channels: Examples from Great Falls, Virginia, USA

    NASA Astrophysics Data System (ADS)

    Hancock, G. S.; Huettenmoser, J.; Shobe, C. M.; Eppes, M. C.

    2016-12-01

    Rock erodibility in channels is a primary control on the stresses required to erode bedrock (e.g., Sklar and Dietrich, 2001). Erodibility tends to be treated as a uniform and fixed variable at the scale of channel cross-sections, particularly in models of channel profile evolution. Here we present field data supporting the hypothesis (Hancock et al., 2011) that erodibility is a dynamic variable, driven by the interplay between erosion rate and weathering processes within cross-sections. We hypothesize that rock weathering varies in cross-sections from virtually unweathered in the thalweg, where frequent stripping removes weathered rock, to a degree of weathering determined by the frequency of erosive events higher on the channel margin. We test this hypothesis on three tributaries to the Potomac River underlain by similar bedrock but with varying erosion rates ( 0.01 to 0.8 m/ky). At multiple heights within three cross-sections on three tributaries, we measured compressive strength with a Schmidt hammer, surface roughness with a contour gage, and density and length of visible cracks. Compressive strength decreased with height in all nine cross-sections by 10% to 50%, and surface roughness increased with height in seven cross-sections by 25% - 45%, with the remaining two showing minimal change. Crack density increased with height in the three cross-sections measured. Taken together these data demonstrate increases in weathering intensity, and presumably, rock erodibility, with height. The y-intercept of the relation between height and the three measured variables were nearly identical, suggesting that thalweg erodibility was similar on each channel, as predicted, even though erodibility higher in the cross-section were markedly different. The rate at which the three variables changed with height in each cross-section is strongly related to stream power. Assuming stream power is a reasonable surrogate for erosion rate, this result implies that erosion rate can be a

  16. Impact of sea level rise on tide gate function.

    PubMed

    Walsh, Sean; Miskewitz, Robert

    2013-01-01

    Sea level rise resulting from climate change and land subsidence is expected to severely impact the duration and associated damage resulting from flooding events in tidal communities. These communities must continuously invest resources for the maintenance of existing structures and installation of new flood prevention infrastructure. Tide gates are a common flood prevention structure for low-lying communities in the tidal zone. Tide gates close during incoming tides to prevent inundation from downstream water propagating inland and open during outgoing tides to drain upland areas. Higher downstream mean sea level elevations reduce the effectiveness of tide gates by impacting the hydraulics of the system. This project developed a HEC-RAS and HEC-HMS model of an existing tide gate structure and its upland drainage area in the New Jersey Meadowlands to simulate the impact of rising mean sea level elevations on the tide gate's ability to prevent upstream flooding. Model predictions indicate that sea level rise will reduce the tide gate effectiveness resulting in longer lasting and deeper flood events. The results indicate that there is a critical point in the sea level elevation for this local area, beyond which flooding scenarios become dramatically worse and would have a significantly negative impact on the standard of living and ability to do business in one of the most densely populated areas of America.

  17. How reliable is the offline linkage of Weather Research & Forecasting Model (WRF) and Variable Infiltration Capacity (VIC) model?

    EPA Science Inventory

    The aim for this research is to evaluate the ability of the offline linkage of Weather Research & Forecasting Model (WRF) and Variable Infiltration Capacity (VIC) model to produce hydrological, e.g. evaporation (ET), soil moisture (SM), runoff, and baseflow. First, the VIC mo...

  18. Possible forcing of global temperature by the oceanic tides

    PubMed Central

    Keeling, Charles D.; Whorf, Timothy P.

    1997-01-01

    An approximately decadal periodicity in surface air temperature is discernable in global observations from A.D. 1855 to 1900 and since A.D. 1945, but with a periodicity of only about 6 years during the intervening period. Changes in solar irradiance related to the sunspot cycle have been proposed to account for the former, but cannot account for the latter. To explain both by a single mechanism, we propose that extreme oceanic tides may produce changes in sea surface temperature at repeat periods, which alternate between approximately one-third and one-half of the lunar nodal cycle of 18.6 years. These alternations, recurring at nearly 90-year intervals, reflect varying slight degrees of misalignment and departures from the closest approach of the Earth with the Moon and Sun at times of extreme tide raising forces. Strong forcing, consistent with observed temperature periodicities, occurred at 9-year intervals close to perihelion (solar perigee) for several decades centered on A.D. 1881 and 1974, but at 6-year intervals for several decades centered on A.D. 1923. As a physical explanation for tidal forcing of temperature we propose that the dissipation of extreme tides increases vertical mixing of sea water, thereby causing episodic cooling near the sea surface. If this mechanism correctly explains near-decadal temperature periodicities, it may also apply to variability in temperature and climate on other times-scales, even millennial and longer. PMID:11607740

  19. Impact of selected personal factors on seasonal variability of recreationist weather perceptions and preferences in Warsaw (Poland)

    NASA Astrophysics Data System (ADS)

    Lindner-Cendrowska, Katarzyna; Błażejczyk, Krzysztof

    2018-01-01

    Weather and climate are important natural resources for tourism and recreation, although sometimes they can make outdoor leisure activities less satisfying or even impossible. The aim of this work was to determine weather perception seasonal variability of people staying outdoors in urban environment for tourism and recreation, as well as to determine if personal factors influence estimation of recreationist actual biometeorological conditions and personal expectations towards weather elements. To investigate how human thermal sensations vary upon meteorological conditions typical for temperate climate, weather perception field researches were conducted in Warsaw (Poland) in all seasons. Urban recreationists' preference for slightly warm thermal conditions, sunny, windless and cloudless weather, were identified as well as PET values considered to be optimal for sightseeing were defined between 27.3 and 31.7 °C. The results confirmed existence of phenomena called alliesthesia, which manifested in divergent thermal perception of comparable biometeorological conditions in transitional seasons. The results suggest that recreationist thermal sensations differed from other interviewees' responses and were affected not only by physiological processes but they were also conditioned by psychological factors (i.e. attitude, expectations). Significant impact of respondents' place of origin and its climate on creating thermal sensations and preferences was observed. Sex and age influence thermal preferences, whereas state of acclimatization is related with thermal sensations to some point.

  20. Impact of selected personal factors on seasonal variability of recreationist weather perceptions and preferences in Warsaw (Poland).

    PubMed

    Lindner-Cendrowska, Katarzyna; Błażejczyk, Krzysztof

    2018-01-01

    Weather and climate are important natural resources for tourism and recreation, although sometimes they can make outdoor leisure activities less satisfying or even impossible. The aim of this work was to determine weather perception seasonal variability of people staying outdoors in urban environment for tourism and recreation, as well as to determine if personal factors influence estimation of recreationist actual biometeorological conditions and personal expectations towards weather elements. To investigate how human thermal sensations vary upon meteorological conditions typical for temperate climate, weather perception field researches were conducted in Warsaw (Poland) in all seasons. Urban recreationists' preference for slightly warm thermal conditions, sunny, windless and cloudless weather, were identified as well as PET values considered to be optimal for sightseeing were defined between 27.3 and 31.7 °C. The results confirmed existence of phenomena called alliesthesia, which manifested in divergent thermal perception of comparable biometeorological conditions in transitional seasons. The results suggest that recreationist thermal sensations differed from other interviewees' responses and were affected not only by physiological processes but they were also conditioned by psychological factors (i.e. attitude, expectations). Significant impact of respondents' place of origin and its climate on creating thermal sensations and preferences was observed. Sex and age influence thermal preferences, whereas state of acclimatization is related with thermal sensations to some point.

  1. Coastal sea level variability in the eastern English Channel: Potentialities for future SWOT applicability

    NASA Astrophysics Data System (ADS)

    Turki, Imen; Laignel, Benoit; Chevalier, Laetitia; Costa, Stephane

    2014-05-01

    Scientists and engineers need to understand the sea level variability in order to provide better estimates of the sea level rise for coastal defense using tide gauges and radar altimetry missions. The natural limitation of the tide gauge records is their geographical sparsity and confinement to coastlines. The future Surface Water and Ocean Topography (SWOT) mission will be launched in 2015 over a period of 5 years and will be designated to address this issue. This research was carried out in the framework of the program Surface Water and Ocean Topography (SWOT) which is a partnership between NASA and CNES. Using a series of statistical analyses, we point to characterize the sea level variability in the eastern English Channel (western France) from four tide gauges in Dunkirk, Dieppe, Le Havre and Cherbourg for the period 1964-2012. To assess the extent to which tide gauge point observations represent tide gauge data, we compare tide gauge records to SWOT measurements in their vicinity. Results have shown that the bimodality of the sea level, provided by the distribution analysis, can be reproduced by SWOT measurements with an overestimation of both modes and also the extreme values. The rate of the linear regression was also overestimated from 1.7-4 mm/yr to 2.6-5.4 mm/yr. The continuous wavelet transform of sea level records has shown the large-scale variability of annual (1-year band) and interannual cycles (2-6- and 6-12-year bands) in sea level, which can be explained by oceanographic and hydrological factors. High frequency dynamics of the sea level variability at short time-scales were extracted from SWOT measurements. They provide a good survey of the surge events (band of 3-4 months) and the spring-neap tidal cycle (band of 28 days). Then, tide gauges should be used in conjunction with satellite data to infer the full time-scale variability. Further studies are needed to refine the SWOT applicability in coastal areas. Key words: coastal zone, sea level

  2. Daily estimates of the migrating tide and zonal mean temperature in the mesosphere and lower thermosphere derived from SABER data

    NASA Astrophysics Data System (ADS)

    Ortland, David A.

    2017-04-01

    Satellites provide a global view of the structure in the fields that they measure. In the mesosphere and lower thermosphere, the dominant features in these fields at low zonal wave number are contained in the zonal mean, quasi-stationary planetary waves, and tide components. Due to the nature of the satellite sampling pattern, stationary, diurnal, and semidiurnal components are aliased and spectral methods are typically unable to separate the aliased waves over short time periods. This paper presents a data processing scheme that is able to recover the daily structure of these waves and the zonal mean state. The method is validated by using simulated data constructed from a mechanistic model, and then applied to Sounding of the Atmosphere using Broadband Emission Radiometry (SABER) temperature measurements. The migrating diurnal tide extracted from SABER temperatures for 2009 has a seasonal variability with peak amplitude (20 K at 95 km) in February and March and minimum amplitude (less than 5 K at 95 km) in early June and early December. Higher frequency variability includes a change in vertical structure and amplitude during the major stratospheric warming in January. The migrating semidiurnal tide extracted from SABER has variability on a monthly time scale during January through March, minimum amplitude in April, and largest steady amplitudes from May through September. Modeling experiments were performed that show that much of the variability on seasonal time scales in the migrating tides is due to changes in the mean flow structure and the superposition of the tidal responses to water vapor heating in the troposphere and ozone heating in the stratosphere and lower mesosphere.

  3. Can tides influence volcanic eruptions?

    NASA Astrophysics Data System (ADS)

    Girona, T.; Huber, C.

    2015-12-01

    The possibility that the Moon-Sun gravitational force can affect terrestrial volcanoes and trigger eruptions is a controversial issue that has been proposed since ancient times, and that has been widely debated during the last century. The controversy arises mainly from two reasons. First, the days of initiation of eruptions are not well known for many volcanoes, and thus a robust statistical comparison with tidal cycles cannot be performed for many of them. Second, the stress changes induced by tides in the upper crust are very small (10-3 MPa) compared to the tensile strength of rocks (~ 10-1-10 MPa), and hence the mechanism by which tidal stresses might trigger eruptions is unclear. In this study, we address these issues for persistently degassing volcanoes, as they erupt frequently and thus the initiation time of a significant number of eruptions (>30) is well known in several cases (9). In particular, we find that the occurrence of eruptions within ±2 days from neap tides (first and third quarter moon) is lower than 34% (e.g., 29% for Etna, Italy; 28% for Merapi, Indonesia), which is the value expected if eruptions occur randomly with no external influence. To understand this preference for erupting far away from neap tides, we have developed a new lumped-parameter model that accounts for the deformation of magma reservoirs, a partially open conduit, and a gas layer where bubbles accumulate beneath volcanic craters before being released. We demonstrate that this system reservoir-conduit-gas layer acts as an amplifier of the tidal stresses, such that, when a volcano approaches to a critical state, the gas overpressure beneath the crater can reach up to several MPa more during a spring tide (full and new moon) than during a neap tide. This amplification mechanism can explain why active volcanoes are sensitive to the moon cycles.

  4. The Earth Tides.

    ERIC Educational Resources Information Center

    Levine, Judah

    1982-01-01

    In addition to oceans, the earth is subjected to tidal stresses and undergoes tidal deformations. Discusses origin of tides, tidal stresses, and methods of determining tidal deformations (including gravity, tilt, and strain meters). (JN)

  5. Assessing the importance of internal tide scattering in the deep ocean

    NASA Astrophysics Data System (ADS)

    Haji, Maha; Peacock, Thomas; Carter, Glenn; Johnston, T. M. Shaun

    2014-11-01

    Tides are one of the main sources of energy input to the deep ocean, and the pathways of energy transfer from barotropic tides to turbulent mixing scales via internal tides are not well understood. Large-scale (low-mode) internal tides account for the bulk of energy extracted from barotropic tides and have been observed to propagate over 1000 km from their generation sites. We seek to examine the fate of these large-scale internal tides and the processes by which their energy is transferred, or ``scattered,'' to small-scale (high-mode) internal tides, which dissipate locally and are responsible for internal tide driven mixing. The EXperiment on Internal Tide Scattering (EXITS) field study conducted in 2010-2011 sought to examine the role of topographic scattering at the Line Islands Ridge. The scattering process was examined via data from three moorings equipped with moored profilers, spanning total depths of 3000--5000 m. The results of our field data analysis are rationalized via comparison to data from two- and three-dimensional numerical models and a two-dimensional analytical model based on Green function theory.

  6. Understanding the Global Variability in Thermospheric Nitric Oxide Flux Using Empirical Orthogonal Functions (EOFs)

    NASA Astrophysics Data System (ADS)

    Flynn, Sierra; Knipp, Delores J.; Matsuo, Tomoko; Mlynczak, Martin; Hunt, Linda

    2018-05-01

    We present the first-ever global assessment of thermospheric nitric oxide infrared radiative flux (NOF) variability. NOF (W/m2) from 100- to 250-km altitude is extracted from 13.7 years of data from the TIMED satellite, Sounding of the Atmosphere using Broadband Emission Radiometry (SABER) instrument, and decomposed into four empirical orthogonal functions (EOFs) and their amplitudes. We determine the strongest modes of NOF variability in the data set and develop a compact model of NOF. The first four EOFs account for 83% of the variability in the data. We illustrate the NOF model and discuss the geophysical associations of the EOFs. The first EOF represents 69% of the total variance and correlates strongly with Kp and solar shortwave flux, suggesting that geomagnetic activity and solar weather account for a large portion of NOF variability. EOF 2 shows annual and seasonal variations, possibly due to annual and seasonal thermospheric composition and temperature changes and may represent the chemical breathing mode of NOF. EOF 3 shows annual variations and correlates with solar energetic particle events and X-flares. EOF 3 may represent winter time solar energetic particle event-enhanced diurnal tide effects. EOF 4 suggests a meridional transport mechanism at the predawn and postdusk equator after strong storms. The EOF uncertainty is verified using cross-validation analysis. Quantifying the spatial and temporal variabilities of NOF using eigenmodes will increase the understanding of how upper atmospheric nitric oxide cooling behaves and could increase the accuracy of future space weather and climate models.

  7. Fortnightly Earth Rotation, Ocean Tides, and Mantle Anelasticity

    NASA Technical Reports Server (NTRS)

    Ray, Richard D.; Egbert, Gary D.

    2011-01-01

    Sustained accurate measurements of earth rotation are one of the prime goals of Global Geodetic Observing System (GGOS). We here concentrate on the fortnightly (Mf) tidal component of earth-rotation data to obtain new results concerning anelasticity of the mantle at this period. The study comprises three parts: (1) a new determination of the Mf component of polar motion and length-of-day from a multi-decade time series of space-geodetic data; (2) the use of the polar-motion determination as one constraint in the development of a hydrodynamic ocean model of the Mf tide; and (3) the use of these results to place new constraints on mantle anelasticity. Our model of the Mf ocean tide assimilates more than fourteen years of altimeter data from the Topex/Poseidon and Jason-1 satellites. The polar motion data, plus tide-gauge data and independent altimeter data, give useful additional information, with only the polar motion putting constraints on tidal current velocities. The resulting ocean-tide model, plus the dominant elastic body tide, leaves a small residual in observed length-of-day caused by mantle anelasticity. The inferred effective tidal 0 of the anelastic body tide is 90 and is in line with a omega-alpha frequency dependence with alpha in the range 0.2--0.3.

  8. The double high tide at Port Ellen: Doodson's criterion revisited

    NASA Astrophysics Data System (ADS)

    Byrne, Hannah A. M.; Mattias Green, J. A.; Bowers, David G.

    2017-07-01

    Doodson proposed a minimum criterion to predict the occurrence of double high (or double low) waters when a higher-frequency tidal harmonic is added to the semi-diurnal tide. If the phasing of the harmonic is optimal, the condition for a double high water can be written bn2/a > 1 where b is the amplitude of the higher harmonic, a is the amplitude of the semi-diurnal tide, and n is the ratio of their frequencies. Here we expand this criterion to allow for (i) a phase difference ϕ between the semi-diurnal tide and the harmonic and (ii) the fact that the double high water will disappear in the event that b/a becomes large enough for the higher harmonic to be the dominant component of the tide. This can happen, for example, at places or times where the semi-diurnal tide is very small. The revised parameter is br2/a, where r is a number generally less than n, although equal to n when ϕ = 0. The theory predicts that a double high tide will form when this parameter exceeds 1 and then disappear when it exceeds a value of order n2 and the higher harmonic becomes dominant. We test these predictions against observations at Port Ellen in the Inner Hebrides of Scotland. For most of the data set, the largest harmonic of the semi-diurnal tide is the sixth diurnal component, for which n = 3. The principal lunar and solar semi-diurnal tides are about equal at Port Ellen and so the semi-diurnal tide becomes very small twice a month at neap tides (here defined as the smallest fortnightly tidal range). A double high water forms when br2/a first exceeds a minimum value of about 1.5 as neap tides are approached and then disappears as br2/a then exceeds a second limiting value of about 10 at neap tides in agreement with the revised criterion.

  9. Control of the phytoplankton distribution in the Strait of Gibraltar by wind and fortnightly tides

    NASA Astrophysics Data System (ADS)

    Gómez, F.; Gorsky, G.; García-Górriz, E.; Picheral, M.

    2004-03-01

    CTD-fluorescence-turbidity profiles from two surveys conducted in June and September 1997 were examined in order to evaluate the influence of the predictable fortnightly (spring/neap) tidal cycle and the less predictable wind on the phytoplankton distribution in the Strait of Gibraltar. The injection of the nutrient-rich North Atlantic Water (NACW) in the Atlantic inflowing current is associated with initial phytoplankton blooming conditions (high fluorescence, low turbidity). In September, a thick layer of NACW was recorded in the euphotic zone of the Atlantic side of the Strait, but biological variables showed post-bloom conditions. This is interpreted as the previous development of a phytoplankton bloom favoured by the ascent of NACW into the euphotic zone during the neap tide period. The passage of NACW through the Strait into the Mediterranean Sea was initially hindered by easterly winds and later by the spring tide. The neap tide period favoured the injection and passage of nutrient-rich North Atlantic Water (NACW) into the Atlantic inflowing current, enhanced during the westerly winds regime. During the spring tides, the injection and passage of NACW is hindered, especially when the easterlies blow. The contribution of the NACW to the primary production was estimated as 100-150 kg carbon s -1 (enhanced during the neap tides). The influence of the wind-driven upwelling along the NW Alborán Sea on the northeastern side of the Strait is discussed.

  10. Aerosolized red-tide toxins (brevetoxins) and asthma.

    PubMed

    Fleming, Lora E; Kirkpatrick, Barbara; Backer, Lorraine C; Bean, Judy A; Wanner, Adam; Reich, Andrew; Zaias, Julia; Cheng, Yung Sung; Pierce, Richard; Naar, Jerome; Abraham, William M; Baden, Daniel G

    2007-01-01

    With the increasing incidence of asthma, there is increasing concern over environmental exposures that may trigger asthma exacerbations. Blooms of the marine microalgae, Karenia brevis, cause red tides (or harmful algal blooms) annually throughout the Gulf of Mexico. K brevis produces highly potent natural polyether toxins, called brevetoxins, which are sodium channel blockers, and possibly histamine activators. In experimental animals, brevetoxins cause significant bronchoconstriction. In humans, a significant increase in self-reported respiratory symptoms has been described after recreational and occupational exposures to Florida red-tide aerosols, particularly among individuals with asthma. Before and after 1 h spent on beaches with and without an active K brevis red-tide exposure, 97 persons >or= 12 years of age with physician-diagnosed asthma were evaluated by questionnaire and spirometry. Concomitant environmental monitoring, water and air sampling, and personal monitoring for brevetoxins were performed. Participants were significantly more likely to report respiratory symptoms after K brevis red-tide aerosol exposure than before exposure. Participants demonstrated small, but statistically significant, decreases in FEV(1), midexpiratory phase of forced expiratory flow, and peak expiratory flow after exposure, particularly among those participants regularly using asthma medications. No significant differences were detected when there was no Florida red tide (ie, during nonexposure periods). This study demonstrated objectively measurable adverse changes in lung function from exposure to aerosolized Florida red-tide toxins in asthmatic subjects, particularly among those requiring regular therapy with asthma medications. Future studies will assess these susceptible subpopulations in more depth, as well as the possible long-term effects of these toxins.

  11. Aerosolized Red-Tide Toxins (Brevetoxins) and Asthma

    PubMed Central

    Fleming, Lora E.; Kirkpatrick, Barbara; Backer, Lorraine C.; Bean, Judy A.; Wanner, Adam; Reich, Andrew; Zaias, Julia; Cheng, Yung Sung; Pierce, Richard; Naar, Jerome; Abraham, William M.; Baden, Daniel G.

    2009-01-01

    Background With the increasing incidence of asthma, there is increasing concern over environmental exposures that may trigger asthma exacerbations. Blooms of the marine microalgae, Karenia brevis, cause red tides (or harmful algal blooms) annually throughout the Gulf of Mexico. K brevis produces highly potent natural polyether toxins, called brevetoxins, which are sodium channel blockers, and possibly histamine activators. In experimental animals, brevetoxins cause significant bronchoconstriction. In humans, a significant increase in self-reported respiratory symptoms has been described after recreational and occupational exposures to Florida red-tide aerosols, particularly among individuals with asthma. Methods Before and after 1 h spent on beaches with and without an active K brevis red-tide exposure, 97 persons ≥ 12 years of age with physician-diagnosed asthma were evaluated by questionnaire and spirometry. Concomitant environmental monitoring, water and air sampling, and personal monitoring for brevetoxins were performed. Results Participants were significantly more likely to report respiratory symptoms after K brevis red-tide aerosol exposure than before exposure. Participants demonstrated small, but statistically significant, decreases in FEV1, midexpiratory phase of forced expiratory flow, and peak expiratory flow after exposure, particularly among those participants regularly using asthma medications. No significant differences were detected when there was no Florida red tide (ie, during nonexposure periods). Conclusions This study demonstrated objectively measurable adverse changes in lung function from exposure to aerosolized Florida red-tide toxins in asthmatic subjects, particularly among those requiring regular therapy with asthma medications. Future studies will assess these susceptible subpopulations in more depth, as well as the possible long-term effects of these toxins. PMID:17218574

  12. Squeezing of particle distributions by expanding magnetic turbulence and space weather variability

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Ruffolo, D.; Seripienlert, A.; Tooprakai, P.

    Among the space weather effects due to gradual solar storms, greatly enhanced high-energy ion fluxes contribute to radiation damage to satellites, spacecraft, and astronauts and dominate the hazards to air travelers, which motivates examination of the transport of high-energy solar ions to Earth's orbit. Ions of low kinetic energy (up to ∼2 MeV nucleon{sup –1}) from impulsive solar events exhibit abrupt changes due to filamentation of the magnetic connection from the Sun, indicating that anisotropic, field-aligned magnetic flux tubelike structures persist to Earth's orbit. By employing a corresponding spherical two-component model of Alfvénic (slab) and two-dimensional magnetic fluctuations to tracemore » simulated trajectories in the solar wind, we show that the distribution of high-energy (E ≥ 1 GeV) protons from gradual solar events is squeezed toward magnetic flux structures with a specific polarity because of the conical shape of the flux structures. Conical flux structures and the squeezing of energetic particle distributions should occur in any astrophysical wind or jet with expanding, magnetized, turbulent plasma. This transport phenomenon contributes to event-to-event variability in ground level enhancements of GeV-range ions from solar storms, presenting a fundamental uncertainty in space weather prediction.« less

  13. Non-stationary internal tides observed with satellite altimetry

    NASA Astrophysics Data System (ADS)

    Ray, R. D.; Zaron, E. D.

    2011-09-01

    Temporal variability of the internal tide is inferred from a 17-year combined record of Topex/Poseidon and Jason satellite altimeters. A global sampling of along-track sea-surface height wavenumber spectra finds that non-stationary variance is generally 25% or less of the average variance at wavenumbers characteristic of mode-1 tidal internal waves. With some exceptions the non-stationary variance does not exceed 0.25 cm2. The mode-2 signal, where detectable, contains a larger fraction of non-stationary variance, typically 50% or more. Temporal subsetting of the data reveals interannual variability barely significant compared with tidal estimation error from 3-year records. Comparison of summer vs. winter conditions shows only one region of noteworthy seasonal changes, the northern South China Sea. Implications for the anticipated SWOT altimeter mission are briefly discussed.

  14. Non-Stationary Internal Tides Observed with Satellite Altimetry

    NASA Technical Reports Server (NTRS)

    Ray, Richard D.; Zaron, E. D.

    2011-01-01

    Temporal variability of the internal tide is inferred from a 17-year combined record of Topex/Poseidon and Jason satellite altimeters. A global sampling of along-track sea-surface height wavenumber spectra finds that non-stationary variance is generally 25% or less of the average variance at wavenumbers characteristic of mode-l tidal internal waves. With some exceptions the non-stationary variance does not exceed 0.25 sq cm. The mode-2 signal, where detectable, contains a larger fraction of non-stationary variance, typically 50% or more. Temporal subsetting of the data reveals interannual variability barely significant compared with tidal estimation error from 3-year records. Comparison of summer vs. winter conditions shows only one region of noteworthy seasonal changes, the northern South China Sea. Implications for the anticipated SWOT altimeter mission are briefly discussed.

  15. In Brief: Red tide Web site

    NASA Astrophysics Data System (ADS)

    Showstack, Randy; Kumar, Mohi

    2008-06-01

    The U.S. National Oceanic and Atmospheric Administration has established the NOAA New England Red Tide Information Center to help people understand the significant red tides that are predicted to form there later this spring. The site (http://www.oceanservice.noaa.gov/redtide) will provide a summary of the current red tide situation and its potential harmful impacts on humans and animals and will serve as a central repository of information. The site also will have direct links to news releases, changes to relevant federal fishing regulations, links to closures of shellfish waters, and links to state agency Web sites with localized information. In addition, the site will have information about NOAA's scientific response effort as well as information from several other sources including NOAA's major response partner, the Woods Hole Oceanographic Institution (WHOI). On 24 April, WHOI scientists, using forecast models developed with NOAA funding support, predicted ``that excess winter precipitation has set the stage for a harmful algal bloom similar to the historic red tide of 2005.'' That bloom shut down shellfish beds from the Bay of Fundy to Martha's Vineyard for several months.

  16. Nonlinearity in rock - Evidence from earth tides

    NASA Technical Reports Server (NTRS)

    Agnew, D. C.

    1981-01-01

    The earth is sinusoidally stressed by tidal forces; if the stress-strain relation for rock is nonlinear, energy should appear in an earth tide record at frequencies which are multiples of those of the larger tidal lines. An examination of the signals to be expected for different nonlinear deformation laws shows that for a nonlinear response without dissipation, the largest anomalous signal should occur at twice the forcing frequency, whereas for nonlinear laws involving dissipation (cusped hysteresis loops) the anomalous signal will be greatest at three times this frequency. The size of the signal in the dissipative case depends on the amount by which dissipation affects the particular response being measured. For measurements of strain tides this depends on whether dissipation is assumed to be present throughout the earth or localized around the point of measurement. An analysis of 5.7 years of strain tide records from Pinon Flat, California, shows a small signal at twice the frequency of the largest (M2) tide.

  17. Global ocean tide models on the eve of Topex/Poseidon

    NASA Technical Reports Server (NTRS)

    Ray, Richard D.

    1993-01-01

    Some existing global ocean tide models that can provide tide corrections to Topex/Poseidon altimeter data are described. Emphasis is given to the Schwiderski and Cartwright-Ray models, as these are the most comprehensive, highest resolution models, but other models that will soon appear are mentioned. Differences between models for M2 often exceed 10 cm over vast stretches of the ocean. Comparisons to 80 selected pelagic and island gauge measurements indicate the Schwiderski model is more accurate for the major solar tides, Cartwright-Ray for the major lunar tides. The adequacy of available tide models for studying basin-scale motions is probably marginal at best.

  18. Spatial variability of polycyclic aromatic hydrocarbon load of urban wet weather pollution in combined sewers.

    PubMed

    Gasperi, J; Moilleron, R; Chebbo, G

    2006-01-01

    In Paris, the OPUR research programme created an experimental on-site observatory of urban pollutant loads in combined sewer systems in order to characterise the dry and wet weather flows at different spatial scales. This article presents the first results on the spatial variability of the polycyclic aromatic hydrocarbon (PAH) load during wet weather flow (WWF). At the scale of a rain event, investigations revealed that (i) PAH concentrations were relatively homogenous whatever the spatial scale and were greater than those of the dry weather flow (DWF), (ii) PAH distributions between dissolved and particulate phases were constant, and (iii) PAH fingerprints exhibited a similar pattern for all catchments. Moreover, an evaluation of the contribution of DWF, runoff and erosion of sewer deposits to WWF load was established. According to the hypothesis on the runoff concentration, the contributions were evaluated at 14, 8 and 78%, respectively, at the scale of the Marais catchment. For all the catchments, the runoff contribution was found quite constant and evaluated at approximately 10%. The DWF contribution seems to increase with the catchment area, contrary to the sewer erosion contribution, which seems to decrease. However, this latter still remains an important source of pollution. These first trends should be confirmed and completed by more investigations of rain events.

  19. Squeezing of Particle Distributions by Expanding Magnetic Turbulence and Space Weather Variability

    NASA Astrophysics Data System (ADS)

    Ruffolo, D. J.; Tooprakai, P.; Seripienlert, A.; Chuychai, P.; Matthaeus, W. H.

    2014-12-01

    Among the space weather effects due to gradual solar storms, greatly enhanced high-energy ion fluxes can cause radiation damage to satellites, spacecraft, and astronauts, which motivates examination of the transport of high-energy solar ions to Earth orbit. Ions of low kinetic energy (up to ˜2sim 2 MeV/nucleon) from impulsive solar events exhibit abrupt changes due to filamentation of magnetic connection from the Sun, indicating that anisotropic, field-aligned magnetic flux tube-like structures persist to Earth orbit. By employing a corresponding spherical two-component model of Alfv'enic (slab) and 2D magnetic fluctuations to trace simulated trajectories in the solar wind, we show that the distribution of high-energy (E≥1Egeq1 GeV) protons from gradual solar events is squeezed toward magnetic flux structures with a specific polarity due to the conical shape of the flux structures, which results from the expanding flow of the solar wind. It is difficult to observationally determine what polarity of flux structure the Earth is in at a given time, so this transport phenomenon contributes to event-to-event variability in ground level enhancements of GeV-range ions from solar storms, presenting a fundamental uncertainty in space weather prediction. Partially supported by the Thailand Research Fund, a Postdoctoral Fellowship from the Thailand Center of Excellence in Physics, a Research Fellowship from the Faculty of Science, Mahidol University, the U.S. NSF (AGS-1063439 and SHINE AGS-1156094), NASA (Heliophysics Theory NNX08AI47G & NNX11AJ44G), and the Solar Probe Plus/ISIS project. KEYWORDS: [7807] SPACE PLASMA PHYSICS / Charged particle motion and acceleration, [7863] SPACE PLASMA PHYSICS / Turbulence, [2118] INTERPLANETARY PHYSICS / Energetic particles, solar, [7984] SPACE WEATHER / Space radiation environment

  20. Organizational Analysis of the TIDES Project and the STAR-TIDES Network Using the 7-S Framework

    DTIC Science & Technology

    2013-04-01

    data, provided some useful rec- ommendations.8 Since that time, TIDES has continued to grow and change. The present study was undertaken to update the...information across platforms and within the secure NDU network. For ex- ample, many contacts made by the Director are preserved within his Blackberry ...the active participation of STAR-TIDES network members, and to grow the network. 5. Skills Skills refers to the talents and abilities of the

  1. Orthogonal stack of global tide gauge sea level data

    NASA Technical Reports Server (NTRS)

    Trupin, A.; Wahr, J.

    1990-01-01

    Yearly and monthly tide gauge sea level data from around the globe are fitted to numerically generated equilibrium tidal data to search for the 18.6 year lunar tide and 14 month pole tide. Both tides are clearly evident in the results, and their amplitudes and phases are found to be consistent with a global equilibrium response. Global, monthly sea level data from outside the Baltic sea and Gulf of Bothnia are fitted to global atmospheric pressure data to study the response of the ocean to pressure fluctuations. The response is found to be inverted barometer at periods greater than two months. Global averages of tide gauge data, after correcting for the effects of post glacial rebound on individual station records, reveal an increase in sea level over the last 80 years of between 1.1 mm/yr and 1.9 mm/yr.

  2. Effect of Weather Variability on Seasonal Influenza Among Different Age Groups in Queensland, Australia: A Bayesian Spatiotemporal Analysis.

    PubMed

    Huang, Xiaodong; Mengersen, Kerrie; Milinovich, Gabriel; Hu, Wenbiao

    2017-06-01

    The effects of weather variability on seasonal influenza among different age groups remain unclear. The comparative study aims to explore the differences in the associations between weather variability and seasonal influenza, and growth rates of seasonal influenza epidemics among different age groups in Queensland, Australia. Three Bayesian spatiotemporal conditional autoregressive models were fitted at the postal area level to quantify the relationships between seasonal influenza and monthly minimum temperature (MIT), monthly vapor pressure, school calendar pattern, and Index of Relative Socio-Economic Advantage and Disadvantage for 3 age groups (<15, 15-64, and ≥65 years). The results showed that the expected decrease in monthly influenza cases was 19.3% (95% credible interval [CI], 14.7%-23.4%), 16.3% (95% CI, 13.6%-19.0%), and 8.5% (95% CI, 1.5%-15.0%) for a 1°C increase in monthly MIT at <15, 15-64, and ≥65 years of age, respectively, while the average increase in the monthly influenza cases was 14.6% (95% CI, 9.0%-21.0%), 12.1% (95% CI, 8.8%-16.1%), and 9.2% (95% CI, 1.4%-16.9%) for a 1-hPa increase in vapor pressure. Weather variability appears to be more influential on seasonal influenza transmission in younger (0-14) age groups. The growth rates of influenza at postal area level were relatively small for older (≥65) age groups in Queensland, Australia. © The Author 2017. Published by Oxford University Press for the Infectious Diseases Society of America. All rights reserved. For permissions, e-mail: journals.permissions@oup.com.

  3. The IERS Special Bureau for Tides

    NASA Technical Reports Server (NTRS)

    Ray, Richard D.; Chao, B. F.; Desai, S. D.

    2002-01-01

    The Global Geophysical Fluids Center of the International Earth Rotation Service (IERS) comprises 8 special bureaus, one of which is the Special Bureau for Tides. Its purpose is to facilitate studies related to tidal effects in earth rotation. To that end it collects various relevant datasets and distributes them, primarily through its website at bowie.gsfc.nasa.gov/ggfc/tides. Example datasets include tabulations of tidal variations in angular momentum and in earth rotation as estimated from numerical ocean tide models and from meteorological reanalysis products. The web site also features an interactive tidal prediction "machine" which generates tidal predictions (e.g., of UT1) from lists of harmonic constants. The Special Bureau relies on the tidal and earth-rotation communities to build and enlarge its datasets; further contributions from this community are most welcome.

  4. Gastrointestinal Emergency Room Admissions and Florida Red Tide Blooms.

    PubMed

    Kirkpatrick, Barbara; Bean, Judy A; Fleming, Lora E; Kirkpatrick, Gary; Grief, Lynne; Nierenberg, Kate; Reich, Andrew; Watkins, Sharon; Naar, Jerome

    2010-01-01

    Human exposure to brevetoxins during Florida red tide blooms formed by Karenia brevis has been documented to cause acute gastrointestinal, neurologic, and respiratory health effects.. Traditionally, the routes of brevetoxin exposure have been through the consumption of contaminated bivalve shellfish and the inhalation of contaminated aerosols. However, recent studies using more sensitive methods have demonstrated the presence of brevetoxins in many components of the aquatic food web which may indicate potential alternative routes for human exposure.This study examined whether the presence of a Florida red tide bloom affected the rates of admission for a gastrointestinal diagnosis to a hospital emergency room in Sarasota, FL. The rates of gastrointestinal diagnoses admissions were compared for a 3-month time period in 2001 when Florida red tide bloom was present onshore to the same 3-month period in 2002 when no Florida red tide bloom occurred. A significant 40% increase in the total number of gastrointestinal emergency room admissions for the Florida red tide bloom period was found compared to the non red tide period.These results suggest that the healthcare community may experience a significant and unrecognized impact from patients needing emergency medical care for gastrointestinal illnesses during Florida red tide blooms. Thus, additional studies characterizing the potential sources of exposure to the toxins, as well as the dose/effect relationship of brevetoxin exposure, should be undertaken.

  5. Gastrointestinal Emergency Room Admissions and Florida Red Tide Blooms

    PubMed Central

    Kirkpatrick, Barbara; Bean, Judy A; Fleming, Lora E; Kirkpatrick, Gary; Grief, Lynne; Nierenberg, Kate; Reich, Andrew; Watkins, Sharon; Naar, Jerome

    2009-01-01

    Human exposure to brevetoxins during Florida red tide blooms formed by Karenia brevis has been documented to cause acute gastrointestinal, neurologic, and respiratory health effects.. Traditionally, the routes of brevetoxin exposure have been through the consumption of contaminated bivalve shellfish and the inhalation of contaminated aerosols. However, recent studies using more sensitive methods have demonstrated the presence of brevetoxins in many components of the aquatic food web which may indicate potential alternative routes for human exposure. This study examined whether the presence of a Florida red tide bloom affected the rates of admission for a gastrointestinal diagnosis to a hospital emergency room in Sarasota, FL. The rates of gastrointestinal diagnoses admissions were compared for a 3-month time period in 2001 when Florida red tide bloom was present onshore to the same 3-month period in 2002 when no Florida red tide bloom occurred. A significant 40% increase in the total number of gastrointestinal emergency room admissions for the Florida red tide bloom period was found compared to the non red tide period. These results suggest that the healthcare community may experience a significant and unrecognized impact from patients needing emergency medical care for gastrointestinal illnesses during Florida red tide blooms. Thus, additional studies characterizing the potential sources of exposure to the toxins, as well as the dose/effect relationship of brevetoxin exposure, should be undertaken. PMID:20161425

  6. The Global Mode-1 S2 Internal Tide

    NASA Astrophysics Data System (ADS)

    Zhao, Zhongxiang

    2017-11-01

    The global mode-1 S2 internal tide is observed using sea surface height (SSH) measurements from four satellite altimeters: TOPEX/Poseidon, Jason-1, Jason-2, and Geosat Follow-On. Plane wave analysis is employed to extract three mode-1 S2 internal tidal waves in any given 250 km by 250 km window, which are temporally coherent over a 20 year period from 1992 to 2012. Depth-integrated energy and flux of the S2 internal tide are calculated from the SSH amplitude and a conversion function built from climatological hydrographic profiles in the World Ocean Atlas 2013. The results show that the S2 and M2 internal tides have similar spatial patterns. Both S2 and M2 internal tides originate at major topographic features and propagate over long distances. The S2 internal tidal beams are generally shorter, likely because the relatively weaker S2 internal tide is easily overwhelmed by nontidal noise. The northbound S2 and M2 internal tides from the Hawaiian Ridge are observed to travel over 3500 km across the Northeast Pacific. The globally integrated energy of the mode-1 S2 internal tide is 7.8 PJ (1 PJ = 1015 J), about 20% that of M2 (36.4 PJ). The histogram of S2 to M2 SSH ratios peaks at 0.4, consistent with the square root of their energy ratio. In terms of SSH, S2 is greater than M2 in ≈10% of the global ocean and ≥50% of M2 in about half of the global ocean.

  7. Designing low-carbon power systems for Great Britain in 2050 that are robust to the spatiotemporal and inter-annual variability of weather

    NASA Astrophysics Data System (ADS)

    Zeyringer, Marianne; Price, James; Fais, Birgit; Li, Pei-Hao; Sharp, Ed

    2018-05-01

    The design of cost-effective power systems with high shares of variable renewable energy (VRE) technologies requires a modelling approach that simultaneously represents the whole energy system combined with the spatiotemporal and inter-annual variability of VRE. Here, we soft-link a long-term energy system model, which explores new energy system configurations from years to decades, with a high spatial and temporal resolution power system model that captures VRE variability from hours to years. Applying this methodology to Great Britain for 2050, we find that VRE-focused power system design is highly sensitive to the inter-annual variability of weather and that planning based on a single year can lead to operational inadequacy and failure to meet long-term decarbonization objectives. However, some insights do emerge that are relatively stable to weather-year. Reinforcement of the transmission system consistently leads to a decrease in system costs while electricity storage and flexible generation, needed to integrate VRE into the system, are generally deployed close to demand centres.

  8. Untangling the roles of wind, run-off and tides in Prince William Sound

    NASA Astrophysics Data System (ADS)

    Colas, François; Wang, Xiaochun; Capet, Xavier; Chao, Yi; McWilliams, James C.

    2013-07-01

    Prince William Sound (PWS) oceanic circulation is driven by a combination of local wind, large run-off and strong tides. Using a regional oceanic model of the Gulf of Alaska, adequately resolving the mean circulation and mesoscale eddies, we configure a series of three nested domains. The inner domain zooms in on Prince William Sound with a 1-km horizontal grid resolution. We analyze a set of four experiments with different combinations of run-off, wind and tides to demonstrate the relative influence of these forcing on the central Sound mean circulation cell and its seasonal variability. The mean circulation in the central PWS region is generally characterized by a cyclonic cell. When forced only by the wind, the circulation is cyclonic in winter and fall and strongly anticyclonic in summer. The addition of freshwater run-off greatly enhances the eddy kinetic energy in PWS partly through near-surface baroclinic instabilities. This leads to a much more intermittent circulation in the central Sound, with the presence of intense small-scale turbulence and a disappearance of the summer wind-forced anticyclonic cell. The addition of tides reduces the turbulence intensity (relatively to the experiment with run-off only), particularly in the central Sound. The generation of turbulent motions by baroclinic processes is lowered by tidal mixing and by modification of the exchange at Hinchinbrook Entrance. Tides have an overall stabilizing effect on the central Sound circulation. Tidal rectification currents help maintain a mean cyclonic circulation throughout the year.

  9. The lunar semidiurnal tide at the polar summer mesopause observed by SOFIE

    NASA Astrophysics Data System (ADS)

    Hoffmann, C. G.; von Savigny, C.; Hervig, M. E.; Oberbremer, E.

    2018-01-01

    The polar summer mesopause, particularly the presence of noctilucent clouds (NLCs), exhibits pronounced temporal variability. Parts of this variability are thought to be caused by lunar tidal influences. We extract the semidiurnal lunar tide in various NLC related parameters by applying the superposed epoch analysis method to the dataset of the SOFIE satellite instrument. Analyzing the NLC seasons from 2007 to 2015 in the northern and southern hemisphere we, first, confirm the influence of the lunar tide on ice water content (IWC) and temperature. For both parameters the lunar influence had already recently been demonstrated in satellite measurements. Second, we apply the analysis to the variety of parameters observed by SOFIE including trace gases (H2O , O3 , CH4 , and NO), NLC properties (e.g., NLC altitudes and ice mass density), microphysical properties (e.g., particle concentration and mean radius), and mesopause properties. In all of these parameters we find signatures of the semidiurnal lunar tide, which is the first demonstration of this effect for all of these parameters. We quantify the lunar influence in terms of amplitudes and phases. Whereas the focus of the present study is providing observational evidence for the existence of lunar tidal signatures in various parameters, we do not aim at investigating the underlying mechanisms in detail, which is only possible with the utilization of comprehensive modeling approaches. Nevertheless, we briefly discuss the relations to known processes of the NLC evolution where appropriate, e.g., the relevance of the freeze-drying effect for the signature in H2O and the relation of IWC and NLC altitudes.

  10. Day-to-day ionospheric variability due to lower atmosphere perturbations

    NASA Astrophysics Data System (ADS)

    Liu, H.; Yudin, V. A.; Roble, R. G.

    2013-12-01

    Ionospheric day-to-day variability is a ubiquitous feature, even in the absence of appreciable geomagnetic activities. Although meteorological perturbations have been recognized as an important source of the variability, it is not well represented in previous modeling studies, and the mechanism is not well understood. This study demonstrates that TIME-GCM (Thermosphere-Ionosphere-Mesosphere-Electrodynamics General Circulation Model) constrained in the stratosphere and mesosphere by the hourly Whole Atmosphere Community Climate Model (WACCM) simulations is capable of reproducing observed features of day-to-day variability in the thermosphere-ionosphere. Realistic weather patterns in the lower atmosphere in WACCM was specified by Modern Era Retrospective reanalysis for Research and Application (MERRA). The day-to-day variations in mean zonal wind, migrating and non-migrating tides in the thermosphere, vertical and zonal ExB drifts, and ionosphere F2 layer peak electron density (NmF2) are examined. The standard deviations of the drifts and NmF2 display local time and longitudinal dependence that compare favorably with observations. Their magnitudes are 50% or more of those from observations. The day-to-day thermosphere and ionosphere variability in the model is primarily caused by the perturbations originated in lower atmosphere, since the model simulation is under constant solar minimum and low geomagnetic conditions.

  11. Improved Estimates of Temporally Coherent Internal Tides and Energy Fluxes from Satellite Altimetry

    NASA Technical Reports Server (NTRS)

    Ray, Richard D.; Chao, Benjamin F. (Technical Monitor)

    2002-01-01

    Satellite altimetry has opened a surprising new avenue to observing internal tides in the open ocean. The tidal surface signatures are very small, a few cm at most, but in many areas they are robust, owing to averaging over many years. By employing a simplified two dimensional wave fitting to the surface elevations in combination with climatological hydrography to define the relation between the surface height and the current and pressure at depth, we may obtain rough estimates of internal tide energy fluxes. Initial results near Hawaii with Topex/Poseidon (T/P) data show good agreement with detailed 3D (three dimensional) numerical models, but the altimeter picture is somewhat blurred owing to the widely spaced T/P tracks. The resolution may be enhanced somewhat by using data from the ERS-1 (ESA (European Space Agency) Remote Sensing) and ERS-2 satellite altimeters. The ERS satellite tracks are much more closely spaced (0.72 deg longitude vs. 2.83 deg for T/P), but the tidal estimates are less accurate than those for T/P. All altimeter estimates are also severely affected by noise in regions of high mesoscale variability, and we have obtained some success in reducing this contamination by employing a prior correction for mesoscale variability based on ten day detailed sea surface height maps developed by Le Traon and colleagues. These improvements allow us to more clearly define the internal tide surface field and the corresponding energy fluxes. Results from throughout the global ocean will be presented.

  12. Mesospheric Non-Migrating Tides Generated With Planetary Waves. 1; Characteristics

    NASA Technical Reports Server (NTRS)

    Mayr, H. G.; Mengel, J. G.; Talaat, E. L.; Porter, H. S.; Chan, K. L.

    2003-01-01

    We discuss results from a modeling study with our Numerical Spectral Model (NSM) that specifically deals with the non-migrating tides generated in the mesosphere. The NSM extends from the ground to the thermosphere, incorporates Hines' Doppler Spread Parameterization for small-scale gravity waves (GWs), and it describes the major dynamical features of the atmosphere including the wave driven equatorial oscillations (QBO and SAO), and the seasonal variations of tides and planetary waves. Accounting solely for the excitation sources of the solar migrating tides, the NSM generates through dynamical interactions also non-migrating tides in the mesosphere that are comparable in magnitude to those observed. Large non-migrating tides are produced in the diurnal and semi-diurnal oscillations for the zonal mean (m = 0) and in the semidiurnal oscillation for m = 1. In general, significant eastward and westward propagating tides are generated for all the zonal wave numbers m = 1 to 4. To identify the cause, the NSM is run without the solar heating for the zonal mean (m = 0), and the amplitudes of the resulting non-migrating tides are then negligibly small. In this case, the planetary waves are artificially suppressed, which are generated in the NSM through instabilities. This leads to the conclusion that the non-migrating tides are generated through non-linear interactions between planetary waves and migrating tides, as Forbes et al. and Talaat and Liberman had proposed. In an accompanying paper, we present results from numerical experiments, which indicate that gravity wave filtering contributes significantly to produce the non-linear coupling that is involved.

  13. Internal Tide Generation by Steep Topography

    DTIC Science & Technology

    2007-09-01

    acting on the barotropic tide ( Foda and Hill 1998) was incomplete. Kunze will put this work in the context of recent internal tide research and...Topographically generated internal waves in the open ocean. J. Geophys. Res., 80, 320-327. Foda , M.A., and D.F. Hill, 1998: Nonlinear energy...Bispectral analysis of energy transfer within the two-dimensional ocean internal wave field. . Phys. Oceanogr., 35, 2104-2109. Garrett, C., and E

  14. Refine of Regional Ocean Tide Model Using GPS Data

    NASA Astrophysics Data System (ADS)

    Wang, F.; Zhang, P.; Sun, Z.; Jiang, Z.; Zhang, Q.

    2018-04-01

    Due to lack of regional data constraints, all global ocean tide models are not accuracy enough in offshore areas around China, also the displacements predicted by different models are not consistency. The ocean tide loading effects have become a major source of error in the high precision GPS positioning. It is important for high precision GPS applications to build an appropriate regional ocean tide model. We first process the four offshore GPS tracking station's observation data which located in Guangdong province of China by using PPP aproach to get the time series. Then use the spectral inversion method to acquire eigenvalues of the Ocean Tidal Loading. We get the estimated value of not only 12hour period tide wave (M2, S2, N2, K2) but also 24hour period tide wave (O1, K1, P1, Q1) which has not been got in presious studies. The contrast test shows that GPS estimation value of M2, K1 is consistent with the result of five famous glocal ocean load tide models, but S2, N2, K2, O1, P1, Q1 is obviously larger.

  15. Differences between mean tide level and mean sea level

    NASA Astrophysics Data System (ADS)

    Woodworth, P. L.

    2017-01-01

    This paper discusses the differences between mean tide level (MTL) and mean sea level (MSL) as demonstrated using information from a global tide gauge data set. The roles of the two main contributors to differences between MTL and MSL (the M4 harmonic of the M2 semidiurnal tide, and the combination of the diurnal tides K1 and O1) are described, with a particular focus on the spatial scales of variation in MTL-MSL due to each contributor. Findings from the tide gauge data set are contrasted with those from a state-of-the-art global tide model. The study is of interest within tidal science, but also has practical importance regarding the type of mean level used to define land survey datums. In addition, an appreciation of MTL-MSL difference is important in the use of the historical sea level data used in climate change research, with implications for some of the data stored in international databanks. Particular studies are made of how MTL and MSL might differ through the year, and if MTL is measured in daylight hours only, as has been the practice of some national geodetic agencies on occasions in the past.

  16. Simulation and video animation of canal flushing created by a tide gate

    USGS Publications Warehouse

    Schoellhamer, David H.

    1988-01-01

    A tide-gate algorithm was added to a one-dimensional unsteady flow model that was calibrated, verified, and used to determine the locations of as many as five tide gates that would maximize flushing in two canal systems. Results from the flow model were used to run a branched Lagrangian transport model to simulate the flushing of a conservative constituent from the canal systems both with and without tide gates. A tide gate produces a part-time riverine flow through the canal system that improves flushing along the flow path created by the tide gate. Flushing with no tide gates and with a single optimally located tide gate are shown with a video animation.

  17. Lunar tidal acceleration obtained from satellite-derived ocean tide parameters

    NASA Technical Reports Server (NTRS)

    Goad, C. C.; Douglas, B. C.

    1978-01-01

    One hundred sets of mean elements of GEOS-3 computed at 2-day intervals yielded observation equations for the M sub 2 ocean tide from the long periodic variations of the inclination and node of the orbit. The 2nd degree Love number was given the value k sub 2 = 0.30 and the solid tide phase angle was taken to be zero. Combining obtained equations with results for the satellite 1967-92A gives the M sub 2 ocean tide parameter values. Under the same assumption of zero solid tide phase lag, the lunar tidal acceleration was found mostly due to the C sub 22 term in the expansion of the M sub 2 tide with additional small contributions from the 0 sub 1 and N sub 2 tides. Using Lambeck's (1975) estimates for the latter, the obtained acceleration in lunar longitudal in excellent agreement with the most recent determinations from ancient and modern astronomical data.

  18. Tides at the east coast of Lanzarote Island

    NASA Astrophysics Data System (ADS)

    Benavent, M.; Arnoso, J.; Vélez, E. J.

    2012-04-01

    The main goal of this work is the study of the ocean tides at the east coast of Lanzarote (Canary Islands). We have analyzed time series of tide gauge and bottom pressure observations available in the region and we have made a further comparative validation with recent global and local ocean tide models. Lanzarote island shows singular features, with regard its volcanic structure and geomorphological properties and, also, concerning the characteristics of the ocean tides in the surrounding waters. For this reason, this region experiences a great interest in Geodesy and Geodynamics. Particularly, an accurate modelization of the ocean tides is of great importance to correct with high accuracy the effect of the ocean over the multiple geodetic measurements that are being carried out in the Geodynamic Laboratory of Lanzarote, LGL (Vieira et al., 1991; 2006). Furthermore, the analysis of tide gauge and bottom pressure records in this area is of great importance to investigate sea level variations, to evaluate and quantify the causes of these changes and the possible correlation with vertical movements of the Earth's crust. The time series of sea level and bottom pressure data considered in this work are obtained at two different locations of the island and, in each of them, using several sensors at different periods of time. First location is Jameos del Agua (JA) station, which belongs to the LGL. This station is placed in the open ocean, 200 meters distant from the northeastern coast of the island and at 8 meters depth. The observations have been carried out using 3 bottom pressure sensors (Aanderaa WLR7, SAIV TD301A and Aqualogger 210PT) at different periods of time (spanning a total of six years). Second location is Arrecife (AR) station, which is 23 km south of JA station. In this case, the sea level data come from a float tide gauge belonging to the Instituto Español de Oceanografía, installed at the beginning of the loading bay, and a radar tide gauge from the

  19. Parametric vs. non-parametric daily weather generator: validation and comparison

    NASA Astrophysics Data System (ADS)

    Dubrovsky, Martin

    2016-04-01

    As the climate models (GCMs and RCMs) fail to satisfactorily reproduce the real-world surface weather regime, various statistical methods are applied to downscale GCM/RCM outputs into site-specific weather series. The stochastic weather generators are among the most favourite downscaling methods capable to produce realistic (observed like) meteorological inputs for agrological, hydrological and other impact models used in assessing sensitivity of various ecosystems to climate change/variability. To name their advantages, the generators may (i) produce arbitrarily long multi-variate synthetic weather series representing both present and changed climates (in the latter case, the generators are commonly modified by GCM/RCM-based climate change scenarios), (ii) be run in various time steps and for multiple weather variables (the generators reproduce the correlations among variables), (iii) be interpolated (and run also for sites where no weather data are available to calibrate the generator). This contribution will compare two stochastic daily weather generators in terms of their ability to reproduce various features of the daily weather series. M&Rfi is a parametric generator: Markov chain model is used to model precipitation occurrence, precipitation amount is modelled by the Gamma distribution, and the 1st order autoregressive model is used to generate non-precipitation surface weather variables. The non-parametric GoMeZ generator is based on the nearest neighbours resampling technique making no assumption on the distribution of the variables being generated. Various settings of both weather generators will be assumed in the present validation tests. The generators will be validated in terms of (a) extreme temperature and precipitation characteristics (annual and 30 years extremes and maxima of duration of hot/cold/dry/wet spells); (b) selected validation statistics developed within the frame of VALUE project. The tests will be based on observational weather series

  20. Some dinophycean red tide plankton species generate a superoxide scavenging substance.

    PubMed

    Sato, Emiko; Niwano, Yoshimi; Matsuyama, Yukihiko; Kim, Daekyung; Nakashima, Takuji; Oda, Tatsuya; Kohno, Masahiro

    2007-03-01

    Recent studies indicate that some raphidophycean red tide flagellates produce substances able to scavenge superoxide, whereas there have been no reports on superoxide scavenger production by dinophycean red tide flagellates. In this study, we examined the superoxide-scavenging activity of aqueous extracts from dinophycean red tide flagellates, Gymnodinium spp., Scrippsiella trochoidea, and Karenia sp., by a luminol analog L-012-dependent chemiluminescence (CL) method and an electron spin resonance (ESR)-spin trapping method, and compared the activity to that of raphidophycean red tide flagellates, Chattonella spp., Heterosigma akashiwo, and Fibrocapsa japonica. In the experiment applying the L-012-dependent CL method, only the aqueous extracts from raphidophycean red tide flagellates showed superoxide-scavenging activity. On the other hand, applying the ESR-spin trapping method, we found that the aqueous extracts from dinophycean red tide flagellates also showed superoxide-scavenging activity. This is the first report on the production of a superoxide-scavenger by dinophycean red tide flagellates.

  1. Tide-surge Interaction Intensified by the Taiwan Strait

    NASA Astrophysics Data System (ADS)

    Zhang, Wen-Zhou; Shi, Fengyan; Hong, Hua-Sheng; Shang, Shao-Ping; Kirby, James T.

    2010-06-01

    The Taiwan Strait is a long and wide shelf-channel where the hydrodynamics is extremely complex, being characterized by strong tides, and where storm surges frequently occur during the typhoon season. Obvious oscillations due to tide-surge interaction were observed by tide gauges along the northern Fujian coast, the west bank of the Taiwan Strait, during Typhoon Dan (1999). Numerical experiments indicate that nonlinear bottom friction (described by the quadratic formula) is a major factor to predict these oscillations while the nonlinear advective terms and the shallow water effect have little contribution. It is found that the tide-surge interaction in the northern portion of the Taiwan Strait is intensified by the strait. Simulations based on simplified topographies with and without the island of Taiwan show that, in the presence of the island, the channel effect strengthens tidal currents and tends to align the major axes of tidal ellipses along the channel direction. Storm-induced currents are also strengthened by the channel. The pattern of strong tidal currents and storm-induced currents along the channel direction enhances tide-surge interaction via the nonlinear bottom friction, resulting in the obvious oscillations along the northern Fujian coast.

  2. Ocean tide models for satellite geodesy and Earth rotation

    NASA Technical Reports Server (NTRS)

    Dickman, Steven R.

    1991-01-01

    A theory is presented which predicts tides in turbulent, self-gravitating, and loading oceans possessing linearized bottom friction, realistic bathymetry, and continents (at coastal boundaries no-flow conditions are imposed). The theory is phrased in terms of spherical harmonics, which allows the tide equations to be reduced to linear matrix equations. This approach also allows an ocean-wide mass conservation constraint to be applied. Solutions were obtained for 32 long and short period luni-solar tidal constituents (and the pole tide), including the tidal velocities in addition to the tide height. Calibrating the intensity of bottom friction produces reasonable phase lags for all constituents; however, tidal amplitudes compare well with those from observation and other theories only for long-period constituents. In the most recent stage of grant research, traditional theory (Liouville equations) for determining the effects of angular momentum exchange on Earth's rotation were extended to encompass high-frequency excitations (such as short-period tides).

  3. [Study of red tide spectral characteristics and its mechanism].

    PubMed

    Cui, Ting-Wei; Zhang, Jie; Ma, Yi; Sun, Ling

    2006-05-01

    In situ spectral data of different red tide, whose dominant species are leptocylindrus danicus, chattonella marina, skeletonema costatum, and mesodinium rubrum, were acquired by above water method utilizing spectrometer manufactured by FieldSpec Dual VNIR (USA). It is emphasized that the characteristic reflectance peak lying between 687 and 728 nm can be used to distinguish between red tide and normal sea water. Also the spectral discrepancy between different dominant species of red tide is pointed out, which could be utilized to identify certain red tide species by remote sensing technique. Mechanisms of phytoplankton red tide spectra peaks and vales are given. Spectral characteristics of mesodinium rubrum, a kind of protozoan, may be related to its symbiotic alga in its body and phytoplankton pigment crumb. So, research on ingestion preference, symbiotic property with algae, and fluorescence emission character of such symbiotic algae under normal temperature may be helpful for the deep understanding of mechanism of mesodinium rubrum spectra.

  4. The importance of weightlessness and tides in teaching gravitation

    NASA Astrophysics Data System (ADS)

    Galili, I.; Lehavi, Y.

    2003-11-01

    We examine the presentation of the weight, weightlessness, and tides in university-level physics textbooks. Introductory textbooks often do not discuss tidal forces even though their understanding would be useful for understanding weightlessness. The explanations of tides often miss the free gravitational motion of both interacting objects, which is essential for the symmetry of tidal deformation. The shortcomings in the explanations of weightlessness and tides as provided by students and teachers are compared to textbook discussions. We suggest that an explicit discussion of the different definitions of weight and a synergetic presentation of weightlessness and tides might lead to a better understanding of gravitation. Our approach is illustrated by examples of tidal effects appropriate for introductory courses.

  5. Nonlinear Tides in Close Binary Systems

    NASA Astrophysics Data System (ADS)

    Weinberg, Nevin N.; Arras, Phil; Quataert, Eliot; Burkart, Josh

    2012-06-01

    We study the excitation and damping of tides in close binary systems, accounting for the leading-order nonlinear corrections to linear tidal theory. These nonlinear corrections include two distinct physical effects: three-mode nonlinear interactions, i.e., the redistribution of energy among stellar modes of oscillation, and nonlinear excitation of stellar normal modes by the time-varying gravitational potential of the companion. This paper, the first in a series, presents the formalism for studying nonlinear tides and studies the nonlinear stability of the linear tidal flow. Although the formalism we present is applicable to binaries containing stars, planets, and/or compact objects, we focus on non-rotating solar-type stars with stellar or planetary companions. Our primary results include the following: (1) The linear tidal solution almost universally used in studies of binary evolution is unstable over much of the parameter space in which it is employed. More specifically, resonantly excited internal gravity waves in solar-type stars are nonlinearly unstable to parametric resonance for companion masses M' >~ 10-100 M ⊕ at orbital periods P ≈ 1-10 days. The nearly static "equilibrium" tidal distortion is, however, stable to parametric resonance except for solar binaries with P <~ 2-5 days. (2) For companion masses larger than a few Jupiter masses, the dynamical tide causes short length scale waves to grow so rapidly that they must be treated as traveling waves, rather than standing waves. (3) We show that the global three-wave treatment of parametric instability typically used in the astrophysics literature does not yield the fastest-growing daughter modes or instability threshold in many cases. We find a form of parametric instability in which a single parent wave excites a very large number of daughter waves (N ≈ 103[P/10 days] for a solar-type star) and drives them as a single coherent unit with growth rates that are a factor of ≈N faster than the

  6. Tide Corrections for Coastal Altimetry: Status and Prospects

    NASA Technical Reports Server (NTRS)

    Ray, Richard D.; Egbert, Gary D.

    2008-01-01

    Knowledge of global oceanic tides has markedly advanced over the last two decades, in no small part because of the near-global measurements provided by satellite altimeters, and especially the long and precise Topex/Poseidon time series e.g. [2]. Satellite altimetry in turn places very severe demands on the accuracy of tidal models. The reason is clear: tides are by far the largest contributor to the variance of sea-surface elevation, so any study of non-tidal ocean signals requires removal of this dominant tidal component. Efforts toward improving models for altimetric tide corrections have understandably focused on deep-water, open-ocean regions. These efforts have produced models thought to be generally accurate to about 2 cm rms. Corresponding tide predictions in shelf and near-coastal regions, however, are far less accurate. This paper discusses the status of our current abilities to provide near-global tidal predictions in shelf and near-coastal waters, highlights some of the difficulties that must be overcome, and attempts to divine a path toward some degree of progress. There are, of course, many groups worldwide who model tides over fairly localized shallow-water regions, and such work is extremely valuable for any altimeter study limited to those regions, but this paper considers the more global models necessary for the general user. There have indeed been efforts to patch local and global models together, but such work is difficult to maintain over many updates and can often encounter problems of proprietary or political nature. Such a path, however, might yet prove the most fruitful, and there are now new plans afoot to try again. As is well known, tides in shallow waters tend to be large, possibly nonlinear, and high wavenumber. The short spatial scales mean that current mapping capabilities with (multiple) nadir-oriented altimeters often yield inadequate coverage. This necessitates added reliance on numerical hydrodynamic models and data assimilation

  7. Storm surge and tide interaction: a complete paradigm

    NASA Astrophysics Data System (ADS)

    Horsburgh, Kevin; Williams, Jane; Proctor, Robert

    2014-05-01

    Globally, 200 million people live on coastal floodplains and about 1 trillion worth of assets lie within 1 metre of mean sea level. Any change in the statistics of flood frequency or severity would impact on economic and social systems. It is therefore crucial to understand the physical drivers of extreme storm surges, and to have confidence in datasets used for extreme sea level statistics. Much previous research has focussed on the process of tide-surge interaction, and it is now widely accepted that the physical basis of tide-surge interaction is that a phase shift of the tidal signal represents the effect of the surge on the tide. The second aspect of interaction is that shallow water momentum considerations imply that differing tidal states should modulate surge generation: wind stress should have greater surge-generating potential on lower tides. This has been shown previously by analytical models but not as yet confirmed by fully non-linear models of the continental shelf. We present results from an operational model of the European shelf that demonstrate that tidal range does have an effect on the surges generated. The cycle-integrated effects of wind stress (i.e. the skew surge) are generally greater when tidal range is low. Our results contradict the absence of any such correlation observed in the complete record of UK tide gauge data. This suggests that whilst the modulating effect of the tide on the skew surge (the time-independent difference between peak prediction and observations) is significant, the difference between individual storms is dominant. This implies that forecasting systems must predict salient detail of the most intense storms. A further implication is that operational models need to simulate tides with acceptable accuracy at all coastal locations. We extend our model analysis to show that the same modulation of storm surges (by tidal conditions) applies to tropical cyclones. We conduct simulations using a mature operational storm surge

  8. Storm Surge and Tide Interaction: A Complete Paradigm

    NASA Astrophysics Data System (ADS)

    Horsburgh, K.

    2014-12-01

    Estimates show that in 2005, in the largest 136 coastal cities, there were 40 million people and 3,000 billion of assets exposed to 1 in 100 year coastal flood events. Mean sea level rise will increase this exposure to 150 million people and 35,000 billion of assets by 2070. Any further change in the statistics of flood frequency or severity would impact severely on economic and social systems. It is therefore crucial to understand the physical drivers of extreme storm surges, and to have confidence in datasets used for extreme sea level statistics. Much previous research has focussed on the process of tide-surge interaction, and it is now widely accepted that the physical basis of tide-surge interaction is that a phase shift of the tidal signal represents the effect of the surge on the tide. The second aspect of interaction is that shallow water momentum considerations imply that differing tidal states should modulate surge generation: wind stress should have greater surge-generating potential on lower tides. We present results from a storm surge model of the European shelf that demonstrate that tidal range does have an effect on the surges generated. The cycle-integrated effects of wind stress (i.e. the skew surge) are greater when tidal range is low. Our results contradict the absence of any such correlation in tide gauge records. This suggests that whilst the modulating effect of the tide on the skew surge (the time-independent difference between peak prediction and observations) is significant, the difference between individual storms is dominant. This implies that forecasting systems must predict salient detail of the most intense storms. A further implication is that flood forecasting models need to simulate tides with acceptable accuracy at all coastal locations. We extend our model analysis to show that the same modulation of storm surges (by tidal conditions) applies to tropical cyclones. We conduct simulations using a mature operational storm surge model

  9. Physical activity levels of community-dwelling older adults are influenced by winter weather variables.

    PubMed

    Jones, G R; Brandon, C; Gill, D P

    2017-07-01

    Winter weather conditions may negatively influence participation of older adults in daily physical activity (PA). Assess the influence of winter meteorological variables, day-time peak ambient temperature, windchill, humidity, and snow accumulation on the ground to accelerometer measured PA values in older adults. 50 community-dwelling older adults (77.4±4.7yrs; range 71-89; 12 females) living in Southwestern Ontario (Latitude 42.9°N Longitude 81.2° W) Canada, wore a waist-borne accelerometer during active waking hours (12h) for 7 consecutive days between February and April 2007. Hourly temperature, windchill, humidity, and snowfall accumulation were obtained from meteorological records and time locked to hourly accelerometer PA values. Regression analysis revealed significant relationships between time of day, ambient daytime high temperature and a humidity for participation in PA. Windchill temperature added no additional influence over PA acclamation already influenced by ambient day-time temperature and the observed variability in PA patterns relative to snow accumulation over the study period was too great to warrant its inclusion in the model. Most PA was completed in the morning hours and increased as the winter month's transitioned to spring (February through April). An equation was developed to adjust for winter weather conditions using temperature, humidity and time of day. Accurate PA assessment during the winter months must account for the ambient daytime high temperatures, humidity, and time of day. These older adults were more physically active during the morning hours and became more active as the winter season transitioned to spring. Copyright © 2017 Elsevier B.V. All rights reserved.

  10. Validation of two (parametric vs non-parametric) daily weather generators

    NASA Astrophysics Data System (ADS)

    Dubrovsky, M.; Skalak, P.

    2015-12-01

    As the climate models (GCMs and RCMs) fail to satisfactorily reproduce the real-world surface weather regime, various statistical methods are applied to downscale GCM/RCM outputs into site-specific weather series. The stochastic weather generators are among the most favourite downscaling methods capable to produce realistic (observed-like) meteorological inputs for agrological, hydrological and other impact models used in assessing sensitivity of various ecosystems to climate change/variability. To name their advantages, the generators may (i) produce arbitrarily long multi-variate synthetic weather series representing both present and changed climates (in the latter case, the generators are commonly modified by GCM/RCM-based climate change scenarios), (ii) be run in various time steps and for multiple weather variables (the generators reproduce the correlations among variables), (iii) be interpolated (and run also for sites where no weather data are available to calibrate the generator). This contribution will compare two stochastic daily weather generators in terms of their ability to reproduce various features of the daily weather series. M&Rfi is a parametric generator: Markov chain model is used to model precipitation occurrence, precipitation amount is modelled by the Gamma distribution, and the 1st order autoregressive model is used to generate non-precipitation surface weather variables. The non-parametric GoMeZ generator is based on the nearest neighbours resampling technique making no assumption on the distribution of the variables being generated. Various settings of both weather generators will be assumed in the present validation tests. The generators will be validated in terms of (a) extreme temperature and precipitation characteristics (annual and 30-years extremes and maxima of duration of hot/cold/dry/wet spells); (b) selected validation statistics developed within the frame of VALUE project. The tests will be based on observational weather series

  11. Explaining the road accident risk: weather effects.

    PubMed

    Bergel-Hayat, Ruth; Debbarh, Mohammed; Antoniou, Constantinos; Yannis, George

    2013-11-01

    This research aims to highlight the link between weather conditions and road accident risk at an aggregate level and on a monthly basis, in order to improve road safety monitoring at a national level. It is based on some case studies carried out in Work Package 7 on "Data analysis and synthesis" of the EU-FP6 project "SafetyNet-Building the European Road Safety Observatory", which illustrate the use of weather variables for analysing changes in the number of road injury accidents. Time series analysis models with explanatory variables that measure the weather quantitatively were used and applied to aggregate datasets of injury accidents for France, the Netherlands and the Athens region, over periods of more than 20 years. The main results reveal significant correlations on a monthly basis between weather variables and the aggregate number of injury accidents, but the magnitude and even the sign of these correlations vary according to the type of road (motorways, rural roads or urban roads). Moreover, in the case of the interurban network in France, it appears that the rainfall effect is mainly direct on motorways--exposure being unchanged, and partly indirect on main roads--as a result of changes in exposure. Additional results obtained on a daily basis for the Athens region indicate that capturing the within-the-month variability of the weather variables and including it in a monthly model highlights the effects of extreme weather. Such findings are consistent with previous results obtained for France using a similar approach, with the exception of the negative correlation between precipitation and the number of injury accidents found for the Athens region, which is further investigated. The outlook for the approach and its added value are discussed in the conclusion. Copyright © 2013. Published by Elsevier Ltd.

  12. Synopsis of the Review on Space Weather in Latin America: Space Science, Research Networks and Space Weather Center

    NASA Astrophysics Data System (ADS)

    Denardini, Clezio Marcos; Dasso, Sergio; Gonzalez-Esparza, Americo

    2016-07-01

    The present work is a synopsis of a three-part review on space weather in Latin America. The first paper (part 1) comprises the evolution of several Latin American institutions investing in space science since the 1960's, focusing on the solar-terrestrial interactions, which today is commonly called space weather. Despite recognizing advances in space research in all of Latin America, this part 1 is restricted to the development observed in three countries in particular (Argentina, Brazil and Mexico), due to the fact that these countries have recently developed operational centers for monitoring space weather. The review starts with a brief summary of the first groups to start working with space science in Latin America. This first part of the review closes with the current status and the research interests of these groups, which are described in relation to the most significant works and challenges of the next decade in order to aid in the solving of space weather open issues. The second paper (part 2) comprises a summary of scientific challenges in space weather research that are considered to be open scientific questions and how they are being addressed in terms of instrumentation by the international community, including the Latin American groups. We also provide an inventory of the networks and collaborations being constructed in Latin America, including details on the data processing, capabilities and a basic description of the resulting variables. These instrumental networks currently used for space science research are gradually being incorporated into the space weather monitoring data pipelines as their data provides key variables for monitoring and forecasting space weather, which allow these centers to monitor space weather and issue warnings and alerts. The third paper (part 3) presents the decision process for the spinning off of space weather prediction centers from space science groups with our interpretation of the reason/opportunities that leads to

  13. Global structure and seasonal variability of the migrating terdiurnal tide in the mesosphere and lower thermosphere

    NASA Astrophysics Data System (ADS)

    Yue, Jia; Xu, Jiyao; Chang, Loren C.; Wu, Qian; Liu, Han-Li; Lu, Xian; Russell, James

    2013-12-01

    The morphology of the migrating terdiurnal tide with zonal wavenumber 3 (TW3) in the mesosphere and lower thermosphere (MLT) is revealed using the TIMED satellite datasets from the Sounding of the Atmosphere using Broadband Emission Radiometry (SABER) and the TIMED Doppler Interferometer (TIDI) instruments from 2002 to 2009, as well as the Thermosphere Ionosphere Mesosphere Electrodynamics General Circulation Model (TIME-GCM). The annual mean structures of the TW3 from the TIME-GCM clearly resemble the first real symmetric (3,3) Hough mode. The TW3 temperature and zonal wind components have three peaks at midlatitudes and near the equator, while the TW3 meridional wind components show four peaks at mid and low latitudes. These features are consistent with those resolved in SABER temperature and TIDI zonal wind above ~95 km. TW3 components in the TIME-GCM are stronger during winter and spring months at midlatitudes, which is in agreement with previous ground-based radar measurements. On the other hand, TW3 components of temperature, zonal and meridional winds from SABER and TIDI display different seasonal variations at different altitudes and latitudes. The results presented in this paper will provide an observational basis for further modeling study of terdiurnal tide impacts on the thermosphere and ionosphere.

  14. Oceanic tide maps and spherical harmonic coefficients from Geosat altimetry

    NASA Technical Reports Server (NTRS)

    Cartwright, D. E.; Ray, R. D.; Sanchez, B. V.

    1991-01-01

    Maps and tables for the global ocean tides, 69 degree N to 68 degree S, derived from two years of Geosat altimetry are presented. Global maps of local and Greenwich admittance of the (altimetric) ocean tide, and maps of amplitude and Greenwich phase lag of the ocean tide are shown for M(sub 2), S(sub 2), N(sub 2), O(sub 1), and K(sub 1). Larger scale maps of amplitude and phases are also shown for regional areas of special interest. Spherical harmonic coefficients of the ocean tide through degree and order 8 are tabulated for the six major constituents.

  15. The self-consistent dynamic pole tide in non-global oceans

    NASA Technical Reports Server (NTRS)

    Dickman, S. R.

    1988-01-01

    The dynamic pole tide is determined by solving Laplace tide equations which take into account the presence of continents in oceans, oceanic self-gravitation and loading, and mantle elasticity. Dynamical effects are found to be only mild. It is shown that the dynamical pole tide contributes about one day more to the Chandler period than a static pole tide would, and dissipates wobble energy at a very weak rate. It is noted that, depending on the wobble period predicted for an oceanless elastic earth, mantle anelasticity at low frequencies may nevertheless contribute negligibly to the Chandler period.

  16. Palaeoclimate: ocean tides and Heinrich events.

    PubMed

    Arbic, Brian K; Macayeal, Douglas R; Mitrovica, Jerry X; Milne, Glenn A

    2004-11-25

    Climate varied enormously over the most recent ice age--for example, large pulses of ice-rafted debris, originating mainly from the Labrador Sea, were deposited into the North Atlantic at roughly 7,000-year intervals, with global climatic implications. Here we show that ocean tides within the Labrador Sea were exceptionally large over the period spanning these huge, abrupt ice movements, which are known as Heinrich events. We propose that tides played a catalytic role in liberating iceberg armadas during that time.

  17. Lunar tidal acceleration obtained from satellite-derived ocean tide parameters

    NASA Technical Reports Server (NTRS)

    Goad, C. C.; Douglas, B. C.

    1978-01-01

    Observation equations for the M2 ocean tide are computed from Geos 3 data for the long periodic variations of the inclination and node of the orbit. M2 ocean tide parameter values C22+ = 3.23 + or - 0.25 cm, epsilon 22+ = 331 + or - 6 deg, and epsilon 42+ = 113 + or - 6 deg are determined. With the assumption of zero solid tide phase lag, the lunar tidal acceleration is mostly (85%) due to the C22+ term in the expansion of the M2 tide with additional small contributions from the O1 and N2 tides. The calculated value for the tidal acceleration in lunar longitude is -27.4 + or - 3 arc sec/sq (100 yr) which is similar to values determined from astronomical data. The mean elements of Geos 3 are presented in tabular form.

  18. M2 Internal Tides and Their Observed Wavenumber Spectra from Satellite Altimetry*

    NASA Technical Reports Server (NTRS)

    Ray, R. D.; Zaron, E. D.

    2015-01-01

    A near-global chart of surface elevations associated with the stationary M2 internal tide is empirically constructed from multi-mission satellite altimeter data. An advantage of a strictly empirical mapping approach is that results are independent of assumptions about ocean wave dynamics and, in fact, can be used to test such assumptions. A disadvantage is that present-day altimeter coverage is only marginally adequate to support mapping such short-wavelength features. Moreover, predominantly north-south ground-track orientations and contamination from nontidal oceanographic variability can lead to deficiencies in mapped tides. Independent data from Cryosphere Satellite-2 (CryoSat-2) and other altimeters are used to test the solutions and show positive reduction in variance except in regions of large mesoscale variability. The tidal fields are subjected to two-dimensional wavenumber spectral analysis, which allows for the construction of an empirical map of modal wavelengths. Mode-1 wavelengths show good agreement with theoretical wavelengths calculated from the ocean's mean stratification, with a few localized exceptions (e.g., Tasman Sea). Mode-2 waves are detectable in much of the ocean, with wavelengths in reasonable agreement with theoretical expectations, but their spectral signatures grow too weak to map in some regions.

  19. Development of compound microsatellite markers in red-tide-causing dinoflagellate Akashiwo sanguinea (Dinophyceae).

    PubMed

    Cho, S-Y; Nagai, S; Nishitani, G; Han, M-S

    2009-05-01

    We isolated 13 polymorphic microsatellites from the red-tide causing dinoflagellate Akashiwo sanguinea. These loci were highly variable, with between 2 and 10 alleles per locus, and estimated gene diversity ranging from 0.08 to 0.82. These loci have the potential to reveal genetic structure and estimate gene flow among A. sanguinea populations. © 2009 The Authors. Journal compilation © 2009 Blackwell Publishing Ltd.

  20. Construction of Green Tide Monitoring System and Research on its Key Techniques

    NASA Astrophysics Data System (ADS)

    Xing, B.; Li, J.; Zhu, H.; Wei, P.; Zhao, Y.

    2018-04-01

    As a kind of marine natural disaster, Green Tide has been appearing every year along the Qingdao Coast, bringing great loss to this region, since the large-scale bloom in 2008. Therefore, it is of great value to obtain the real time dynamic information about green tide distribution. In this study, methods of optical remote sensing and microwave remote sensing are employed in Green Tide Monitoring Research. A specific remote sensing data processing flow and a green tide information extraction algorithm are designed, according to the optical and microwave data of different characteristics. In the aspect of green tide spatial distribution information extraction, an automatic extraction algorithm of green tide distribution boundaries is designed based on the principle of mathematical morphology dilation/erosion. And key issues in information extraction, including the division of green tide regions, the obtaining of basic distributions, the limitation of distribution boundary, and the elimination of islands, have been solved. The automatic generation of green tide distribution boundaries from the results of remote sensing information extraction is realized. Finally, a green tide monitoring system is built based on IDL/GIS secondary development in the integrated environment of RS and GIS, achieving the integration of RS monitoring and information extraction.

  1. Treatment of ocean tide aliasing in the context of a next generation gravity field mission

    NASA Astrophysics Data System (ADS)

    Hauk, Markus; Pail, Roland

    2018-04-01

    Current temporal gravity field solutions from GRACE suffer from temporal aliasing errors due to under-sampling of signal to be recovered (e.g. hydrology), uncertainties in the de-aliasing models (usually atmosphere and ocean), and imperfect ocean tide models. Especially the latter will be one of the most limiting factors in determining high resolution temporal gravity fields from future gravity missions such as GRACE Follow-on and Next-Generation Gravity Missions (NGGM). In this paper a method to co-parameterize ocean tide parameters of the 8 main tidal constituents over time spans of several years is analysed and assessed. Numerical closed-loop simulations of low-low satellite-to-satellite-tracking missions for a single polar pair and a double pair Bender-type formation are performed, using time variable geophysical background models and noise assumptions for new generation instrument technology. Compared to the single pair mission, results show a reduction of tide model errors up to 70 per cent for dedicated tidal constituents due to an enhanced spatial and temporal sampling and error isotropy for the double pair constellation. Extending the observation period from one to three years leads to a further reduction of tidal errors up to 60 per cent for certain constituents, and considering non-tidal mass changes during the estimation process leads to reductions of tidal errors between 20 per cent and 80 per cent. As part of a two-step approach, the estimated tide model is used for de-aliasing during gravity field retrieval in a second iteration, resulting in more than 50 per cent reduction of ocean tide aliasing errors for a NGGM Bender-type formation.

  2. Treatment of ocean tide aliasing in the context of a next generation gravity field mission

    NASA Astrophysics Data System (ADS)

    Hauk, Markus; Pail, Roland

    2018-07-01

    Current temporal gravity field solutions from Gravity Recovery and Climate Experiment (GRACE) suffer from temporal aliasing errors due to undersampling of signal to be recovered (e.g. hydrology), uncertainties in the de-aliasing models (usually atmosphere and ocean) and imperfect ocean tide models. Especially the latter will be one of the most limiting factors in determining high-resolution temporal gravity fields from future gravity missions such as GRACE Follow-On and Next-Generation Gravity Missions (NGGM). In this paper a method to co-parametrize ocean tide parameters of the eight main tidal constituents over time spans of several years is analysed and assessed. Numerical closed-loop simulations of low-low satellite-to-satellite-tracking missions for a single polar pair and a double pair Bender-type formation are performed, using time variable geophysical background models and noise assumptions for new generation instrument technology. Compared to the single pair mission, results show a reduction of tide model errors up to 70 per cent for dedicated tidal constituents due to an enhanced spatial and temporal sampling and error isotropy for the double pair constellation. Extending the observation period from 1 to 3 yr leads to a further reduction of tidal errors up to 60 per cent for certain constituents, and considering non-tidal mass changes during the estimation process leads to reductions of tidal errors between 20 and 80 per cent. As part of a two-step approach, the estimated tide model is used for de-aliasing during gravity field retrieval in a second iteration, resulting in more than 50 per cent reduction of ocean tide aliasing errors for a NGGM Bender-type formation.

  3. Influence of parameterized small-scale gravity waves on the migrating diurnal tide in Earth's thermosphere

    NASA Astrophysics Data System (ADS)

    Yiǧit, Erdal; Medvedev, Alexander S.

    2017-04-01

    Effects of subgrid-scale gravity waves (GWs) on the diurnal migrating tides are investigated from the mesosphere to the upper thermosphere for September equinox conditions, using a general circulation model coupled with the extended spectral nonlinear GW parameterization of Yiğit et al. (). Simulations with GW effects cut off above the turbopause and included in the entire thermosphere have been conducted. GWs appreciably impact the mean circulation and cool the thermosphere down by up to 12-18%. GWs significantly affect the winds modulated by the diurnal migrating tide, in particular, in the low-latitude mesosphere and lower thermosphere and in the high-latitude thermosphere. These effects depend on the mutual correlation of the diurnal phases of the GW forcing and tides: GWs can either enhance or reduce the tidal amplitude. In the low-latitude MLT, the correlation between the direction of the deposited GW momentum and the tidal phase is positive due to propagation of a broad spectrum of GW harmonics through the alternating winds. In the Northern Hemisphere high-latitude thermosphere, GWs act against the tide due to an anticorrelation of tidal wind and GW momentum, while in the Southern high-latitudes they weakly enhance the tidal amplitude via a combination of a partial correlation of phases and GW-induced changes of the circulation. The variable nature of GW effects on the thermal tide can be captured in GCMs provided that a GW parameterization (1) considers a broad spectrum of harmonics, (2) properly describes their propagation, and (3) correctly accounts for the physics of wave breaking/saturation.

  4. Estimating Tides from a Planetary Flyby Mission

    NASA Astrophysics Data System (ADS)

    Mazarico, Erwan; Genova, Antonio; Smith, David; Zuber, Maria; Sun, Xiaoli

    2014-05-01

    Previous and current laser altimeter instruments (e.g. MOLA, NLR, LOLA, MLA) acquired measurements in orbit to provide global topography and study the surface and sub-surface properties of planetary bodies. We show that altimetric data from multiple flybys can make significant contributions to the geophysical understanding of the target body. In particular, the detection of the body tide (e.g. surface deformation due to the tides raised by the Sun or the parent body) and the estimation of its amplitude can yield critical information about the interior structure. We conduct a full simulation of a planetary flyby mission around Europa. We use the GEODYN II program developed and maintained at NASA GSFC to process altimetric and radiometric tracking data created using truth models. The data are processed in short two-day segments (arcs) centered on each closest approach. The initial trajectory is integrated using a priori (truth) models of the planetary ephemeris, the gravity field, the tidal Love numbers k2 and h2 (which describe the amplitudes of the time-variable tidal potential and the time-variable radial deformation respectively). The gravity field is constructed using a Kaula-like power law and scaling considerations from other planetary bodies. The global-scale static topography is also chosen to follow a power law, and higher-resolution local maps consistent with recent stereo-topography work are used to assess the expected variations along altimetric profiles. We assume realistic spacecraft orientation to drive a spacecraft macro-model and model the solar radiation pressure acceleration. Radiometric tracking data are generated from the truth trajectory accounting for geometry (occultations by Europa or Jupiter or the Sun), DSN visibility and scheduling (8h per day) and measurement noise (Ka-band quality, plasma noise). Doppler data have a 10-second integration step while Range data occur every 5 minutes. The altimetric data are generated using realistic

  5. The San Juan Delta, Colombia: tides, circulations, and salt dispersion

    NASA Astrophysics Data System (ADS)

    Restrepo, Juan D.; Kjerfve, Björn

    2002-05-01

    The San Juan River delta (Colombia) with an area of 800 km 2 is the largest delta environment on the Pacific coast of South America. It consists of active distributaries maintained by an average discharge of 2500 m 3 s -1, is tide dominated, and has relatively narrow estuarine mixing zones <17 km wide and typically ˜7 km wide. Water level and current time series in two distributary mouths indicate that the tide is semidiurnal with a form number 0.1-0.2 and a mean range of 3 m. Processes at tidal frequencies explain 75-95% of the water level variability with the remaining low-frequency variability attributed to meteorological forcing and river processes. The tidal phase for the main diurnal and semidiurnal constituents progress from north to south along the coast. Only the southernmost distributary experiences significant tidal asymmetry as a result of strong river discharge and shallow depths. In the northernmost distributary, shallow water constituents are insignificant. Tidal currents were more semidiurnal than the water level, with form number 0.09-0.13. Tidal ellipses indicated that currents were aligned with the channels and mean amplitudes <1 m s -1. In the delta distributaries, circulation modes varied from seaward flow at all depths during intermediate runoff conditions to gravitational circulation during rising and high discharge periods. In San Juan and Chavica distributaries, the currents were ebb-directed, while in Charambirá they were flood-directed. The circulation appears to be controlled by the morphology of the distributaries, which were weakly stratified and only sometimes moderately stratified. The net salt transport was directed seaward in San Juan and Charambirá, and landward at Chavica, indicating an imbalance in the salt budget, and signifying non-steady state behavior. The net longitudinal salt flux in the San Juan delta is largely a balance between ebb-directed advective flux, and flood-directed tidal sloshing. Along the distributary

  6. What caused the rise of water level in the battle of Luermen bay in 1661? Tsunami, Storm surge, or Tide?

    NASA Astrophysics Data System (ADS)

    Wu, Tso-Ren; Wu, Han; Tsai, Yu-Lin

    2016-04-01

    In 1661, Chinese navy led by General Zheng Chenggong at the end of Ming Dynasty had a naval battle against Netherlands. This battle was not only the first official sea warfare that China confronted the Western world, but also the only naval battle won by Chinese Navy so far. This event was important because it changed the fate of Taiwan until today. One of the critical points that General Zheng won the battle was entering Luermen bay unexpected. Luermen bay was and is an extreme shallow bay with a 2.1m maximum water depth during the high tide, which was not possible for a fleet of 20,000 marines to across. Therefore, no defense was deployed from the Netherlands side. However, plenty of historical literatures mentioned a strange phenomenon that helped Chinese warships entered the Luermen bay, the rise of water level. In this study, we will discuss the possible causes that might rise the water level, e.g. Tsunami, storm surge, and high tide. We analyzed it based on the knowledge of hydrodynamics. We performed the newly developed Impact Intensify Analysis (IIA) for finding the potential tsunami sources, and the COMCOT tsunami model was adopted for the nonlinear scenario simulations, associated with the high resolution bathymetry data. Both earthquake and mudslide tsunamis were inspected. Other than that, we also collected the information of tide and weather for identifying the effects form high tide and storm surge. After the thorough study, a scenario that satisfy most of the descriptions in the historical literatures will be presented. The results will explain the cause of mysterious event that changed the destiny of Taiwan.

  7. Medium-range fire weather forecasts

    Treesearch

    J.O. Roads; K. Ueyoshi; S.C. Chen; J. Alpert; F. Fujioka

    1991-01-01

    The forecast skill of theNational Meteorological Center's medium range forecast (MRF) numerical forecasts of fire weather variables is assessed for the period June 1,1988 to May 31,1990. Near-surface virtual temperature, relative humidity, wind speed and a derived fire weather index (FWI) are forecast well by the MRF model. However, forecast relative humidity has...

  8. Lunar tides in the Thermosphere-Ionosphere-Electrodynamics General Circulation Model

    NASA Astrophysics Data System (ADS)

    Stening, R. J.; Richmond, A. D.; Roble, R. G.

    1999-01-01

    Lunar semidiurnal tides are introduced at the lower boundary of the National Center for Atmospheric Research Thermosphere-Ionosphere-Electrodynamics General Circulation Model (TIEGCM). The tides are derived from the model of Vial and Forbes [1994] and interesting properties of these tides are found when they are subjected to Hough decomposition; there is considerable hemispherical antisymmetry in the September tides, and the March and September modal compositions are significantly different. A differencing method is used to isolate the lunar tidal effects in the TIEGCM, and these are compared with lunar tidal analyses of ionospheric data. The model reproduces the broad features of the lunar tide in foF2 (maximum frequency of the F region) with phase changes around 7° magnetic dip latitude during daytime. The model and data analysis both give variations of the amplitude and phase of the lunar tide with local time. Near the equator the variation of phase with local time changes with latitude as the equatorial anomaly develops during the day. Comparison between the model predictions and analyses of data at observatories at midlatitudes produces mixed results. Here the effects of the lunar components of both electrodynamic drifts and of neutral winds need to be taken into account. Several cases of day to night changes in the phase of the lunar tide in foF2 are noted. Large nighttime amplitudes of the lunar tide in hmF2 (height of the maximum density), more than 4 km, seem to be due to inphase action of the electrodynamic and neutral wind effects while during daytime they are out of phase. The lunar tide in the ratio of oxygen to nitrogen density [O]/[N2] is estimated and found to be of relatively minor importance. Amplitudes of the lunar tide in foF2 may be measured at more than 0.4 MHz at some local times, but the model values are less than this. Comparison is also made with ion drift measurements made by the San Marco D satellite. The several uncertainties which

  9. Orbital Evolution of Planetesimals by the Galactic Tide

    NASA Astrophysics Data System (ADS)

    Higuchi, A.; Kokubo, E.; Mukai, T.

    2005-05-01

    The Oort cloud is a spherical comet reservoir surrounding the solar system. There is general agreement that the Oort cloud comets are the residual planetesimals of planet formation. The standard scenario of the Oort cloud formation consists of two dynamical stages: (1) giant planets raise the aphelia of planetesimals to the outer region of the solar system and (2) the galactic tide, passing stars, and giant molecular clouds pull up their perihelia out of the planetary region. Here we show the orbital evolution of planetesimals by the galactic tide. Planetesimals with large aphelion distances change their perihelion distances toward the outside of the planetary region by the galactic tide and become members of the Oort cloud. The effect of the galactic tide on the planetesimals with semimajor axes of ˜ 104AU is about 10-3 of the solar gravity. The timescale of the orbital evolution is ˜ 108 years. We consider only the vertical component of the galactic tide. Under the axisymmetric potential, some planetesimals may show the librations around ω (argument of perihelion)=π /2 and 3π /2 (the Kozai mechanism). The alternate increases of eccentricity and inclination of the Kozai mechanism are effective to form the Oort cloud. The secular perturbation theory demonstrates the Kozai mechanism and we can understand the motion of the planetesimals analytically. We apply the Kozai mechanism to the galactic tide and discuss the property of the Oort cloud formed by the Kozai mechanizm. This work was supported by the 21st Century COE Program Origin and Evolution of Planetary Systems of the Ministry of Education, Culture, Sports, Science, and Technology, Japan, and JSPS Research Fellowship for Young Scientists.

  10. Non-Migrating Diurnal Tides Generated with Planetary Waves in the Mesosphere

    NASA Technical Reports Server (NTRS)

    Mayr, H. G.; Mengel, J. G.; Talaat, E. R.; Porter, H. S.; Chan, K. L.

    2003-01-01

    We report here the results from a modeling study with our Numerical Spectral Model (NSM) that extends from the ground into thermosphere. The NSM incorporates Hines Doppler Spread Parameterization for small-scale gravity waves (GWs) and describes the major dynamical features of the atmosphere, including the wave driven equatorial oscillations (QBO and SAO), and the seasonal variations of tides and planetary waves. Accounting solely for the solar migrating tidal excitation sources, the NSM generates through dynamical interactions also non-migrating tides in the mesosphere that have amplitudes comparable to those observed. The model produces the diurnal (and semidiurnal) oscillations of the zonal mean (m = 0), and eastward and westward propagating tides for zonal wave numbers m = 1 to 4. To identify the mechanism of excitation for these tides, a numerical experiment is performed. The NSM is run without the heat source for the zonal-mean circulation and temperature variation, and the amplitudes of the resulting nonmigrating tides are then negligibly small. This leads to the conclusion that the planetary waves, which normally are excited in the NSM by instabilities but are suppressed in this case, generate the nonmigrating tides through nonlinear interactions with the migrating tides.

  11. Monitoring Sea Level by Tide Gauges and GPS at Barcelona and Estartit Harbours

    NASA Astrophysics Data System (ADS)

    Martinez Benjamin, J. J.; Gili, J.; Lopez, R.; Tapia, A.; Bosch, E.; Perez, B.; Pros, F.

    2012-04-01

    Sea level is an environmental variable which is widely recognised as being important in many scientific disciplines as a control parameter for coastal dynamical processes or climate processes in the coupled atmosphere-ocean systems, as well as engineering applications. A major source of sea-level data are the national networks of coastal tide gauges, in Spain belonging to different institutions as the Instituto Geográfico Nacional (IGN), Puertos del Estado (PE), Instituto Hidrográfico de la Marina (IHM), etc. The tide gauge of l'Estartit is a traditional floating gauge placed 21 years ago and has an accuracy of ± 2 mm. Since 1996, l'Estartit tide gauge has been co-located with geodetic techniques (GPS measurements of XU, Utilitary Network, and XdA, Levelling Network,) and it is tied to the SPGIC (Integrated Geodetic Positioning System of Catalonia) project of the Cartographic Institute of Catalunya (ICC). In 2006, due to the work for the expansion of the harbour, the tide gauge had to be moved. Before the work started, appropiate GPS measurements were carried out in order to ensure the connection of the tide gauge data. During October 2006 and May 2008, the tide gauge was inactive and it has been moved on to a new location inside the harbour. In June 2008, new GPS and levelling measures have been done in order to tie the new location into SPGIC project and to co-locate old data respect the new one. Although l'Estartit does not have a GPS permanent station, it is possible to build a virtual one from the service "CATNET web" of the ICC. "CATNET web" is a data distribution system of a virtual GPS permanent station via web. From the coordinates where you want to place the virtual station, the time interval and the measurement rate, the system generates a RINEX file under the requested conditions. At Barcelona harbour there is one MIROS radar tide gauge belonging to Puertos del Estado (Spanish Harbours). It is placed at the dock 140 of the ENAGAS Building.The radar

  12. Weather explains high annual variation in butterfly dispersal

    PubMed Central

    Rytteri, Susu; Heikkinen, Risto K.; Heliölä, Janne; von Bagh, Peter

    2016-01-01

    Weather conditions fundamentally affect the activity of short-lived insects. Annual variation in weather is therefore likely to be an important determinant of their between-year variation in dispersal, but conclusive empirical studies are lacking. We studied whether the annual variation of dispersal can be explained by the flight season's weather conditions in a Clouded Apollo (Parnassius mnemosyne) metapopulation. This metapopulation was monitored using the mark–release–recapture method for 12 years. Dispersal was quantified for each monitoring year using three complementary measures: emigration rate (fraction of individuals moving between habitat patches), average residence time in the natal patch, and average distance moved. There was much variation both in dispersal and average weather conditions among the years. Weather variables significantly affected the three measures of dispersal and together with adjusting variables explained 79–91% of the variation observed in dispersal. Different weather variables became selected in the models explaining variation in three dispersal measures apparently because of the notable intercorrelations. In general, dispersal rate increased with increasing temperature, solar radiation, proportion of especially warm days, and butterfly density, and decreased with increasing cloudiness, rainfall, and wind speed. These results help to understand and model annually varying dispersal dynamics of species affected by global warming. PMID:27440662

  13. Weather explains high annual variation in butterfly dispersal.

    PubMed

    Kuussaari, Mikko; Rytteri, Susu; Heikkinen, Risto K; Heliölä, Janne; von Bagh, Peter

    2016-07-27

    Weather conditions fundamentally affect the activity of short-lived insects. Annual variation in weather is therefore likely to be an important determinant of their between-year variation in dispersal, but conclusive empirical studies are lacking. We studied whether the annual variation of dispersal can be explained by the flight season's weather conditions in a Clouded Apollo (Parnassius mnemosyne) metapopulation. This metapopulation was monitored using the mark-release-recapture method for 12 years. Dispersal was quantified for each monitoring year using three complementary measures: emigration rate (fraction of individuals moving between habitat patches), average residence time in the natal patch, and average distance moved. There was much variation both in dispersal and average weather conditions among the years. Weather variables significantly affected the three measures of dispersal and together with adjusting variables explained 79-91% of the variation observed in dispersal. Different weather variables became selected in the models explaining variation in three dispersal measures apparently because of the notable intercorrelations. In general, dispersal rate increased with increasing temperature, solar radiation, proportion of especially warm days, and butterfly density, and decreased with increasing cloudiness, rainfall, and wind speed. These results help to understand and model annually varying dispersal dynamics of species affected by global warming. © 2016 The Author(s).

  14. Ocean science. Enhanced: internal tides and ocean mixing.

    PubMed

    Garrett, Chris

    2003-09-26

    Recent satellite and in situ observations have shown that at ocean ridges and other seafloor topographic features, a substantial amount of energy is transferred from the main ocean tides into "internal tides." In his Perspective, Garrett explains how these internal waves with tidal periods propagate through the density-stratified deep ocean and eventually break down into turbulence. The resulting mixing affects ocean stratification and ocean circulation. It thus influences climate as well as biological production. The energy for the internal tides is derived from the rotational energy of the Earth-Moon system changes of the length of the day and the distance to the Moon.

  15. Mapping ocean tides with satellites - A computer simulation

    NASA Technical Reports Server (NTRS)

    Won, I. J.; Kuo, J. T.; Jachens, R. C.

    1978-01-01

    As a preliminary study for the future worldwide direct mapping of the open ocean tide with satellites equipped with precision altimeters we conducted a simulated study using sets of artificially generated altimeter data constructed from a realistic geoid and four pairs of major tides in the northeastern Pacific Ocean. Recovery of the original geoid and eight tidal maps is accomplished by a space-time, least squares harmonic analysis scheme. The resultant maps appear fairly satisfactory even when random noises up to + or - 100 cm are added to the altimeter data of sufficient space-time density. The method also produces a refined geoid which is rigorously corrected for the dynamic tides.

  16. Lunar and Solar Torques on the Oceanic Tides

    NASA Technical Reports Server (NTRS)

    Ray, Richard D.; Bills, Bruce G.; Chao, Benjamin F.

    1998-01-01

    Brosche and Seiler recently suggested that direct lunar and solar tidal torques on the oceanic tides play a significant role in the earth's short-period angular momentum balance ("short-period" here meaning daily and sub-daily). We reexamine that suggestion here, concentrating on axial torques and hence on variations in rotation rate. Only those spherical harmonic components of the ocean tide having the same degree and order as the tidal potential induce nonzero torques. Prograde components (those moving in the same direction as the tide-generating body) produce the familiar secular braking of the earth's rotation. Retrograde components, however, produce rapid variations in UTI at twice the tidal frequency. There also exist interaction torques between tidal constituents, e.g. solar torques on lunar tides. They generate UTI variations at frequencies equal to the sums and differences of the original tidal frequencies. We give estimates of the torques and angular momentum variations for each of the important regimes, secular to quarter-diurnal. For the M(sub 2) potential acting on the M(sub 2) ocean tide, we find an associated angular momentum variation of amplitude 3 x 10(exp 19) N m. This is 5 to 6 orders of magnitude smaller than the angular momentum variations associated with tidal currents. We conclude that these torques do not play a significant role in the short-period angular momentum balance.

  17. An outline of the review on space weather in Latin America: space science, research networks and space weather center

    NASA Astrophysics Data System (ADS)

    De Nardin, C. M.; Dasso, S.; Gonzalez-Esparza, A.

    2016-12-01

    The present work is an outline of a three-part review on space weather in Latin America. The first paper (part 1) comprises the evolution of several Latin American institutions investing in space science since the 1960's, focusing on the solar-terrestrial interactions, which today is commonly called space weather. Despite recognizing advances in space research in all of Latin America, this part 1 is restricted to the development observed in three countries in particular (Argentina, Brazil and Mexico), due to the fact that these countries have recently developed operational centers for monitoring space weather. The review starts with a brief summary of the first groups to start working with space science in Latin America. This first part of the review closes with the current status and the research interests of these groups, which are described in relation to the most significant works and challenges of the next decade in order to aid in the solving of space weather open issues. The second paper (part 2) comprises a summary of scientific challenges in space weather research that are considered to be open scientific questions and how they are being addressed in terms of instrumentation by the international community, including the Latin American groups. We also provide an inventory of the networks and collaborations being constructed in Latin America, including details on the data processing, capabilities and a basic description of the resulting variables. These instrumental networks currently used for space science research are gradually being incorporated into the space weather monitoring data pipelines as their data provides key variables for monitoring and forecasting space weather, which allow these centers to monitor space weather and issue warnings and alerts. The third paper (part 3) presents the decision process for the spinning off of space weather prediction centers from space science groups with our interpretation of the reason/opportunities that leads to

  18. GRACE AOD1B Product Release 06: Long-Term Consistency and the Treatment of Atmospheric Tides

    NASA Astrophysics Data System (ADS)

    Dobslaw, Henryk; Bergmann-Wolf, Inga; Dill, Robert; Poropat, Lea; Flechtner, Frank

    2017-04-01

    The GRACE satellites orbiting the Earth at very low altitudes are affected by rapid changes in the Earth's gravity field caused by mass redistribution in atmosphere and oceans. To avoid temporal aliasing of such high-frequency variability into the final monthly-mean gravity fields, those effects are typically modelled during the numerical orbit integration by appling the 6-hourly GRACE Atmosphere and Ocean De-Aliasing Level-1B (AOD1B) a priori model. In preparation of the next GRACE gravity field re-processing currently performed by the GRACE Science Data System, a new version of AOD1B has been calculated. The data-set is based on 3-hourly surface pressure anomalies from ECMWF that have been mapped to a common reference orography by means of ECMWF's mean sea-level pressure diagnostic. Atmospheric tides as well as the corresponding oceanic response at the S1, S2, S3, and L2 frequencies and its annual modulations have been fitted and removed in order to retain the non-tidal variability only. The data-set is expanded into spherical harmonics complete up to degree and order 180. In this contribution, we will demonstrate that AOD1B RL06 is now free from spurious jumps in the time-series related to occasional changes in ECMWF's operational numerical weather prediction system. We will also highlight the rationale for separating tidal signals from the AOD1B coefficients, and will finally discuss the current quality of the AOD1B forecasts that have been introduced very recently for GRACE quicklook or near-realtime applications.

  19. Eddy Resolving Global Ocean Prediction including Tides

    DTIC Science & Technology

    2013-09-30

    atlantic meridional overturning circulation in the subpolar North Atlantic . Journal of Geophysical Research vol 118, doi:10.1002/jgrc,20065. [published, refereed] ...global ocean circulation model was examined using results from years 2005-2009 of a seven and a half year 1/12.5° global simulation that resolves...internal tides, along with barotropic tides and the eddying general circulation . We examined tidal amplitudes computed using 18 183-day windows that

  20. Effects of tides, vertical discretization schemes and runoff variability on a pan-Arctic Ocean simulation.

    NASA Astrophysics Data System (ADS)

    Luneva, Maria; Holt, Jason; Harle, James; Liu, Hedong

    2013-04-01

    The results of a recently developed NEMO-shelf pan-Arctic Ocean model coupled with LIM2 ice model are presented. This pan Arctic model has a hybrid s-z vertical discretization with terrain following coordinates on the shelf, condensing towards the bottom and surface boundary layer, and partial step z-coordinates in the abyss. This allows (a) processes near the surface to be resolved (b) Cascading (shelf convection), which contributes to the formation of halocline and deep dense water, to be well reproduced; and (c) minimize pressure gradient errors peculiar to terrain following coordinates. Horizontal grid and topography corresponds to global NEMO -ORCA 0.25 model (which uses a tripolar grid) with seamed slit between the western and eastern parts. In the Arctic basin this horizontal resolution corresponds to 15-10km with 5-7 km in the Canadian Archipelago. The model uses the General Length Scale vertical turbulent mixing scheme with (K- ɛ) closure and Kantha and Clayson type structural functions. Smagorinsky type Laplacian diffusivity and viscosity are employed for the description of a horizontal mixing. Vertical Piecewise Parabolic Method has been implemented with the aim to reduce an artificial vertical mixing. Boundary conditions are taken from the 5-days mean output of NOCS version of the global ORCA-025 model and OTPS/tpxo7 for 9 tidal harmonics . For freshwater runoff we employed two different forcings: a climatic one, used in global ORCA-0.25 model, and a recently available data base from Dai and Trenberth (Feb2011) 1948-2007, which takes in account inter-annual variability and includes 1200 river guages for the Arctic ocean coast. The simulations have been performed for two intervals: 1978-1988 and 1997-2007. The model adequately reproduces the main features of dynamics, tides and ice volume/concentration. The analysis shows that the main effects of tides occur at the ice-water interface and bottom boundary layers due to mesoscale Ekman pumping , generated

  1. Research on red tide occurrences using enclosed experimental ecosystems in west Xiamen Harbor, China—Relationship between various factors and red tide occurrences

    NASA Astrophysics Data System (ADS)

    Lin, Yu; Harrison, P. J.

    2000-06-01

    A series of enclosed ecosystem experiments were conducted in a land-based tank near the seaside of West Xiamen Harbor. The results of experiments conducted in different seasons and years showed a repeatable phytoplankton succession. In this relatively stable ecosystem with added nutrients and trace metals, diatoms dominated initially, dinoflagellates dominated in the later stage, and dinoflagellate red tides eventually occurred. Vitamin B12 enrichment may speed up this succession process. Stirring the water column could stop this process. Soluble Mn at a level of 3 4 μg/L in seawater, which also is the existing concentration of soluble Mn in Xiamen Harbor seawater, is sufficient for the multiplication of algae and occurrence of red tide. The present study showed that excessive soluble Mn in Xiamen Harbor cannot cause red tide, and that Fe was one of the important factors causing diatiom red tide in this present study.

  2. Environmental exposures to Florida red tides: Effects on emergency room respiratory diagnoses admissions.

    PubMed

    Kirkpatrick, Barbara; Fleming, Lora E; Backer, Lorraine C; Bean, Judy A; Tamer, Robert; Kirkpatrick, Gary; Kane, Terrance; Wanner, Adam; Dalpra, Dana; Reich, Andrew; Baden, Daniel G

    2006-10-01

    Human exposure to Florida red tides formed by Karenia brevis, occurs from eating contaminated shellfish and inhaling aerosolized brevetoxins. Recent studies have documented acute symptom changes and pulmonary function responses after inhalation of the toxic aerosols, particularly among asthmatics. These findings suggest that there are increases in medical care facility visits for respiratory complaints and for exacerbations of underlying respiratory diseases associated with the occurrence of Florida red tides.This study examined whether the presence of a Florida red tide affected the rates of admission with a respiratory diagnosis to a hospital emergency room in Sarasota, FL. The rate of respiratory diagnoses admissions were compared for a 3-month time period when there was an onshore red tide in 2001 (red tide period) and during the same 3-month period in 2002 when no red tide bloom occurred (non-red tide period). There was no significant increase in the total number of respiratory admissions between the two time periods. However, there was a 19% increase in the rate of pneumonia cases diagnosed during the red tide period compared with the non-red tide period. We categorized home residence zip codes as coastal (within 1.6 km from the shore) or inland (>1.6 km from shore). Compared with the non-red tide period, the coastal residents had a significantly higher (54%) rate of respiratory diagnoses admissions than during the red tide period. We then divided the diagnoses into subcategories (i.e. pneumonia, bronchitis, asthma, and upper airway disease). When compared with the non-red tide period, the coastal zip codes had increases in the rates of admission of each of the subcategories during the red tide period (i.e. 31, 56, 44, and 64%, respectively). This increase was not observed seen in the inland zip codes.These results suggest that the healthcare community has a significant burden from patients, particularly those who live along the coast, needing emergency

  3. The recognition of ocean red tide with hyper-spectral-image based on EMD

    NASA Astrophysics Data System (ADS)

    Zhao, Wencang; Wei, Hongli; Shi, Changjiang; Ji, Guangrong

    2008-05-01

    A new technique is introduced in this paper regarding red tide recognition with remotely sensed hyper-spectral images based on empirical mode decomposition (EMD), from an artificial red tide experiment in the East China Sea in 2002. A set of characteristic parameters that describe absorbing crest and reflecting crest of the red tide and its recognition methods are put forward based on general picture data, with which the spectral information of certain non-dominant alga species of a red tide occurrence is analyzed for establishing the foundation to estimate the species. Comparative experiments have proved that the method is effective. Meanwhile, the transitional area between red-tide zone and non-red-tide zone can be detected with the information of thickness of algae influence, with which a red tide can be forecast.

  4. Highlights of Space Weather Services/Capabilities at NASA/GSFC Space Weather Center

    NASA Technical Reports Server (NTRS)

    Fok, Mei-Ching; Zheng, Yihua; Hesse, Michael; Kuznetsova, Maria; Pulkkinen, Antti; Taktakishvili, Aleksandre; Mays, Leila; Chulaki, Anna; Lee, Hyesook

    2012-01-01

    The importance of space weather has been recognized world-wide. Our society depends increasingly on technological infrastructure, including the power grid as well as satellites used for communication and navigation. Such technologies, however, are vulnerable to space weather effects caused by the Sun's variability. NASA GSFC's Space Weather Center (SWC) (http://science.gsfc.nasa.gov//674/swx services/swx services.html) has developed space weather products/capabilities/services that not only respond to NASA's needs but also address broader interests by leveraging the latest scientific research results and state-of-the-art models hosted at the Community Coordinated Modeling Center (CCMC: http://ccmc.gsfc.nasa.gov). By combining forefront space weather science and models, employing an innovative and configurable dissemination system (iSWA.gsfc.nasa.gov), taking advantage of scientific expertise both in-house and from the broader community as well as fostering and actively participating in multilateral collaborations both nationally and internationally, NASA/GSFC space weather Center, as a sibling organization to CCMC, is poised to address NASA's space weather needs (and needs of various partners) and to help enhancing space weather forecasting capabilities collaboratively. With a large number of state-of-the-art physics-based models running in real-time covering the whole space weather domain, it offers predictive capabilities and a comprehensive view of space weather events throughout the solar system. In this paper, we will provide some highlights of our service products/capabilities. In particular, we will take the 23 January and the 27 January space weather events as examples to illustrate how we can use the iSWA system to track them in the interplanetary space and forecast their impacts.

  5. A Model for Teaching the Dynamical Theory of Tides.

    ERIC Educational Resources Information Center

    Railsback, L. Bruce

    1991-01-01

    The dynamical theory of tides is often neglected in teaching oceanography because students have difficulty in visualizing the movements of the tides across the glove. A schematic diagram portraying amphidromic systems as mechanical gears helps overcome these problems. (Author)

  6. Assessing Weather Curiosity in University Students

    NASA Astrophysics Data System (ADS)

    Stewart, A. E.

    2017-12-01

    This research focuses upon measuring an individual's level of trait curiosity about the weather using the Weather Curiosity Scale (WCS). The measure consists of 15 self-report items that describe weather preferences and/or behaviors that people may perform more or less frequently. The author reports on two initial studies of the WCS that have used the responses of 710 undergraduate students from a large university in the southeastern United States. In the first study, factor analysis of the 15 items indicated that the measure was unidimensional - suggesting that its items singularly assessed weather curiosity. The WCS also was internally consistent as evidenced by an acceptable Cronbach's alpha, a = .81). The second study sought to identify other personality variables that may relate with the WCS scores and thus illuminate the nature of weather curiosity. Several clusters of personality variables appear to underlie the curiosity levels people exhibited, the first of which related to perceptual curiosity (r = .59). Being curious about sights, sounds, smells, and textures generally related somewhat to curiosity about weather. Two measures of trait sensitivity to environmental stimulation, the Highly Sensitive Person Scale (r = .47) and the Orientation Sensitivity Scale of the Adult Temperament Questionnaire (r = .43), also predicted weather curiosity levels. Finally, possessing extraverted personality traits (r = .34) and an intense style of experiencing one's emotions (r = .33) related to weather curiosity. How can this measure be used in K-12 or post-secondary settings to further climate literacy? First, the WCS can identify students with natural curiosities about weather and climate so these students may be given more challenging instruction that will leverage their natural interests. Second, high-WCS students may function as weather and climate ambassadors during inquiry-based learning activities and thus help other students who are not as oriented to the

  7. Modeling influence of tide stages on forecasts of the 2010 Chilean tsunami

    NASA Astrophysics Data System (ADS)

    Uslu, B. U.; Chamberlin, C.; Walsh, D.; Eble, M. C.

    2010-12-01

    The impact of the 2010 Chilean tsunami is studied using the NOAA high-resolution tsunami forecast model augmented to include modeled tide heights in addition to deep-water tsunami propagation as boundary-condition input. The Chilean tsunami was observed at the Los Angeles tide station at mean low water, Hilo at low, Pago Pago at mid tide and Wake Island near high tide. Because the tsunami arrived at coastal communities at a representative variety of tide stages, 2010 Chile tsunami provides opportunity to study the tsunami impacts at different tide levels to different communities. The current forecast models are computed with a constant tidal stage, and this study evaluates techniques for adding an additional varying predicted tidal component in a forecasting context. Computed wave amplitudes, wave currents and flooding are compared at locations around the Pacific, and the difference in tsunami impact due to tidal stage is studied. This study focuses on how tsunami impacts vary with different tide levels, and helps us understand how the inclusion of tidal components can improve real-time forecast accuracy.

  8. The Amazon hydrometeorology: Climatology, variability and links to changes in weather patterns

    NASA Astrophysics Data System (ADS)

    Fernandes, Katia De Avila

    My thesis focuses on improving the quantification of the hydrological cycle and understanding the atmospheric processes that link weather to climate in the Amazon River basin. By using ERA40 and independent observations, I assess how well we can estimate the surface water budget in the Amazon River basin. I find that ERA40 basin wide annual precipitation (P) overall agrees with observations showing a slight underestimation of 10% in average, whereas runoff (R) is underestimated by a larger margin (˜25%). Observed residual of precipitation and runoff (denoted as P-R) is better estimated by ERA40 P-R than actual ET which includes soil moisture nudging. The causes for said discrepancies were found to partly relate to soil moisture nudging that needs to be applied during the dry season to produce realistic ET and compensate for the low soil moisture recharge during the previous wet season. Insufficient recharge may in part be caused by underestimation of rainfall amount and intensity; moreover the shallow root layer in the model does not represent the deep soil water reservoir characteristic of the Amazonian forest. Whether the hydrological cycle and weather patterns in the Amazon have changed during the past few decades is a highly debatable but central question for detecting climate change in the region. The second part of my thesis focus on the physical links between rainfall changes detected in observations, and changes of synoptic scale systems as represented by ERA40. My results suggest that an observed delayed wet season onset is consistent with a decreasing number of cold air incursion (CAI) days in southern Amazon for the period 1979--2001. The variability of CAI into southern Amazon is related to the variability of SST upstream of South America in the tropical Pacific and Indian Oceans. A Singular Value Decomposition Analysis (SVD) between CAI days and global SST reveal three main modes of co-variability. The first mode describes the effect of the El Nino

  9. Altimetry, Orbits and Tides

    NASA Technical Reports Server (NTRS)

    Colombo, O. L.

    1984-01-01

    The nature of the orbit error and its effect on the sea surface heights calculated with satellite altimetry are explained. The elementary concepts of celestial mechanics required to follow a general discussion of the problem are included. Consideration of errors in the orbits of satellites with precisely repeating ground tracks (SEASAT, TOPEX, ERS-1, POSEIDON, amongst past and future altimeter satellites) are detailed. The theoretical conclusions are illustrated with the numerical results of computer simulations. The nature of the errors in this type of orbits is such that this error can be filtered out by using height differences along repeating (overlapping) passes. This makes them particularly valuable for the study and monitoring of changes in the sea surface, such as tides. Elements of tidal theory, showing how these principles can be combined with those pertinent to the orbit error to make direct maps of the tides using altimetry are presented.

  10. The lunar semidiurnal air pressure tide in in-situ data and ECMWF reanalyses

    NASA Astrophysics Data System (ADS)

    Schindelegger, Michael; Dobslaw, Henryk

    2016-04-01

    A gridded empirical model of the lunar semidiurnal air pressure tide L2 is deduced through multiquadric interpolation of more than 2000 globally distributed tidal estimates from land barometers and moored buoys. The resulting climatology serves as an independent standard to validate the barometric L2 oscillations that are present in ECMWF's (European Centre for Medium-Range Weather Forecasts) global atmospheric reanalyses despite the omission of gravitational forcing mechanisms in the involved forecast routines. Inconsistencies between numerical and empirical L2 solutions are found to be small even though the reanalysis models typically underestimate equatorial peak pressures by 10-20% and produce slightly deficient tidal phases in latitudes south of 30°N. Through using a time-invariant reference surface over both land and water and assimilating marine pressure data without accounting for vertical sensor movements due to the M2 ocean tide, ECMWF-based tidal solutions are also prone to strong local artifacts. Additionally, the dependency of the lunar tidal oscillation in atmospheric analysis systems on the meteorological input data is demonstrated based on a recent ECMWF twentieth-century reanalysis (ERA-20C) which draws its all of its observational constraints from in-situ registrations of pressure and surface winds. The L2 signature prior to 1950 is particularly indicative of distinct observing system changes, such as the paucity of marine data during both World Wars or the opening of the Panama Canal in 1914 and the associated adjustment of commercial shipping routes.

  11. The self-consistent dynamic pole tide in global oceans

    NASA Technical Reports Server (NTRS)

    Dickman, S. R.

    1985-01-01

    The dynamic pole tide is characterized in a self-consistent manner by means of introducing a single nondifferential matrix equation compatible with the Liouville equation, modelling the ocean as global and of uniform depth. The deviations of the theory from the realistic ocean, associated with the nonglobality of the latter, are also given consideration, with an inference that in realistic oceans long-period modes of resonances would be increasingly likely to exist. The analysis of the nature of the pole tide and its effects on the Chandler wobble indicate that departures of the pole tide from the equilibrium may indeed be minimal.

  12. Seasonal variation of semidiurnal internal tides in the East/Japan Sea

    NASA Astrophysics Data System (ADS)

    Jeon, Chanhyung; Park, Jae-Hun; Varlamov, Sergey M.; Yoon, Jong-Hwan; Kim, Young Ho; Seo, Seongbong; Park, Young-Gyu; Min, Hong Sik; Lee, Jae Hak; Kim, Cheol-Ho

    2014-05-01

    The seasonal variation of semidiurnal internal tides in the East/Japan Sea was investigated using 25 month long output from a real-time ocean forecasting system. The z coordinate eddy-resolving high-resolution numerical model, called the RIAM ocean model, incorporates data assimilation that nudges temperature and salinity fields together with volume transport through the Korea Strait to produce realistic oceanic currents and stratification. In addition to atmospheric forcing, it includes tidal forcing of 16 major components along open boundaries. The model generates energetic semidiurnal internal tides around the northern entrance of the Korea Strait. Energy conversion from barotropic to baroclinic (internal) tides varies seasonally with maxima in September (ranging 0.48-0.52 GW) and minima in March (ranging 0.11-0.16 GW). This seasonal variation is induced by the seasonality in stratification near the southwestern East/Japan Sea. The propagation distance of the internal tides is associated with generation intensity and wavelength. From late summer to early winter, the semidiurnal internal tides travel relatively far from the generation region due to stratification changes; its energy dissipates less as a result of longer wavelengths. Our results suggest that spatiotemporal variation of internal-tide-induced mixing due to the seasonality in the generation, propagation, and dissipation of internal tides should be considered for a more realistic simulation of water masses and circulation in models of the East/Japan Sea.

  13. The science of space weather.

    PubMed

    Eastwood, Jonathan P

    2008-12-13

    The basic physics underpinning space weather is reviewed, beginning with a brief overview of the main causes of variability in the near-Earth space environment. Although many plasma phenomena contribute to space weather, one of the most important is magnetic reconnection, and recent cutting edge research in this field is reviewed. We then place this research in context by discussing a number of specific types of space weather in more detail. As society inexorably increases its dependence on space, the necessity of predicting and mitigating space weather will become ever more acute. This requires a deep understanding of the complexities inherent in the plasmas that fill space and has prompted the development of a new generation of scientific space missions at the international level.

  14. Late Holocene sea level variability and Atlantic Meridional Overturning Circulation

    USGS Publications Warehouse

    Cronin, Thomas M.; Farmer, Jesse R.; Marzen, R. E.; Thomas, E.; Varekamp, J.C.

    2014-01-01

    Pre-twentieth century sea level (SL) variability remains poorly understood due to limits of tide gauge records, low temporal resolution of tidal marsh records, and regional anomalies caused by dynamic ocean processes, notably multidecadal changes in Atlantic Meridional Overturning Circulation (AMOC). We examined SL and AMOC variability along the eastern United States over the last 2000 years, using a SL curve constructed from proxy sea surface temperature (SST) records from Chesapeake Bay, and twentieth century SL-sea surface temperature (SST) relations derived from tide gauges and instrumental SST. The SL curve shows multidecadal-scale variability (20–30 years) during the Medieval Climate Anomaly (MCA) and Little Ice Age (LIA), as well as the twentieth century. During these SL oscillations, short-term rates ranged from 2 to 4 mm yr−1, roughly similar to those of the last few decades. These oscillations likely represent internal modes of climate variability related to AMOC variability and originating at high latitudes, although the exact mechanisms remain unclear. Results imply that dynamic ocean changes, in addition to thermosteric, glacio-eustatic, or glacio-isostatic processes are an inherent part of SL variability in coastal regions, even during millennial-scale climate oscillations such as the MCA and LIA and should be factored into efforts that use tide gauges and tidal marsh sediments to understand global sea level rise.

  15. Eutrophication and warming-driven green tides (Ulva rigida) are predicted to increase under future climate change scenarios.

    PubMed

    Gao, Guang; Clare, Anthony S; Rose, Craig; Caldwell, Gary S

    2017-01-15

    The incidence and severity of extraordinary macroalgae blooms (green tides) are increasing. Here, climate change (ocean warming and acidification) impacts on life history and biochemical responses of a causative green tide species, Ulva rigida, were investigated under combinations of pH (7.95, 7.55, corresponding to lower and higher pCO 2 ), temperature (14, 18°C) and nitrate availability (6 and 150μmolL -1 ). The higher temperature accelerated the onset and magnitude of gamete settlement. Any two factor combination promoted germination and accelerated growth in young plants. The higher temperature increased reproduction, which increased further in combination with elevated pCO 2 or nitrate. Reproductive success was highest (64.4±5.1%) when the upper limits of all three variables were combined. Biochemically, more protein and lipid but less carbohydrate were synthesized under higher temperature and nitrate conditions. These results suggest that climate change may cause more severe green tides, particularly when eutrophication cannot be effectively controlled. Copyright © 2016 Elsevier Ltd. All rights reserved.

  16. Detecting the red tide based on remote sensing data in optically complex East China Sea

    NASA Astrophysics Data System (ADS)

    Xu, Xiaohui; Pan, Delu; Mao, Zhihua; Tao, Bangyi; Liu, Qiong

    2012-09-01

    Red tide not only destroys marine fishery production, deteriorates the marine environment, affects coastal tourist industry, but also causes human poison, even death by eating toxic seafood contaminated by red tide organisms. Remote sensing technology has the characteristics of large-scale, synchronized, rapid monitoring, so it is one of the most important and most effective means of red tide monitoring. This paper selects the high frequency red tides areas of the East China Sea as study area, MODIS/Aqua L2 data as the data source, analysis and compares the spectral differences in the red tide water bodies and non-red tide water bodies of many historical events. Based on the spectral differences, this paper develops the algorithm of Rrs555/Rrs488> 1.5 to extract the red tide information. Apply the algorithm on red tide event happened in the East China Sea on May 28, 2009 to extract the information of red tide, and found that the method can determine effectively the location of the occurrence of red tide; there is a good corresponding relationship between red tide extraction result and chlorophyll a concentration extracted by remote sensing, shows that these algorithm can determine effectively the location and extract the red tide information.

  17. Mapping nonlinear shallow-water tides: a look at the past and future

    NASA Astrophysics Data System (ADS)

    Andersen, Ole B.; Egbert, Gary D.; Erofeeva, Svetlana Y.; Ray, Richard D.

    2006-12-01

    Overtides and compound tides are generated by nonlinear mechanisms operative primarily in shallow waters. Their presence complicates tidal analysis owing to the multitude of new constituents and their possible frequency overlap with astronomical tides. The science of nonlinear tides was greatly advanced by the pioneering researches of Christian Le Provost who employed analytical theory, physical modeling, and numerical modeling in many extensive studies, especially of the tides of the English Channel. Le Provost’s complementary work with satellite altimetry motivates our attempts to merge these two interests. After a brief review, we describe initial steps toward the assimilation of altimetry into models of nonlinear tides via generalized inverse methods. A series of barotropic inverse solutions is computed for the M_4 tide over the northwest European Shelf. Future applications of altimetry to regions with fewer in situ measurements will require improved understanding of error covariance models because these control the tradeoffs between fitting hydrodynamics and data, a delicate issue in coastal regions. While M_4 can now be robustly determined along the Topex/Poseidon satellite ground tracks, many other compound tides face serious aliasing problems.

  18. Impact of tides in a baroclinic circulation model of the Adriatic Sea

    NASA Astrophysics Data System (ADS)

    Guarnieri, A.; Pinardi, N.; Oddo, P.; Bortoluzzi, G.; Ravaioli, M.

    2013-01-01

    AbstractThe impact of <span class="hlt">tides</span> in the circulation of the Adriatic Sea is investigated by means of a nested baroclinic numerical ocean model. <span class="hlt">Tides</span> are introduced using a modified Flather boundary condition at the open edge of the domain. The results show that tidal amplitudes and phases are reproduced correctly by the baroclinic model and tidal harmonic constants errors are comparable with those resulting from the most consolidated barotropic models. Numerical experiments were conducted to estimate and assess the impact of (i) the modified Flather lateral boundary condition; (ii) <span class="hlt">tides</span> on temperature, salinity, and stratification structures in the basin; and (iii) <span class="hlt">tides</span> on mixing and circulation in general. <span class="hlt">Tides</span> induce a different momentum advective component in the basin, which in turn produces a different distribution of water masses in the basin. <span class="hlt">Tides</span> impact on mixing and stratification in the River Po region (northwestern Adriatic) and induce semidiurnal fluctuations of salinity and temperature, in all four seasons for the former and summer alone for the latter. A clear presence of internal <span class="hlt">tides</span> was evidenced in the northern Adriatic Sea basin, corroborating previous findings.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2005SPIE.5794..415B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2005SPIE.5794..415B"><span>Spatio-temporal environmental data <span class="hlt">tide</span> corrections for reconnaissance operations</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Barbu, Costin; Avera, Will; Harris, Mike; Malpass, Kevyn</p> <p>2005-06-01</p> <p>Dynamic, accurate near-real time environmental data is critical to the success of the mine countermeasures operations. Bathymetric data acquired from the AQS-20 mine hunting sensor should be adjusted for local <span class="hlt">tide</span> variations related to the specific geographic area and time interval. This problem can be overcome by a spatio-temporal estimate of <span class="hlt">tide</span> corrections provided for the area and time of interest by the Naval Research Laboratory <span class="hlt">tide</span> prediction code PCTides. For each geographic position of the AQS-20 sonar, a <span class="hlt">tide</span> height relative to mean sea level is computed by interpolating the tidal information from the K - nearest neighbored stations for the corresponding time. The value is used to correct the measured depth generated by the AQS-20 sonar in that location to mean sea level for fusion with other bathymetric data products. It is argued that this paper provides a useful tool to the MCM decision factors during Mine Warfare operations.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016EGUGA..1812987B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016EGUGA..1812987B"><span>The Early-Warning System for incoming storm surge and <span class="hlt">tide</span> in the Republic of Mauritius</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Bogaard, Tom; de Lima Rego, Joao; Vatvani, Deepak; Virasami, Renganaden; Verlaan, Martin</p> <p>2016-04-01</p> <p>The Republic of Mauritius (ROM) is a group of islands in the South West of the Indian Ocean, consisting of the main islands of Mauritius, Rodrigues and Agalega and the archipelago of Saint Brandon. The ROM is particularly vulnerable to the adverse effects of climate change, especially in the coastal zone, where a convergence of accelerating sea level rise and increasing intensity of tropical cyclones is expected to result in considerable economic loss, humanitarian stresses, and environmental degradation. Storm surges and swell waves are expected to be aggravated through sea level rise and climate change effects on <span class="hlt">weather</span> patterns. Adaptation to increased vulnerability requires a re-evaluation of existing preparedness measures. The focus of this project is on more effective preparedness and issuing of alerts developing a fully-automated Early-Warning System for incoming storm surge and <span class="hlt">tide</span>, together with the Mauritius Meteorological Services and the National Disaster Risk Reduction and Management Centre (NDRRMC), such that coastal communities in Mauritius, Rodrigues and Agalega Islands are able to evacuate timely and safely in case of predicted extreme water levels. The Mauritius Early-Warning System for storm surge and <span class="hlt">tide</span> was implemented using software from Deltares' Open-Source and free software Community. A set of five depth-averaged Delft3D-FLOW hydrodynamic models are run every six-hours with a forecast horizon of three days, simulating water levels along the coast of the three main islands. Two regional models of horizontal resolution 5km force the three detailed models of 500m resolution; all models are forced at the surface by the 0.25° NOAA/GFS meteorological forecasts. In addition, our Wind-Enhancement Scheme is used to blend detailed cyclone track bulletin's info with the larger-scale Numerical <span class="hlt">Weather</span> Predictions. Measured data is retrieved near real-time from available Automatic <span class="hlt">Weather</span> Stations. All these workflows are managed by the operational</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_12");'>12</a></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li class="active"><span>14</span></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_14 --> <div id="page_15" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li class="active"><span>15</span></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="281"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017EGUGA..1912579V','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017EGUGA..1912579V"><span>Topographic imprint on chemical <span class="hlt">weathering</span> in deeply <span class="hlt">weathered</span> soil-mantled landscapes (southern Brazil)</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Vanacker, Veerle; Schoonejans, Jerome; Ameijeiras-Marino, Yolanda; Opfergelt, Sophie; Minella, Jean</p> <p>2017-04-01</p> <p>The regolith mantle is defined as the thin layer of unconsolidated material overlaying bedrock that contributes to shape the Earth's surface. The development of the regolith mantle in a landscape is the result of in-situ <span class="hlt">weathering</span>, atmospheric input and downhill transport of <span class="hlt">weathering</span> products. Bedrock <span class="hlt">weathering</span> - the physical and chemical transformations of rock to soil - contributes to the vertical development of the regolith layer through downward propagation of the <span class="hlt">weathering</span> front. Lateral transport of soil particles, aggregates and solutes by diffusive and concentrated particle and solute fluxes result in lateral redistribution of <span class="hlt">weathering</span> products over the hillslope. In this study, we aim to expand the empirical basis on long-term soil evolution at the landscape scale through a detailed study of soil <span class="hlt">weathering</span> in subtropical soils. Spatial <span class="hlt">variability</span> in chemical mass fluxes and <span class="hlt">weathering</span> intensity were studied along two toposequences with similar climate, lithology and vegetation but different slope morphology. This allowed us to isolate the topographic imprint on chemical <span class="hlt">weathering</span> and soil development. The toposequences have convexo-concave slope morphology, and eight regolith profiles were analysed involving the flat upslope, steep midslope and flat toeslope part. Our data show a clear topographic imprint on soil development. Along hillslope, the chemical <span class="hlt">weathering</span> intensity of the regolith profiles increases with distance from the crest. In contrast to the upslope positions, the soils in the basal concavities develop on in-situ and transported regolith. While the chemical <span class="hlt">weathering</span> extent on the slope convexities (the upslope profiles) is similar for the steep and gentle toposequence, there is a clear difference in the rate of increase of the chemical <span class="hlt">weathering</span> extent with distance from the crest. The increase of chemical <span class="hlt">weathering</span> extent along hillslope is highest for the steep toposequence, suggesting that topography enhances soil particle</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=1257557','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=1257557"><span>Overview of Aerosolized Florida Red <span class="hlt">Tide</span> Toxins: Exposures and Effects</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Fleming, Lora E.; Backer, Lorraine C.; Baden, Daniel G.</p> <p>2005-01-01</p> <p>Florida red <span class="hlt">tide</span> is caused by Karenia brevis, a dinoflagellate that periodically blooms, releasing its potent neurotoxin, brevetoxin, into the surrounding waters and air along the coast of the Gulf of Mexico. Exposure to Florida red <span class="hlt">tide</span> toxins has been associated with adverse human health effects and massive fish and marine mammal deaths. The articles in this mini-monograph describe the ongoing interdisciplinary and interagency research program that characterizes the exposures and health effects of aerosolized Florida red <span class="hlt">tide</span> toxins (brevetoxins). The interdisciplinary research program uses animal models and laboratory studies to develop hypotheses and apply these findings to in situ human exposures. Our ultimate goal is to develop appropriate prevention measures and medical interventions to mitigate or prevent adverse health effects from exposure to complex mixtures of aerosolized red <span class="hlt">tide</span> toxins. PMID:15866773</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/15866773','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/15866773"><span>Overview of aerosolized Florida red <span class="hlt">tide</span> toxins: exposures and effects.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Fleming, Lora E; Backer, Lorraine C; Baden, Daniel G</p> <p>2005-05-01</p> <p>Florida red <span class="hlt">tide</span> is caused by Karenia brevis, a dinoflagellate that periodically blooms, releasing its potent neurotoxin, brevetoxin, into the surrounding waters and air along the coast of the Gulf of Mexico. Exposure to Florida red <span class="hlt">tide</span> toxins has been associated with adverse human health effects and massive fish and marine mammal deaths. The articles in this mini-monograph describe the ongoing interdisciplinary and interagency research program that characterizes the exposures and health effects of aerosolized Florida red <span class="hlt">tide</span> toxins (brevetoxins). The interdisciplinary research program uses animal models and laboratory studies to develop hypotheses and apply these findings to in situ human exposures. Our ultimate goal is to develop appropriate prevention measures and medical interventions to mitigate or prevent adverse health effects from exposure to complex mixtures of aerosolized red <span class="hlt">tide</span> toxins.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/22165212','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/22165212"><span>[Temporal and spatial distribution of red <span class="hlt">tide</span> in Yangtze River Estuary and adjacent waters].</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Liu, Lu-San; Li, Zi-Cheng; Zhou, Juan; Zheng, Bing-Hui; Tang, Jing-Liang</p> <p>2011-09-01</p> <p>The events of red <span class="hlt">tide</span> were collected in Yangtze River Estuary and adjacent waters from 1972 to 2009. Based on geographic information system (GIS) analysis on the temporal and spatial distribution of red <span class="hlt">tide</span>, the distribution map was generated accordingly. The results show: (1) There are three red <span class="hlt">tide</span>-prone areas, which are outside the Yangtze River estuary and the eastern of Sheshan, Huaniaoshan-Shengshan-Gouqi, Zhoushan and the eastern of Zhujiajian. The red <span class="hlt">tide</span> occurred 174 times in total, in which there were 25 times covered the area was larger than 1 000 km2. After 2000, the frequency of red <span class="hlt">tide</span> were significantly increasing; (2) The frequent occurrence of red <span class="hlt">tide</span> was in May (51% of total occurrence) and June (20% of total occurrence); (3) In all of the red <span class="hlt">tide</span> plankton, the dominant species were Prorocentrum danghaiense, Skeletonema costatum, Prorocentrum dantatum, Nactiluca scientillans. The red <span class="hlt">tides</span> caused by these species were 38, 35, 15, 10 times separately.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=PIA10149&hterms=red+tide&qs=N%3D0%26Ntk%3DAll%26Ntx%3Dmode%2Bmatchall%26Ntt%3Dred%2Btide','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=PIA10149&hterms=red+tide&qs=N%3D0%26Ntk%3DAll%26Ntx%3Dmode%2Bmatchall%26Ntt%3Dred%2Btide"><span>Europa <span class="hlt">Tide</span> Movie</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p></p> <p>2007-01-01</p> <p><p/> [figure removed for brevity, see original site] Click on the image for Europa <span class="hlt">Tide</span> Movie <p/> In this movie Europa is seen in a cutaway view through two cycles of its 3.5 day orbit about the giant planet Jupiter. Like Earth, Europa is thought to have an iron core, a rocky mantle and a surface ocean of salty water. Unlike on Earth, however, this ocean is deep enough to cover the whole moon, and being far from the sun, the ocean surface is globally frozen over. Europa's orbit is eccentric, which means as it travels around Jupiter, large <span class="hlt">tides</span>, raised by Jupiter, rise and fall. Jupiter's position relative to Europa is also seen to librate, or wobble, with the same period. This tidal kneading causes frictional heating within Europa, much in the same way a paper clip bent back and forth can get hot to the touch, as illustrated by the red glow in the interior of Europa's rocky mantle and in the lower, warmer part of its ice shell. This tidal heating is what keeps Europa's ocean liquid and could prove critical to the survival of simple organisms within the ocean, if they exist.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012AGUFM.A41I0100D','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012AGUFM.A41I0100D"><span>Generation of Multivariate Surface <span class="hlt">Weather</span> Series with Use of the Stochastic <span class="hlt">Weather</span> Generator Linked to Regional Climate Model</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Dubrovsky, M.; Farda, A.; Huth, R.</p> <p>2012-12-01</p> <p>The regional-scale simulations of <span class="hlt">weather</span>-sensitive processes (e.g. hydrology, agriculture and forestry) for the present and/or future climate often require high resolution meteorological inputs in terms of the time series of selected surface <span class="hlt">weather</span> characteristics (typically temperature, precipitation, solar radiation, humidity, wind) for a set of stations or on a regular grid. As even the latest Global and Regional Climate Models (GCMs and RCMs) do not provide realistic representation of statistical structure of the surface <span class="hlt">weather</span>, the model outputs must be postprocessed (downscaled) to achieve the desired statistical structure of the <span class="hlt">weather</span> data before being used as an input to the follow-up simulation models. One of the downscaling approaches, which is employed also here, is based on a <span class="hlt">weather</span> generator (WG), which is calibrated using the observed <span class="hlt">weather</span> series and then modified (in case of simulations for the future climate) according to the GCM- or RCM-based climate change scenarios. The present contribution uses the parametric daily <span class="hlt">weather</span> generator M&Rfi to follow two aims: (1) Validation of the new simulations of the present climate (1961-1990) made by the ALADIN-Climate/CZ (v.2) Regional Climate Model at 25 km resolution. The WG parameters will be derived from the RCM-simulated surface <span class="hlt">weather</span> series and compared to those derived from observational data in the Czech meteorological stations. The set of WG parameters will include selected statistics of the surface temperature and precipitation (characteristics of the mean, <span class="hlt">variability</span>, interdiurnal <span class="hlt">variability</span> and extremes). (2) Testing a potential of RCM output for calibration of the WG for the ungauged locations. The methodology being examined will consist in using the WG, whose parameters are interpolated from the surrounding stations and then corrected based on a RCM-simulated spatial <span class="hlt">variability</span>. The quality of the <span class="hlt">weather</span> series produced by the WG calibrated in this way will be assessed in terms</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015EJPh...36f5012P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015EJPh...36f5012P"><span>Weight, gravitation, inertia, and <span class="hlt">tides</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Pujol, Olivier; Lagoute, Christophe; Pérez, José-Philippe</p> <p>2015-11-01</p> <p>This paper deals with the factors that influence the weight of an object near the Earth's surface. They are: (1) the Earth's gravitational force, (2) the centrifugal force due to the Earth's diurnal rotation, and (3) tidal forces due to the gravitational field of the Moon and Sun, and other solar system bodies to a lesser extent. Each of these three contributions is discussed and expressions are derived. The relationship between weight and gravitation is thus established in a direct and pedagogical manner readily understandable by undergraduate students. The analysis applies to the Newtonian limit of gravitation. The derivation is based on an experimental (or operational) definition of weight, and it is shown that it coincides with the Earth’s gravitational force modified by diurnal rotation around a polar axis and non-uniformity of external gravitational bodies (tidal term). Two examples illustrate and quantify these modifications, respectively the Eötvös effect and the oceanic <span class="hlt">tides</span>; tidal forces due to differential gravitation on a spacecraft and an asteroid are also proposed as examples. Considerations about inertia are also given and some comments are made about a widespread, yet confusing, explanation of <span class="hlt">tides</span> based on a centrifugal force. Finally, the expression of the potential energy of the <span class="hlt">tide</span>-generating force is established rigorously in the appendix.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/20379895','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/20379895"><span>Personal exposure to aerosolized red <span class="hlt">tide</span> toxins (brevetoxins).</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Cheng, Yung Sung; Zhou, Yue; Naar, Jerome; Irvin, C Mitch; Su, Wei-Chung; Fleming, Lora E; Kirkpatrick, Barbara; Pierce, Richard H; Backer, Lorraine C; Baden, Daniel G</p> <p>2010-06-01</p> <p>Florida red <span class="hlt">tides</span> occur annually in the Gulf of Mexico from blooms of the marine dinoflagellate, Karenia brevis, which produces highly potent natural polyether toxins, brevetoxins. Several epidemiologic studies have demonstrated that human exposure to red <span class="hlt">tide</span> aerosol could result in increased respiratory symptoms. Environmental monitoring of aerosolized brevetoxins was performed using a high-volume sampler taken hourly at fixed locations on Siesta Beach, Florida. Personal exposure was monitored using personal air samplers and taking nasal swab samples from the subjects who were instructed to spend 1 hr on Sarasota Beach during two sampling periods of an active Florida red <span class="hlt">tide</span> event in March 2005, and in May 2008 when there was no red <span class="hlt">tide</span>. Results showed that the aerosolized brevetoxins from the personal sampler were in modest agreement with the environmental concentration taken from a high-volume sampler. Analysis of nasal swab samples for brevetoxins demonstrated 68% positive samples in the March 2005 sampling period when air concentrations of brevetoxins were between 50 to 120 ng/m(3) measured with the high-volume sampler. No swab samples showed detectable levels of brevetoxins in the May 2008 study, when all personal samples were below the limit of detection. However, there were no statistical correlations between the amounts of brevetoxins detected in the swab samples with either the environmental or personal concentration. Results showed that the personal sample might provide an estimate of individual exposure level. Nasal swab samples showed that brevetoxins indeed were inhaled and deposited in the nasal passage during the March 2005 red <span class="hlt">tide</span> event.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19790013333','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19790013333"><span>High precision <span class="hlt">tide</span> spectroscopy. [using the superconducting gravimeter</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Goodkind, J. M.</p> <p>1978-01-01</p> <p>Diurnal and long period earth <span class="hlt">tides</span> were measured to high accuracy and precision with the superconducting gravimeter. The results provide new evidence on the geophysical questions which have been attacked through earth <span class="hlt">tide</span> measurements in the past. In addition, they raise new questions of potential interest. Slow fluctuations in gravity of order 10 micron gal over periods of 3 to 5 months were observed and are discussed.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://eric.ed.gov/?q=lunar&pg=7&id=EJ605726','ERIC'); return false;" href="https://eric.ed.gov/?q=lunar&pg=7&id=EJ605726"><span>The <span class="hlt">Tides</span>--A Neglected Topic.</span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Hartel, Hermann</p> <p>2000-01-01</p> <p>Finds that computer simulations can be used to visualize the processes involved with lunar <span class="hlt">tides</span>. Technology adds value, thus opening new paths for a more distinct analysis and increased learning results. (Author/CCM)</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19800016482','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19800016482"><span>Global Earth Response to Loading by Ocean <span class="hlt">Tide</span> Models</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Estes, R. H.; Strayer, J. M.</p> <p>1979-01-01</p> <p>Mathematical and programming techniques to numerically calculate Earth response to global semidiurnal and diurnal ocean <span class="hlt">tide</span> models were developed. Global vertical crustal deformations were evaluated for M sub 2, S sub 2, N sub 2, K sub 2, K sub 1, O sub 1, and P sub 1 ocean <span class="hlt">tide</span> loading, while horizontal deformations were evaluated for the M sub 2 tidal load. Tidal gravity calculations were performed for M sub 2 tidal loads, and strain tensor elements were evaluated for M sub 2 loads. The M sub 2 solution used for the ocean <span class="hlt">tide</span> included the effects of self-gravitation and crustal loading.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.fs.usda.gov/treesearch/pubs/38439','TREESEARCH'); return false;" href="https://www.fs.usda.gov/treesearch/pubs/38439"><span>A portable station for recording fire <span class="hlt">weather</span> data</span></a></p> <p><a target="_blank" href="http://www.fs.usda.gov/treesearch/">Treesearch</a></p> <p>John R. Murray; Clive M. Countryman</p> <p>1968-01-01</p> <p>A portable station for recording fire <span class="hlt">weather</span> data has been developed for use in wildland fires, prescribed burns, evaluating sites for fire <span class="hlt">weather</span> stations, and fire research. Housed in a mechanic's tool box, the station weighs about 60 pounds. One man can have it ready to operate in about 15 minutes. The unit can record five <span class="hlt">weather</span> <span class="hlt">variables</span>, but additional...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.fs.usda.gov/treesearch/pubs/44847','TREESEARCH'); return false;" href="https://www.fs.usda.gov/treesearch/pubs/44847"><span>Impacts of exotic mangroves and mangrove control on <span class="hlt">tide</span> pool fish assemblages</span></a></p> <p><a target="_blank" href="http://www.fs.usda.gov/treesearch/">Treesearch</a></p> <p>Richard A. MacKenzie; Cailtin L. Kryss</p> <p>2013-01-01</p> <p>Fish were sampled from <span class="hlt">tide</span> pools in Hawaii to determine how exotic mangroves Rhizophora mangle and the use of herbicides to chemically eradicate them are impacting <span class="hlt">tide</span> pool fish assemblages. Ecological parameters were compared among mangrove-invaded, native vegetated, and non-vegetated <span class="hlt">tide</span> pools before and after mangroves had been chemically...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017JGRC..12210156S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017JGRC..12210156S"><span>The Effect of Barotropic and Baroclinic <span class="hlt">Tides</span> on Coastal Stratification and Mixing</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Suanda, S. H.; Feddersen, F.; Kumar, N.</p> <p>2017-12-01</p> <p>The effects of barotropic and baroclinic <span class="hlt">tides</span> on subtidal stratification and vertical mixing are examined with high-resolution, three-dimensional numerical simulations of the Central Californian coastal upwelling region. A base simulation with realistic atmospheric and regional-scale boundary forcing but no <span class="hlt">tides</span> (NT) is compared to two simulations with the addition of predominantly barotropic local <span class="hlt">tides</span> (LT) and with combined barotropic and remotely generated, baroclinic <span class="hlt">tides</span> (WT) with ≈ 100 W m-1 onshore baroclinic energy flux. During a 10 day period of coastal upwelling when the domain volume-averaged temperature is similar in all three simulations, LT has little difference in subtidal temperature and stratification compared to NT. In contrast, the addition of remote baroclinic <span class="hlt">tides</span> (WT) reduces the subtidal continental shelf stratification up to 50% relative to NT. Idealized simulations to isolate barotropic and baroclinic effects demonstrate that within a parameter space of typical U.S. West Coast continental shelf slopes, barotropic tidal currents, incident energy flux, and subtidal stratification, the dissipating baroclinic <span class="hlt">tide</span> destroys stratification an order of magnitude faster than barotropic <span class="hlt">tides</span>. In WT, the modeled vertical temperature diffusivity at the top (base) of the bottom (surface) boundary layer is increased up to 20 times relative to NT. Therefore, the width of the inner-shelf (region of surface and bottom boundary layer overlap) is increased approximately 4 times relative to NT. The change in stratification due to dissipating baroclinic <span class="hlt">tides</span> is comparable to the magnitude of the observed seasonal cycle of stratification.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20000072440','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20000072440"><span>Constraints on Energy Dissipation in the Earth's Body <span class="hlt">Tide</span> From Satellite Tracking and Altimetry</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Ray, Richard D.; Eanes, Richard J.; Lemoine, Frank G.</p> <p>1992-01-01</p> <p>The phase lag by which the earth's body <span class="hlt">tide</span> follows the tidal potential is estimated for the principal lunar semidiurnal <span class="hlt">tide</span> M(sub 2). The estimate results from combining recent tidal solutions from satellite tracking data and from Topex/Poseidon satellite altimeter data. Each data type is sensitive to the body-<span class="hlt">tide</span> lag: gravitationally for the tracking data, geometrically for the altimetry. Allowance is made for the lunar atmospheric <span class="hlt">tide</span>. For the tidal potential Love number kappa(sub 2) we obtain a lag epsilon of 0.20 deg +/- 0.05 deg, implying an effective body-<span class="hlt">tide</span> Q of 280 and body-<span class="hlt">tide</span> energy dissipation of 110 +/- 25 gigawatts.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2006AGUFMIN22A..03K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2006AGUFMIN22A..03K"><span>A Tsunami-Focused <span class="hlt">Tide</span> Station Data Sharing Framework</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Kari, U. S.; Marra, J. J.; Weinstein, S. A.</p> <p>2006-12-01</p> <p>The Indian Ocean Tsunami of 26 December 2004 made it clear that information about <span class="hlt">tide</span> stations that could be used to support detection and warning (such as location, collection and transmission capabilities, operator identification) are insufficiently known or not readily accessible. Parties interested in addressing this problem united under the Pacific Region Data Integrated Data Enterprise (PRIDE), and in 2005 began a multiyear effort to develop a distributed metadata system describing <span class="hlt">tide</span> stations starting with pilot activities in a regional framework and focusing on tsunami detection and warning systems being developed by various agencies. First, a plain semantic description of the tsunami-focused <span class="hlt">tide</span> station metadata was developed. The semantic metadata description was, in turn, developed into a formal metadata schema championed by International Tsunami Information Centre (ITIC) as part of a larger effort to develop a prototype web service under the PRIDE program in 2005. Under the 2006 PRIDE program the formal metadata schema was then expanded to corral input parameters for the <span class="hlt">Tide</span>Tool application used by Pacific Tsunami Warning Center (PTWC) to drill down into wave activity at a <span class="hlt">tide</span> station that is located using a web service developed on this metadata schema. This effort contributed to formalization of web service dissemination of PTWC watch and warning tsunami bulletins. During this time, the data content and sharing issues embodied in this schema have been discussed at various forums. The result is that the various stakeholders have different data provider and user perspectives (semantic content) and also exchange formats (not limited to just XML). The challenge then, is not only to capture all data requirements, but also to have formal representation that is easily transformed into any specified format. The latest revision of the <span class="hlt">tide</span> gauge schema (Version 0.3), begins to address this challenge. It encompasses a broader range of provider and user</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.er.usgs.gov/publication/70190198','USGSPUBS'); return false;" href="https://pubs.er.usgs.gov/publication/70190198"><span><span class="hlt">Weather</span>-centric rangeland revegetation planning</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Hardegree, Stuart P.; Abatzoglou, John T.; Brunson, Mark W.; Germino, Matthew; Hegewisch, Katherine C.; Moffet, Corey A.; Pilliod, David S.; Roundy, Bruce A.; Boehm, Alex R.; Meredith, Gwendwr R.</p> <p>2018-01-01</p> <p>Invasive annual weeds negatively impact ecosystem services and pose a major conservation threat on semiarid rangelands throughout the western United States. Rehabilitation of these rangelands is challenging due to interannual climate and subseasonal <span class="hlt">weather</span> <span class="hlt">variability</span> that impacts seed germination, seedling survival and establishment, annual weed dynamics, wildfire frequency, and soil stability. Rehabilitation and restoration outcomes could be improved by adopting a <span class="hlt">weather</span>-centric approach that uses the full spectrum of available site-specific <span class="hlt">weather</span> information from historical observations, seasonal climate forecasts, and climate-change projections. Climate data can be used retrospectively to interpret success or failure of past seedings by describing seasonal and longer-term patterns of environmental <span class="hlt">variability</span> subsequent to planting. A more detailed evaluation of <span class="hlt">weather</span> impacts on site conditions may yield more flexible adaptive-management strategies for rangeland restoration and rehabilitation, as well as provide estimates of transition probabilities between desirable and undesirable vegetation states. Skillful seasonal climate forecasts could greatly improve the cost efficiency of management treatments by limiting revegetation activities to time periods where forecasts suggest higher probabilities of successful seedling establishment. Climate-change projections are key to the application of current environmental models for development of mitigation and adaptation strategies and for management practices that require a multidecadal planning horizon. Adoption of new <span class="hlt">weather</span> technology will require collaboration between land managers and revegetation specialists and modifications to the way we currently plan and conduct rangeland rehabilitation and restoration in the Intermountain West.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4833402','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4833402"><span>Risk in daily newspaper coverage of red <span class="hlt">tide</span> blooms in Southwest Florida</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Li, Zongchao; Garrison, Bruce; Ullmann, Steven G.; Kirkpatrick, Barbara; Fleming, Lora E.; Hoagland, Porter</p> <p>2016-01-01</p> <p>This study investigated newspaper coverage of Florida red <span class="hlt">tide</span> blooms in four metropolitan areas of Southwest Florida during a 25-year period, 1987-2012. We focused on how journalists framed red <span class="hlt">tide</span> stories with respect to environmental risk, health risk, and economic risk. We determined risk to be a key factor in this news coverage, being an aspect of coverage of red <span class="hlt">tide</span> itself in terms of environmental risk, tourism risk, and public health risk. The study found that red <span class="hlt">tide</span> news coverage is most often framed as an environmental story. PMID:27087790</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/27087790','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/27087790"><span>Risk in daily newspaper coverage of red <span class="hlt">tide</span> blooms in Southwest Florida.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Li, Zongchao; Garrison, Bruce; Ullmann, Steven G; Kirkpatrick, Barbara; Fleming, Lora E; Hoagland, Porter</p> <p></p> <p>This study investigated newspaper coverage of Florida red <span class="hlt">tide</span> blooms in four metropolitan areas of Southwest Florida during a 25-year period, 1987-2012. We focused on how journalists framed red <span class="hlt">tide</span> stories with respect to environmental risk, health risk, and economic risk. We determined risk to be a key factor in this news coverage, being an aspect of coverage of red <span class="hlt">tide</span> itself in terms of environmental risk, tourism risk, and public health risk. The study found that red <span class="hlt">tide</span> news coverage is most often framed as an environmental story.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015JGeod..89.1233D','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015JGeod..89.1233D"><span>Revisiting the pole <span class="hlt">tide</span> for and from satellite altimetry</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Desai, Shailen; Wahr, John; Beckley, Brian</p> <p>2015-12-01</p> <p>Satellite altimeter sea surface height observations include the geocentric displacements caused by the pole <span class="hlt">tide</span>, namely the response of the solid Earth and oceans to polar motion. Most users of these data remove these effects using a model that was developed more than 20 years ago. We describe two improvements to the pole <span class="hlt">tide</span> model for satellite altimeter measurements. Firstly, we recommend an approach that improves the model for the response of the oceans by including the effects of self-gravitation, loading, and mass conservation. Our recommended approach also specifically includes the previously ignored displacement of the solid Earth due to the load of the ocean response, and includes the effects of geocenter motion. Altogether, this improvement amplifies the modeled geocentric pole <span class="hlt">tide</span> by 15 %, or up to 2 mm of sea surface height displacement. We validate this improvement using two decades of satellite altimeter measurements. Secondly, we recommend that the altimetry pole <span class="hlt">tide</span> model exclude geocentric sea surface displacements resulting from the long-term drift in polar motion. The response to this particular component of polar motion requires a more rigorous approach than is used by conventional models. We show that erroneously including the response to this component of polar motion in the pole <span class="hlt">tide</span> model impacts interpretation of regional sea level rise by ± 0.25 mm/year.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li class="active"><span>15</span></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_15 --> <div id="page_16" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li class="active"><span>16</span></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="301"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016OcDyn..66..637G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016OcDyn..66..637G"><span>Tidal asymmetry in a funnel-shaped estuary with mixed semidiurnal <span class="hlt">tides</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Gong, Wenping; Schuttelaars, Henk; Zhang, Heng</p> <p>2016-05-01</p> <p>Different types of tidal asymmetry (see review of de Swart and Zimmerman Annu Rev Fluid Mech 41: 203-229, 2009) are examined in this study. We distinguish three types of tidal asymmetry: duration and magnitude differences between flood and ebb tidal flow, duration difference between the rising and falling <span class="hlt">tides</span>. For waterborne substance transport, the first two asymmetries are important while the last one is not. In this study, we take the Huangmaohai Estuary (HE), Pearl River Delta, China as an example to examine the spatio-temporal variations of the tidal asymmetry in a mixed semidiurnal tidal regime and to explain them by investigating the associated mechanisms. The methodology defining the tidal duration asymmetry and velocity skewness, proposed by Nidzieko (J Geophys Res 115: C08006. doi: <ExternalRef> <RefSource>10.1029/2009JC005864</RefSource> <RefTarget Address="10.1029/2009JC005864" TargetType="DOI"/> </ExternalRef>, 2010) and synthesized by Song et al. (J Geophys Res 116: C12007. doi: <ExternalRef> <RefSource>10.1029/2011JC007270</RefSource> <RefTarget Address="10.1029/2011JC007270" TargetType="DOI"/> </ExternalRef>, 2011), is utilized here and referred to as tidal duration asymmetry (TDA) and flow velocity asymmetry (FVA), respectively. The methodology is further used to quantify the flow duration asymmetry (FDA). A positive asymmetry means a shorter duration of low water slack for FDA, a shorter duration of the rising <span class="hlt">tide</span> for TDA, and a flood dominance for FVA and vice versa. The Regional Ocean Modeling System (ROMS) model is used to provide relatively long-term water elevation and velocity data and to conduct diagnostic experiments. In the HE, the main tidal constituents are diurnal <span class="hlt">tides</span> K 1, O 1 and semidiurnal <span class="hlt">tides</span> M 2 and S 2. The interaction among the diurnal and semidiurnal <span class="hlt">tides</span> generates a negative tidal asymmetry, while the interactions among semidiurnal <span class="hlt">tides</span> and their overtides or compound <span class="hlt">tides</span> result in a positive tidal asymmetry. The</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.er.usgs.gov/publication/70013654','USGSPUBS'); return false;" href="https://pubs.er.usgs.gov/publication/70013654"><span>FINITE ELEMENT MODEL FOR <span class="hlt">TIDES</span> AND CURRENTS WITH FIELD APPLICATIONS.</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Walters, Roy A.</p> <p>1988-01-01</p> <p>A finite element model, based upon the shallow water equations, is used to calculate tidal amplitudes and currents for two field-scale test problems. Because <span class="hlt">tides</span> are characterized by line spectra, the governing equations are subjected to harmonic decomposition. Thus the solution <span class="hlt">variables</span> are the real and imaginary parts of the amplitude of sea level and velocity rather than a time series of these <span class="hlt">variables</span>. The time series is recovered through synthesis. This scheme, coupled with a modified form of the governing equations, leads to high computational efficiency and freedom from excessive numerical noise. Two test-cases are presented. The first is a solution for eleven tidal constituents in the English Channel and southern North Sea, and three constituents are discussed. The second is an analysis of the frequency response and tidal harmonics for south San Francisco Bay.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20000085551','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20000085551"><span>Resonant Third-Degree Diurnal <span class="hlt">Tides</span> in the Seas Off Western Europe</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Ray, Richard D.; Smith, David E. (Technical Monitor)</p> <p>2000-01-01</p> <p>Third-degree diurnal <span class="hlt">tides</span> are estimated from long time series of sea level measurements at three North Atlantic <span class="hlt">tide</span> gauges. Although their amplitudes are only a few mm or less, their admittances are far larger than those of second-degree diurnal <span class="hlt">tides</span>, just as Cartwright discovered for the M(sub 1) constituent. The <span class="hlt">tides</span> are evidently resonantly enhanced owing to high spatial correlation between the third-degree spherical harmonic of the tidal potential and a near-diurnal oceanic normal mode that is most pronounced in the North Atlantic. By estimating the ocean tidal response across the diurnal band (5 tidal constituents plus nodal modulations), the period and Q of this mode and one nearby mode are estimated.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017JGRA..122.4571S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017JGRA..122.4571S"><span>Solar and lunar tidal <span class="hlt">variabilities</span> in GPS-TEC and geomagnetic field variations: Seasonal as well as during the sudden stratospheric warming of 2010</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Sridharan, S.</p> <p>2017-04-01</p> <p>The Global Positioning System (GPS) deduced total electron content (TEC) data at 15°N (geomagnetic), which is the northern crest region of equatorial ionization anomaly, are used to study solar and lunar tidal <span class="hlt">variabilities</span> during the years 2008 and 2009 and also during the 2009-2010 winter, when a major sudden stratospheric warming (SSW) event has occurred. The diurnal and semidiurnal tidal amplitudes show semiannual variation with maximum amplitudes during February-March and September-November, whereas terdiurnal <span class="hlt">tide</span> is larger during April-September. They show significant longitudinal <span class="hlt">variability</span> with larger (smaller) amplitudes over 250°E-150°E (200°E-250°E). Lunar semidiurnal tidal amplitudes show sporadic enhancements during northern winter months and negligible amplitudes during northern summer months. They also show notable longitudinal <span class="hlt">variabilities</span>. The solar migrating <span class="hlt">tides</span> DW1 and SW2 show semiannual variation with larger amplitudes during spring equinox months, whereas TW3 maximizes during northern summer. DW2 shows larger amplitudes during summer months. During the SSW, except TW3, the migrating <span class="hlt">tides</span> DW1 and SW2 show considerable enhancements. Among solar nonmigrating <span class="hlt">tides</span>, SW1, TW2, and DS0 show larger enhancements. Solar <span class="hlt">tides</span> in TEC and equatorial electrojet strength over Tirunelveli vary with the time scale of 60 days during October 2009-March 2010 similar to ozone mass mixing ratio at 10 hPa, and this confirms the vital role of ozone in tidal <span class="hlt">variabilities</span> in ionospheric parameters. Lunar tidal amplitudes in changes in horizontal component of geomagnetic field (ΔH) are larger over Tirunelveli, a station near dip equator. Solar semidiurnal <span class="hlt">tides</span> in ΔH have larger amplitudes than lunar <span class="hlt">tides</span> over polar stations, Mawson and Godhavn.<abstract type="synopsis"><title type="main">Plain Language SummaryIn this paper, the variations of solar and lunar <span class="hlt">tides</span> in a few ionospheric parameters during the years 2008 and 2009 and during a disturbed</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012AGUFMNH33A1665W','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012AGUFMNH33A1665W"><span><span class="hlt">TIDE</span> TOOL: Open-Source Sea-Level Monitoring Software for Tsunami Warning Systems</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Weinstein, S. A.; Kong, L. S.; Becker, N. C.; Wang, D.</p> <p>2012-12-01</p> <p>A tsunami warning center (TWC) typically decides to issue a tsunami warning bulletin when initial estimates of earthquake source parameters suggest it may be capable of generating a tsunami. A TWC, however, relies on sea-level data to provide prima facie evidence for the existence or non-existence of destructive tsunami waves and to constrain tsunami wave height forecast models. In the aftermath of the 2004 Sumatra disaster, the International Tsunami Information Center asked the Pacific Tsunami Warning Center (PTWC) to develop a platform-independent, easy-to-use software package to give nascent TWCs the ability to process WMO Global Telecommunications System (GTS) sea-level messages and to analyze the resulting sea-level curves (marigrams). In response PTWC developed <span class="hlt">TIDE</span> TOOL that has since steadily grown in sophistication to become PTWC's operational sea-level processing system. <span class="hlt">TIDE</span> TOOL has two main parts: a decoder that reads GTS sea-level message logs, and a graphical user interface (GUI) written in the open-source platform-independent graphical toolkit scripting language Tcl/Tk. This GUI consists of dynamic map-based clients that allow the user to select and analyze a single station or groups of stations by displaying their marigams in strip-chart or screen-tiled forms. <span class="hlt">TIDE</span> TOOL also includes detail maps of each station to show each station's geographical context and reverse tsunami travel time contours to each station. <span class="hlt">TIDE</span> TOOL can also be coupled to the GEOWARE™ TTT program to plot tsunami travel times and to indicate the expected tsunami arrival time on the marigrams. Because sea-level messages are structured in a rich variety of formats <span class="hlt">TIDE</span> TOOL includes a metadata file, COMP_META, that contains all of the information needed by <span class="hlt">TIDE</span> TOOL to decode sea-level data as well as basic information such as the geographical coordinates of each station. <span class="hlt">TIDE</span> TOOL can therefore continuously decode theses sea-level messages in real-time and display the time</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017AGUFM.C13G..07J','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017AGUFM.C13G..07J"><span>Modelling and parameterizing the influence of <span class="hlt">tides</span> on ice-shelf melt rates</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Jourdain, N.; Molines, J. M.; Le Sommer, J.; Mathiot, P.; de Lavergne, C.; Gurvan, M.; Durand, G.</p> <p>2017-12-01</p> <p>Significant Antarctic ice sheet thinning is observed in several sectors of Antarctica, in particular in the Amundsen Sea sector, where warm circumpolar deep waters affect basal melting. The later has the potential to trigger marine ice sheet instabilities, with an associated potential for rapid sea level rise. It is therefore crucial to simulate and understand the processes associated with ice-shelf melt rates. In particular, the absence of <span class="hlt">tides</span> representation in ocean models remains a caveat of numerous ocean hindcasts and climate projections. In the Amundsen Sea, <span class="hlt">tides</span> are relatively weak and the melt-induced circulation is stronger than the tidal circulation. Using a regional 1/12° ocean model of the Amundsen Sea, we nonetheless find that <span class="hlt">tides</span> can increase melt rates by up to 36% in some ice-shelf cavities. Among the processes that can possibly affect melt rates, the most important is an increased exchange at the ice/ocean interface resulting from the presence of strong tidal currents along the ice drafts. Approximately a third of this effect is compensated by a decrease in thermal forcing along the ice draft, which is related to an enhanced vertical mixing in the ocean interior in presence of <span class="hlt">tides</span>. Parameterizing the effect of <span class="hlt">tides</span> is an alternative to the representation of explicit <span class="hlt">tides</span> in an ocean model, and has the advantage not to require any filtering of ocean model outputs. We therefore explore different ways to parameterize the effects of <span class="hlt">tides</span> on ice shelf melt. First, we compare several methods to impose tidal velocities along the ice draft. We show that getting a realistic spatial distribution of tidal velocities in important, and can be deduced from the barotropic velocities of a <span class="hlt">tide</span> model. Then, we explore several aspects of parameterized tidal mixing to reproduce the <span class="hlt">tide</span>-induced decrease in thermal forcing along the ice drafts.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://files.eric.ed.gov/fulltext/ED226987.pdf','ERIC'); return false;" href="http://files.eric.ed.gov/fulltext/ED226987.pdf"><span><span class="hlt">Tides</span>. Marine Science Curriculum Aid No. 5. Sea Grant Report 80-2.</span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>McDonald, Judy</p> <p></p> <p>This manual, developed for use in Alaskan secondary schools, is one of a continuing series designed to provide basic information about the marine environment and Alaskan marine resources. The first part of the manual presents information about <span class="hlt">tides</span>, focusing on: the nature of <span class="hlt">tides</span>; cause of <span class="hlt">tides</span>; factors related to tidal movement; types of…</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018JOUC...17..219L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018JOUC...17..219L"><span>Plausible Effect of <span class="hlt">Weather</span> on Atlantic Meridional Overturning Circulation with a Coupled General Circulation Model</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Liu, Zedong; Wan, Xiuquan</p> <p>2018-04-01</p> <p>The Atlantic meridional overturning circulation (AMOC) is a vital component of the global ocean circulation and the heat engine of the climate system. Through the use of a coupled general circulation model, this study examines the role of synoptic systems on the AMOC and presents evidence that internally generated high-frequency, synoptic-scale <span class="hlt">weather</span> <span class="hlt">variability</span> in the atmosphere could play a significant role in maintaining the overall strength and <span class="hlt">variability</span> of the AMOC, thereby affecting climate <span class="hlt">variability</span> and change. Results of a novel coupling technique show that the strength and <span class="hlt">variability</span> of the AMOC are greatly reduced once the synoptic <span class="hlt">weather</span> <span class="hlt">variability</span> is suppressed in the coupled model. The strength and <span class="hlt">variability</span> of the AMOC are closely linked to deep convection events at high latitudes, which could be strongly affected by the <span class="hlt">weather</span> <span class="hlt">variability</span>. Our results imply that synoptic <span class="hlt">weather</span> systems are important in driving the AMOC and its <span class="hlt">variability</span>. Thus, interactions between atmospheric <span class="hlt">weather</span> <span class="hlt">variability</span> and AMOC may be an important feedback mechanism of the global climate system and need to be taken into consideration in future climate change studies.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015AGUFM.H53A1648S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015AGUFM.H53A1648S"><span>Appraisal of <span class="hlt">Weather</span> Research and Forecasting Model Downscaling of Hydro-meteorological <span class="hlt">Variables</span> and their Applicability for Discharge Prediction: Prognostic Approach for Ungauged Basin</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Srivastava, P. K.; Han, D.; Rico-Ramirez, M. A.; Bray, M.; Islam, T.; Petropoulos, G.; Gupta, M.</p> <p>2015-12-01</p> <p>Hydro-meteorological <span class="hlt">variables</span> such as Precipitation and Reference Evapotranspiration (ETo) are the most important <span class="hlt">variables</span> for discharge prediction. However, it is not always possible to get access to them from ground based measurements, particularly in ungauged catchments. The mesoscale model WRF (<span class="hlt">Weather</span> Research & Forecasting model) can be used for prediction of hydro-meteorological <span class="hlt">variables</span>. However, hydro-meteorologists would like to know how well the downscaled global data products are as compared to ground based measurements and whether it is possible to use the downscaled data for ungauged catchments. Even with gauged catchments, most of the stations have only rain and flow gauges installed. Measurements of other <span class="hlt">weather</span> hydro-meteorological <span class="hlt">variables</span> such as solar radiation, wind speed, air temperature, and dew point are usually missing and thus complicate the problems. In this study, for downscaling the global datasets, the WRF model is setup over the Brue catchment with three nested domains (D1, D2 and D3) of horizontal grid spacing of 81 km, 27 km and 9 km are used. The hydro-meteorological <span class="hlt">variables</span> are downscaled using the WRF model from the National Centers for Enviromental Prediction (NCEP) reanalysis datasets and subsequently used for the ETo estimation using the Penman Monteith equation. The analysis of <span class="hlt">weather</span> <span class="hlt">variables</span> and precipitation are compared against the ground based datasets, which indicate that the datasets are in agreement with the observed datasets for complete monitoring period as well as during the seasons except precipitation whose performance is poorer in comparison to the measured rainfall. After a comparison, the WRF estimated precipitation and ETo are then used as a input parameter in the Probability Distributed Model (PDM) for discharge prediction. The input data and model parameter sensitivity analysis and uncertainty estimation are also taken into account for the PDM calibration and prediction following the Generalised</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017IJBm...61.1805H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017IJBm...61.1805H"><span>Differences in the importance of <span class="hlt">weather</span> and <span class="hlt">weather</span>-based decisions among campers in Ontario parks (Canada)</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Hewer, Micah J.; Scott, Daniel J.; Gough, William A.</p> <p>2017-10-01</p> <p>Parks and protected areas represent an important resource for tourism in Canada, in which camping is a common recreational activity. The important relationship between <span class="hlt">weather</span> and climate with recreation and tourism has been widely acknowledged within the academic literature. Howbeit, the need for activity-specific assessments has been identified as an on-going need for future research in the field of tourism climatology. Furthermore, very little is known about the interrelationships between personal characteristics and socio-demographics with <span class="hlt">weather</span> preferences and behavioural thresholds. This study uses a stated climate preferences approach (survey responses) to explore differences in the importance of <span class="hlt">weather</span> and related <span class="hlt">weather</span>-based decisions among summer campers in Ontario parks. Statistically significant differences were found among campers for each of the four dependent <span class="hlt">variables</span> tested in this study. Physically active campers placed greater importance on <span class="hlt">weather</span> but were still more tolerant of adverse <span class="hlt">weather</span> conditions. Older campers placed greater importance on <span class="hlt">weather</span>. Campers travelling shorter distances placed greater importance on <span class="hlt">weather</span> and were more likely to leave the park early due to adverse <span class="hlt">weather</span>. Campers staying for longer periods of time were less likely to leave early due to <span class="hlt">weather</span> and were willing to endure longer durations of adverse <span class="hlt">weather</span> conditions. Beginner campers placed greater importance on <span class="hlt">weather</span>, were more likely to leave early due to <span class="hlt">weather</span> and recorded lower temporal <span class="hlt">weather</span> thresholds. The results of this study contribute to the study of tourism climatology by furthering understanding of how personal characteristics such as gender, age, activity selection, trip duration, distance travelled, travel experience and life cycles affect <span class="hlt">weather</span> preferences and decisions, focusing this time on recreational camping in a park tourism context.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/28493143','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/28493143"><span>Differences in the importance of <span class="hlt">weather</span> and <span class="hlt">weather</span>-based decisions among campers in Ontario parks (Canada).</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Hewer, Micah J; Scott, Daniel J; Gough, William A</p> <p>2017-10-01</p> <p>Parks and protected areas represent an important resource for tourism in Canada, in which camping is a common recreational activity. The important relationship between <span class="hlt">weather</span> and climate with recreation and tourism has been widely acknowledged within the academic literature. Howbeit, the need for activity-specific assessments has been identified as an on-going need for future research in the field of tourism climatology. Furthermore, very little is known about the interrelationships between personal characteristics and socio-demographics with <span class="hlt">weather</span> preferences and behavioural thresholds. This study uses a stated climate preferences approach (survey responses) to explore differences in the importance of <span class="hlt">weather</span> and related <span class="hlt">weather</span>-based decisions among summer campers in Ontario parks. Statistically significant differences were found among campers for each of the four dependent <span class="hlt">variables</span> tested in this study. Physically active campers placed greater importance on <span class="hlt">weather</span> but were still more tolerant of adverse <span class="hlt">weather</span> conditions. Older campers placed greater importance on <span class="hlt">weather</span>. Campers travelling shorter distances placed greater importance on <span class="hlt">weather</span> and were more likely to leave the park early due to adverse <span class="hlt">weather</span>. Campers staying for longer periods of time were less likely to leave early due to <span class="hlt">weather</span> and were willing to endure longer durations of adverse <span class="hlt">weather</span> conditions. Beginner campers placed greater importance on <span class="hlt">weather</span>, were more likely to leave early due to <span class="hlt">weather</span> and recorded lower temporal <span class="hlt">weather</span> thresholds. The results of this study contribute to the study of tourism climatology by furthering understanding of how personal characteristics such as gender, age, activity selection, trip duration, distance travelled, travel experience and life cycles affect <span class="hlt">weather</span> preferences and decisions, focusing this time on recreational camping in a park tourism context.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017AGUFMSA33A2579C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017AGUFMSA33A2579C"><span>Semidiurnal Solar <span class="hlt">Tide</span> during the Fall Transition in the Northern Hemisphere</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Conte, J. F.; Chau, J. L.; Laskar, F.; Stober, G.; Schmidt, H.</p> <p>2017-12-01</p> <p>We present an analysis of the semidiurnal solar <span class="hlt">tide</span> (S2) during the fall transition in the Northern Hemisphere mesosphere and lower thermosphere (MLT) region. The tidal information has been derived from wind measurements provided by meteor radars at Andenes (69°N) and Juliusruh (54°N). During the autumn, S2 is characterized by a sudden and pronounced decrease occurring around day 285, every year and at all height levels. The spring transition also shows a decrease of S2, but that progressively extends from lower to higher altitudes during an interval of 15 to 40 days whose starting date varies from one year to the next. Possible explanations for the differences observed between fall and spring time periods are investigated using Hamburg Model of the Neutral and Ionized Atmosphere (HAMMONIA) simulations of zonal and meridional winds, as well as ozone concentrations. Our results indicate that both, the westward propagating wave number 2 migrating <span class="hlt">tide</span> (SW2) and the westward propagating wave number 1 non-migrating <span class="hlt">tide</span> (SW1) decrease significantly during the fall, which results in a pronounced decrease of S2, as seen in the observations. During the spring, SW2 also decreases while SW1 remains approximately constant or slightly increases, resulting in a not so pronounced and more extended in time decrease of S2. SW2 and ozone concentrations do not show significant differences from one year to the next. SW1 on the other hand, presents considerable <span class="hlt">variability</span>, which suggests that its source might be connected to interaction with other waves, such as gravity and planetary waves.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/26936121','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/26936121"><span>Abiotic factors influencing biomass accumulation of green <span class="hlt">tide</span> causing Ulva spp. on Pyropia culture rafts in the Yellow Sea, China.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Keesing, John K; Liu, Dongyan; Shi, Yajun; Wang, Yujue</p> <p>2016-04-15</p> <p>Annually recurrent green-<span class="hlt">tides</span> in the Yellow Sea have been shown to result from direct disposal into the sea of fouling Ulva from Pyropia aquaculture. The role abiotic factors play in Ulva biomass accumulation on rafts was studied to find ways to mitigate this problem. Dissolved inorganic nitrogen (DIN) was very high at all sites, but the highest Ulva biomass was associated with the lowest DIN and anthropogenic N. Under luxuriant background nutrient conditions, <span class="hlt">variability</span> in temperature and periods of emersion, rather than pH, light and salinity determined Ulva biomass. Two dominant species of Ulva displayed differing tolerances to temperature and desiccation which helped explain why Ulva prolifera dominates floating green-<span class="hlt">tides</span>. Rather than trying to mitigate green-<span class="hlt">tides</span> only by reducing nutrient pollution, an earlier harvest of Pyropia in southern Jiangsu Province especially before temperatures increase greatly above 10°C during April, could reduce the biomass of U. prolifera disposed from rafts. Crown Copyright © 2016. Published by Elsevier Ltd. All rights reserved.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017AGUFMNG41A0115D','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017AGUFMNG41A0115D"><span>SPAGETTA: a Multi-Purpose Gridded Stochastic <span class="hlt">Weather</span> Generator</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Dubrovsky, M.; Huth, R.; Rotach, M. W.; Dabhi, H.</p> <p>2017-12-01</p> <p>SPAGETTA is a new multisite/gridded multivariate parametric stochastic <span class="hlt">weather</span> generator (WG). Site-specific precipitation occurrence and amount are modelled by Markov chain and Gamma distribution, the non-precipitation <span class="hlt">variables</span> are modelled by an autoregressive (AR) model conditioned on precipitation occurrence, and the spatial coherence of all <span class="hlt">variables</span> is modelled following the Wilks' (2009) approach. SPAGETTA may be run in two modes. Mode 1: it is run as a classical WG, which is calibrated using <span class="hlt">weather</span> series from multiple sites, and only then it may produce arbitrarily long synthetic series mimicking the spatial and temporal structure of the calibration data. To generate the <span class="hlt">weather</span> series representing the future climate, the WG parameters are modified according to the climate change scenario, typically derived from GCM or RCM simulations. Mode 2: the user provides only basic information (not necessarily to be realistic) on the temporal and spatial auto-correlation structure of the <span class="hlt">weather</span> <span class="hlt">variables</span> and their mean annual cycle; the generator itself derives the parameters of the underlying AR model, which produces the multi-site <span class="hlt">weather</span> series. Optionally, the user may add the spatially varying trend, which is superimposed to the synthetic series. The contribution consists of following parts: (a) Model of the WG. (b) Validation of WG in terms of the spatial temperature and precipitation characteristics, including characteristics of spatial hot/cold/dry/wet spells. (c) Results of the climate change impact experiment, in which the WG parameters representing the spatial and temporal <span class="hlt">variability</span> are modified using the climate change scenarios and the effect on the above spatial validation indices is analysed. In this experiment, the WG is calibrated using the E-OBS gridded daily <span class="hlt">weather</span> data for several European regions, and the climate change scenarios are derived from the selected RCM simulations (CORDEX database). (d) The second mode of operation will be</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/23002593','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/23002593"><span>[Analysis on characteristics of red <span class="hlt">tide</span> in Fujian coastal waters during the last 10 years].</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Li, Xue-Ding</p> <p>2012-07-01</p> <p>There were 161 red <span class="hlt">tide</span> events collected during the last 10 years from 2001 to 2010 in Fujian coastal waters. Comprehensive analysis was performed using statistical methods and the results indicated the following characteristics of the temporal and spatial distribution of red <span class="hlt">tide</span> in Fujian coastal waters: (1) Outbreaks of red <span class="hlt">tide</span> often occurred between April and September, and the peak period was in May and June. Most red <span class="hlt">tide</span> events lasted for 2 to 4 days, and the affected area was below 50 square kilometers. The first outbreak of red <span class="hlt">tide</span> tended to occur earlier in recent years, and the lasting time became longer. (2) There were 20 species of organisms causing the red <span class="hlt">tides</span> in Fujian coastal waters, among which 10 species were Bacillariophyta, 9 species were Dinophyta and 1 species was Protozoa. Prorocentrum donghaiense was the most frequent cause of red <span class="hlt">tides</span>, followed by Noctiluca scintillans, Skeletonema costatum and Chaetoceros sp.. The species caused red <span class="hlt">tides</span> obeyed the succession law and there were always new species involved. (2) In terms of spatial distribution, outbreaks of red <span class="hlt">tides</span> mainly occurred in the coastal waters of Ningde, Fuzhou and Xiamen. The species causing red <span class="hlt">tides</span> were Prorocentrum donghaiense and Noctiluca in the coastal waters in the north of Pingtan, Fujian Province, Skeletonema costatum and Chaetoceros in the coastal waters in the south of Pingtan, Fujian Province. The comprehensive analysis of the characteristics of red <span class="hlt">tides</span> during the last 10 years is expected to provide scientific and reasonable basis for the prevention, reduction and forecast of red <span class="hlt">tides</span> in Fujian coastal waters.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=20170005843&hterms=foster&qs=N%3D0%26Ntk%3DAuthor-Name%26Ntx%3Dmode%2Bmatchall%26Ntt%3Dfoster','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=20170005843&hterms=foster&qs=N%3D0%26Ntk%3DAuthor-Name%26Ntx%3Dmode%2Bmatchall%26Ntt%3Dfoster"><span>Future Nuisance Flooding at Boston Caused by Astronomical <span class="hlt">Tides</span> Alone</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Ray, Richard D.; Foster, Grant</p> <p>2016-01-01</p> <p>Sea level rise necessarily triggers more occurrences of minor, or nuisance, flooding events along coastlines, a fact well documented in recent studies. At some locations nuisance flooding can be brought about merely by high spring <span class="hlt">tides</span>, independent of storms, winds, or other atmospheric conditions. Analysis of observed water levels at Boston indicates that tidal flooding began to occur there in 2011 and will become more frequent in subsequent years. A compilation of all predicted nuisance-flooding events, induced by astronomical <span class="hlt">tides</span> alone, is presented through year 2050. The accuracy of the <span class="hlt">tide</span> prediction is improved when several unusual properties of Gulf of Maine <span class="hlt">tides</span>, including secular changes, are properly accounted for. Future mean sea-level rise at Boston cannot be predicted with comparable confidence, so two very different climate scenarios are adopted; both predict a large increase in the frequency and the magnitude of tidal flooding events.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016PApGe.173.3999S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016PApGe.173.3999S"><span>Tsunami hazard assessment in the Hudson River Estuary based on dynamic tsunami-<span class="hlt">tide</span> simulations</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Shelby, Michael; Grilli, Stéphan T.; Grilli, Annette R.</p> <p>2016-12-01</p> <p>-way coupling. Four levels of nested grids are used, from a 1 arc-min spherical coordinate grid in the deep ocean down to a 39-m Cartesian grid in the HRE. Bottom friction coefficients in the finer grids are calibrated for the <span class="hlt">tide</span> to achieve the local spatially averaged MHW level at high <span class="hlt">tide</span> in the HRE. Combined tsunami-<span class="hlt">tide</span> simulations are then performed for four phases of the <span class="hlt">tide</span> corresponding to each tsunami arriving at Sandy Hook (NJ): 1.5 h ahead, concurrent with, 1.5 h after, and 3 h after the local high <span class="hlt">tide</span>. These simulations are forced along the offshore boundary of the third-level grid by linearly superposing time series of surface elevation and horizontal currents of the calibrated <span class="hlt">tide</span> and each tsunami wave train; this is done in deep enough water for a linear superposition to be accurate. Combined tsunami-<span class="hlt">tide</span> simulations are then performed with FUNWAVE-TVD in this and the finest nested grids. Results show that, for the 3 PMTs, depending on the <span class="hlt">tide</span> phase, the dynamic simulations lead to no or to a slightly increased inundation in the HRE (by up to 0.15 m depending on location), and to larger currents than for the simulations over a static level; the CRT SMF proxy tsunami is the PMT leading to maximum inundation in the HRE. For all <span class="hlt">tide</span> phases, nonlinear interactions between <span class="hlt">tide</span> and tsunami currents modify the elevation, current, and celerity of tsunami wave trains, mostly in the shallower water areas of the HRE where bottom friction dominates, as compared to a linear superposition of wave elevations and currents. We note that, while dynamic simulations predict a slight increase in inundation, this increase may be on the same order as, or even less than sources of uncertainty in the modeling of tsunami sources, such as their initial water elevation, and in bottom friction and bathymetry used in tsunami grids. Nevertheless, results in this paper provide insight into the magnitude and spatial <span class="hlt">variability</span> of tsunami propagation and impact in the complex inland</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012EGUGA..1413219L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012EGUGA..1413219L"><span>Do GCM's predict the climate.... Or the low frequency <span class="hlt">weather</span>?</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Lovejoy, S.; Schertzer, D.; Varon, D.</p> <p>2012-04-01</p> <p>Over twenty-five years ago, a three-regime scaling model was proposed describing the statistical <span class="hlt">variability</span> of the atmosphere over time scales ranging from <span class="hlt">weather</span> scales out to ≈ 100 kyrs. Using modern in situ data reanalyses, monthly surface series (at 5ox5o), 8 "multiproxy" (yearly) series of the Northern hemisphere from 1500 - 1980, and GRIP and Vostok paleotemperatures at 5.2 and ≈ 100 year resolutions (over the past 91-420 kyrs), we refine the model and show how it can be understood with the help of new developments in nonlinear dynamics, especially multifractals and cascades. In a scaling range, mean fluctuations in state <span class="hlt">variables</span> such as temperature ΔT vary in power law manners ≈ Δt**H the where Δt is the duration. At small (<span class="hlt">weather</span>) scales the fluctuation exponents are generally H>0; they grow with scale (Δt). At longer scales Δt >τw (≈ 10 days) H changes sign, the fluctuations decrease with scale; this is the low <span class="hlt">variability</span>, "low frequency <span class="hlt">weather</span>" regime. In this regime, the spectrum is a relatively flat "plateau", it's <span class="hlt">variability</span> is low, stable, corresponding to our usual idea of "long term <span class="hlt">weather</span> statistics". Finally for longer times, Δt>τc ≈ 10 - 100 years, once again H>0, so that the <span class="hlt">variability</span> increases with scale: the true climate regime. These scaling regimes allow us to objectively define the <span class="hlt">weather</span> as fluctuations over periods <τw, to define "climate states" as fluctuations at scale τc and then "climate change" as the fluctuations at longer periods (Δt>τc). We show that the intermediate low frequency <span class="hlt">weather</span> regime is the result of the <span class="hlt">weather</span> regime undergoing a "dimensional transition": at temporal scales longer than the typical lifetime of planetary structures (τw), the spatial degrees of freedom are rapidly quenched so that only the temporal degrees of freedom are important. This low frequency <span class="hlt">weather</span> regime has statistical properties well reproduced not only by stochastic cascade models of <span class="hlt">weather</span>, but also by</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20030102174','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20030102174"><span>Mesospheric Non-Migrating <span class="hlt">Tides</span> Generated With Planetary Waves: II Influence of Gravity Waves</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Mayr, H. G.; Mengel, J. G.; Talaat, E. L.; Porter, H. S.; Chan, K. L.</p> <p>2003-01-01</p> <p>We demonstrated that, in our model, non-linear interactions between planetary waves (PW) and migrating <span class="hlt">tides</span> could generate in the upper mesosphere non-migrating <span class="hlt">tides</span> with amplitudes comparable to those observed. The Numerical Spectral Model (NSM) we employ incorporates Hines Doppler Spread Parameterization for small-scale gravity waves (GW), which affect in numerous ways the dynamics of the mesosphere. The latitudinal (seasonal) reversals in the temperature and zonal circulation, which are largely caused by GWs (Lindzen, 198l), filter the PWs and contribute to the instabilities that generate the PWs. The PWs in turn are amplified by the momentum deposition of upward propagating GWs, as are the migrating <span class="hlt">tides</span>. The GWs thus affect significantly the migrating <span class="hlt">tides</span> and PWs, the building blocks of non-migrating <span class="hlt">tides</span>. In the present paper, we demonstrate that GW filtering also contributes to the non-linear coupling between PWs and <span class="hlt">tides</span>. Two computer experiments are presented to make this point. In one, we simply turn off the GW source to show the effect. In the second case, we demonstrate the effect by selectively suppressing the momentum source for the m = 0 non-migrating <span class="hlt">tides</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015APS..DFDM31006M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015APS..DFDM31006M"><span>Simultaneous generation and scattering of internal <span class="hlt">tides</span> by ocean floor topography</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Mathur, Manikandan</p> <p>2015-11-01</p> <p>Internal waves play a significant role in the global energy budget of the ocean, with internal <span class="hlt">tides</span> potentially contributing to the conversion of a large amount of mechanical energy into heat in the deep ocean. Several studies in the past decade have investigated internal <span class="hlt">tide</span> generation and internal <span class="hlt">tide</span> scattering by ocean floor topography, but by treating them as two separate, independent processes. In this talk, we use the recently developed Green function model (Mathur et al., J. Geophys. Res. Oceans, 119, 2165-2182, 2014), sans the WKB approximation, to quantify the extent to which internal <span class="hlt">tide</span> generation (scattering) that results from barotropic (baroclinic) forcing on small- and large-scale topography in uniform and nonuniform stratifications is modified by the presence of a background baroclinic (barotropic) <span class="hlt">tide</span>. Results on idealized topography, stratification and forcing will first be presented, followed by a discussion on the relevance of our studies in the real ocean scenario. The author thanks the Ministry of Earth Sciences, Government of India for financial support under the Monsoon Mission Grant MM/2014/IND-002.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li class="active"><span>16</span></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_16 --> <div id="page_17" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li class="active"><span>17</span></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="321"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018OcDyn.tmp...57W','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018OcDyn.tmp...57W"><span>Experimental investigation of internal <span class="hlt">tides</span> generated by finite-height topography</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Wang, Shuya; Chen, Xu; Wang, Jinhu; Meng, Jing</p> <p>2018-06-01</p> <p>Internal <span class="hlt">tides</span> generated by finite-height topography are investigated in the laboratory, and the particle image velocimetry (PIV) technique is applied to measure the velocity fields. The energy, energy flux, and vertical mode structure of the internal <span class="hlt">tides</span> are calculated and analyzed. The experimental results indicate that the strength of the wave field is mainly affected by the normalized topography height. The rays radiated from the taller topography are wider than those radiated from the lower topography. Both the experimental and theoretical results indicate that the normalized energy and energy flux of the internal <span class="hlt">tides</span> are mainly determined by the normalized topography height, and the increase of the two quantities follows a quadratic function, and they almost remain unchanged with different normalized frequencies except for higher frequency. The percentage of energy for mode-1 and mode-2 internal <span class="hlt">tides</span> is determined not only by frequency but also by topography height. In addition, an "inherent normalized frequency" is observed in the experiment, at which the percentage of energy for mode 1 and mode 2 does not vary with topography height. The decay rate of internal <span class="hlt">tide</span> energy in the near field and far field is also estimated, with average values of 36.5 and 7.5%, respectively.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016AGUFMOS23A1984K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016AGUFMOS23A1984K"><span>Effect of <span class="hlt">Tide</span> Elevation on Extratropical Storm Surge in Northwest Europe</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Keshtpoor, M.; Carnacina, I.; Yablonsky, R. M.</p> <p>2016-12-01</p> <p>Extratropical cyclones (ETCs) are the major storm surge-generating meteorological events in northwest Europe. The total water level increase induced by these ETCs is significantly influenced by the local tidal range, which exceeds 8 meters along the southwestern UK coastline. In particular, a surge-generating ETC during high <span class="hlt">tide</span> may put coastal assets and infrastructure in risk. Also, during low <span class="hlt">tide</span>, the risk of surge induced by extreme ETC events is diminished. Here, the effect of tidal elevation on storm surge is investigated at 196 <span class="hlt">tide</span> gauges in northwest Europe. A numerical, hydrodynamic model was developed using Delft3D-FM framework to simulate the coastal hydrodynamics during ETCs. Then, 1750 historical events were simulated to investigate the pattern of coastal inundation. Results suggest that in areas with a large tidal range ( 8 meters) and during the time period surrounding high or low <span class="hlt">tide</span>, the pattern of coastal hydrodynamics is governed by <span class="hlt">tide</span> and not storm surge. This result is most evident near the English Channel and Bristol Channel, where low frequency maximum water levels are observed when storm surge is combined with high <span class="hlt">tide</span>. In contrast, near the tidal phase reversal, coastal hydrodynamics responds primarily to the storm surge, and low frequency maximum water elevation largely depends on the surge. In the areas with a small tidal range, ETC strength determines the pattern of coastal inundation.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017ESD.....8.1223G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017ESD.....8.1223G"><span>Interannual <span class="hlt">variability</span> of mean sea level and its sensitivity to wind climate in an inter-tidal basin</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Gerkema, Theo; Duran-Matute, Matias</p> <p>2017-12-01</p> <p>The relationship between the annual wind records from a <span class="hlt">weather</span> station and annual mean sea level in an inter-tidal basin, the Dutch Wadden Sea, is examined. Recent, homogeneous wind records are used, covering the past 2 decades. It is demonstrated that even such a relatively short record is sufficient for finding a convincing relationship. The interannual <span class="hlt">variability</span> of mean sea level is largely explained by the west-east component of the net wind energy, with some further improvement if one also includes the south-north component and the annual mean atmospheric pressure. Using measured data from a <span class="hlt">weather</span> station is found to give a slight improvement over reanalysis data, but for both the correlation between annual mean sea level and wind energy in the west-east direction is high. For different <span class="hlt">tide</span> gauge stations in the Dutch Wadden Sea and along the coast, we find the same qualitative characteristics, but even within this small region, different locations show a different sensitivity of annual mean sea level to wind direction. Correcting observed values of annual mean level for meteorological factors reduces the margin of error (expressed as 95 % confidence interval) by more than a factor of 4 in the trends of the 20-year sea level record. Supplementary data from a numerical hydrodynamical model are used to illustrate the regional <span class="hlt">variability</span> in annual mean sea level and its interannual <span class="hlt">variability</span> at a high spatial resolution. This study implies that climatic changes in the strength of winds from a specific direction may affect local annual mean sea level quite significantly.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2011CSR....31..282C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2011CSR....31..282C"><span>Short-term variations in mesozooplankton, ichthyoplankton, and nutrients associated with semi-diurnal <span class="hlt">tides</span> in a patagonian Gulf</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Castro, L. R.; Cáceres, M. A.; Silva, N.; Muñoz, M. I.; León, R.; Landaeta, M. F.; Soto-Mendoza, S.</p> <p>2011-03-01</p> <p>The relationships between the distribution of different zooplankton and ichthyoplankton stages and physical and chemical <span class="hlt">variables</span> were studied using samples and data (CTD profiles, ADCP and current meter measurements, nutrients, mesozooplankton, ichthyoplankton) obtained from different strata during two 24-h cycles at two oceanographic stations in a Chilean Patagonian gulf during the CIMAR 10-Fiordos cruise (November, 2004). A station located at the Chacao Channel was dominated by tidal mixing and small increments in surface stratification during high <span class="hlt">tides</span>, leading to decreased nutrient availability. This agreed with short periods of increased phytoplankton abundance during slack waters at the end of flood currents. Increases in larval density for all zooplankton and ichthyoplankton taxa corresponded to the flooding phases of the tidal cycle. When the larval density data were fit to a sinusoidal model, the regression coefficients were high, suggesting that <span class="hlt">tides</span> are important features that modulate short-term variations in plankton abundance. All larvae did not vary synchronously with the tidal phase; rather, time lags were observed among species. The abundances of older individuals of the copepodite Rhincalanus nasutus and all zoea stages of the squat lobster Munida gregaria increased during night flood <span class="hlt">tides</span>, whereas younger stages increased during daytime flood <span class="hlt">tides</span>. At a station located at the Queullin Pass, which was dominated by vertical stratification patterns, the variations in peak larval density were better fitted to the semi-diurnal sea level fluctuations. Other evidence indicated internal <span class="hlt">tides</span> below the pycnocline, which could promote larval transport in deeper layers. In the overall picture that emerges from this study, planktonic organisms from different habitats and phylogenetic origins seem to respond to the local tidal regimes. In some cases, this response might be beneficial, transporting these individuals inshore to areas that are rich in</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19790022736','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19790022736"><span>M2, S2, K1 models of the global ocean <span class="hlt">tide</span></span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Parke, M. E.; Hendershott, M. C.</p> <p>1979-01-01</p> <p>Ocean tidal signals appear in many geophysical measurements. Geophysicists need realistic tidal models to aid in interpretation of their data. Because of the closeness to resonance of dissipationless ocean <span class="hlt">tides</span>, it is difficult for numerical models to correctly represent the actual open ocean <span class="hlt">tide</span>. As an approximate solution to this problem, test functions derived by solving Laplace's Tidal Equations with ocean loading and self gravitation are used as a basis for least squares dynamic interpolation of coastal and island tidal data for the constituents M2, S2, and Kl. The resulting representations of the global <span class="hlt">tide</span> are stable over at least a ?5% variation in the mean depth of the model basin, and they conserve mass. Maps of the geocentric <span class="hlt">tide</span>, the induced free space potential, the induced vertical component of the solid earth <span class="hlt">tide</span>, and the induced vertical component of the gravitational field for each contituent are presented.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19870034097&hterms=Paradox+value&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D20%26Ntt%3DParadox%2Bvalue','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19870034097&hterms=Paradox+value&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D20%26Ntt%3DParadox%2Bvalue"><span>Another look at North Sea pole <span class="hlt">tide</span> dynamics</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Dickman, S. R.; Preisig, J. R.</p> <p>1986-01-01</p> <p>The mechanism proposed by Wunsch (1974) to explain pole <span class="hlt">tide</span> observations in the North Sea is evaluated. Wunsch's equations governing pole <span class="hlt">tide</span> in the North Sea are presented, and solutions for correcting the depth, stream function, and deviation of the tidal height from the equilibrium values are described. The similarity between the Stokes paradox and the tidal equations of the North Sea, and the need for inclusion of inertial terms in the tidal equations are discussed.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20120009181','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20120009181"><span>Climate <span class="hlt">Variability</span> and <span class="hlt">Weather</span> Extremes: Model-Simulated and Historical Data. Chapter 9</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Schubert, Siegfried D.; Lim, Young-Kwon</p> <p>2012-01-01</p> <p>Extremes in <span class="hlt">weather</span> and climate encompass a wide array of phenomena including tropical storms, mesoscale convective systems, snowstorms, floods, heat waves, and drought. Understanding how such extremes might change in the future requires an understanding of their past behavior including their connections to large-scale climate <span class="hlt">variability</span> and trends. Previous studies suggest that the most robust findings concerning changes in short-term extremes are those that can be most directly (though not completely) tied to the increase in the global mean temperatures. These include the findings that (IPCC 2007): There has been a widespread reduction in the number of frost days in mid-latitude regions in recent decades, an increase in the number of warm extremes, particularly warm nights, and a reduction in the number of cold extremes, particularly cold nights. For North America in particular (CCSP SAP 3.3, 2008): There are fewer unusually cold days during the last few decades. The last 10 years have seen a lower number of severe cold waves than for any other 10-year period in the historical record that dates back to 1895. There has been a decrease in the number of frost days and a lengthening of the frost-free season, particularly in the western part of North America. Other aspects of extremes such as the changes in storminess have a less clear signature of long term change, with considerable interannual, and decadal <span class="hlt">variability</span> that can obscure any climate change signal. Nevertheless, regarding extratropical storms (CCSP SAP 3.3, 2008): The balance of evidence suggests that there has been a northward shift in the tracks of strong low pressure systems (storms) in both the North Atlantic and North Pacific basins. For North America: Regional analyses suggest that there has been a decrease in snowstorms in the South and lower Midwest of the United States, and an increase in snowstorms in the upper Midwest and Northeast. Despite the progress already made, our understanding of the</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015AGUFM.P13A2121T','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015AGUFM.P13A2121T"><span>Librations and <span class="hlt">tides</span> of icy satellites: model comparison for Enceladus</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Trinh, A.; Van Hoolst, T.; Baland, R. M.; Beuthe, M.; Rivoldini, A.; Dehant, V. M. A.</p> <p>2015-12-01</p> <p>The latest measurements of the librations of Enceladus suggest that it could have a global subsurface ocean or a non-hydrostatic core (Thomas et al. 2014). Further observations should constrain the properties of the ice shell, and similar insights are expected from future investigation of Europa and Ganymede.Detailed models of the librations and <span class="hlt">tides</span> are therefore required to properly interpret these measurements in terms of interior structure. Here we compare the `classical', separate <span class="hlt">tide</span> and libration models (where spherical symmetry is assumed to compute the <span class="hlt">tides</span>, Van Hoolst et al. 2013) with our combined <span class="hlt">tide</span>+libration model (Trinh et al. 2013), both extended to account for non-hydrostatic structure.Even with a global ocean, different mechanisms act to prevent Enceladus's shell from moving independently from the rest. Among those, pressure coupling across the flattened boundaries of the ocean requires special care if the shape is not fully relaxed. We discuss how it should be modelled in the classical approach to be consistent with the combined model.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/15476839','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/15476839"><span>Natural turbidity <span class="hlt">variability</span> and <span class="hlt">weather</span> forecasts in risk management of anthropogenic sediment discharge near sensitive environments.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Orpin, Alan R; Ridd, Peter V; Thomas, Séverine; Anthony, Kenneth R N; Marshall, Paul; Oliver, Jamie</p> <p>2004-10-01</p> <p>Coastal development activities can cause local increases in turbidity and sedimentation. This study characterises the spatial and temporal <span class="hlt">variability</span> of turbidity near an inshore fringing coral reef in the central Great Barrier Reef, under a wide range of natural conditions. Based on the observed natural <span class="hlt">variability</span>, we outline a risk management scheme to minimise the impact of construction-related turbidity increases. Comparison of control and impact sites proved unusable for real-time management of turbidity risks. Instead, we suggest using one standard deviation from ambient conditions as a possible conservative upper limit of an acceptable projected increase in turbidity. In addition, the use of regional <span class="hlt">weather</span> forecast as a proxy for natural turbidity is assessed. This approach is simple and cheap but also has limitations in very rough conditions, when an anthropogenic turbidity increase could prove fatal to corals that are already stressed under natural conditions.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20110023001','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20110023001"><span>Model of Semidiurnal Pseudo <span class="hlt">Tide</span> in the High-Latitude Upper Mesosphere</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Talaat, E. R.; Mayr, H. G.</p> <p>2011-01-01</p> <p>We present numerical results for the m = 1 meridional winds of semi diurnal oscillations in the high-latitude upper mesosphere, which are generated in the Numerical Spectral Model (NSM) without solar excitations of the <span class="hlt">tides</span>. Identified with heuristic computer runs, the pseudo <span class="hlt">tides</span> attain amplitudes that are, at times, as large as the non-migrating <span class="hlt">tides</span> produced with standard solar forcing. Under the influence of parameterized gravity waves, the nonlinear NSM generates internal oscillations like the quasi-biennial oscillation, that are produced with periods favored by the dynamical properties of the system. The Coriolis force would favor at polar latitudes the excitation of the 12-hour periodicity. This oscillation may help explain the large non-migrating semidiurnal <span class="hlt">tides</span> that are observed in the region with ground-based and satellite measurements.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.er.usgs.gov/publication/70040681','USGSPUBS'); return false;" href="https://pubs.er.usgs.gov/publication/70040681"><span>Metal stable isotopes in <span class="hlt">weathering</span> and hydrology: Chapter 10</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Bullen, Thomas D.; Holland, Heinrich; Turekian, K.</p> <p>2014-01-01</p> <p>This chapter highlights some of the major developments in the understanding of the causes of metal stable isotope compositional <span class="hlt">variability</span> in and isotope fractionation between natural materials and provides numerous examples of how that understanding is providing new insights into <span class="hlt">weathering</span> and hydrology. At this stage, our knowledge of causes of stable isotope compositional <span class="hlt">variability</span> among natural materials is greatest for the metals lithium, magnesium, calcium, and iron, the isotopes of which have already provided important information on <span class="hlt">weathering</span> and hydrological processes. Stable isotope compositional <span class="hlt">variability</span> for other metals such as strontium, copper, zinc, chromium, barium, molybdenum, mercury, cadmium, and nickel has been demonstrated but is only beginning to be applied to questions related to <span class="hlt">weathering</span> and hydrology, and several research groups are currently exploring the potential. And then there are other metals such as titanium, vanadium, rhenium, and tungsten that have yet to be explored for <span class="hlt">variability</span> of stable isotope composition in natural materials, but which may hold untold surprises in their utility. This impressive list of metals having either demonstrated or potential stable isotope signals that could be used to address important unsolved questions related to <span class="hlt">weathering</span> and hydrology, constitutes a powerful toolbox that will be increasingly utilized in the coming decades.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.fs.usda.gov/treesearch/pubs/39353','TREESEARCH'); return false;" href="https://www.fs.usda.gov/treesearch/pubs/39353"><span>Simulating spatial and temporally related fire <span class="hlt">weather</span></span></a></p> <p><a target="_blank" href="http://www.fs.usda.gov/treesearch/">Treesearch</a></p> <p>Isaac C. Grenfell; Mark Finney; Matt Jolly</p> <p>2010-01-01</p> <p>Use of fire behavior models has assumed an increasingly important role for managers of wildfire incidents to make strategic decisions. For fire risk assessments and danger rating at very large spatial scales, these models depend on fire <span class="hlt">weather</span> <span class="hlt">variables</span> or fire danger indices. Here, we describe a method to simulate fire <span class="hlt">weather</span> at a national scale that captures the...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016AGUFM.P51B2136B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016AGUFM.P51B2136B"><span>Subsurface Ocean <span class="hlt">Tides</span> in Enceladus and Other Icy Moons</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Beuthe, M.</p> <p>2016-12-01</p> <p>Could tidal dissipation within Enceladus' subsurface ocean account for the observed heat flow? Earthlike models of dynamical <span class="hlt">tides</span> give no definitive answer because they neglect the influence of the crust. I propose here the first model of dissipative <span class="hlt">tides</span> in a subsurface ocean, by combining the Laplace Tidal Equations with the membrane approach. For the first time, it is possible to compute tidal dissipation rates within the crust, ocean, and mantle in one go. I show that oceanic dissipation is strongly reduced by the crustal constraint, and thus contributes little to Enceladus' present heat budget. Tidal resonances could have played a role in a forming or freezing ocean less than 100 meters deep. The model is general: it applies to all icy satellites with a thin crust and a shallow or stratified ocean. Scaling rules relate the resonances and dissipation rate of a subsurface ocean to the ones of a surface ocean. If the ocean has low viscosity, the westward obliquity <span class="hlt">tide</span> does not move the crust. Therefore, crustal dissipation due to dynamical obliquity <span class="hlt">tides</span> can differ from the static prediction by up to a factor of two.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/18600196','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/18600196"><span>Illness associated with red <span class="hlt">tide</span>--Nassau County, Florida, 2007.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p></p> <p>2008-07-04</p> <p>A "red <span class="hlt">tide</span>" is a harmful algal bloom that occurs when toxic, microscopic algae in seawater proliferate to a higher-than-normal concentration (i.e., bloom), often discoloring the water red, brown, green, or yellow. Red <span class="hlt">tides</span> can kill fish, birds, and marine mammals and cause illness in humans. Florida red <span class="hlt">tide</span> is caused by the dinoflagellate Karenia brevis, which produces toxins called brevetoxins and is most commonly found in the Gulf of Mexico; however, K. brevis blooms also can occur along the Atlantic coast. On September 25, 2007, a cluster of respiratory illnesses was reported to the Nassau County Health Department (NCHD) in northeastern Florida. All of the ill persons were employed at a beach restoration worksite by a dredging company operating at Fernandina Beach; they reported symptoms of eye or respiratory irritation (e.g., coughing, sneezing, sniffling, and throat irritation). NCHD and the Florida Department of Health promptly conducted epidemiologic and environmental investigations and determined the illnesses likely were associated with exposure to a red <span class="hlt">tide</span> along the Atlantic coast. These actions highlight the importance of rapid investigation of health concerns with potential environmental causes to enable timely notification of the public and prevent further illness.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.nws.noaa.gov/safety.php','SCIGOVWS'); return false;" href="http://www.nws.noaa.gov/safety.php"><span><span class="hlt">Weather</span> Safety - NOAA's National <span class="hlt">Weather</span> Service</span></a></p> <p><a target="_blank" href="http://www.science.gov/aboutsearch.html">Science.gov Websites</a></p> <p></p> <p></p> <p>Statistical Models... MOS Prod GFS-LAMP Prod Climate Past <span class="hlt">Weather</span> Predictions <span class="hlt">Weather</span> <em>Safety</em> <span class="hlt">Weather</span> Radio National <span class="hlt">Weather</span> Service on FaceBook NWS on Facebook NWS Director Home > <em>Safety</em> <span class="hlt">Weather</span> <em>Safety</em> This page <span class="hlt">weather</span> <em>safety</em>. StormReady NOAA <span class="hlt">Weather</span> Radio Emergency Managers Information Network U.S. Hazard Assmt</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017CSR...142...32Z','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017CSR...142...32Z"><span><span class="hlt">Tide</span>-surge interaction along the east coast of the Leizhou Peninsula, South China Sea</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Zhang, Heng; Cheng, Weicong; Qiu, Xixi; Feng, Xiangbo; Gong, Wenping</p> <p>2017-06-01</p> <p>A triply-nested two-dimensional (2D) ocean circulation model along with observed sea level records are used to study <span class="hlt">tide</span>-surge interaction along the east coast of the Leizhou Peninsula (LP) which is characterized by extensive mudflats, large tidal ranges and a complex coastline. The dependency of surge maxima on the water level and the phase of <span class="hlt">tide</span> are respectively investigated using two statistical approaches. Results show that <span class="hlt">tide</span>-surge interaction along the east coast of the LP is significant, where surges peak 3-6 h before or after the nearest high water. The triply-nested 2D ocean circulation model is used to quantify <span class="hlt">tide</span>-surge interaction in this region and to investigate its physical cause. The largest amplitudes of <span class="hlt">tide</span>-surge interaction are found in the shallow water region of the Leizhou Bay, with values up to 1 m during typhoon events. Numerical experiments reveal that nonlinear bottom friction is the main contributor to <span class="hlt">tide</span>-surge interaction, while the contribution of the nonlinear advective effect can be neglected. The shallow water effect enhances the role of nonlinear bottom friction in determining <span class="hlt">tide</span>-surge modulation, leaving the surge peaks usually occur on the rising or falling <span class="hlt">tide</span>. It is also found that the relative contribution of local wind and remote wind is different depending on the storm track and storm intensity, which would finally affect the temporal and spatial distribution of <span class="hlt">tide</span>-surge interaction during typhoon events. These findings confirm the importance of coupling storm surges and <span class="hlt">tides</span> for the prediction of storm surge events in regions which are characterized by shallow water depths and large tidal ranges.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/16206844','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/16206844"><span>Spatial <span class="hlt">variability</span> of characteristics and origins of urban wet <span class="hlt">weather</span> pollution in combined sewers.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Kafi-Benyahia, M; Gromaire, M G; Chebbo, G</p> <p>2005-01-01</p> <p>An experimental on-site observatory of urban pollutant loads in combined sewers was created in the centre of Paris to quantify and characterise the dry and wet <span class="hlt">weather</span> flow in relation to spatial scale. Eight rainfall events were studied from April 2003 to May 2004. Samples were analysed for suspended solids, organic matter, nitrogen and heavy metals. Results confirm the extent of wet <span class="hlt">weather</span> pollution. They have shown the relative homogeneity of SS and organic matter characteristics from one urban catchment area to another. Two groups of heavy metals were identified. The first one concerns Cu, which has a higher concentration in wet <span class="hlt">weather</span> flow (WWF) than in dry <span class="hlt">weather</span> flow (DWF), and runoff. The second includes Cd, Pb and Zn, where higher concentrations were measured in urban runoff than in WWF and DWF. A first evaluation of contribution of wastewater, urban runoff and sewer deposit erosion sources to wet <span class="hlt">weather</span> pollution was established and has highlighted the contribution of wastewater and sewer deposits to this pollution. However, it has shown that sewer deposit erosion remains an important source of wet <span class="hlt">weather</span> pollution at different spatial scales.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.bioone.org/perlserv/?request=get-abstract&doi=10.1672%2F0277-5212%282001%29021%5B0451%3ASHUPON%5D2.0.CO%3B2','USGSPUBS'); return false;" href="http://www.bioone.org/perlserv/?request=get-abstract&doi=10.1672%2F0277-5212%282001%29021%5B0451%3ASHUPON%5D2.0.CO%3B2"><span>Seasonal habitat-use patterns of nekton in a <span class="hlt">tide</span>-restricted and unrestricted New England salt marsh</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Raposa, K.B.; Roman, C.T.</p> <p>2001-01-01</p> <p>Many New England salt marshes remain <span class="hlt">tide</span>-restricted or are undergoing tidal restoration. Hydrologic manipulation of salt marshes affects marsh biogeochemistry and vegetation patterns, but responses by fishes and decapod crustaceans (nekton) remain unclear, This study examines nekton habitat-use patterns in the <span class="hlt">tide</span>-restricted Hatches Harbor salt marsh (Provincetown, Massachusetts) relative to a downstream, unrestricted marsh. Nekton assemblages were sampled in tidal creek, marsh pool, and salt marsh surface habitats. Pools and creeks were sampled every two weeks for one year to account for seasonal <span class="hlt">variability</span>, and the marsh surface was sampled at two-week intervals in summer and fall. Density, richness, and community composition of nekton in creek and marsh surface habitats were similar between the unrestricted and restricted marsh, but use of pools differed drastically on the two sides of the <span class="hlt">tide</span>-restricting dike. In 95% of the cases tested, restricted marsh habitats provided equal or greater habitat value for nekton than the same habitat in the unrestricted marsh (based on density), suggesting that the restricted marsh did not provide a degraded habitat for most species. For some species, the restricted marsh provided nursery, breeding, and overwintering habitat during different seasons, and tidal restoration of this salt marsh must be approached with care to prevent losses of these valuable marsh functions.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016ECSS..175...79L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016ECSS..175...79L"><span>Fish community responses to green <span class="hlt">tides</span> in shallow estuarine and coastal areas</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Le Luherne, E.; Réveillac, E.; Ponsero, A.; Sturbois, A.; Ballu, S.; Perdriau, M.; Le Pape, O.</p> <p>2016-06-01</p> <p>All over the world, numerous bays and estuarine systems that are known to shelter essential fish habitats are experiencing proliferations of green macroalgae known as green <span class="hlt">tides</span>. Although the processes that enhance green <span class="hlt">tides</span> in response to nutrient enrichment are well known, their consequences for ecological communities -especially for ichthyofauna- remain poorly studied. To estimate these consequences, this analysis focused on the two types of shallow systems that are experiencing green <span class="hlt">tides</span>: sandy beaches and estuarine mudflats. In these two systems, macroalgae proliferation and fish community were surveyed along seasonal cycles at control and impacted sites that shared similar physico-chemical parameters and sediment structure. To analyse the consequences of green <span class="hlt">tides</span> on the fish community, a Before-After Control-Impact approach was used. This approach reveals no difference between fish communities at the control and impacted sites before the macroalgal bloom. Then, it underlines an influence of green <span class="hlt">tides</span> on the fish community, and this influence varies according to the composition, density and duration of the macroalgal bloom. Indeed, when intertidal systems experienced short proliferation and/or weak density, green <span class="hlt">tides</span> did not seem to impact the fish community. However, when green macroalgae proliferated in large quantities and/or when the proliferation lasted for long periods, the fish community was significantly affected. These modifications in the fish community led to a significant decrease in fish species diversity and density until fish disappeared from impacted sites at high proliferations. Furthermore, the response of fish species to green <span class="hlt">tides</span> differed according to their functional guilds. Negative consequences for benthic and marine juvenile fish species were beginning at low proliferations, whereas for pelagic fish species they occurred only at high proliferations. Thus, green <span class="hlt">tides</span> significantly affect fish habitat suitability because</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/18443565','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/18443565"><span>A synoptic approach to <span class="hlt">weather</span> conditions discloses a relationship with ambulatory blood pressure in hypertensives.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Morabito, Marco; Crisci, Alfonso; Orlandini, Simone; Maracchi, Giampiero; Gensini, Gian F; Modesti, Pietro A</p> <p>2008-07-01</p> <p>Higher blood pressure (BP) values in cold than in hot months has been documented in hypertensives. These changes may potentially contribute to the observed excess winter cardiovascular mortality. However, the association with <span class="hlt">weather</span> has always been investigated by considering the relationship with a single <span class="hlt">variable</span> rather than considering the combination of ground <span class="hlt">weather</span> <span class="hlt">variables</span> characterizing a specific <span class="hlt">weather</span> pattern (air mass (AM)). We retrospectively investigate in Florence (Italy) the relationship between BP and specific AMs in hypertensive subjects (n = 540) referred to our Hypertension Unit for 24-h ambulatory BP monitoring during the period of the year characterized by the highest <span class="hlt">weather</span> <span class="hlt">variability</span> (winter). Five different winter daily AMs were classified according to the combination of ground <span class="hlt">weather</span> data (air temperature, cloud cover, relative humidity, atmospheric pressure, wind speed, and direction). Multiple <span class="hlt">variable</span> analysis selected the AM as a significant predictor of mean 24-h BP (P < 0.01 for diastolic BP (DBP) and P < 0.05 for systolic BP (SBP)), daytime DBP (P < 0.001) and nighttime BP (P < 0.01 for both SBP and DBP), with higher BP values observed in cyclonic (unstable, cloudy, and mild <span class="hlt">weather</span>) than in anticyclonic (settled, cloudless, and cold <span class="hlt">weather</span>) days. When the association with 2-day sequences of AMs was considered, an increase in ambulatory BP followed a sudden day-to-day change of <span class="hlt">weather</span> pattern going from anticyclonic to cyclonic days. The <span class="hlt">weather</span> considered as a combination of different <span class="hlt">weather</span> <span class="hlt">variables</span> may affect BP. The forecast of a sudden change of AM could provide important information helpful for hypertensives during winter.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li class="active"><span>17</span></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_17 --> <div id="page_18" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li class="active"><span>18</span></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="341"> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19820026847&hterms=infrasound&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D20%26Ntt%3Dinfrasound','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19820026847&hterms=infrasound&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D20%26Ntt%3Dinfrasound"><span>Stratospheric <span class="hlt">variability</span> in summer</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Rind, D.; Donn, W. L.; Robinson, W.</p> <p>1981-01-01</p> <p>Rocketsonde observations and infrasound results are used to investigate the <span class="hlt">variability</span> of the summer stratopause region during one month in summer. Fluctuations of 2-3 days and about 16-day periods are evident, and they appear to be propagating vertically. In this month the 2-3 day oscillations have an amplitude envelope equal in period to the longer period oscillations, implying a connection between the two phenomena. Observations of the diurnal <span class="hlt">tide</span> and shorter period <span class="hlt">variability</span> during the month are also presented.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017SPIE10422E..1EH','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017SPIE10422E..1EH"><span>The influence of <span class="hlt">tide</span> on sea surface temperature in the marginal sea of northwest Pacific Ocean</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Huang, Shih-Jen; Tsai, Yun-Chan; Ho, Chung-Ru; Lo, Yao-Tsai; Kuo, Nan-Jung</p> <p>2017-10-01</p> <p><span class="hlt">Tide</span> gauge data provided by the University of Hawaii Sea Level Center and daily sea surface temperature (SST) data from the Moderate Resolution Imaging Spectroradiometer (MODIS) product are used in this study to analyze the influence of <span class="hlt">tide</span> on the SST in the seas of Northwestern Pacific. In the marginal region, the climatology SST is lower in the northwestern area than that in the southeastern area. In the coastal region, the SST at spring <span class="hlt">tide</span> is higher than that at neap <span class="hlt">tide</span> in winter, but it is lower in other seasons. In the adjacent waters of East China Sea and Yellow Sea, the SST at spring <span class="hlt">tide</span> is higher than that at neap <span class="hlt">tide</span> in winter and summer but it is lower in spring and autumn. In the open ocean region, the SST at spring <span class="hlt">tide</span> is higher than that at neap <span class="hlt">tide</span> in winter, but it is lower in other seasons. In conclusion, not only the river discharge and topography, but also <span class="hlt">tides</span> could influence the SST variations, especially in the open ocean region.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017EGUGA..19.4784J','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017EGUGA..19.4784J"><span>Modelling the influence of <span class="hlt">tides</span> on ice-shelf melt rates in the Amundsen Sea, Antarctica.</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Jourdain, Nicolas C.; Molines, Jean-Marc; Le Sommer, Julien; Mathiot, Pierre; Chanut, Jérome; Madec, Gurvan</p> <p>2017-04-01</p> <p>Variations in melt beneath ice- shelves may trigger ice-sheet instabilities, in particular in West Antarctica. Therefore, improving the understanding and modelling of ice-shelf basal melt rates has been a major focus over the last decades. In this presentation, we provide further insight into the role of <span class="hlt">tides</span> on basal melt rates, and we assess several methods to account for <span class="hlt">tides</span> in models that do not include an explicit representation of <span class="hlt">tides</span>. First, we use an explicit representation of <span class="hlt">tides</span> in a regional configuration of the NEMO-3.6 model deployed over the Amundsen Sea. We show that most of the tidal influence on ice-shelf melt is explained by four tidal constituents. <span class="hlt">Tides</span> enhance melt by more than 30% in some cavities like Abbot, Cosgrove and Dotson, but by less than 10% in others like Thwaites and Pine Island. Over the entire Amundsen Sea sector, <span class="hlt">tides</span> enhance melt by 92 Gt/yr, which is mostly induced by tidal velocities along ice drafts (+148 Gt/yr), partly compensated by <span class="hlt">tide</span>-induced change in thermal forcing (-31 Gt/yr) and co-variations between tidal velocities and thermal forcing (-26 Gt/yr). In the second part of this presentation, we show that using uniform tidal velocities to account for <span class="hlt">tides</span> effects in ocean models with no explicit <span class="hlt">tides</span> produces large biases in melt rates. By contrast, prescribing non-uniform tidal velocities allows an accurate representation of the dynamical effects of <span class="hlt">tides</span> on melt rates.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012AGUFMOS11C1651A','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012AGUFMOS11C1651A"><span>Errors in Tsunami Source Estimation from <span class="hlt">Tide</span> Gauges</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Arcas, D.</p> <p>2012-12-01</p> <p>Linearity of tsunami waves in deep water can be assessed as a comparison of flow speed, u to wave propagation speed √gh. In real tsunami scenarios this evaluation becomes impractical due to the absence of observational data of tsunami flow velocities in shallow water. Consequently the extent of validity of the linear regime in the ocean is unclear. Linearity is the fundamental assumption behind tsunami source inversion processes based on linear combinations of unit propagation runs from a deep water propagation database (Gica et al., 2008). The primary tsunami elevation data for such inversion is usually provided by National Oceanic and Atmospheric (NOAA) deep-water tsunami detection systems known as DART. The use of <span class="hlt">tide</span> gauge data for such inversions is more controversial due to the uncertainty of wave linearity at the depth of the <span class="hlt">tide</span> gauge site. This study demonstrates the inaccuracies incurred in source estimation using <span class="hlt">tide</span> gauge data in conjunction with a linear combination procedure for tsunami source estimation.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ars.usda.gov/research/publications/publication/?seqNo115=338893','TEKTRAN'); return false;" href="http://www.ars.usda.gov/research/publications/publication/?seqNo115=338893"><span>Climate, <span class="hlt">weather</span>, and hops</span></a></p> <p><a target="_blank" href="https://www.ars.usda.gov/research/publications/find-a-publication/">USDA-ARS?s Scientific Manuscript database</a></p> <p></p> <p></p> <p>As climate and <span class="hlt">weather</span> become more <span class="hlt">variable</span>, hop growers face increased uncertainty in making decisions about their crop. Given the unprecedented nature of these changes, growers may no longer have enough information and intuitive understanding to adequately assess the situation and evaluate their m...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/19879288','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/19879288"><span>Characterization of Florida red <span class="hlt">tide</span> aerosol and the temporal profile of aerosol concentration.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Cheng, Yung Sung; Zhou, Yue; Pierce, Richard H; Henry, Mike; Baden, Daniel G</p> <p>2010-05-01</p> <p>Red <span class="hlt">tide</span> aerosols containing aerosolized brevetoxins are produced during the red <span class="hlt">tide</span> bloom and transported by wind to coastal areas of Florida. This study reports the characterization of Florida red <span class="hlt">tide</span> aerosols in human volunteer studies, in which an asthma cohort spent 1h on Siesta Beach (Sarasota, Florida) during aerosolized red <span class="hlt">tide</span> events and non-exposure periods. Aerosol concentrations, brevetoxin levels, and particle size distribution were measured. Hourly filter samples were taken and analyzed for brevetoxin and NaCl concentrations. In addition, the aerosol mass concentration was monitored in real time. The results indicated that during a non-exposure period in October 2004, no brevetoxin was detected in the water, resulting in non-detectable levels of brevetoxin in the aerosol. In March 2005, the time-averaged concentrations of brevetoxins in water samples were moderate, in the range of 5-10 microg/L, and the corresponding brevetoxin level of Florida red <span class="hlt">tide</span> aerosol ranged between 21 and 39 ng/m(3). The temporal profiles of red <span class="hlt">tide</span> aerosol concentration in terms of mass, NaCl, and brevetoxin were in good agreement, indicating that NaCl and brevetoxins are components of the red <span class="hlt">tide</span> aerosol. By continuously monitoring the marine aerosol and wind direction at Siesta Beach, we observed that the marine aerosol concentration varied as the wind direction changed. The temporal profile of the Florida red <span class="hlt">tide</span> aerosol during a sampling period could be explained generally with the variation of wind direction. Copyright 2009 Elsevier Ltd. All rights reserved.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20130001890','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20130001890"><span>Successfully Transitioning Science Research to Space <span class="hlt">Weather</span> Applications</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Spann, James</p> <p>2012-01-01</p> <p>The awareness of potentially significant impacts of space <span class="hlt">weather</span> on spaceand ground ]based technological systems has generated a strong desire in many sectors of government and industry to effectively transform knowledge and understanding of the <span class="hlt">variable</span> space environment into useful tools and applications for use by those entities responsible for systems that may be vulnerable to space <span class="hlt">weather</span> impacts. Essentially, effectively transitioning science knowledge to useful applications relevant to space <span class="hlt">weather</span> has become important. This talk will present proven methodologies that have been demonstrated to be effective, and how in the current environment those can be applied to space <span class="hlt">weather</span> transition efforts.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015IJBm...59.1269M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015IJBm...59.1269M"><span><span class="hlt">Weather</span> elements, chemical air pollutants and airborne pollen influencing asthma emergency room visits in Szeged, Hungary: performance of two objective <span class="hlt">weather</span> classifications</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Makra, László; Puskás, János; Matyasovszky, István; Csépe, Zoltán; Lelovics, Enikő; Bálint, Beatrix; Tusnády, Gábor</p> <p>2015-09-01</p> <p><span class="hlt">Weather</span> classification approaches may be useful tools in modelling the occurrence of respiratory diseases. The aim of the study is to compare the performance of an objectively defined <span class="hlt">weather</span> classification and the Spatial Synoptic Classification (SSC) in classifying emergency department (ED) visits for acute asthma depending from <span class="hlt">weather</span>, air pollutants, and airborne pollen <span class="hlt">variables</span> for Szeged, Hungary, for the 9-year period 1999-2007. The research is performed for three different pollen-related periods of the year and the annual data set. According to age and gender, nine patient categories, eight meteorological <span class="hlt">variables</span>, seven chemical air pollutants, and two pollen categories were used. In general, partly dry and cold air and partly warm and humid air aggravate substantially the symptoms of asthmatics. Our major findings are consistent with this establishment. Namely, for the objectively defined <span class="hlt">weather</span> types favourable conditions for asthma ER visits occur when an anticyclonic ridge <span class="hlt">weather</span> situation happens with near extreme temperature and humidity parameters. Accordingly, the SSC <span class="hlt">weather</span> types facilitate aggravating asthmatic conditions if warm or cool <span class="hlt">weather</span> occur with high humidity in both cases. Favourable conditions for asthma attacks are confirmed in the extreme seasons when atmospheric stability contributes to enrichment of air pollutants. The total efficiency of the two classification approaches is similar in spite of the fact that the methodology for derivation of the individual types within the two classification approaches is completely different.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/25504051','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/25504051"><span><span class="hlt">Weather</span> elements, chemical air pollutants and airborne pollen influencing asthma emergency room visits in Szeged, Hungary: performance of two objective <span class="hlt">weather</span> classifications.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Makra, László; Puskás, János; Matyasovszky, István; Csépe, Zoltán; Lelovics, Enikő; Bálint, Beatrix; Tusnády, Gábor</p> <p>2015-09-01</p> <p><span class="hlt">Weather</span> classification approaches may be useful tools in modelling the occurrence of respiratory diseases. The aim of the study is to compare the performance of an objectively defined <span class="hlt">weather</span> classification and the Spatial Synoptic Classification (SSC) in classifying emergency department (ED) visits for acute asthma depending from <span class="hlt">weather</span>, air pollutants, and airborne pollen <span class="hlt">variables</span> for Szeged, Hungary, for the 9-year period 1999-2007. The research is performed for three different pollen-related periods of the year and the annual data set. According to age and gender, nine patient categories, eight meteorological <span class="hlt">variables</span>, seven chemical air pollutants, and two pollen categories were used. In general, partly dry and cold air and partly warm and humid air aggravate substantially the symptoms of asthmatics. Our major findings are consistent with this establishment. Namely, for the objectively defined <span class="hlt">weather</span> types favourable conditions for asthma ER visits occur when an anticyclonic ridge <span class="hlt">weather</span> situation happens with near extreme temperature and humidity parameters. Accordingly, the SSC <span class="hlt">weather</span> types facilitate aggravating asthmatic conditions if warm or cool <span class="hlt">weather</span> occur with high humidity in both cases. Favourable conditions for asthma attacks are confirmed in the extreme seasons when atmospheric stability contributes to enrichment of air pollutants. The total efficiency of the two classification approaches is similar in spite of the fact that the methodology for derivation of the individual types within the two classification approaches is completely different.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2011AGUFMNG51A1652L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2011AGUFMNG51A1652L"><span>Do GCM's Predict the Climate.... Or the Low Frequency <span class="hlt">Weather</span>?</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Lovejoy, S.; Varon, D.; Schertzer, D. J.</p> <p>2011-12-01</p> <p>Over twenty-five years ago, a three-regime scaling model was proposed describing the statistical <span class="hlt">variability</span> of the atmosphere over time scales ranging from <span class="hlt">weather</span> scales out to ≈ 100 kyrs. Using modern in situ data reanalyses, monthly surface series (at 5ox5o), 8 "multiproxy" (yearly) series of the Northern hemisphere from 1500- 1980, and GRIP and Vostok paleotemperatures at 5.2 and ≈ 100 year resolutions (over the past 91-420 kyrs), we refine the model and show how it can be understood with the help of new developments in nonlinear dynamics, especially multifractals and cascades. In a scaling range, mean fluctuations in state <span class="hlt">variables</span> such as temperature ΔT ≈ ΔtH the where Δt is the duration. At small (<span class="hlt">weather</span>) scales the fluctuation exponents are generally H>0; they grow with scale. At longer scales Δt >τw (≈ 10 days) they change sign, the fluctuations decrease with scale; this is the low <span class="hlt">variability</span>, "low frequency <span class="hlt">weather</span>" regime the spectrum is a relatively flat "plateau", it's <span class="hlt">variability</span> is that of the usual idea of "long term <span class="hlt">weather</span> statistics". Finally for longer times, Δt>τc ≈ 10 - 100 years, again H>0, the <span class="hlt">variability</span> again increases with scale. This is the true climate regime. These scaling regimes allow us to objectively define the <span class="hlt">weather</span> as fluctuations over periods <τw, "climate states", as fluctuations at scale τc and "climate change" as the fluctuations at longer periods >τc). We show that the intermediate regime is the result of the <span class="hlt">weather</span> regime undergoing a "dimensional transition": at temporal scales longer than the typical lifetime of planetary structures (τw), the spatial degrees of freedom are rapidly quenched, only the temporal degrees of freedom are important. This low frequency <span class="hlt">weather</span> regime has statistical properties well reproduced not only by <span class="hlt">weather</span> cascade models, but also by control runs (i.e. without climate forcing) of GCM's (including IPSL and ECHAM GCM's). In order for GCM's to go beyond simply</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19950049128&hterms=oceans+tide&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D20%26Ntt%3Doceans%2Btide','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19950049128&hterms=oceans+tide&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D20%26Ntt%3Doceans%2Btide"><span>Geographical representation of radial orbit perturbations due to ocean <span class="hlt">tides</span>: Implications for satellite altimetry</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Bettadpur, Srinivas V.; Eanes, Richard J.</p> <p>1994-01-01</p> <p>In analogy to the geographical representation of the zeroth-order radial orbit perturbations due to the static geopotential, similar relationships have been derived for radial orbit perturbations due to the ocean <span class="hlt">tides</span>. At each location these perturbations are seen to be coherent with the <span class="hlt">tide</span> height variations. The study of this singularity is of obvious importance to the estimation of ocean <span class="hlt">tides</span> from satellite altimeter data. We derive analytical expressions for the sensitivity of altimeter derived ocean <span class="hlt">tide</span> models to the ocean <span class="hlt">tide</span> force model induced errors in the orbits of the altimeter satellite. In particular, we focus on characterizing and quantifying the nonresonant tidal orbit perturbations, which cannot be adjusted into the empirical accelerations or radial perturbation adjustments commonly used during orbit determination and in altimeter data processing. As an illustration of the utility of this technique, we study the differences between a TOPEX/POSEIDON-derived ocean <span class="hlt">tide</span> model and the Cartwright and Ray 1991 Geosat model. This analysis shows that nearly 60% of the variance of this difference for M(sub 2) can be explained by the Geosat radial orbit eror due to the omission of coefficients from the GEM-T2 background ocean <span class="hlt">tide</span> model. For O(sub 1), K(sub 1), S(sub 2), and K(sub 2) the orbital effects account for approximately 10 to 40% of the variances of these differences. The utility of this technique to assessment of the ocean <span class="hlt">tide</span> induced errors in the TOPEX/POSEIDON-derived <span class="hlt">tide</span> models is also discussed.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/biblio/7302582-aem-tem-study-weathering-diagenesis-abert-lake-oregon-weathering-reactions-volcanics','SCIGOV-STC'); return false;" href="https://www.osti.gov/biblio/7302582-aem-tem-study-weathering-diagenesis-abert-lake-oregon-weathering-reactions-volcanics"><span>An AEM-TEM study of <span class="hlt">weathering</span> and diagenesis, Abert Lake, Oregon. (1) <span class="hlt">Weathering</span> reactions in the volcanics</span></a></p> <p><a target="_blank" href="http://www.osti.gov/search">DOE Office of Scientific and Technical Information (OSTI.GOV)</a></p> <p>Banfield, J.F.; Veblen, D.R.; Jones, B.F.</p> <p>1991-10-01</p> <p>Abert Lake in south-central Oregon provides a site suitable for the study of sequential <span class="hlt">weathering</span> and diagenetic events. In this first of two papers, transmission electron microscopy was used to characterize the igneous mineralogy, subsolidus alteration assemblage, and the structural and chemical aspects of silicate <span class="hlt">weathering</span> reactions that occur in the volcanic rocks that outcrop around the lake. Olivine and pyroxene replacement occurred topotactically, whereas feldspar and glass alteration produced randomly oriented smectite in channels and cavities. The tetrahedral, octahedral, and interlayer compositions of the <span class="hlt">weathering</span> products, largely dioctahedral smectites, varied with primary mineral composition, rock type, and as themore » result of addition of elements released from adjacent reaction sites. The <span class="hlt">variability</span> within and between the smectite assemblages highlights the microenvironmental diversity, fluctuating redox conditions, and <span class="hlt">variable</span> solution chemistry associated with mineral <span class="hlt">weathering</span> reactions in the surficial environment. Late-stage exhalative and aqueous alteration of the volcanics redistributed many components and formed a variety of alkali and alkali-earth carbonate, chloride, sulfate, and fluoride minerals in vugs and cracks. Overall, substantial Mg, Si, Na, Ca, and K are released by <span class="hlt">weathering</span> reactions that include the almost complete destruction of the Mg-smectite that initially replaced olivine. The leaching of these elements from the volcanics provides an important source of these constituents in the lake water. The nature of subsequent diagenetic reactions resulting from the interaction between the materials transported to the lake and the solution will be described in part.« less</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016JGRC..121.7599S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016JGRC..121.7599S"><span>Tidal distortion caused by the resonance of sexta-diurnal <span class="hlt">tides</span> in a micromesotidal embayment</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Song, Dehai; Yan, Yuhan; Wu, Wen; Diao, Xiliang; Ding, Yang; Bao, Xianwen</p> <p>2016-10-01</p> <p>Double high water and double-peak flood current were observed in Daya Bay (DYB), China, which is a shallow, mixed, mainly semidiurnal-<span class="hlt">tide</span> dominated bay with a micro to mesotidal range. Harmonic analysis reveals that the quarter and especially the sexta-diurnal constituents are getting much stronger as <span class="hlt">tides</span> propagating into the bay. The astronomical <span class="hlt">tides</span>-induced tidal asymmetry is yet dominant at the bay entrance but overtaken by the sexta-diurnal <span class="hlt">tides</span> at the end of the bay. Both the M4 and M6 <span class="hlt">tide</span> meet the requirement proposed in previous studies but still unable to produce a double high water alone. Therefore, the conditions to produce a double high water between a fundamental <span class="hlt">tide</span> and its higher harmonics need to be revisited. Analytical solutions were obtained in this paper, which fit the numerical solutions very well. Modeling result indicates M6 alone with M2 can produce the double high water in DYB but limited in some regions, while the combination of M2, M4, and M6 <span class="hlt">tides</span> would enhance the capability. The amplification of sexta-diurnal <span class="hlt">tides</span> in DYB is dominated by resonance and followed by shoaling effect. Bottom friction damped M6 a lot and largely confined its amplification. However, the quadratic friction and other nonlinear processes are just responsible for about 10% of the total M6 increase.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2010JGRC..115.6020R','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2010JGRC..115.6020R"><span>Nonlinear terms in storm surge predictions: Effect of <span class="hlt">tide</span> and shelf geometry with case study from Hurricane Rita</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Rego, JoãO. L.; Li, Chunyan</p> <p>2010-06-01</p> <p>This study applied the finite volume coastal ocean model (FVCOM) to the storm surge induced by Hurricane Rita along the Louisiana-Texas coast. The model was calibrated for <span class="hlt">tides</span> and validated with observed water levels. Peak water levels were shown to be lower than expected for a landfall at high <span class="hlt">tide</span>. For low- and high-<span class="hlt">tide</span> landfalls, nonlinear effects due to <span class="hlt">tide</span>-surge coupling were constructive and destructive to total storm <span class="hlt">tide</span>, respectively, and their magnitude reached up to 70% of the tidal amplitude in the Rita application. <span class="hlt">Tide</span>-surge interaction was further examined using a standard hurricane under idealized scenarios to evaluate the effects of various shelf geometries, <span class="hlt">tides</span>, and landfall timings (relative to <span class="hlt">tide</span>). Nonlinearity was important between landfall position and locations within 2.5 × radius of maximum winds. On an idealized wide continental shelf, nonlinear effects reached up to 80% of the tidal amplitude with an S2 <span class="hlt">tide</span> and up to 47% with a K1 <span class="hlt">tide</span>. Increasing average depths by 4 m reduced nonlinear effects to 41% of the tidal amplitude; increasing the slope by a factor of 3 produced nonlinearities of just 26% of <span class="hlt">tide</span> (both with a K1 <span class="hlt">tide</span>). The nonlinear effect was greatest for landfalls at low <span class="hlt">tide</span>, followed by landfalls at high <span class="hlt">tide</span> and then by landfalls at midebb or midflood.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/biblio/5036069-effects-dynamic-long-period-ocean-tides-changes-earth-rotation-rate','SCIGOV-STC'); return false;" href="https://www.osti.gov/biblio/5036069-effects-dynamic-long-period-ocean-tides-changes-earth-rotation-rate"><span>Effects of dynamic long-period ocean <span class="hlt">tides</span> on changes in Earth's rotation rate</span></a></p> <p><a target="_blank" href="http://www.osti.gov/search">DOE Office of Scientific and Technical Information (OSTI.GOV)</a></p> <p>Nam, Y.S.; Dickman, S.R.</p> <p>1990-05-10</p> <p>As a generalization of the zonal response coefficient first introduced by Agnew and Farrell (1978), the authors define the zonal response function k of the solid earth-ocean system as the ratio, in the frequency domain, of the tidal change in Earth's rotation rate to the <span class="hlt">tide</span>-generating potential. Amplitudes and phases of k for the monthly, fortnightly, and 9-day lunar <span class="hlt">tides</span> are estimated from 2 1/2 years of very long baseline interferometry UTI observations (both 5-day and daily time series), corrected for atmospheric angular momentum effects using NMC wind and pressure series. Using the dynamic ocean <span class="hlt">tide</span> model of Dickman (1988a,more » 1989a), the authors predict amplitudes and phases of k for an elastic earth-ocean system. The predictions confirm earlier results which found that dynamic effects of the longer-period ocean <span class="hlt">tides</span> reduce the amplitude of k by about 1%. However, agreement with the observed k is best achieved for all three <span class="hlt">tides</span> if the predicted <span class="hlt">tide</span> amplitudes are combined with the much larger satellite-observed ocean <span class="hlt">tide</span> phases; in these cases the dynamic tidal effects reduce k by up to 8%. Finally, comparison between the observed and predicted amplitudes of k implies that anelastic effects on Earth's rotation at periods less than fortnightly cannot exceed 2%.« less</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018AMT....11.2027H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018AMT....11.2027H"><span>Using barometric time series of the IMS infrasound network for a global analysis of thermally induced atmospheric <span class="hlt">tides</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Hupe, Patrick; Ceranna, Lars; Pilger, Christoph</p> <p>2018-04-01</p> <p>The International Monitoring System (IMS) has been established to monitor compliance with the Comprehensive Nuclear-Test-Ban Treaty and comprises four technologies, one of which is infrasound. When fully established, the IMS infrasound network consists of 60 sites uniformly distributed around the globe. Besides its primary purpose of determining explosions in the atmosphere, the recorded data reveal information on other anthropogenic and natural infrasound sources. Furthermore, the almost continuous multi-year recordings of differential and absolute air pressure allow for analysing the atmospheric conditions. In this paper, spectral analysis tools are applied to derive atmospheric dynamics from barometric time series. Based on the solar atmospheric <span class="hlt">tides</span>, a methodology for performing geographic and temporal <span class="hlt">variability</span> analyses is presented, which is supposed to serve for upcoming studies related to atmospheric dynamics. The surplus value of using the IMS infrasound network data for such purposes is demonstrated by comparing the findings on the thermal <span class="hlt">tides</span> with previous studies and the Modern-Era Retrospective analysis for Research and Applications Version 2 (MERRA-2), which represents the solar <span class="hlt">tides</span> well in its surface pressure fields. Absolute air pressure recordings reveal geographical characteristics of atmospheric <span class="hlt">tides</span> related to the solar day and even to the lunar day. We therefore claim the chosen methodology of using the IMS infrasound network to be applicable for global and temporal studies on specific atmospheric dynamics. Given the accuracy and high temporal resolution of the barometric data from the IMS infrasound network, interactions with gravity waves and planetary waves can be examined in future for refining the knowledge of atmospheric dynamics, e.g. the origin of tidal harmonics up to 9 cycles per day as found in the barometric data sets. Data assimilation in empirical models of solar <span class="hlt">tides</span> would be a valuable application of the IMS infrasound</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018ISPAr42.3..573H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018ISPAr42.3..573H"><span>Research on High Accuracy Detection of Red <span class="hlt">Tide</span> Hyperspecrral Based on Deep Learning Cnn</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Hu, Y.; Ma, Y.; An, J.</p> <p>2018-04-01</p> <p>Increasing frequency in red <span class="hlt">tide</span> outbreaks has been reported around the world. It is of great concern due to not only their adverse effects on human health and marine organisms, but also their impacts on the economy of the affected areas. this paper put forward a high accuracy detection method based on a fully-connected deep CNN detection model with 8-layers to monitor red <span class="hlt">tide</span> in hyperspectral remote sensing images, then make a discussion of the glint suppression method for improving the accuracy of red <span class="hlt">tide</span> detection. The results show that the proposed CNN hyperspectral detection model can detect red <span class="hlt">tide</span> accurately and effectively. The red <span class="hlt">tide</span> detection accuracy of the proposed CNN model based on original image and filter-image is 95.58 % and 97.45 %, respectively, and compared with the SVM method, the CNN detection accuracy is increased by 7.52 % and 2.25 %. Compared with SVM method base on original image, the red <span class="hlt">tide</span> CNN detection accuracy based on filter-image increased by 8.62 % and 6.37 %. It also indicates that the image glint affects the accuracy of red <span class="hlt">tide</span> detection seriously.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016APS..DFDG13009S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016APS..DFDG13009S"><span>Capturing remote mixing due to internal <span class="hlt">tides</span> using multi-scale modeling tool: SOMAR-LES</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Santilli, Edward; Chalamalla, Vamsi; Scotti, Alberto; Sarkar, Sutanu</p> <p>2016-11-01</p> <p>Internal <span class="hlt">tides</span> that are generated during the interaction of an oscillating barotropic <span class="hlt">tide</span> with the bottom bathymetry dissipate only a fraction of their energy near the generation region. The rest is radiated away in the form of low- high-mode internal <span class="hlt">tides</span>. These internal <span class="hlt">tides</span> dissipate energy at remote locations when they interact with the upper ocean pycnocline, continental slope, and large scale eddies. Capturing the wide range of length and time scales involved during the life-cycle of internal <span class="hlt">tides</span> is computationally very expensive. A recently developed multi-scale modeling tool called SOMAR-LES combines the adaptive grid refinement features of SOMAR with the turbulence modeling features of a Large Eddy Simulation (LES) to capture multi-scale processes at a reduced computational cost. Numerical simulations of internal <span class="hlt">tide</span> generation at idealized bottom bathymetries are performed to demonstrate this multi-scale modeling technique. Although each of the remote mixing phenomena have been considered independently in previous studies, this work aims to capture remote mixing processes during the life cycle of an internal <span class="hlt">tide</span> in more realistic settings, by allowing multi-level (coarse and fine) grids to co-exist and exchange information during the time stepping process.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017AGUFM.B23A2052T','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017AGUFM.B23A2052T"><span>Atmospheric Transport of Nutrient Matter during a Red <span class="hlt">Tide</span> Event</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Tian, R.; Weng, H.; Lin, Q.</p> <p>2017-12-01</p> <p>Harmful algal blooms (HABs) resulting from an explosive increase in algae population have become a global problem in coastal marine environment. During 3rd -8th, May of 2006, large-scale, mixed prorocentrum dentatum stein and skeletonema costatum bloom developed in those water off the coast of Zhejiang province (Zhoushan city and Liuheng Island) of China. Using Global Nested Air Quality Prediction Modeling System (GNAQPMS), we find an atmospheric transport of considerable nutrient matter (nitrate, ammonium, Fe (Ⅱ)) to East China Sea (ECS) before the red <span class="hlt">tide</span> event. It be inferred that the atmospheric transport of nutrient matter is a significant source of nutrient matter in the water of East China Sea whose hydrological setting is dominated by oligotrophic Taiwan Warm Current in spring. Such atmospheric transport of nutrient matter is likely a cause factor of red <span class="hlt">tide</span> in the coast of East China Sea, especially during dust event. The study provides new information for discovering the occurring mechanism of the red <span class="hlt">tides</span> in ECS and the essential parameters for the red <span class="hlt">tide</span> research.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/29602505','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/29602505"><span>Consortial brown <span class="hlt">tide</span> - picocyanobacteria blooms in Guantánamo Bay, Cuba.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Hall, Nathan S; Litaker, R Wayne; Kenworthy, W Judson; Vandersea, Mark W; Sunda, William G; Reid, James P; Slone, Daniel H; Butler, Susan</p> <p>2018-03-01</p> <p>A brown <span class="hlt">tide</span> bloom of Aureoumbra lagunensis developed in Guantánamo Bay, Cuba during a period of drought in 2013 that followed heavy winds and rainfall from Hurricane Sandy in late October 2012. Based on satellite images and water turbidity measurements, the bloom appeared to initiate in January 2013. The causative species (A. lagunensis) was confirmed by microscopic observation, and pigment and genetic analyses of bloom samples collected on May 28 of that year. During that time, A. lagunensis reached concentrations of 900,000 cells ml -1 (28 ppm by biovolume) in the middle portion of the Bay. Samples could not be collected from the northern (Cuban) half of the Bay because of political considerations. Subsequent sampling of the southern half of the Bay in November 2013, April 2014, and October 2014 showed persistent lower concentrations of A. lagunensis, with dominance shifting to the cyanobacterium Synechococcus (up to 33 ppm in April), an algal group that comprised a minor bloom component on May 28. Thus, unlike the brown <span class="hlt">tide</span> bloom in Laguna Madre, which lasted 8 years, the bloom in Guantánamo Bay was short-lived, much like recent blooms in the Indian River, Florida. Although hypersaline conditions have been linked to brown <span class="hlt">tide</span> development in the lagoons of Texas and Florida, observed euhaline conditions in Guantánamo Bay (salinity 35-36) indicate that strong hypersalinity is not a requirement for A. lagunensis bloom formation. Microzooplankton biomass dominated by ciliates was high during the observed peak of the brown <span class="hlt">tide</span>, and ciliate abundance was high compared to other systems not impacted by brown <span class="hlt">tide</span>. Preferential grazing by zooplankton on non-brown <span class="hlt">tide</span> species, as shown in A. lagunensis blooms in Texas and Florida, may have been a factor in the development of the Cuban brown <span class="hlt">tide</span> bloom. However, subsequent selection of microzooplankton capable of utilizing A. lagunensis as a primary food source may have contributed to the short-lived duration</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li class="active"><span>18</span></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_18 --> <div id="page_19" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li class="active"><span>19</span></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="361"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.dtic.mil/docs/citations/ADA630138','DTIC-ST'); return false;" href="http://www.dtic.mil/docs/citations/ADA630138"><span>The Analysis, Numerical Simulation, and Diagnosis of Extratropical <span class="hlt">Weather</span> Systems</span></a></p> <p><a target="_blank" href="http://www.dtic.mil/">DTIC Science & Technology</a></p> <p></p> <p>1999-09-30</p> <p>The Analysis, Numerical Simulation, and Diagnosis of Extratropical <span class="hlt">Weather</span> Systems Dr. Melvyn A. Shapiro NOAA/Environmental Technology Laboratory...formulation, and numerical prediction of the life cycles of synoptic-scale and mesoscale extratropical <span class="hlt">weather</span> systems, including the influence of planetary...scale inter-annual and intra-seasonal <span class="hlt">variability</span> on their evolution. These <span class="hlt">weather</span> systems include: extratropical oceanic and land-falling cyclones</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://cfpub.epa.gov/si/si_public_record_report.cfm?dirEntryId=241685&keyword=temperature+AND+variability&actType=&TIMSType=+&TIMSSubTypeID=&DEID=&epaNumber=&ntisID=&archiveStatus=Both&ombCat=Any&dateBeginCreated=&dateEndCreated=&dateBeginPublishedPresented=&dateEndPublishedPresented=&dateBeginUpdated=&dateEndUpdated=&dateBeginCompleted=&dateEndCompleted=&personID=&role=Any&journalID=&publisherID=&sortBy=revisionDate&count=50','EPA-EIMS'); return false;" href="https://cfpub.epa.gov/si/si_public_record_report.cfm?dirEntryId=241685&keyword=temperature+AND+variability&actType=&TIMSType=+&TIMSSubTypeID=&DEID=&epaNumber=&ntisID=&archiveStatus=Both&ombCat=Any&dateBeginCreated=&dateEndCreated=&dateBeginPublishedPresented=&dateEndPublishedPresented=&dateBeginUpdated=&dateEndUpdated=&dateBeginCompleted=&dateEndCompleted=&personID=&role=Any&journalID=&publisherID=&sortBy=revisionDate&count=50"><span>Pacific Northwest <span class="hlt">tide</span> channel utilization by fish as an ecosystem service</span></a></p> <p><a target="_blank" href="http://oaspub.epa.gov/eims/query.page">EPA Science Inventory</a></p> <p></p> <p></p> <p>Background/Question/Methods: Saltwater marsh <span class="hlt">tide</span> channels are considered to be important in the ecology of estuarine fish serving both as a refuge and as a provider of enhanced food resources. However, this presumed function of <span class="hlt">tide</span> channels in Pacific Northwest estuaries has ...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=20060054001&hterms=reproduction&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D80%26Ntt%3Dreproduction','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=20060054001&hterms=reproduction&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D80%26Ntt%3Dreproduction"><span>Validating the Airspace Concept Evaluation System for Different <span class="hlt">Weather</span> Days</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Zelinski, Shannon; Meyn, Larry</p> <p>2006-01-01</p> <p>This paper extends the process for validating the Airspace Concept Evaluation System using real-world historical flight operational data. System inputs such as flight plans and airport en-route capacities, are generated and processed to create a realistic reproduction of a single day's operations within the National Airspace System. System outputs such as airport throughput, delays, and en-route sector loads are then compared to real world operational metrics and delay statistics for the reproduced day. The process is repeated for 4 historical days with high and low traffic volume and delay attributed to <span class="hlt">weather</span>. These 4 days are simulated using default en-route capacities and <span class="hlt">variable</span> en-route capacities used to emulate <span class="hlt">weather</span>. The validation results show that default enroute capacity simulations are closer to real-world data for low <span class="hlt">weather</span> days than high <span class="hlt">weather</span> days. The use of reduced <span class="hlt">variable</span> enroute capacities adds a large delay bias to ACES but delay trends between <span class="hlt">weather</span> days are better represented.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013JGRC..118.6303M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013JGRC..118.6303M"><span>Internal <span class="hlt">tide</span> generation by abyssal hills using analytical theory</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Melet, Angélique; Nikurashin, Maxim; Muller, Caroline; Falahat, S.; Nycander, Jonas; Timko, Patrick G.; Arbic, Brian K.; Goff, John A.</p> <p>2013-11-01</p> <p>Internal <span class="hlt">tide</span> driven mixing plays a key role in sustaining the deep ocean stratification and meridional overturning circulation. Internal <span class="hlt">tides</span> can be generated by topographic horizontal scales ranging from hundreds of meters to tens of kilometers. State of the art topographic products barely resolve scales smaller than ˜10 km in the deep ocean. On these scales abyssal hills dominate ocean floor roughness. The impact of abyssal hill roughness on internal-<span class="hlt">tide</span> generation is evaluated in this study. The conversion of M2 barotropic to baroclinic tidal energy is calculated based on linear wave theory both in real and spectral space using the Shuttle Radar Topography Mission SRTM30_PLUS bathymetric product at 1/120° resolution with and without the addition of synthetic abyssal hill roughness. Internal <span class="hlt">tide</span> generation by abyssal hills integrates to 0.1 TW globally or 0.03 TW when the energy flux is empirically corrected for supercritical slope (i.e., ˜10% of the energy flux due to larger topographic scales resolved in standard products in both cases). The abyssal hill driven energy conversion is dominated by mid-ocean ridges, where abyssal hill roughness is large. Focusing on two regions located over the Mid-Atlantic Ridge and the East Pacific Rise, it is shown that regionally linear theory predicts an increase of the energy flux due to abyssal hills of up to 100% or 60% when an empirical correction for supercritical slopes is attempted. Therefore, abyssal hills, unresolved in state of the art topographic products, can have a strong impact on internal <span class="hlt">tide</span> generation, especially over mid-ocean ridges.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19990040666','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19990040666"><span>Wind Stress Forcing of the North Sea "Pole <span class="hlt">Tide</span>"</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>OConnor, William P.; Chao, Benjamin Fong; Zheng, Dawei; Au, Andrew Y.</p> <p>1998-01-01</p> <p>We conducted numerical simulations of the wind-forcing of the sea level variations in the North Sea using a barotropic ocean model with realistic geography, bathymetry, and boundary conditions, to examine the forcing of the 14-month "pole <span class="hlt">tide</span>" which is known to be strong along the Denmark- Netherlands coast. The simulation input is the monthly-mean surface wind stress field from the National Centers for Environmental Prediction (NCEP) reanalysis for the 40-year period 1958-1997. The output sea level response was then compared with 10 coastal <span class="hlt">tide</span> gauge records from the Permanent Service for Mean Sea Level (PSMSL). Besides the strong seasonal variations, several prominent quasi-periodicities exist at around 7 years, 3 years, 14 months, 9 months, and 6.5 months. Correlation and spectral analyses show remarkable agreement between the model output and the observations, particularly in the 14-month, or Chandler period band. The latter indicates that the enhanced pole <span class="hlt">tide</span> found in the North Sea along the Denmark-Netherlands coast is actually the coastal setup response to wind stress forcing with a periodicity of 14 months. We find no need to invoke a geophysical explanation involving resonance-enhancement of pole <span class="hlt">tide</span> in the North Sea to explain the observations.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/17111605','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/17111605"><span>[Mechanisms of removing red <span class="hlt">tide</span> organisms by organo-clays].</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Cao, Xi-Hua; Song, Xiu-Xian; Yu, Zhi-Ming; Wang, Kui</p> <p>2006-08-01</p> <p>We tested the influence of the preparation conditions of the quaternary ammonium compounds (QACs) modified clays on their capacities to remove red <span class="hlt">tide</span> organisms, then discussed the mechanisms of the organo-clays removing red <span class="hlt">tide</span> organisms. Hexadecyltrimethylammonium (HDTMA) improved the capacity of clays to flocculate red <span class="hlt">tide</span> algae, and the HDTMA in metastable state enhanced the toxicity of the clay complexes to algae. The capacities of the organo-clays correlated with the toxicity and the adsorbed amount of the QACs used in clays modification, but as the incubation time was prolonged the stability of the organo-clays was improved and the algal removal efficiencies of the clay complexes decreased. When the adsorbed HDTMA was arranged in different clays in which the spatial resistance was different, there was more HDTMA in metastable state in the three-layer montmorillonite. Because of the homo-ion effect the bivalent or trivalent metal ions induced more HDTMA in metastable state and the corresponding organo-clays had high capacities to remove red <span class="hlt">tide</span> organisms. When the reaction temperature was 60 degrees C the adsorbed HDTMA was easily arranged on cation exchange sites, if the temperature rose or fell the metastable HDTMA would increase so that the capacity of the clays was improved.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.fs.usda.gov/treesearch/pubs/22117','TREESEARCH'); return false;" href="https://www.fs.usda.gov/treesearch/pubs/22117"><span>Effect of <span class="hlt">weathering</span> <span class="hlt">variables</span> on the lightness of high-density polyethylene woodflour composites</span></a></p> <p><a target="_blank" href="http://www.fs.usda.gov/treesearch/">Treesearch</a></p> <p>Nicole M. Stark</p> <p>2005-01-01</p> <p>Wood-plastic lumber is promoted as a low-maintenance, high-durability product. After <span class="hlt">weathering</span>, however, wood-plastic composites (WPCs) often fade. In the first part of this study, 50 percent woodflour-filled high- density polyethylene (HDPE) composite samples were manufactured. Composites were exposed to two accelerated <span class="hlt">weathering</span> cycles in a xenon- arc type...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018GeoJI.tmp..205P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018GeoJI.tmp..205P"><span><span class="hlt">Tide</span> Gauge Records Reveal Improved Processing of Gravity Recovery and Climate Experiment Time-<span class="hlt">Variable</span> Mass Solutions over the Coastal Ocean</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Piecuch, Christopher G.; Landerer, Felix W.; Ponte, Rui M.</p> <p>2018-05-01</p> <p>Monthly ocean bottom pressure solutions from the Gravity Recovery and Climate Experiment (GRACE), derived using surface spherical cap mass concentration (MC) blocks and spherical harmonics (SH) basis functions, are compared to <span class="hlt">tide</span> gauge (TG) monthly averaged sea level data over 2003-2015 to evaluate improved gravimetric data processing methods near the coast. MC solutions can explain ≳ 42% of the monthly variance in TG time series over broad shelf regions and in semi-enclosed marginal seas. MC solutions also generally explain ˜5-32 % more TG data variance than SH estimates. Applying a coastline resolution improvement algorithm in the GRACE data processing leads to ˜ 31% more variance in TG records explained by the MC solution on average compared to not using this algorithm. Synthetic observations sampled from an ocean general circulation model exhibit similar patterns of correspondence between modeled TG and MC time series and differences between MC and SH time series in terms of their relationship with TG time series, suggesting that observational results here are generally consistent with expectations from ocean dynamics. This work demonstrates the improved quality of recent MC solutions compared to earlier SH estimates over the coastal ocean, and suggests that the MC solutions could be a useful tool for understanding contemporary coastal sea level <span class="hlt">variability</span> and change.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.usgs.gov/ds/2007/294/','USGSPUBS'); return false;" href="https://pubs.usgs.gov/ds/2007/294/"><span>Monitoring the Storm <span class="hlt">Tide</span> of Hurricane Wilma in Southwestern Florida, October 2005</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Soderqvist, Lars E.; Byrne, Michael J.</p> <p>2007-01-01</p> <p>Temporary monitoring stations employing non-vented pressure transducers were used to augment an existing U.S. Geological Survey coastal monitoring network to document the inland water levels related to the storm <span class="hlt">tide</span> of Hurricane Wilma on the southwestern coast of Florida. On October 22, 2005, an experimental network consisting of 30 temporary stations was deployed over 90 miles of coastline to record the magnitude, extent, and timing of hurricane storm <span class="hlt">tide</span> and coastal flooding. Sensors were programmed to record time, temperature, and barometric or water pressure. Water pressure was adjusted for changes in barometric pressure and salinity, and then converted to feet of water above the sensor. Elevation surveys using optical levels were conducted to reference storm <span class="hlt">tide</span> water-level data and high-water marks to the North American Vertical Datum of 1988 (NAVD 88). Storm <span class="hlt">tide</span> water levels more than 5 feet above NAVD 88 were recorded by sensors at several locations along the southwestern Florida coast. Temporary storm <span class="hlt">tide</span> monitoring stations used for this effort have demonstrated their value in: (1) furthering the understanding of storm <span class="hlt">tide</span> by allowing the U.S. Geological Survey to extend the scope of data collection beyond that of existing networks, and (2) serving as backup data collection at existing monitoring stations by utilizing nearby structures that are more likely to survive a major hurricane.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ars.usda.gov/research/publications/publication/?seqNo115=287290','TEKTRAN'); return false;" href="http://www.ars.usda.gov/research/publications/publication/?seqNo115=287290"><span>Using <span class="hlt">weather</span> data to improve decision-making</span></a></p> <p><a target="_blank" href="https://www.ars.usda.gov/research/publications/find-a-publication/">USDA-ARS?s Scientific Manuscript database</a></p> <p></p> <p></p> <p><span class="hlt">Weather</span> in the western United States is relatively dry and highly <span class="hlt">variable</span>. The consequences of this <span class="hlt">variability</span> can be effectively dealt with through the process of adaptive management which includes contingency planning for partial restoration success or restoration failure in any given year. Pr...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017SGeo...38.1097M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017SGeo...38.1097M"><span>Motional Induction by Tsunamis and Ocean <span class="hlt">Tides</span>: 10 Years of Progress</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Minami, Takuto</p> <p>2017-09-01</p> <p>Motional induction is the process by which the motion of conductive seawater in the ambient geomagnetic main field generates electromagnetic (EM) variations, which are observable on land, at the seafloor, and sometimes at satellite altitudes. Recent years have seen notable progress in our understanding of motional induction associated with tsunamis and with ocean <span class="hlt">tides</span>. New studies of tsunami motional induction were triggered by the 2004 Sumatra earthquake tsunami and further promoted by subsequent events, such as the 2010 Chile earthquake and the 2011 Tohoku earthquake. These events yielded observations of tsunami-generated EM variations from land and seafloor stations. Studies of magnetic fields generated by ocean <span class="hlt">tides</span> attracted interest when the Swarm satellite constellation enabled researchers to monitor <span class="hlt">tide</span>-generated magnetic variations from low Earth orbit. Both avenues of research benefited from the advent of sophisticated seafloor instruments, by which we may exploit motional induction for novel applications. For example, seafloor EM measurements can serve as detectors of vector properties of tsunamis, and seafloor EM data related to ocean <span class="hlt">tides</span> have proved useful for sounding Earth's deep interior. This paper reviews and discusses the progress made in motional induction studies associated with tsunamis and ocean <span class="hlt">tides</span> during the last decade.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20000116203','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20000116203"><span>Estimates of Internal <span class="hlt">Tide</span> Energy Fluxes from Topex/Poseidon Altimetry: Central North Pacific</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Ray, Richard D.; Cartwright, David E.; Smith, David E. (Technical Monitor)</p> <p>2000-01-01</p> <p>Energy fluxes for first-mode M(sub 2) internal <span class="hlt">tides</span> are deduced throughout the central North Pacific Ocean from Topex/Poseidon satellite altimeter data. Temporally coherent internal <span class="hlt">tide</span> signals in the altimetry, combined with climatological hydrographic data, determine the tidal displacements, pressures, and currents at depth, which yield power transmission rates. For a variety of reasons the deduced rates should be considered lower bounds. Internal <span class="hlt">tides</span> were found to emanate from several large bathymetric structures, especially the Hawaiian Ridge, where the integrated flux amounts to about six gigawatts. Internal <span class="hlt">tides</span> are generated at the Aleutian Trench near 172 deg west and propagate southwards nearly 2000 km.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017OcMod.113..145L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017OcMod.113..145L"><span>The K1 internal <span class="hlt">tide</span> simulated by a 1/10° OGCM</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Li, Zhuhua; von Storch, Jin-Song; Müller, Malte</p> <p>2017-05-01</p> <p>This paper quantifies the K1 internal <span class="hlt">tide</span> simulated by the 1/10° STORMTIDE model, which simultaneously resolves the eddying general circulation and <span class="hlt">tides</span>. An evident feature of the K1 internal <span class="hlt">tide</span> is the critical latitude φc at 30°, which in the STORMTIDE model is characterized by variations from a high energy level equatorward of 30° to a low energy level poleward of 30°. This critical latitude separates the internal <span class="hlt">tide</span> dynamics into bottom-trapped (at latitudes |φ| > |φc|) and freely propagating (at |φ| < |φc|) motions, respectively. Both types of motions are examined. The bottom-trapping process reveals a gradual vertical decrease of wave energy away from the bottom. The vertical scale, over which the wave energy decrease occurs, is smaller in shallow than in deep water regions. For the freely propagating K1 internal <span class="hlt">tides</span>, the STORMTIDE model is able to simulate the first three low modes, with the wavelengths ranging from 200-400 km, 100-200 km, to 60-120 km. These wavelength distributions reveal not only a zonal asymmetry but also a poleward increase up to φc, in particular in the Pacific. Such distributions indicate the impact of stratification N and the Coriolis frequency f on the wavelengths. The large wavelength gradient near φc is caused by the wavelength increase from finite values at subcritical latitudes to infinity at φc. Compared to the M2 internal <span class="hlt">tide</span>, the lower K1 tidal frequency leads to a stronger role of f, hence a weaker effect of N, for the K1 internal <span class="hlt">tide</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/20383268','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/20383268"><span>Changes in Work Habits of Lifeguards in Relation to Florida Red <span class="hlt">Tide</span>.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Nierenberg, Kate; Kirner, Karen; Hoagland, Porter; Ullmann, Steven; Leblanc, William G; Kirkpatrick, Gary; Fleming, Lora E; Kirkpatrick, Barbara</p> <p>2010-05-01</p> <p>The marine dinoflagellate, Karenia brevis, is responsible for Florida red <span class="hlt">tides</span>. Brevetoxins, the neurotoxins produced by K. brevis blooms, can cause fish kills, contaminate shellfish, and lead to respiratory illness in humans. Although several studies have assessed different economic impacts from Florida red <span class="hlt">tide</span> blooms, no studies to date have considered the impact on beach lifeguard work performance. Sarasota County experiences frequent Florida red <span class="hlt">tides</span> and staffs lifeguards at its beaches 365 days a year. This study examined lifeguard attendance records during the time periods of March 1 to September 30 in 2004 (no bloom) and March 1 to September 30 in 2005 (bloom). The lifeguard attendance data demonstrated statistically significant absenteeism during a Florida red <span class="hlt">tide</span> bloom. The potential economic costs resulting from red <span class="hlt">tide</span> blooms were comprised of both lifeguard absenteeism and presenteeism. Our estimate of the costs of absenteeism due to the 2005 red <span class="hlt">tide</span> in Sarasota County is about $3,000. On average, the capitalized costs of lifeguard absenteeism in Sarasota County may be on the order of $100,000 at Sarasota County beaches alone. When surveyed, lifeguards reported not only that they experienced adverse health effects of exposure to Florida red <span class="hlt">tide</span> but also that their attentiveness and abilities to take preventative actions decrease when they worked during a bloom, implying presenteeism effects. The costs of presenteeism, which imply increased risks to beachgoers, arguably could exceed those of absenteeism by an order of magnitude. Due to the lack of data, however, we are unable to provide credible estimates of the costs of presenteeism or the potential increased risks to bathers.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://eric.ed.gov/?q=Influence+AND+cloud+AND+climate&id=ED204158','ERIC'); return false;" href="https://eric.ed.gov/?q=Influence+AND+cloud+AND+climate&id=ED204158"><span><span class="hlt">Weather</span>, Climate, and You.</span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Blai, Boris, Jr.</p> <p></p> <p>Information from the American Institute of Medical Climatologists on human responses to <span class="hlt">weather</span> and climatic conditions, including clouds, winds, humidity, barometric pressure, heat, cold, and other <span class="hlt">variables</span> that may exert a pervasive impact on health, behavior, disposition, and the level of efficiency with which individuals function is reviewed.…</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/24563634','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/24563634"><span>Florida Red <span class="hlt">Tide</span> Knowledge and Risk Perception: Is there a need for tailored messaging?</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Kirkpatrick, Barbara; Kohler, Kate; Byrne, Margaret M; Studts, Jamie</p> <p>2014-02-01</p> <p>Harmful algal blooms of the toxic dinoflagellate, Karenia brevis , occur throughout the Gulf of Mexico. Recent research efforts sponsored by the National Institute of Environmental Health Sciences (NIEHS) and others found that Florida red <span class="hlt">tide</span> causes both acute and possibly chronic health effects from the toxic aerosols. Florida red <span class="hlt">tide</span> also demonstrated significant social and economic impacts to both coastal residents and visitors. In conjunction with the research, persistent outreach efforts were conducted over the 11 year period. The goal of this project was to assess potential needs for tailored messaging needed among different red <span class="hlt">tide</span> information user groups. Survey participants included 303 local residents, both with asthma and without, and 'snowbirds (seasonal residents that reside in the Sarasota area for more than 3 months but less than 6 months/year), also both with asthma and without. The questionnaire assessed Florida red <span class="hlt">tide</span> knowledge and risk perception regarding Florida red <span class="hlt">tide</span> using items drawn from two previously published surveys to allow comparison. Our results reveal that overall knowledge of Florida red <span class="hlt">tide</span> has not changed. We found that knowledge was consistent across our selected groups and also did not vary by age, gender and education level. However, knowledge regarding consumption of seafood during Florida red <span class="hlt">tide</span> has declined. Risk perception increased significantly for people who have asthma. Individuals responsible for public health communication regarding Florida red <span class="hlt">tide</span> and human health concerns need to continue to pursue more effective outreach messages and delivery methods.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3927915','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3927915"><span>Florida Red <span class="hlt">Tide</span> Knowledge and Risk Perception: Is there a need for tailored messaging?</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Kirkpatrick, Barbara; Kohler, Kate; Byrne, Margaret M.; Studts, Jamie</p> <p>2013-01-01</p> <p>Harmful algal blooms of the toxic dinoflagellate, Karenia brevis, occur throughout the Gulf of Mexico. Recent research efforts sponsored by the National Institute of Environmental Health Sciences (NIEHS) and others found that Florida red <span class="hlt">tide</span> causes both acute and possibly chronic health effects from the toxic aerosols. Florida red <span class="hlt">tide</span> also demonstrated significant social and economic impacts to both coastal residents and visitors. In conjunction with the research, persistent outreach efforts were conducted over the 11 year period. The goal of this project was to assess potential needs for tailored messaging needed among different red <span class="hlt">tide</span> information user groups. Survey participants included 303 local residents, both with asthma and without, and ‘snowbirds (seasonal residents that reside in the Sarasota area for more than 3 months but less than 6 months/year), also both with asthma and without. The questionnaire assessed Florida red <span class="hlt">tide</span> knowledge and risk perception regarding Florida red <span class="hlt">tide</span> using items drawn from two previously published surveys to allow comparison. Our results reveal that overall knowledge of Florida red <span class="hlt">tide</span> has not changed. We found that knowledge was consistent across our selected groups and also did not vary by age, gender and education level. However, knowledge regarding consumption of seafood during Florida red <span class="hlt">tide</span> has declined. Risk perception increased significantly for people who have asthma. Individuals responsible for public health communication regarding Florida red <span class="hlt">tide</span> and human health concerns need to continue to pursue more effective outreach messages and delivery methods. PMID:24563634</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013ESASP.710E...9E','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013ESASP.710E...9E"><span>Twenty Years of Progress on Global Ocean <span class="hlt">Tide</span>: The Impact of Satellite Altimetry</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Egbert, Gary D.; Ray, Richard D.</p> <p>2013-09-01</p> <p>At the dawn of the era of high-precision altimetry, before the launch of TOPEX/Poseidon, ocean <span class="hlt">tides</span> were properly viewed as a source of noise-tidal variations in ocean height would represent a very substantial fraction of what the altimeter measures, and would have to be accurately predicted and subtracted if altimetry were to achieve its potential for ocean and climate studies. But to the extent that the altimetry could be severely contaminated by <span class="hlt">tides</span>, it also represented an unprecedented global-scale tidal data set. These new data, together with research stimulated by the need for accurate tidal corrections, led to a renaissance in tidal studies in the oceanographic community. In this paper we review contributions of altimetry to tidal science over the past 20 years, emphasizing recent progress. Mapping of <span class="hlt">tides</span> has now been extended from the early focus on major constituents in the open ocean to include minor constituents, (e.g., long-period <span class="hlt">tides</span>; non-linear <span class="hlt">tides</span> in shelf waters, and in the open ocean), and into shallow and coastal waters. Global and spatially local estimates of tidal energy balance have been refined, and the role of internal <span class="hlt">tide</span> conversion in dissipating barotropic tidal energy is now well established through modeling, altimetry, and in situ observations. However, energy budgets for internal <span class="hlt">tides</span>, and the role of tidal dissipation in vertical ocean mixing remain controversial topics. Altimetry may contribute to resolving some of these important questions through improved mapping of low-mode internal <span class="hlt">tides</span>. This area has advanced significantly in recent years, with several global maps now available, and progress on constraining temporally incoherent components. For the future, new applications of altimetry (e.g., in the coastal ocean, where barotropic tidal models remain inadequate), and new mission concepts (studies of the sub-mesoscale with SWOT, which will require correction for internal <span class="hlt">tides</span>) may bring us full circle, again pushing</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20120009634','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20120009634"><span>Twenty Years of Progress on Global Ocean <span class="hlt">Tides</span>: The Impact of Satellite Altimetry</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Egbert, Gary; Ray, Richard</p> <p>2012-01-01</p> <p>At the dawn of the era of high-precision altimetry, before the launch of TOPEX/Poseidon, ocean <span class="hlt">tides</span> were properly viewed as a source of noise--tidal variations in ocean height would represent a very substantial fraction of what the altimeter measures, and would have to be accurately predicted and subtracted if altimetry were to achieve its potential for ocean and climate studies. But to the extent that the altimetry could be severely contaminated by <span class="hlt">tides</span>, it also represented an unprecedented global-scale tidal data set. These new data, together with research stimulated by the need for accurate tidal corrections, led to a renaissance in tidal studies in the oceanographic community. In this paper we review contributions of altimetry to tidal science over the past 20 years, emphasizing recent progress. Mapping of <span class="hlt">tides</span> has now been extended from the early focus on major constituents in the open ocean to include minor constituents, (e.g., long-period <span class="hlt">tides</span>; non-linear <span class="hlt">tides</span> in shelf waters, and in the open ocean), and into shallow and coastal waters. Global and spatially local estimates of tidal energy balance have been refined, and the role of internal <span class="hlt">tide</span> conversion in dissipating barotropic tidal energy is now well established through modeling, altimetry, and in situ observations. However, energy budgets for internal <span class="hlt">tides</span>, and the role of tidal dissipation in vertical ocean mixing remain controversial topics. Altimetry may contribute to resolving some of these important questions through improved mapping of low-mode internal <span class="hlt">tides</span>. This area has advanced significantly in recent years, with several global maps now available, and progress on constraining temporally incoherent components. For the future, new applications of altimetry (e.g., in the coastal ocean, where barotropic tidal models remain inadequate), and new mission concepts (studies of the submesoscale with SWOT, which will require correction for internal <span class="hlt">tides</span>) may bring us full circle, again pushing</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2010EGUGA..1212253A','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2010EGUGA..1212253A"><span>Analysis of the most recent data of Cascais <span class="hlt">Tide</span> Gauge</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Antunes, Carlos; Taborda, Rui; Mendes, Virgílio B.</p> <p>2010-05-01</p> <p>In order to meet international standards and to integrate sea level changes and tsunami monitoring networks, Cascais <span class="hlt">tide</span> gauge, one of the oldest in the world, has been upgraded in 2003 with new acoustic equipment with digital data acquisition, temperature and air-pressure sensors, and internet connection for real time data. The new <span class="hlt">tide</span> gauge is located very close to the old analogical gauge, which is still working. Datum links between both gauges and the permanent GPS station of Cascais were made and height differences between gauges and the GPS station have been monitored to verify site stability and to estimate the absolute vertical velocity of the site, and therefore, the absolute sea level changes. <span class="hlt">Tide</span> gauge data from 2000 to 2009 has been analyzed and relative and absolute sea level rise rates have been estimated. The estimation of sea level rise rate with the short baseline of 10 years is made with the daily mean sea level data corrected from the inverse barometric effect. The relative sea level trend is obtained from a 60-day moving average run over the corrected daily mean sea level. The estimated rate has shown greater stability in contrast to the analysis of daily mean sea level raw data, which shows greater <span class="hlt">variability</span> and uncertainty. Our results show a sea level rise rate of 2.6 mm/year (± 0.3 mm/year), higher than previous rates (2.1 mm/year for 1990 decade and 1.6 mm/year from 1920 to 2000), which is compatible with a sea level rise acceleration scenario. From the analysis of Cascais GPS data, for the period 1990.0 to 2010.0 we obtain an uplift rate of 0.3 mm/year leading to an absolute sea level rise of 2.9 mm/year for Cascais, under the assumption, as predicted by the ICE-5G model, that Cascais has no vertical displacement caused by the post-glacial isostatic adjustment.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li class="active"><span>19</span></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_19 --> <div id="page_20" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li class="active"><span>20</span></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="381"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.dtic.mil/docs/citations/ADA569864','DTIC-ST'); return false;" href="http://www.dtic.mil/docs/citations/ADA569864"><span>Inferring Dynamics from the Wavenumber Spectra of an Eddying Global Ocean Model with Embedded <span class="hlt">Tides</span></span></a></p> <p><a target="_blank" href="http://www.dtic.mil/">DTIC Science & Technology</a></p> <p></p> <p>2012-12-12</p> <p>MODEL WAVENUMBER SPECTRA (12(112 Ocean Model (HYCOM) [Chassignet et al., 2007 ; Metzger et al., 2010] with 1/12.5° (approximately 9 km) equatorial...Chassignet, E. P., H. E. Ilurlburt. O. M. Smedstad, G. R. Halliwcll, P. J. Hogan, A. J. Wallcraft, R. Baraille. and R. Bleck ( 2007 ), The HYCOM (HYbrid...<span class="hlt">tide</span> models, J. Geophys. Res., 102, 25,173 25,194, doi:10.1029/97JC00445. Stammer , D. (1997), Global characteristics of ocean <span class="hlt">variability</span> estimated</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/22007423','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/22007423"><span>[Retrieve of red <span class="hlt">tide</span> distributions from MODIS data based on the characteristics of water spectrum].</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Qiu, Zhong-Feng; Cui, Ting-Wei; He, Yi-Jun</p> <p>2011-08-01</p> <p>After comparing the spectral differences between red <span class="hlt">tide</span> water and normal water, we developed a method to retrieve red <span class="hlt">tide</span> distributions from MODIS data based on the characteristics of red <span class="hlt">tide</span> water spectrum. The authors used the 119 series of in situ observations to validate the method and found that only one observation has not been detected correctly. The authors then applied this method to MODIS data on April 4, 2005. In the research areas three locations of red <span class="hlt">tide</span> water were apparently detected with the total areas about 2 000 km2. The retrieved red <span class="hlt">tide</span> distributions are in good agreement with the distributions of high chlorophyll a concentrations. The research suggests that the method is available to eliminating the influence of suspended sediments and can be used to retrieve the locations and areas of red <span class="hlt">tide</span> water.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.usgs.gov/sir/2013/5076/pdf/sir2013-5076_report_508.pdf','USGSPUBS'); return false;" href="https://pubs.usgs.gov/sir/2013/5076/pdf/sir2013-5076_report_508.pdf"><span>A one-dimensional diffusion analogy model for estimation of <span class="hlt">tide</span> heights in selected tidal marshes in Connecticut</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Bjerklie, David M.; O’Brien, Kevin; Rozsa, Ron</p> <p>2013-01-01</p> <p>A one-dimensional diffusion analogy model for estimating <span class="hlt">tide</span> heights in coastal marshes was developed and calibrated by using data from previous tidal-marsh studies. The method is simpler to use than other one- and two-dimensional hydrodynamic models because it does not require marsh depth and tidal prism information; however, the one-dimensional diffusion analogy model cannot be used to estimate <span class="hlt">tide</span> heights, flow velocities, and <span class="hlt">tide</span> arrival times for <span class="hlt">tide</span> conditions other than the highest <span class="hlt">tide</span> for which it is calibrated. Limited validation of the method indicates that it has an accuracy within 0.3 feet. The method can be applied with limited calibration information that is based entirely on remote sensing or geographic information system data layers. The method can be used to estimate high-<span class="hlt">tide</span> heights in tidal wetlands drained by <span class="hlt">tide</span> gates where <span class="hlt">tide</span> levels cannot be observed directly by opening the gates without risk of flooding properties and structures. A geographic information system application of the method is demonstrated for Sybil Creek marsh in Branford, Connecticut. The tidal flux into this marsh is controlled by two <span class="hlt">tide</span> gates that prevent full tidal inundation of the marsh. The method application shows reasonable <span class="hlt">tide</span> heights for the gates-closed condition (the normal condition) and the one-gate-open condition on the basis of comparison with observed heights. The condition with all <span class="hlt">tide</span> gates open (two gates) was simulated with the model; results indicate where several structures would be flooded if the gates were removed as part of restoration efforts or if the <span class="hlt">tide</span> gates were to fail.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017DSRI..126...73H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017DSRI..126...73H"><span>Partly standing internal <span class="hlt">tides</span> in a dendritic submarine canyon observed by an ocean glider</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Hall, Rob A.; Aslam, Tahmeena; Huvenne, Veerle A. I.</p> <p>2017-08-01</p> <p>An autonomous ocean glider is used to make the first direct measurements of internal <span class="hlt">tides</span> within Whittard Canyon, a large, dendritic submarine canyon system that incises the Celtic Sea continental slope and a site of high benthic biodiversity. This is the first time a glider has been used for targeted observations of internal <span class="hlt">tides</span> in a submarine canyon. Vertical isopycnal displacement observations at different stations fit a one-dimensional model of partly standing semidiurnal internal <span class="hlt">tides</span> - comprised of a major, incident wave propagating up the canyon limbs and a minor wave reflected back down-canyon by steep, supercritical bathymetry near the canyon heads. The up-canyon internal <span class="hlt">tide</span> energy flux in the primary study limb decreases from 9.2 to 2.0 kW m-1 over 28 km (a dissipation rate of 1 - 2.5 ×10-7 Wkg-1), comparable to elevated energy fluxes and internal <span class="hlt">tide</span> driven mixing measured in other canyon systems. Within Whittard Canyon, enhanced mixing is inferred from collapsed temperature-salinity curves and weakened dissolved oxygen concentration gradients near the canyon heads. It has previously been hypothesised that internal <span class="hlt">tides</span> impact benthic fauna through elevated near-bottom current velocities and particle resuspension. In support of this, we infer order 20 cm s-1 near-bottom current velocities in the canyon and observe high concentrations of suspended particulate matter. The glider observations are also used to estimate a 1 °C temperature range and 12 μmol kg-1 dissolved oxygen concentration range, experienced twice a day by organisms on the canyon walls, due to the presence of internal <span class="hlt">tides</span>. This study highlights how a well-designed glider mission, incorporating a series of <span class="hlt">tide</span>-resolving stations at key locations, can be used to understand internal <span class="hlt">tide</span> dynamics in a region of complex topography, a sampling strategy that is applicable to continental shelves and slopes worldwide.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018JGRE..123..335T','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018JGRE..123..335T"><span>Three-Dimensional Structures of Thermal <span class="hlt">Tides</span> Simulated by a Venus GCM</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Takagi, Masahiro; Sugimoto, Norihiko; Ando, Hiroki; Matsuda, Yoshihisa</p> <p>2018-02-01</p> <p>Thermal <span class="hlt">tides</span> in the Venus atmosphere are investigated by using a GCM named as AFES-Venus. The three-dimensional structures of wind and temperature associated with the thermal <span class="hlt">tides</span> obtained in our model are fully examined and compared with observations. The result shows that the wind and temperature distributions of the thermal <span class="hlt">tides</span> depend complexly on latitude and altitude in the cloud layer, mainly because they consist of vertically propagating and trapped modes with zonal wave numbers of 1-4, each of which predominates in different latitudes and altitudes under the influence of mid- and high-latitude jets. A strong circulation between the subsolar and antisolar (SS-AS) points, which is equivalent to a diurnal component of the thermal <span class="hlt">tides</span>, is superposed on the superrotation. The vertical velocity of SS-AS circulation is about 10 times larger than that of the zonal-mean meridional circulation (ZMMC) in 60-70 km altitudes. It is suggested that the SS-AS circulation could contribute to the material transport, and its upward motion might be related to the UV dark region observed in the subsolar and early afternoon regions in low latitudes. The terdiurnal and quaterdiurnal <span class="hlt">tides</span>, which may be excited by the nonlinear interactions among the diurnal and semidiurnal <span class="hlt">tides</span> in middle and high latitudes, are detected in the solar-fixed Y-shape structure formed in the vertical wind field in the upper cloud layer. The ZMMC is weak and has a complex structure in the cloud layer; the Hadley circulation is confined to latitudes equatorward of 30°, and the Ferrel-like one appears in middle and high latitudes.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013IJBm...57..845C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013IJBm...57..845C"><span>Seasonal variation, <span class="hlt">weather</span> and behavior in day-care children: a multilevel approach</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Ciucci, Enrica; Calussi, Pamela; Menesini, Ersilia; Mattei, Alessandra; Petralli, Martina; Orlandini, Simone</p> <p>2013-11-01</p> <p>This study analyzes the effect of <span class="hlt">weather</span> <span class="hlt">variables</span>, such as solar radiation, indoor and outdoor air temperature, relative humidity and time spent outdoor, on the behavior of 2-year-old children and their affects across different seasons: winter, spring and summer. Participants were a group of 61 children (33 males and 28 females) attending four day-care centers in Florence (Central Italy). Mean age of children at the beginning of the study was 24.1 months ( SD = 3.6). We used multilevel linear analyses to account for the hierarchical structure of our data. The study analyzed the following behavioral <span class="hlt">variables</span>: Activity Level, Attentional Focusing, Frustration, and Aggression. Results showed a different impact of some <span class="hlt">weather</span> <span class="hlt">variables</span> on children’s behavior across seasons, indicating that the <span class="hlt">weather</span> <span class="hlt">variable</span> that affects children’s behavior is usually the one that shows extreme values during the studied seasons, such as air temperature and relative humidity in winter and summer. Studying children and their reactions to <span class="hlt">weather</span> conditions could have potentially wide-reaching implications for parenting and teaching practices, as well as for researchers studying social relationships development.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3231327','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3231327"><span>Time-Frequency Analyses of <span class="hlt">Tide</span>-Gauge Sensor Data</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Erol, Serdar</p> <p>2011-01-01</p> <p>The real world phenomena being observed by sensors are generally non-stationary in nature. The classical linear techniques for analysis and modeling natural time-series observations are inefficient and should be replaced by non-linear techniques of whose theoretical aspects and performances are varied. In this manner adopting the most appropriate technique and strategy is essential in evaluating sensors’ data. In this study, two different time-series analysis approaches, namely least squares spectral analysis (LSSA) and wavelet analysis (continuous wavelet transform, cross wavelet transform and wavelet coherence algorithms as extensions of wavelet analysis), are applied to sea-level observations recorded by <span class="hlt">tide</span>-gauge sensors, and the advantages and drawbacks of these methods are reviewed. The analyses were carried out using sea-level observations recorded at the Antalya-II and Erdek <span class="hlt">tide</span>-gauge stations of the Turkish National Sea-Level Monitoring System. In the analyses, the useful information hidden in the noisy signals was detected, and the common features between the two sea-level time series were clarified. The <span class="hlt">tide</span>-gauge records have data gaps in time because of issues such as instrumental shortcomings and power outages. Concerning the difficulties of the time-frequency analysis of data with voids, the sea-level observations were preprocessed, and the missing parts were predicted using the neural network method prior to the analysis. In conclusion the merits and limitations of the techniques in evaluating non-stationary observations by means of <span class="hlt">tide</span>-gauge sensors records were documented and an analysis strategy for the sequential sensors observations was presented. PMID:22163829</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/22163829','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/22163829"><span>Time-frequency analyses of <span class="hlt">tide</span>-gauge sensor data.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Erol, Serdar</p> <p>2011-01-01</p> <p>The real world phenomena being observed by sensors are generally non-stationary in nature. The classical linear techniques for analysis and modeling natural time-series observations are inefficient and should be replaced by non-linear techniques of whose theoretical aspects and performances are varied. In this manner adopting the most appropriate technique and strategy is essential in evaluating sensors' data. In this study, two different time-series analysis approaches, namely least squares spectral analysis (LSSA) and wavelet analysis (continuous wavelet transform, cross wavelet transform and wavelet coherence algorithms as extensions of wavelet analysis), are applied to sea-level observations recorded by <span class="hlt">tide</span>-gauge sensors, and the advantages and drawbacks of these methods are reviewed. The analyses were carried out using sea-level observations recorded at the Antalya-II and Erdek <span class="hlt">tide</span>-gauge stations of the Turkish National Sea-Level Monitoring System. In the analyses, the useful information hidden in the noisy signals was detected, and the common features between the two sea-level time series were clarified. The <span class="hlt">tide</span>-gauge records have data gaps in time because of issues such as instrumental shortcomings and power outages. Concerning the difficulties of the time-frequency analysis of data with voids, the sea-level observations were preprocessed, and the missing parts were predicted using the neural network method prior to the analysis. In conclusion the merits and limitations of the techniques in evaluating non-stationary observations by means of <span class="hlt">tide</span>-gauge sensors records were documented and an analysis strategy for the sequential sensors observations was presented.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012AGUFMED22C..02V','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012AGUFMED22C..02V"><span>Exploring Marine Science through the University of Delaware's <span class="hlt">TIDE</span> camp</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Veron, D. E.; Newton, F. A.; Veron, F.; Trembanis, A. C.; Miller, D. C.</p> <p>2012-12-01</p> <p>For the past five years, the University of Delaware has offered a two-week, residential, summer camp to rising sophomores, juniors, and seniors who are interested in marine science. The camp, named <span class="hlt">TIDE</span> (Taking an Interest in Delaware's Estuary) camp, is designed to introduce students to the breadth of marine science while providing them with a college experience. Campers participate in a variety of academic activities which include classroom, laboratory, and field experiences, as well as numerous social activities. Two unique features of this small, focused camp is the large number of university faculty that are involved, and the ability of students to participate in ongoing research projects. At various times students have participated in fish and dolphin counts, AUV deployment, wind-wave tank experiments, coastal water and beach studies, and ROV activities. In addition, each year campers have participated in a local service project. Through communication with former <span class="hlt">TIDE</span> participants, it is clear that this two-week, formative experience plays a large role in students choice of major when entering college.2012 <span class="hlt">Tide</span> Camp - Salt marsh in southern Delaware 2012 <span class="hlt">Tide</span> Camp - Field trip on a small boat</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ars.usda.gov/research/publications/publication/?seqNo115=259621','TEKTRAN'); return false;" href="http://www.ars.usda.gov/research/publications/publication/?seqNo115=259621"><span><span class="hlt">Weather</span> and climate applications for rangeland restoration planning</span></a></p> <p><a target="_blank" href="https://www.ars.usda.gov/research/publications/find-a-publication/">USDA-ARS?s Scientific Manuscript database</a></p> <p></p> <p></p> <p>Rangeland ecosystems generally have an arid or semi-arid climatology, and are characterized by relatively high <span class="hlt">variability</span> in seasonal and annual patterns of precipitation. <span class="hlt">Weather</span> <span class="hlt">variability</span> during seedling establishment is universally acknowledged as a principal determinant of rangeland seeding...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/26775001','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/26775001"><span>Environmental <span class="hlt">variables</span> associated with vacationers' sun protection at warm <span class="hlt">weather</span> resorts in North America.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Andersen, Peter A; Buller, David B; Walkosz, Barbara J; Scott, Michael D; Beck, Larry; Liu, Xia; Abbott, Allison; Eye, Rachel</p> <p>2016-04-01</p> <p>Vacationing at sunny, warm <span class="hlt">weather</span> locations is a risk factor for excessive solar ultraviolet (UV) radiation exposure and skin cancer. This study examined the association of environmental <span class="hlt">variables</span> related to UV levels with vacationers' sun protection. Vacationers at 41 summer resorts in 17 states and 1 Canadian Province were interviewed (n=3531) and observed (N=4347) during 2012 and 2013. Clothing coverage, sunglasses, and shade use were observed. Use of sunscreen and sunburns were self-reported. Environmental information was recorded by research staff or acquired from ground stations and the <span class="hlt">weather</span> service. Temperature was positively associated with sun protection behaviors; however clothing coverage was negatively associated with temperature. Cloud cover was negatively associated with sun protection, with the exception of clothing coverage which was positively associated with it. Elevation showed a mixed pattern of associations with vacationer's sun protection. Latitude of a resort was negatively associated with most sun protection behaviors, such that sun protection increased at more southerly resorts. Similarly, the farther south a vacationer traveled to the resort, the less sun protection they employed. The UV index showed a weak, positive relationship with some sun protection behaviors even when controlling for temperature. Vacationers appeared aware that UV is higher at southern latitudes and may learn UV is intense when living in southern regions. However, many used temperature, an unreliable cue, to judge UV intensity and seemed to adjust clothing for warmth not UV protection. Efforts are needed to help individuals make more accurate sun safety decisions. Copyright © 2016. Published by Elsevier Inc.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017EGUGA..1910769K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017EGUGA..1910769K"><span>A Plan to Develop a Red <span class="hlt">Tide</span> Warning System for Seawater Desalination Process Management</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Kim, Tae Woo; Yun, Hong Sik</p> <p>2017-04-01</p> <p>The holt of the seawater desalination process for fifty five days due to the eight-month long red <span class="hlt">tide</span> in 2008 in the Persian Gulf, the Middle East, had lost about 10 billion KRW. The POSCO Seawater Desalination facility, located in Gwangyang Bay Area in the Southern Sea, has produced 30,000 tons of fresh water per day since 2014. Since there has been an incident of red time in the area for three months in August, 2012, it is necessary to establish a warning system for red <span class="hlt">tide</span> that threatens the stable operation of the seawater desalination facility. A red <span class="hlt">tide</span> warning system can offer the seawater desalination facility manager customized services on red <span class="hlt">tide</span> information and potential red <span class="hlt">tide</span> inflow to the water intake. This study aimed to develop a red <span class="hlt">tide</span> warning system in Gwangyang Bay Area by combining RS, modeling and monitoring technologies, which provides red <span class="hlt">tide</span> forecasting information with which to effectively control the seawater desalination process. Using the proposed system, the seawater desalination facility manager can take phased measures to cope with the inflow of red <span class="hlt">tide</span>. ACKNOWLEDGMENTS This research was supported by a grant(16IFIP-C088924-03) from Industrial Facilities & Infrastructure Research Program funded by Ministry of Land, Infrastructure and Transport(MOLIT) of the Korea government and the Korea Agency for Infrastructure Technology Advancement (KAIA). This research was supported by Basic Science Research Program through the National Research Foundation of Korea(NRF) funded by the Ministry of Education(NRF-2014R1A1A2054975).</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=20170002390&hterms=churchill&qs=N%3D0%26Ntk%3DAll%26Ntx%3Dmode%2Bmatchall%26Ntt%3Dchurchill','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=20170002390&hterms=churchill&qs=N%3D0%26Ntk%3DAll%26Ntx%3Dmode%2Bmatchall%26Ntt%3Dchurchill"><span>On Measurements of the <span class="hlt">Tide</span> at Churchill, Hudson Bay</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Ray, Richard D.</p> <p>2016-01-01</p> <p>Since the late 1990s the semi-diurnal <span class="hlt">tide</span> at Churchill, on the western shore of Hudson Bay, has been decreasing in amplitude, with M(sub 2) amplitudes falling from approximately 154 cm in 1998 to 146 cm in 2012 and 142 cm in 2014. There has been a corresponding small increase in phase lag. Mean low water, decreasing throughout most of the twentieth century, has levelled off. Although the tidal changes could reflect merely a malfunctioning <span class="hlt">tide</span> gauge, the fact that there are no other measurements in the region and the possibility that the <span class="hlt">tide</span> is revealing important environmental changes calls for serious investigation. Satellite altimeter measurements of the <span class="hlt">tide</span> in Hudson Bay are complicated by the seasonal ice cover; at most locations less than 40% of satellite passes return valid ocean heights and even those can be impacted by errors from sea ice. Because the combined TOPEX/Poseidon, Jason-1, and Jason-2 time series is more than 23 years long, it is now possible to obtain sufficient data at crossover locations near Churchill to search for tidal changes. The satellites sense no changes in M(sub 2) that are comparable to the changes seen at the Churchill gauge. The changes appear to be localized to the harbour, or to the Churchill River, or to the gauge itself.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20150008269','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20150008269"><span>Thermal <span class="hlt">Tides</span> During the 2001 Martian Global-Scale Dust Storm</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Guzewich, Scott D.; Wilson, R. John; McConnochie, Timothy H.; Toigo, Anthony D.; Bandfield, Donald J.; Smith, Michael D.</p> <p>2014-01-01</p> <p>The 2001 (Mars Year 25) global dust storm radically altered the dynamics of the Martian atmosphere. Using observations from the Thermal Emission Spectrometer onboard the Mars Global Surveyor spacecraft and Mars WRF general circulation model simulations, we examine the changes to thermal <span class="hlt">tides</span> and planetary waves caused by the storm. We find that the extratropical diurnal migrating <span class="hlt">tide</span> is dramatically enhanced during the storm, particularly in the southern hemisphere, reaching amplitudes of more than 20 K. The tropical diurnal migrating <span class="hlt">tide</span> is weakened to almost undetectable levels. The diurnal Kelvin waves are also significantly weakened, particularly during the period of global expansion at Ls=200deg-210deg. In contrast, the westward propagating diurnal wavenumber 2 <span class="hlt">tide</span> strengthens to 4-8 K at altitudes above 30km. The wavenumber 1 stationary wave reaches amplitudes of 10-12 K at 50deg-70degN, far larger than is typically seen during this time of year. The phase of this stationary wave and the enhancement of the diurnal wavenumber 2 <span class="hlt">tide</span> appear to be responses to the high-altitude westward propagating equatorial wavenumber 1 structure in dust mixing ratio observed during the storm in previous works. This work provides a global picture of dust storm wave dynamics that reveals the coupling between the tropics and high-latitude wave responses. We conclude that the zonal distribution of thermotidal forcing from atmospheric aerosol concentration is as important to understanding the atmospheric wave response as the total global mean aerosol optical depth.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2010EGUGA..12.7145R','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2010EGUGA..12.7145R"><span>Linking storm surge activity and circulation <span class="hlt">variability</span> along the Spanish coast through a synoptic pattern classification</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Rasilla Álvarez, Domingo; Garcia Codrón, Juan Carlos</p> <p>2010-05-01</p> <p>://www.cdc.noaa.gov/map/clim/st_data.html). The second task was to evaluate the performance of each circulation type on the spatial patterns of a daily fire danger risk index (Canadian Fire <span class="hlt">Weather</span> Index, FWI). Finally, anomaly maps of several surface and low level climate <span class="hlt">variables</span>, corresponding to the dates of ignition of the very large forest fires within each synoptic pattern, were calculated to provide insight of the specific conditions associated to those extreme events. A principal component analysis upon 6 hourly residuals highlighted the homogeneous behaviour of the <span class="hlt">tide</span> gauges and provided a regional quantitative index to identify the largest storm surges. The leading PCA displayed a homogeneous spatial pattern, describing the low frequency <span class="hlt">variability</span> along the entire coast, in spite of different orientations of the coast, accounting for more than 80% of the total <span class="hlt">variability</span>. The second PCA displayed opposite phases between the Atlantic and the Mediterranean. Furthermore, the results suggest that surges are a regional rather than local phenomenon, probably related to the same single physical forcing. The comparison between extreme surge events and circulation patterns highlighted that single physical mechanism is represented by extratropical cyclonic disturbances located at the north-western corner of the Iberian Peninsula, responsible for an environment characterized by low pressure readings and westerly-southwesterly winds. That wind pattern acquires an onshore component in the Atlantic coast, but becomes offshore in the Mediterranean. So, the main mechanism responsible for those storm surges is the inverse barometer effect, being the wind dragging secondary. The main physical forcing of the storm surges, the extratropical cyclones, have experience a reduction of this frequency and a marked reduction in their strength since 1950, replaced by stable circulations. Both conditions suggest a long term reduction of the frequency and the magnitude of storm surges.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/14587353','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/14587353"><span>[Algorithms of multiband remote sensing for coastal red <span class="hlt">tide</span> waters].</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Mao, Xianmou; Huang, Weigen</p> <p>2003-07-01</p> <p>The spectral characteristics of the coastal waters in East China Sea was studied using in situ measurements, and the multiband algorithms of remote sensing for bloom waters was discussed and developed. Examples of red <span class="hlt">tide</span> detection using the algorithms in the East China Sea were presented. The results showed that the algorithms could provide information about the location and the area coverage of the red <span class="hlt">tide</span> events.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=20060036711&hterms=oceans+tide&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3Doceans%2Btide','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=20060036711&hterms=oceans+tide&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3Doceans%2Btide"><span>Effects of Long Period Ocean <span class="hlt">Tides</span> on the Earth's Rotation</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Gross, Richard S.; Chao, Ben F.; Desai, Shailen D.</p> <p>1996-01-01</p> <p>The spectra of polar motion excitation functions exhibit enhanced power in the fortnightly tidal band. This enhanced power is attributed to ocean tidal excitation. Ocean <span class="hlt">tide</span> models predict polar motion excitation effects that differ with each other, and with observations, by factors as large as 2-3. There is a need for inproved models for the effect of long-period ocean <span class="hlt">tides</span> on Earth's rotation.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017GeoRL..4411942Z','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017GeoRL..4411942Z"><span>Propagation of the Semidiurnal Internal <span class="hlt">Tide</span>: Phase Velocity Versus Group Velocity</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Zhao, Zhongxiang</p> <p>2017-12-01</p> <p>The superposition of two waves of slightly different wavelengths has long been used to illustrate the distinction between phase velocity and group velocity. The first-mode M2 and S2 internal <span class="hlt">tides</span> exemplify such a two-wave model in the natural ocean. The M2 and S2 tidal frequencies are 1.932 and 2 cycles per day, respectively, and their superposition forms a spring-neap cycle in the semidiurnal band. The spring-neap cycle acts like a wave, with its frequency, wave number, and phase being the differences of the M2 and S2 internal <span class="hlt">tides</span>. The spring-neap cycle and energy of the semidiurnal internal <span class="hlt">tide</span> propagate at the group velocity. Long-range propagation of M2 and S2 internal <span class="hlt">tides</span> in the North Pacific is observed by satellite altimetry. Along a 3,400 km beam spanning 24°-54°N, the M2 and S2 travel times are 10.9 and 11.2 days, respectively. For comparison, it takes the spring-neap cycle 21.1 days to travel over this distance. Spatial maps of the M2 phase velocity, the S2 phase velocity, and the group velocity are determined from phase gradients of the corresponding satellite observed internal <span class="hlt">tide</span> fields. The observed phase and group velocities agree with theoretical values estimated using the World Ocean Atlas 2013 annual-mean ocean stratification.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/17803882','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/17803882"><span>Exacerbation of asthma by Florida "red <span class="hlt">tide</span>" during an ocean sailing trip.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Steensma, David P</p> <p>2007-09-01</p> <p>A 36-year-old man with adult-onset nonallergic triad asthma developed acute bronchospasm and copious sputum production during an offshore sailing excursion on the Gulf Coast of Florida. Symptoms were linked to proximity to blooms of the marine dinoflagellate Karenia brevis (red <span class="hlt">tide</span>) and heavy aerosolized brevetoxin exposure, and symptoms recurred during rechallenge. Patients with respiratory disease who are planning a visit to red <span class="hlt">tide</span>-prone seaside areas should be cautioned to bring their pulmonary medications, and clinicians should be aware that reactive airway symptoms may be triggered by exposure to red <span class="hlt">tide</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=1240666','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=1240666"><span>The potential impacts of climate <span class="hlt">variability</span> and change on health impacts of extreme <span class="hlt">weather</span> events in the United States.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Greenough, G; McGeehin, M; Bernard, S M; Trtanj, J; Riad, J; Engelberg, D</p> <p>2001-01-01</p> <p>Extreme <span class="hlt">weather</span> events such as precipitation extremes and severe storms cause hundreds of deaths and injuries annually in the United States. Climate change may alter the frequency, timing, intensity, and duration of these events. Increases in heavy precipitation have occurred over the past century. Future climate scenarios show likely increases in the frequency of extreme precipitation events, including precipitation during hurricanes, raising the risk of floods. Frequencies of tornadoes and hurricanes cannot reliably be projected. Injury and death are the direct health impacts most often associated with natural disasters. Secondary effects, mediated by changes in ecologic systems and public health infrastructure, also occur. The health impacts of extreme <span class="hlt">weather</span> events hinge on the vulnerabilities and recovery capacities of the natural environment and the local population. Relevant <span class="hlt">variables</span> include building codes, warning systems, disaster policies, evacuation plans, and relief efforts. There are many federal, state, and local government agencies and nongovernmental organizations involved in planning for and responding to natural disasters in the United States. Future research on health impacts of extreme <span class="hlt">weather</span> events should focus on improving climate models to project any trends in regional extreme events and as a result improve public health preparedness and mitigation. Epidemiologic studies of health effects beyond the direct impacts of disaster will provide a more accurate measure of the full health impacts and will assist in planning and resource allocation. PMID:11359686</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li class="active"><span>20</span></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_20 --> <div id="page_21" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li class="active"><span>21</span></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li><a href="#" onclick='return showDiv("page_23");'>23</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="401"> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/11359686','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/11359686"><span>The potential impacts of climate <span class="hlt">variability</span> and change on health impacts of extreme <span class="hlt">weather</span> events in the United States.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Greenough, G; McGeehin, M; Bernard, S M; Trtanj, J; Riad, J; Engelberg, D</p> <p>2001-05-01</p> <p>Extreme <span class="hlt">weather</span> events such as precipitation extremes and severe storms cause hundreds of deaths and injuries annually in the United States. Climate change may alter the frequency, timing, intensity, and duration of these events. Increases in heavy precipitation have occurred over the past century. Future climate scenarios show likely increases in the frequency of extreme precipitation events, including precipitation during hurricanes, raising the risk of floods. Frequencies of tornadoes and hurricanes cannot reliably be projected. Injury and death are the direct health impacts most often associated with natural disasters. Secondary effects, mediated by changes in ecologic systems and public health infrastructure, also occur. The health impacts of extreme <span class="hlt">weather</span> events hinge on the vulnerabilities and recovery capacities of the natural environment and the local population. Relevant <span class="hlt">variables</span> include building codes, warning systems, disaster policies, evacuation plans, and relief efforts. There are many federal, state, and local government agencies and nongovernmental organizations involved in planning for and responding to natural disasters in the United States. Future research on health impacts of extreme <span class="hlt">weather</span> events should focus on improving climate models to project any trends in regional extreme events and as a result improve public health preparedness and mitigation. Epidemiologic studies of health effects beyond the direct impacts of disaster will provide a more accurate measure of the full health impacts and will assist in planning and resource allocation.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.dtic.mil/docs/citations/ADA514184','DTIC-ST'); return false;" href="http://www.dtic.mil/docs/citations/ADA514184"><span>North Adriatic <span class="hlt">Tides</span>: Observations, Variational Data Assimilation Modeling, and Linear <span class="hlt">Tide</span> Dynamics</span></a></p> <p><a target="_blank" href="http://www.dtic.mil/">DTIC Science & Technology</a></p> <p></p> <p>2009-12-01</p> <p>of the North Adriatic ( Lee et al., 2005). In addition to the ADCP measurements of currents through- out the water column, bottom pressure (by ADCP or...of the year with low levels of stratification (Figure 2, Jeffries and Lee , 2007). Actual generation of internal <span class="hlt">tides</span> in the North Adriatic would...Thompson, K.R., Teague, W. J., Jacobs, G.A., Suk, M.-S., Chang, K.-I., Lee , J.-C. and Choi, B.H. (2004): Data assimilation modeling of the barotropic</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/28625616','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/28625616"><span>Modelling explicit <span class="hlt">tides</span> in the Indonesian seas: An important process for surface sea water properties.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Nugroho, Dwiyoga; Koch-Larrouy, Ariane; Gaspar, Philippe; Lyard, Florent; Reffray, Guillaume; Tranchant, Benoit</p> <p>2018-06-01</p> <p>Very intense internal <span class="hlt">tides</span> take place in Indonesian seas. They dissipate and affect the vertical distribution of temperature and currents, which in turn influence the survival rates and transports of most planktonic organisms at the base of the whole marine ecosystem. This study uses the INDESO physical model to characterize the internal <span class="hlt">tides</span> spatio-temporal patterns in the Indonesian Seas. The model reproduced internal <span class="hlt">tide</span> dissipation in agreement with previous fine structure and microstructure observed in-situ in the sites of generation. The model also produced similar water mass transformation as the previous parameterization of Koch-Larrouy et al. (2007), and show good agreement with observations. The resulting cooling at the surface is 0.3°C, with maxima of 0.8°C at the location of internal <span class="hlt">tides</span> energy, with stronger cooling in austral winter. The cycle of spring <span class="hlt">tides</span> and neap <span class="hlt">tides</span> modulates this impact by 0.1°C to 0.3°C. These results suggest that mixing due to internal <span class="hlt">tides</span> might also upwell nutrients at the surface at a frequency similar to the tidal frequencies. Implications for biogeochemical modelling are important. Copyright © 2017 Elsevier Ltd. All rights reserved.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017EGUGA..19.9785B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017EGUGA..19.9785B"><span><span class="hlt">Weather</span> types and strokes in the Augsburg region (Southern Germany)</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Beck, Christoph; Ertl, Michael; Giemsa, Esther; Jacobeit, Jucundus; Naumann, Markus; Seubert, Stefanie</p> <p>2017-04-01</p> <p>Strokes are one of the leading causes of morbidity and mortality worldwide and the main reason for longterm care dependency in Germany. Concerning the economical impact on patients and healthcare systems it is of particular importance to prevent this disease as well as to improve the outcome of the affected persons. Beside the primary well-known risk factors like hypertension, cigarette smoking, physical inactivity and others, also <span class="hlt">weather</span> seems to have pronounced influence on the occurrence and frequency of strokes. Previous studies most often focused on effects of singular meteorological <span class="hlt">variables</span> like ambient air temperature, air pressure or humidity. An advanced approach is to link the entire suite of daily <span class="hlt">weather</span> elements classified to air mass- or <span class="hlt">weather</span> types to cerebrovascular morbidity or mortality. In a joint pilot study bringing together climatologists, environmental scientists and physicians from the University of Augsburg and the clinical centre Augsburg, we analysed relationships between singular meteorological parameters as well as combined <span class="hlt">weather</span> effects (e.g. <span class="hlt">weather</span> types) and strokes in the urban area of Augsburg and the surrounding rural region. A total of 17.501 stroke admissions to Neurological Clinic and Clinical Neurophysiology at Klinikum Augsburg between 2006 and 2015 are classified to either "ischaemic" (16.354) or "haemorrhagic" (1.147) subtype according to etiology (based on the International Classification of Diseases - 10th Revision). Spearman correlations between daily frequencies of ischaemic and haemorrhagic strokes and singular atmospheric parameters (T, Tmin, Tmax, air pressure, humidity etc.) measured at the DWD (German <span class="hlt">weather</span> service) meteorological station at Augsburg Muehlhausen are rather low. However, higher correlations are achieved when considering sub-samples of "homogenous <span class="hlt">weather</span> conditions" derived from synoptic circulation classifications: e.g. within almost all of 10 types arising from a classification of</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3792175','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3792175"><span>Between <span class="hlt">tide</span> and wave marks: a unifying model of physical zonation on littoral shores</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Bird, Christopher E.; Franklin, Erik C.; Smith, Celia M.</p> <p>2013-01-01</p> <p>The effects of <span class="hlt">tides</span> on littoral marine habitats are so ubiquitous that shorelines are commonly described as ‘intertidal’, whereas waves are considered a secondary factor that simply modifies the intertidal habitat. However mean significant wave height exceeds tidal range at many locations worldwide. Here we construct a simple sinusoidal model of coastal water level based on both tidal range and wave height. From the patterns of emergence and submergence predicted by the model, we derive four vertical shoreline benchmarks which bracket up to three novel, spatially distinct, and physically defined zones. The (1) emergent tidal zone is characterized by tidally driven emergence in air; the (2) wave zone is characterized by constant (not periodic) wave wash; and the (3) submergent tidal zone is characterized by tidally driven submergence. The decoupling of tidally driven emergence and submergence made possible by wave action is a critical prediction of the model. On wave-dominated shores (wave height ≫ tidal range), all three zones are predicted to exist separately, but on <span class="hlt">tide</span>-dominated shores (tidal range ≫ wave height) the wave zone is absent and the emergent and submergent tidal zones overlap substantially, forming the traditional “intertidal zone”. We conclude by incorporating time and space in the model to illustrate <span class="hlt">variability</span> in the physical conditions and zonation on littoral shores. The wave:<span class="hlt">tide</span> physical zonation model is a unifying framework that can facilitate our understanding of physical conditions on littoral shores whether tropical or temperate, marine or lentic. PMID:24109544</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018MNRAS.tmp.1482G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018MNRAS.tmp.1482G"><span>Numerical Modelling of Tertiary <span class="hlt">Tides</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Gao, Yan; Correia, Alexandre C. M.; Eggleton, Peter P.; Han, Zhanwen</p> <p>2018-06-01</p> <p>Stellar systems consisting of multiple stars tend to undergo tidal interactions when the separations between the stars are short. While tidal phenomena have been extensively studied, a certain tidal effect exclusive to hierarchical triples (triples in which one component star has a much wider orbit than the others) has hardly received any attention, mainly due to its complexity and consequent resistance to being modelled. This tidal effect is the tidal perturbation of the tertiary by the inner binary, which in turn depletes orbital energy from the inner binary, causing the inner binary separation to shrink. In this paper, we develop a fully numerical simulation of these "tertiary <span class="hlt">tides</span>" by modifying established tidal models. We also provide general insight as to how close a hierarchical triple needs to be in order for such an effect to take place, and demonstrate that our simulations can effectively retrieve the orbital evolution for such systems. We conclude that tertiary <span class="hlt">tides</span> are a significant factor in the evolution of close hierarchical triples, and strongly influence at least ˜1% of all multiple star systems.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.er.usgs.gov/publication/70017991','USGSPUBS'); return false;" href="https://pubs.er.usgs.gov/publication/70017991"><span>Modeling the <span class="hlt">tides</span> of Massachusetts and Cape Cod Bays</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Jenter, H.L.; Signell, R.P.; Blumberg, A.F.; ,</p> <p>1993-01-01</p> <p>A time-dependent, three-dimensional numerical modeling study of the <span class="hlt">tides</span> of Massachusetts and Cape Code Bays, motivated by construction of a new sewage treatment plant and ocean outfall for the city of Boston, has been undertaken by the authors. The numerical model being used is a hybrid version of the Blumberg and Mellor ECOM3D model, modified to include a semi-implicit time-stepping scheme and transport of a non-reactive dissolved constituent. <span class="hlt">Tides</span> in the bays are dominated by the semi-diurnal frequencies, in particular by the M2 <span class="hlt">tide</span>, due to the resonance of these frequencies in the Gulf of Maine. The numerical model reproduces, well, measured tidal ellipses in unstratified wintertime conditions. Stratified conditions present more of a problem because tidal-frequency internal wave generation and propagation significantly complicates the structure of the resulting tidal field. Nonetheless, the numerical model reproduces qualitative aspects of the stratified tidal flow that are consistent with observations in the bays.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/biblio/6563598-influence-fortnightly-earth-tides-kilauea-volcano-hawaii','SCIGOV-STC'); return false;" href="https://www.osti.gov/biblio/6563598-influence-fortnightly-earth-tides-kilauea-volcano-hawaii"><span>Influence of fortnightly earth <span class="hlt">tides</span> at Kilauea Volcano, Hawaii</span></a></p> <p><a target="_blank" href="http://www.osti.gov/search">DOE Office of Scientific and Technical Information (OSTI.GOV)</a></p> <p>Dzurisin, D.</p> <p>1980-11-01</p> <p>Analysis of 52 historic eruptions confirms the premise that fortnightly earth <span class="hlt">tides</span> play a significant role in triggering activity at Kilauea Volcano, Hawaii. Since January 1832, nearly twice as many eruptions have occurred nearer fortnightly tidal maximum than tidal minimum (34 vs 18). A straightforward significance test indicates that the likelihood of a fortnightly tidal influence on Kilauea eruptions is roughly 90%. This is not the case for Mauna Loa Volcano, where 37 historic eruptions have been distributed randomly with respect to the fortnightly <span class="hlt">tide</span>. At Kilauea, stresses induced by fortnightly earth <span class="hlt">tides</span> presumably act in concert with volcanic andmore » tectonic stresses to trigger shallow magma movements along preexisting zones of weakness. Differences in structure or internal plumbing may limit the effectiveness of this mechanism at Mauna Loa. Tidal effects seem to be less marked at shields than at some island-arc volcanoes, possibly because higher average volcanic stress rates in Hawaii more often override the effects of tidal stresses.« less</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.er.usgs.gov/publication/70012341','USGSPUBS'); return false;" href="https://pubs.er.usgs.gov/publication/70012341"><span>Influence of fortnightly earth <span class="hlt">tides</span> at Kilauea Volcano, Hawaii.</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Dzurisin, D.</p> <p>1980-01-01</p> <p>Analysis of 52 historic eruptions confirms the premise that fortnightly earth <span class="hlt">tides</span> play a significant role in triggering activity at Kilauea Volcano, Hawaii. Since January 1832, nearly twice as many eruptions have occurred nearer fortnightly tidal maximum than tidal minimum (34 vs. 18). A straightforward significance test indicates that the likelihood of a fortnightly tidal influence on Kilauea eruptions is roughly 90%. This is not the case for Mauna Loa Volcano, where 37 historic eruptions have been distributed randomly with respect to the fortnightly <span class="hlt">tide</span>. At Kilauea, stresses induced by fortnightly earth <span class="hlt">tides</span> presumably act in concert with volcanic and tectonic stresses to trigger shallow magma movements along preexisting zones of weakness. Differences in structure or internal plumbing may limit the effectiveness of this mechanism at Mauna Loa. Tidal effects seem to be less marked at shields than at some island-arc volcanoes, possibly because higher average volcanic stress rates in Hawaii more often override the effects of tidal stresses.-Author</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19990088419&hterms=Reddy&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D90%26Ntt%3DReddy','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19990088419&hterms=Reddy&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D90%26Ntt%3DReddy"><span>The Role of Gravity Waves in Generating Equatorial Oscillations in Modulating Atmospheric <span class="hlt">Tides</span></span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Mayr, H. G.; Mengel, J. G.; Chan, K. L.; Porter, H. S.; Reddy, C. A.</p> <p>1999-01-01</p> <p>We discuss a Numerical Spectral Mode (NSM) that extends from the ground up into the thermosphere and incorporates Hines' Doppler spread parameterization (DSP) for small scale gravity waves (GW). This model is applied to describe the seasonal variations in the mean zonal circulation, the semi-annual and quasi-biennial oscillations (SAO and QBO), as well as the <span class="hlt">tides</span> and planetary waves in the middle atmosphere. Initial results showed that this model can reproduce the salient features observed, including the QBO extending into the upper mesosphere inferred from UARS measurements. The model has now been extended to simulate also: (a) the zonal circulation of the lower stratosphere and upper troposphere, and (b) the upwelling at equatorial latitudes associated with the Brewer Dobsen circulation that affects the dynamics significantly as pointed out by Dunkerton. Upward vertical winds increase the period of the QBO observed from the ground. To compensate for that, one needs to increase in the model the eddy diffusivity and the GW momentum flux, bringing the latter closer to values recommended in the DSP. This development is conducive to extending the QBO and SAO to higher latitudes through global scale momentum redistribution. Multi-year interannual oscillations are generated through wave filtering by the solar driven annual oscillation in the zonal circulation. In a 3D version of the model, wave momentum is absorbed and dissipated by <span class="hlt">tides</span> and planetary waves. A somewhat larger GW source (well within the DSP range) is then required to generate realistic QBO and SAO amplitudes. Since GW momentum is deposited in the altitude regime of increasing winds, the amplitude of the diurnal <span class="hlt">tide</span> is amplified and its vertical wavelength is reduced at altitudes between 70 and 120 km. Wave filtering by the mean zonal circulation causes the GW flux to peak during equinox, and this produces a large semi-annual variation in the <span class="hlt">tide</span> that has been observed on UARS. Without the diurnal</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017AGUFMEP13D..02H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017AGUFMEP13D..02H"><span><span class="hlt">Tides</span> Stabilize Deltas until Humans Interfere</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Hoitink, T.; Zheng Bing, W.; Vermeulen, B.; Huismans, Y.; Kastner, K.</p> <p>2017-12-01</p> <p>Despite global concerns about river delta degradation caused by extraction of natural resources, sediment retention by reservoirs and sea-level rise, human activity in the world's largest deltas intensifies. In this review, we argue that <span class="hlt">tides</span> tend to stabilize deltas until humans interfere. Under natural circumstances, delta channels subject to <span class="hlt">tides</span> are more stable than their fluvial-dominated counterparts. The oscillatory tidal flow counteracts the processes responsible for bank erosion, which explains why unprotected tidal channels migrate only slowly. Peak river discharges attenuate the <span class="hlt">tides</span>, which creates storage space to accommodate the extra river discharge during extreme events and as a consequence, reduce flood risk. With stronger <span class="hlt">tides</span>, the river discharge is being distributed more evenly over the various branches in a delta, preventing silting up of smaller channels. Human interference in deltas is massive. Storm surge barriers are constructed, new land is being reclaimed and large-scale sand excavation takes place, to collect building material. Evidence from deltas around the globe shows that in human-controlled deltas the tidal motion often plays a destabilizing role. In channels of the Rhine-Meuse Delta, some 100 scour holes are identified, which relates to the altered tidal motion after completion of a storm surge barrier. Sand mining has led to widespread river bank failures in the tidally-influenced Mekong Delta. The catastrophic flood event in the Gauges-Brahmaputra Delta by Cyclone Aila, which caused the inundation of an embanked polder area for over two years, was preceded by river bank erosion at the mouths of formal tidal channels that were blocked by the embankment. Efforts to predict the developments of degrading deltas are few. Existing delta models are capable of reproducing expanding deltas, which is essentially a matter of simulating the transport of sediment from source in a catchment to the sink in a delta. Processes of soil</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3031498','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3031498"><span>Temporal Associations between <span class="hlt">Weather</span> and Headache: Analysis by Empirical Mode Decomposition</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Yang, Albert C.; Fuh, Jong-Ling; Huang, Norden E.; Shia, Ben-Chang; Peng, Chung-Kang; Wang, Shuu-Jiun</p> <p>2011-01-01</p> <p>Background Patients frequently report that <span class="hlt">weather</span> changes trigger headache or worsen existing headache symptoms. Recently, the method of empirical mode decomposition (EMD) has been used to delineate temporal relationships in certain diseases, and we applied this technique to identify intrinsic <span class="hlt">weather</span> components associated with headache incidence data derived from a large-scale epidemiological survey of headache in the Greater Taipei area. Methodology/Principal Findings The study sample consisted of 52 randomly selected headache patients. The <span class="hlt">weather</span> time-series parameters were detrended by the EMD method into a set of embedded oscillatory components, i.e. intrinsic mode functions (IMFs). Multiple linear regression models with forward stepwise methods were used to analyze the temporal associations between <span class="hlt">weather</span> and headaches. We found no associations between the raw time series of <span class="hlt">weather</span> <span class="hlt">variables</span> and headache incidence. For decomposed intrinsic <span class="hlt">weather</span> IMFs, temperature, sunshine duration, humidity, pressure, and maximal wind speed were associated with headache incidence during the cold period, whereas only maximal wind speed was associated during the warm period. In analyses examining all significant <span class="hlt">weather</span> <span class="hlt">variables</span>, IMFs derived from temperature and sunshine duration data accounted for up to 33.3% of the variance in headache incidence during the cold period. The association of headache incidence and <span class="hlt">weather</span> IMFs in the cold period coincided with the cold fronts. Conclusions/Significance Using EMD analysis, we found a significant association between headache and intrinsic <span class="hlt">weather</span> components, which was not detected by direct comparisons of raw <span class="hlt">weather</span> data. Contributing <span class="hlt">weather</span> parameters may vary in different geographic regions and different seasons. PMID:21297940</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.er.usgs.gov/publication/70195431','USGSPUBS'); return false;" href="https://pubs.er.usgs.gov/publication/70195431"><span>Consortial brown <span class="hlt">tide</span> − picocyanobacteria blooms in Guantánamo Bay, Cuba</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Hall, Nathan S; Litaker, R. Wayne; Kenworthy, W. Judson; Vandersea, Mark W.; Sunda, William G.; Reid, James P.; Slone, Daniel H.; Butler, Susan M.</p> <p>2018-01-01</p> <p>A brown <span class="hlt">tide</span> bloom of Aureoumbra lagunensis developed in Guantánamo Bay, Cuba during a period of drought in 2013 that followed heavy winds and rainfall from Hurricane Sandy in late October 2012. Based on satellite images and water turbidity measurements, the bloom appeared to initiate in January 2013. The causative species (A. lagunensis) was confirmed by microscopic observation, and pigment and genetic analyses of bloom samples collected on May 28 of that year. During that time, A. lagunensis reached concentrations of 900,000 cells ml−1 (28 ppm by biovolume) in the middle portion of the Bay. Samples could not be collected from the northern (Cuban) half of the Bay because of political considerations. Subsequent sampling of the southern half of the Bay in November 2013, April 2014, and October 2014 showed persistent lower concentrations of A. lagunensis, with dominance shifting to the cyanobacterium Synechococcus (up to 33 ppm in April), an algal group that comprised a minor bloom component on May 28. Thus, unlike the brown <span class="hlt">tide</span> bloom in Laguna Madre, which lasted 8 years, the bloom in Guantánamo Bay was short-lived, much like recent blooms in the Indian River, Florida. Although hypersaline conditions have been linked to brown <span class="hlt">tide</span> development in the lagoons of Texas and Florida, observed euhaline conditions in Guantánamo Bay (salinity 35–36) indicate that strong hypersalinity is not a requirement for A. lagunensis bloom formation. Microzooplankton biomass dominated by ciliates was high during the observed peak of the brown <span class="hlt">tide</span>, and ciliate abundance was high compared to other systems not impacted by brown <span class="hlt">tide</span>. Preferential grazing by zooplankton on non-brown <span class="hlt">tide</span> species, as shown in A. lagunensis blooms in Texas and Florida, may have been a factor in the development of the Cuban brown <span class="hlt">tide</span> bloom. However, subsequent selection of microzooplankton capable of utilizing A. lagunensis as a primary food source may have contributed to the</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2010AGUFM.G51C0680K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2010AGUFM.G51C0680K"><span>Arctic Ocean <span class="hlt">Tides</span> from GRACE Satellite Accelerations</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Killett, B.; Wahr, J. M.; Desai, S. D.; Yuan, D.; Watkins, M. M.</p> <p>2010-12-01</p> <p>Because missions such as TOPEX/POSEIDON don't extend to high latitudes, Arctic ocean tidal solutions aren't constrained by altimetry data. The resulting errors in tidal models alias into monthly GRACE gravity field solutions at all latitudes. Fortunately, GRACE inter-satellite ranging data can be used to solve for these <span class="hlt">tides</span> directly. Seven years of GRACE inter-satellite acceleration data are inverted using a mascon approach to solve for residual amplitudes and phases of major solar and lunar <span class="hlt">tides</span> in the Arctic ocean relative to FES 2004. Simulations are performed to test the inversion algorithm's performance, and uncertainty estimates are derived from the tidal signal over land. Truncation error magnitudes and patterns are compared to the residual tidal signals.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2006IJBm...50..275S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2006IJBm...50..275S"><span>Plant development scores from fixed-date photographs: the influence of <span class="hlt">weather</span> <span class="hlt">variables</span> and recorder experience</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Sparks, T. H.; Huber, K.; Croxton, P. J.</p> <p>2006-05-01</p> <p>In 1944, John Willis produced a summary of his meticulous record keeping of <span class="hlt">weather</span> and plants over the 30 years 1913 1942. This publication contains fixed-date, fixed-subject photography taken on the 1st of each month from January to May, using as subjects snowdrop Galanthus nivalis, daffodil Narcissus pseudo-narcissus, horse chestnut Aesculus hippocastanum and beech Fagus sylvatica. We asked 38 colleagues to assess rapidly the plant development in each of these photographs according to a supplied five-point score. The mean scores from this exercise were assessed in relation to mean monthly <span class="hlt">weather</span> <span class="hlt">variables</span> preceding the date of the photograph and the consistency of scoring was examined according to the experience of the recorders. Plant development was more strongly correlated with mean temperature than with minimum or maximum temperatures or sunshine. No significant correlations with rainfall were detected. Whilst mean scores were very similar, botanists were more consistent in their scoring of developmental stages than non-botanists. However, there was no overall pattern for senior staff to be more consistent in scoring than junior staff. These results suggest that scoring of plant development stages on fixed dates could be a viable method of assessing the progress of the season. We discuss whether such recording could be more efficient than traditional phenology, especially in those sites that are not visited regularly and hence are less amenable to frequent or continuous observation to assess when a plant reaches a particular growth stage.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014ECSS..149..120P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014ECSS..149..120P"><span>Recruitment of fish larvae and juveniles into two estuarine nursery areas with evidence of ebb <span class="hlt">tide</span> use</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Pattrick, Paula; Strydom, Nadine</p> <p>2014-08-01</p> <p>Recruitment of larvae and early juveniles, against the ebb <span class="hlt">tide</span> in the shallower, slower-flowing marginal areas of two permanently open estuaries in the Eastern Cape, South Africa was observed. To determine tidal, diel and seasonal variations of larval and juvenile fish recruitment, fyke nets were used during a 24-hour cycle over two years from December 2010 to October 2012. On either side of each estuary bank, two fyke nets with mouth openings facing opposite directions (i.e. one net facing the incoming or outgoing <span class="hlt">tide</span> and the other facing the opposing direction) were used to sample fishes. The aims of this study were to determine if 1) on the flood <span class="hlt">tide</span>, were the nets facing the incoming <span class="hlt">tide</span> collecting more larvae and early juveniles recruiting into the estuarine nursery area, than the nets facing the opposing direction and 2) on the ebb <span class="hlt">tide</span>, were the nets facing the sea, and hence the opposing direction of the outgoing ebb <span class="hlt">tide</span>, collecting more fishes recruiting into the nursery against the ebb <span class="hlt">tide</span>, than the nets facing the outgoing ebb <span class="hlt">tide</span>? Larval and juvenile fish CPUE, species diversity and richness varied seasonally between estuarine systems and between diel and tidal conditions. Highest catches were recorded on the flood <span class="hlt">tide</span>, which coincided with sunrise in the Swartkops Estuary. Greatest catches of larvae and early juveniles were observed during the ebb <span class="hlt">tide</span> at night in the Sundays Estuary. On the ebb <span class="hlt">tide</span>, higher catches of several dominant species and several commercially important fishery species, occurred in the fyke nets which faced the sea, indicating the early developmental stages of these fish species are not necessarily being lost from the nursery. These larvae and juveniles are actively swimming against the ebb <span class="hlt">tide</span> in the shallower, slower-flowing marginal areas facilitating recruitment against ebb flow.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017MS%26E..245d2024M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017MS%26E..245d2024M"><span>Predicting Average Vehicle Speed in Two Lane Highways Considering <span class="hlt">Weather</span> Condition and Traffic Characteristics</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Mirbaha, Babak; Saffarzadeh, Mahmoud; AmirHossein Beheshty, Seyed; Aniran, MirMoosa; Yazdani, Mirbahador; Shirini, Bahram</p> <p>2017-10-01</p> <p>Analysis of vehicle speed with different <span class="hlt">weather</span> condition and traffic characteristics is very effective in traffic planning. Since the <span class="hlt">weather</span> condition and traffic characteristics vary every day, the prediction of average speed can be useful in traffic management plans. In this study, traffic and <span class="hlt">weather</span> data for a two-lane highway located in Northwest of Iran were selected for analysis. After merging traffic and <span class="hlt">weather</span> data, the linear regression model was calibrated for speed prediction using STATA12.1 Statistical and Data Analysis software. <span class="hlt">Variables</span> like vehicle flow, percentage of heavy vehicles, vehicle flow in opposing lane, percentage of heavy vehicles in opposing lane, rainfall (mm), snowfall and maximum daily wind speed more than 13m/s were found to be significant <span class="hlt">variables</span> in the model. Results showed that <span class="hlt">variables</span> of vehicle flow and heavy vehicle percent acquired the positive coefficient that shows, by increasing these <span class="hlt">variables</span> the average vehicle speed in every <span class="hlt">weather</span> condition will also increase. Vehicle flow in opposing lane, percentage of heavy vehicle in opposing lane, rainfall amount (mm), snowfall and maximum daily wind speed more than 13m/s acquired the negative coefficient that shows by increasing these <span class="hlt">variables</span>, the average vehicle speed will decrease.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017AGUFM.S41C0785M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017AGUFM.S41C0785M"><span>Numerical study of the effect of earth <span class="hlt">tides</span> on recurring short-term slow slip events</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Matsuzawa, T.; Tanaka, Y.; Shibazaki, B.</p> <p>2017-12-01</p> <p>Short-term slow slip events (SSEs) in the Nankai region are affected by earth <span class="hlt">tides</span> (e.g., Nakata et al., 2008; Ide and Tanaka, 2014; Yabe et al., 2015). The effect of tidal stress on the SSEs is also examined numerically (e.g., Hawthorne and Rubin, 2013). In our previous study (Matsuzawa et al., 2017, JpGU-AGU), we numerically simulated SSEs in the Shikoku region, and reported that tidal stress makes the variance of recurrence intervals of SSEs smaller in relatively isolated SSE regions. However, the reason of such stable recurrence was not clear. In this study, we examine the tidal effect on short-term SSEs based on a flat plate and a realistic plate model (e.g., Matsuzawa et al., 2013, GRL). We adopt a rate- and state-dependent friction law (RS-law) with cutoff velocities as in our previous studies (Matsuzawa et al., 2013). We assume that (a-b) value in the RS-law is negative within the short-term SSE region, and positive outside the region. In a flat plate model, the short-term SSE region is a circular patch with the radius of 6 km. In a realistic plate model, the short-term SSE region is based on the actual distribution of low-frequency tremor. Low effective normal stress is assumed at the depth of SSEs. Calculating stress change by earth <span class="hlt">tides</span> as in Yabe et al., (2015), we examine the stress perturbation by two different earth <span class="hlt">tides</span> with the period of semidiurnal (M2) and fortnight (Mf) <span class="hlt">tide</span> in this study. In the result of a flat plate case, amplitude of SSEs becomes smaller just after the slip at whole simulated area. Recurring SSEs become clear again within one year in the case with <span class="hlt">tides</span> (M2 or Mf), while the recurrence becomes clear after seven years in the case without <span class="hlt">tides</span>. Interestingly, the effect of the Mf <span class="hlt">tide</span> is similar to the case with the M2 <span class="hlt">tide</span>, even though the amplitude of the Mf <span class="hlt">tide</span> (0.01 kPa) is two-order smaller than that of the M2 <span class="hlt">tide</span>. In the realistic plate model of Shikoku, clear recurrence of short-term SSEs is found earlier than the</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016OSJ....51..195H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016OSJ....51..195H"><span>Tidal asymmetry in a tidal creek with mixed mainly semidiurnal <span class="hlt">tide</span>, Bushehr Port, Persian Gulf</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Hosseini, Seyed Taleb; Chegini, Vahid; Sadrinasab, Masoud; Siadatmousavi, Seyed Mostafa; Yari, Sadegh</p> <p>2016-03-01</p> <p>This study investigated the tidal asymmetry imposed by both the interaction of principal <span class="hlt">tides</span> and the higher harmonics generated by distortions within a tidal creek network with mixed mainly semidiurnal <span class="hlt">tide</span> in the Bushehr Port, Persian Gulf. Since velocity and water-level imposed by principal triad <span class="hlt">tides</span> K1-O1-M2 are in quadrature, duration asymmetries during a tidal period in this short, shallow inverse estuary should be manifest as skewed velocities. The principal <span class="hlt">tides</span> produce periodic asymmetries including a strong ebb-dominance and a weak flood-dominance condition during spring and neap <span class="hlt">tides</span> respectively. The higher harmonics induced by nonlinearities engender a flood-dominance condition where the convergence effects are higher than frictional effects, and an ebbdominance condition where intertidal storage are extended. Since the triad K1-O1-M2 driven asymmetry is not overcome by higher harmonics close to the mouth, the periodic asymmetry dominates within the creek in which higher harmonics reinforce the weak flood-dominance (strong ebb-dominance) condition in the convergent channel (divergent area). Also, the maximum flood and the maximum ebb from all harmonic constituents occurred close to high water slack time during both spring and neap <span class="hlt">tides</span> in this short creek. Since occational wetting of intertidal areas happened close to the high water (HW) time during spring <span class="hlt">tide</span>, the water level flooded slowly close to the HW time of the spring <span class="hlt">tide</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/22742792','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/22742792"><span>Comparative study of airborne Alternaria conidia levels in two cities in Castilla-La Mancha (central Spain), and correlations with <span class="hlt">weather</span>-related <span class="hlt">variables</span>.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Sabariego, Silvia; Bouso, Veronica; Pérez-Badia, Rosa</p> <p>2012-01-01</p> <p>Alternaria conidia are among the airborne biological particles known to trigger allergic respiratory diseases. The presented paper reports on a study of seasonal variations in airborne Alternaria conidia concentrations in 2 cities in the central Spanish region of Castilla-La Mancha, Albacete and Toledo. The influence of <span class="hlt">weather</span>-related <span class="hlt">variables</span> on airborne conidia levels and distribution was also analysed. Sampling was carried out from 2008-2010 using a Hirst sampler, following the methodology established by the Spanish Aerobiology Network. Annual airborne Alternaria conidia counts were higher in Toledo (annual mean 3,936 conidia) than in Albacete (annual mean 2,268 conidia). Conidia were detected in the air throughout the year, but levels peaked between May-September. Considerable year-on-year variations were recorded both in total annual counts and in seasonal distribution. A significant positive correlation was generally found between mean daily Alternaria counts and both temperature and hours of sunlight, while a significant negative correlation was recorded for relative humidity, daily and cumulative rainfall, and wind speed. Regression models indicated that between 31%-52% of the variation in airborne Alternaria conidia concentrations could be explained by <span class="hlt">weather</span>-related <span class="hlt">variables</span>.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li class="active"><span>21</span></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li><a href="#" onclick='return showDiv("page_23");'>23</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_21 --> <div id="page_22" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li class="active"><span>22</span></li> <li><a href="#" onclick='return showDiv("page_23");'>23</a></li> <li><a href="#" onclick='return showDiv("page_24");'>24</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="421"> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/12867197','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/12867197"><span>HPLC pigment analysis of marine phytoplankton during a red <span class="hlt">tide</span> occurrence in Tolo Harbour, Hong Kong.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Wong, C Kwan; Wong, C Kim</p> <p>2003-09-01</p> <p>A red <span class="hlt">tide</span> was detected in the inner parts of Tolo Harbour, Hong Kong, in November 2000. Water samples were collected from a fixed station at the centre of the red <span class="hlt">tide</span> patch for microscopic analysis of phytoplankton community composition and high performance liquid chromatography (HPLC) analysis of phytoplankton pigments. At the peak of the red <span class="hlt">tide</span> on 24 November 2000, phytoplankton was dominated by the dinoflagellate Scrippsiella trochoidea. The red <span class="hlt">tide</span> began to decline at the end of November and, by 1 December 2000, the phytoplankton was dominated by diatoms. Chlorophylls and carotenoids in water samples were analysed using HPLC pigment separation technique. Dinoflagellates were indicated by the signature pigment peridinin. Significant correlation (r=0.999) was found between the peridinin concentration and dinoflagellate density. A decrease in peridinin and an increase in fucoxanthin, a major carotenoid in diatoms, marked the shift in phytoplankton composition at the end of the red <span class="hlt">tide</span>. HPLC analysis also revealed the occurrence of minor phytoplankton groups that are difficult to identify by light microscopy. Red <span class="hlt">tide</span> monitoring and study of red <span class="hlt">tide</span> dynamics in Hong Kong have been based on cell counting and spectrophotometric or fluorometric measurement of chlorophyll a. HPLC pigment analysis provides an effective alternative for investigating phytoplankton dynamics during red <span class="hlt">tide</span> and other algal blooms.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013PhDT.......126G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013PhDT.......126G"><span>Hydrodynamical simulations of strong <span class="hlt">tides</span> in astrophysical systems</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Guillochon, James</p> <p>2013-07-01</p> <p>At the simplest level, gravitational sources are considered to be point-like and in solitude, with a radial force that falls off as r -2. In reality, all astrophysical objects aside from black holes are extended in space, and can be deformed by the tidal forces arising from the proximity of companion objects with large average densities. When these forces are weak, the response of an object to a <span class="hlt">tide</span> can be through a decomposition into basis functions, but this approach fails when the <span class="hlt">tide</span> is strong enough to deform an object by a distance equal to its own size. Under these circumstances, a hydrodynamical representation of the object is required to understand the true tidal response. In this thesis, we present a number of examples of physical systems in which <span class="hlt">tides</span> dominate the dynamics. First, we consider the case of a star that encounters a supermassive black hole (SMBH) in a deeply penetrating encounter, resulting in a dramatic compression that produces shocks that would be observable in the X-ray. Second, we present the results of hydrodynamical simulations that demonstrate a new mechanism for igniting Type Ia supernovae from binary systems composed of two white dwarfs undergoing Roche-lobe overflow. Third, we investigate the survival prospects of giant planets that have been scattered into highly eccentricity orbits and are exposed to a strong <span class="hlt">tide</span> applied by their parent star. Fourth, we systematically map the fallback rate resulting from the tidal disruptions of stars by SMBHs. Finally, we use what we have learned about the feeding rate to model determine the highest-likelihood model for an observed prototypical tidal disruption event.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/29730413','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/29730413"><span>Relationship between phytoplankton community succession and environmental parameters in Qinhuangdao coastal areas, China: A region with recurrent brown <span class="hlt">tide</span> outbreaks.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Cui, Lei; Lu, Xinxin; Dong, Yuelei; Cen, Jingyi; Cao, Rongbo; Pan, Lin; Lu, Songhui; Ou, Linjian</p> <p>2018-05-03</p> <p>The picoplanktonic pelagophyte Aureococcus anophagefferens could trigger harmful algal blooms (HABs) to discolor water in brown, known as brown <span class="hlt">tide</span>. Since 2009, large-scale brown <span class="hlt">tides</span>, caused by A. anophagefferens, had been occurred in early summer for three consecutive years in the coastal waters of Qinhuangdao, China and resulted considerable deleterious effects on the scallop mariculture industry. The causes for the occurrence of brown <span class="hlt">tides</span> were not fully understood. Therefore, we conducted a one-year survey from June 2013 to May 2014 to study the seasonal succession of the phytoplankton community, including A. anophagefferens and its relationship with environmental <span class="hlt">variables</span> in the area. The results revealed that the population dynamics of the phytoplankton community were significant variation with seasonal succession, in which A. anophagefferens played an important role during the entire year. The trend of the whole diversity index indicated that the community structure became more stable in winter. The results of principle component analysis (PCA) applied to the environmental factors indicated four major seasonal groups in the environmental <span class="hlt">variables</span>. The water temperature, silicate and total nitrogen were contributed to the environment in summer, autumn and spring, respectively. In addition, a few another environmental factors commonly contributed to the winter waterbody, indicated that the aquatic environment is more complex in the cold season. The result revealed that the phytoplankton community structure and its variation were mainly affected by the hydrological factors, by using the redundancy analysis (RDA) for the relationship between dominant species and the environment. Furthermore, we inferred Chaetoceros decipiens as a potential species for the breakout of harmful algae blooms (HABs) by RDA ordination. We concluded that the key factor for the seasonal variations in the dynamics of phytoplankton community could be the hydrological parameters in</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.usgs.gov/wri/1984/4293/report.pdf','USGSPUBS'); return false;" href="https://pubs.usgs.gov/wri/1984/4293/report.pdf"><span>Water-surface elevations for the high <span class="hlt">tide</span> of December 15, 1977, in the Puget Sound region, Washington</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Nelson, L.M.</p> <p>1985-01-01</p> <p>An unusually high oceanic <span class="hlt">tide</span> on December 15, 1977, caused flooding of lowlying, nearshore parts of western Washington, including several areas in the Puget Sound region. At Seattle, the December 15 high <span class="hlt">tide</span> of 14.8 feet above MLLW (mean lower low water datum; 8.55 feet above the National Geodetic Vertical Daltum of 1929, or NGVD) was 0.1 foot higher than the 100-year high <span class="hlt">tide</span>. At Neah Bay, near the western end of the Straits of Juan de Fuca, however, the high <span class="hlt">tide</span> of 8.77 feet MLLW (4.55 feet NGVD) on that date was 3.2 feet lower than the 100-year high <span class="hlt">tide</span>. This study has identified the observed December 15 high-<span class="hlt">tide</span> elevations at many locations in the Puget Sound region. The observed high <span class="hlt">tide</span> then was much higher than predicted in most of the Puget Sound region, primarily as the result of a very low barametric pressure. Little damage from wind waves was reported. Elevation profiles for the predicted and observed high <span class="hlt">tides</span> on December 15 and for several other selected <span class="hlt">tide</span> levels indicate an increase in the maximum height in the inland direction, except near Port Angeles, and show abrupt changes in tidal elevations at three constrictions - Admiralty Inlet, Tacoma Narrows, and Deception Pass. (USGS)</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2003JGRC..108.3151F','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2003JGRC..108.3151F"><span>Internal <span class="hlt">tides</span> in the Northern Gulf of California</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Filonov, Anatoliy E.; LavíN, M. F.</p> <p>2003-05-01</p> <p>The characteristics of the internal <span class="hlt">tide</span> in the Northern Gulf of California are described using data from two moored arrays of temperature and current sensors, one for summer and one for winter, located between Angel de la Guarda Island and the mainland. From the summer six-sensor mooring it was found that: (1) the current fluctuations are dominated by the semidiurnal frequency band, while the quarterdiurnal frequency dominated the temperature fluctuations. (2) The baroclinic semidiurnal horizontal current fluctuations are aligned with the gulf axis, and have amplitudes of 10-15 cm s-1; the vertical displacements reached 4 m in this frequency band. (3) The vertical modal structure for the temperature and velocity oscillations was dominated by the first and third modes. (4) The energy of the semidiurnal internal <span class="hlt">tide</span> is 45% of that of the barotropic <span class="hlt">tide</span>. (5) Vertical wave number spectra showed slightly asymmetric peaks in the high wave number components, indicating that their downflowing energy is larger than that flowing upward. From the winter two-sensor mooring, it was found that the vertical oscillations were mainly semidiurnal, with root mean square amplitudes of 7 m.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://eric.ed.gov/?q=salinity&pg=2&id=ED128205','ERIC'); return false;" href="https://eric.ed.gov/?q=salinity&pg=2&id=ED128205"><span>Investigations in Marine Chemistry: <span class="hlt">Tide</span> Pool Ecology.</span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Schlenker, Richard M.</p> <p></p> <p>Students investigated the salinity of <span class="hlt">tide</span> pools at different levels in the intertidal zone. Data are analyzed collectively. Students graphed and discussed data. Included are suggestions for evaluation and further study. (Author)</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016EGUGA..1810963L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016EGUGA..1810963L"><span>High-resolution barotropic <span class="hlt">tide</span> modelling in the South China Sea</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Luu, Quang-Hung; Tkalich, Pavel</p> <p>2016-04-01</p> <p>The South China Sea (SCS) links two of the largest open oceans, the Pacific and the Indian, mainly through the Luzon-Taiwan Straits in the northeast and the Malacca-Karimata Straits in the southwest, respectively. It has a rhino-like shape of 3000-km long, whose belly is contiguous to Vietnam and back leans on the Philippines. The highly irregular topography includes the Gulf of Tonkin in the north, the Gulf Thailand in the southwest, and several small islands in the middle of SCS (i.e., the Spratly and the Paracels) resulting in complicated astronomic <span class="hlt">tides</span> and tidal dynamics in this region. In this study, we present high-resolution simulation of <span class="hlt">tides</span> in the SCS using the Semi-Implicit Eulerian-Lagrangian Finite-Element (SELFE) model. We derive the bathymetry from the Shuttle Radar Topography Mission (SMRT) 15-arc second dataset, one of the finest global topography data sources. Our particular interest is to resolve small bathymetry features and islands in the middle of the SCS which we obtained by digitizing very-high resolution satellite images (30-m accuracy). An unstructured triangular mesh comprising of up to 5 million nodes is generated to resolve these features with very high accuracy, while maintaining fairly coarse resolution in rest of the domain. The model is configured to run in barotropic mode by forcing harmonic oscillations from FES2012 global <span class="hlt">tide</span> predictions along open boundaries, adjusted to account for volume transport at key channels in the SCS. Computed surface elevations and currents agree well with available <span class="hlt">tide</span> predictions and measurements. Sensitivity study is performed to analyze the role of the small bathymetry features on distorting <span class="hlt">tides</span> in the SCS.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2009EGUGA..11.6378A','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2009EGUGA..11.6378A"><span>New insights into ocean <span class="hlt">tide</span> loading corrections on tidal gravity data in Canary Islands</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Arnoso, J.; Benavent, M.; Bos, M. S.; Montesinos, F. G.</p> <p>2009-04-01</p> <p>The Canary Islands are an interesting area to investigate ocean <span class="hlt">tides</span> loading effects due to the complex coastline of the islands and the varying bathymetry. We present here the quality of five recent global oceanic tidal models, GOT00.2, GOT4.7, FES2004, TPXO.7.1 and AG2006, by comparing their predicted ocean <span class="hlt">tide</span> loading values with results from tidal gravity observations made on three islands, Lanzarote, Tenerife and El Hierro, for the four harmonic constituents O1, K1, M2 and S2. In order to improve the accuracy of the loading corrections on the gravity <span class="hlt">tide</span> measurements, we have used the high resolution regional oceanic model CIAM2 to supplement the global models considered here. This regional model has been obtained by assimilating TOPEX/Poseidon altimetry at crossovers and along-track points and <span class="hlt">tide</span> gauge observations into a hydrodynamic model. The model has a 5'Ã-5' resolution and covers the area between the coordinates 26°.5N to 30°.0N and 19°.0W to 12°.5W. The gravity <span class="hlt">tide</span> observing sites have been occupied by three different LaCoste&Romberg (LCR) spring gravimeters during different periods of observation. We considered here the most recent gravity <span class="hlt">tide</span> observations made with LCR Graviton-EG1194 in El Hierro Island, for a period of 6 months during 2008. In the case of Tenerife and Lanzarote sites we have used observation periods of 6 months and 8 years with LCR-G665 and LCR-G434 gravimeters, respectively. The last two sites have been revisited in order to improve the previous tidal analysis results. Thus, the gravity ocean <span class="hlt">tide</span> loading corrections, based on the five global ocean <span class="hlt">tide</span> models supplemented with the regional model CIAM2 allowed us to review the normalization factors (scale factor and phase lag) of both two gravimeters. Also, we investigated the discrepancies of the corrected gravimetric factors with the DDW elastic and inelastic non hydrostatic body <span class="hlt">tide</span> model (Dehant et al., 1999). The lowest values are found for inelastic model in the</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014EGUGA..1613307H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014EGUGA..1613307H"><span>Detection and attribution of extreme <span class="hlt">weather</span> disasters</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Huggel, Christian; Stone, Dáithí; Hansen, Gerrit</p> <p>2014-05-01</p> <p>Single disasters related to extreme <span class="hlt">weather</span> events have caused loss and damage on the order of up to tens of billions US dollars over the past years. Recent disasters fueled the debate about whether and to what extent these events are related to climate change. In international climate negotiations disaster loss and damage is now high on the agenda, and related policy mechanisms have been discussed or are being implemented. In view of funding allocation and effective risk reduction strategies detection and attribution to climate change of extreme <span class="hlt">weather</span> events and disasters is a key issue. Different avenues have so far been taken to address detection and attribution in this context. Physical climate sciences have developed approaches, among others, where <span class="hlt">variables</span> that are reasonably sampled over climatically relevant time periods and related to the meteorological characteristics of the extreme event are examined. Trends in these <span class="hlt">variables</span> (e.g. air or sea surface temperatures) are compared between observations and climate simulations with and without anthropogenic forcing. Generally, progress has been made in recent years in attribution of changes in the chance of some single extreme <span class="hlt">weather</span> events to anthropogenic climate change but there remain important challenges. A different line of research is primarily concerned with losses related to the extreme <span class="hlt">weather</span> events over time, using disaster databases. A growing consensus is that the increase in asset values and in exposure are main drivers of the strong increase of economic losses over the past several decades, and only a limited number of studies have found trends consistent with expectations from climate change. Here we propose a better integration of existing lines of research in detection and attribution of extreme <span class="hlt">weather</span> events and disasters by applying a risk framework. Risk is thereby defined as a function of the probability of occurrence of an extreme <span class="hlt">weather</span> event, and the associated consequences</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19900048388&hterms=rate+change+frequency&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D20%26Ntt%3Drate%2Bchange%2Bfrequency','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19900048388&hterms=rate+change+frequency&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D20%26Ntt%3Drate%2Bchange%2Bfrequency"><span>Effects of dynamic long-period ocean <span class="hlt">tides</span> on changes in earth's rotation rate</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Nam, Young; Dickman, S. R.</p> <p>1990-01-01</p> <p>As a generalization of the zonal response coefficient first introduced by Agnew and Farrell (1978), the zonal response function kappa of the solid earth-ocean system is defined as the ratio, in the frequency domain, of the tidal change in earth's rotation rate to the <span class="hlt">tide</span>-generating potential. Amplitudes and phases of kappa for the monthly, fortnightly, and nine-day lunar <span class="hlt">tides</span> are estimated from 2 1/2 years of VLBI UT1 observations, corrected for atmospheric angular momentum effects using NMC wind and pressure series. Using the dynamic ocean <span class="hlt">tide</span> model of Dickman (1988, 1989), amplitudes and phases of kappa for an elastic earth-ocean system are predicted. The predictions confirm earlier results which found that dynamic effects of the longer-period ocean <span class="hlt">tides</span> reduce the amplitude of kappa by about 1 percent.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017AGUFMOS23B1403G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017AGUFMOS23B1403G"><span>Design and skill assessment of an Operational Forecasting System for currents and sea level <span class="hlt">variability</span> to the Santos Estuarine System - Brazil</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Godoi Rezende Costa, C.; Castro, B. M.; Blumberg, A. F.; Leite, J. R. B., Sr.</p> <p>2017-12-01</p> <p>Santos City is subject to an average of 12 storm <span class="hlt">tide</span> events per year. Such events bring coastal flooding able to threat human life and damage coastal infrastructure. Severe events have forced the interruption of ferry boat services and ship traffic through Santos Harbor, causing great impacts to Santos Port, the largest in South America, activities. Several studies have focused on the hydrodynamics of storm <span class="hlt">tide</span> events but only a few of those studies have pursued an operational initiative to predict short term (< 3 days) sea level <span class="hlt">variability</span>. The goals of this study are (i) to describe the design of an operational forecasting system built to predict sea surface elevation and currents in the Santos Estuarine System and (ii) to evaluate model performance in simulating observed sea surface elevation. The Santos Operational Forecasting System (SOFS) hydrodynamic module is based on the Stevens Institute Estuarine and Coastal Ocean Model (sECOM). The fully automated SOFS is designed to provide up to 71 h forecast of sea surface elevations and currents every day. The system automatically collects results from global models to run the SOFS nested into another sECOM based model for the South Brazil Bight (SBB). Global forecasting results used to force both models come from Mercator Ocean, released by Copernicus Marine Service, and from the Brazilian developments on the Regional Atmospheric Modeling System (BRAMS) stablished by the Center for <span class="hlt">Weather</span> Forecasts and Climate Studies (with Portuguese acronym CPTEC). The complete routines task take about 8 hours of run time to finish. SOFS was able to hindcast a severe storm <span class="hlt">tide</span> event that took place in Santos on August 21-22, 2016. Comparisons with observed sea level provided skills of 0.92 and maximum root mean square errors of 25 cm. The good agreement with observed data shows the potential of the designed system to predict storm <span class="hlt">tides</span> and to support both human and assets protection.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018PApGe.175.1659R','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018PApGe.175.1659R"><span>Interferometric Water Level Tilt Meter Development in Finland and Comparison with Combined Earth <span class="hlt">Tide</span> and Ocean Loading Models</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Ruotsalainen, Hannu</p> <p>2018-05-01</p> <p>A modern third-generation interferometric water level tilt meter was developed at the Finnish Geodetic Institute in 2000. The tilt meter has absolute scale and can do high-precision tilt measurements on earth <span class="hlt">tides</span>, ocean <span class="hlt">tide</span> loading and atmospheric loading. Additionally, it can be applied in various kinds of geodynamic and geophysical research. The principles and results of the historical 100-year-old Michelson-Gale tilt meter, as well as the development of interferometric water tube tilt meters of the Finnish Geodetic Institute, Finland, are reviewed. Modern Earth <span class="hlt">tide</span> model tilt combined with Schwiderski ocean <span class="hlt">tide</span> loading model explains the uncertainty in historical tilt observations by Michelson and Gale. Earth <span class="hlt">tide</span> tilt observations in Lohja2 geodynamic station, southern Finland, are compared with the combined model earth <span class="hlt">tide</span> and four ocean <span class="hlt">tide</span> loading models. The observed diurnal and semidiurnal harmonic constituents do not fit well with combined models. The reason could be a result of the improper harmonic modelling of the Baltic Sea <span class="hlt">tides</span> in those models.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=20020073397&hterms=oceans+tide&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D80%26Ntt%3Doceans%2Btide','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=20020073397&hterms=oceans+tide&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D80%26Ntt%3Doceans%2Btide"><span>Polar Motion Constraints on Models of the Fortnightly <span class="hlt">Tide</span></span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Ray, Richard D.; Egbert, G. D.; Smith, David E. (Technical Monitor)</p> <p>2002-01-01</p> <p>Estimates of the near-fortnightly Mf ocean <span class="hlt">tide</span> from Topex/Poseidon satellite altimetry and from numerical solutions to the shallow water equations agree reasonably well, at least in their basin-scale features. For example, both show that the Pacific Ocean <span class="hlt">tide</span> lags the Atlantic <span class="hlt">tide</span> by roughly 30 degrees. There are hints of finer scale agreements in the elevation fields, but noise levels are high. In contrast, estimates of Mf currents are only weakly constrained by the TP data, because high-wavenumber Rossby waves (with intense currents) are associated with relatively small perturbations in surface elevation. As a result, a wide range of Mf current fields are consistent with both the TP data and the hydrodynamic equations within a priori plausible misfit bounds. We find that a useful constraint on the Mf currents is provided by independent estimates of the Earth's polar motion. At the Mf period polar motion shows a weak signal (both prograde and retrograde) which must be almost entirely caused by the ocean <span class="hlt">tide</span>. We have estimated this signal from the SPACE2000 time series, after applying a broad-band correction for atmospheric angular momentum. Although the polar motion estimates have relatively large uncertainties, they are sufficiently precise to fix optimum data weights in a global ocean inverse model of Mf. These weights control the tradeoff between fitting a prior hydrodynamic model of Mf and fitting the relatively noisy T/P measurements of Mf. The predicted polar motion from the final inverse model agrees remarkably well with the Mf polar motion observations. The preferred model is also consistent with noise levels suggested by island gauges, and it is marginally consistent with differences observed by subsetting the altimetry (to the small extent that this is possible). In turn, this new model of the Mf ocean <span class="hlt">tide</span> allows the ocean component to be removed from Mf estimates of length of day, thus yielding estimates of complex Love numbers less contaminated by</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014ascl.soft08005P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014ascl.soft08005P"><span>POET: Planetary Orbital Evolution due to <span class="hlt">Tides</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Penev, Kaloyan</p> <p>2014-08-01</p> <p>POET (Planetary Orbital Evolution due to <span class="hlt">Tides</span>) calculates the orbital evolution of a system consisting of a single star with a single planet in orbit under the influence of <span class="hlt">tides</span>. The following effects are The evolutions of the semimajor axis of the orbit due to the tidal dissipation in the star and the angular momentum of the stellar convective envelope by the tidal coupling are taken into account. In addition, the evolution includes the transfer of angular momentum between the stellar convective and radiative zones, effect of the stellar evolution on the tidal dissipation efficiency, and stellar core and envelope spins and loss of stellar convective zone angular momentum to a magnetically launched wind. POET can be used out of the box, and can also be extended and modified.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/29749219','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/29749219"><span>[Influences of <span class="hlt">tide</span> on silicon and nitrogen contents in soil and porewater in the Minjiang Ri-ver estuary, Southeast China].</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Hou, Guan Yun; Zhai, Shui Jing; Le, Xiao Qing; Tong, Chuan</p> <p>2017-01-01</p> <p>Taking Shanyuntan wetland in the Minjiang River estuary as test object, the dissolved silicates (DSi) and inorganic nitrogen contents in porewater and the biogenic silica (BSi) and total nitrogen contents in surface soil of the Phragmites australis wetland, Cyperus malaccensis wetland and Spartina alterniflora wetland were measured in October 2014 (spring <span class="hlt">tide</span> month) and April 2015 (neap <span class="hlt">tide</span> month), respectively, to illuminate the influence of <span class="hlt">tide</span> on silicon and nitrogen contents in soil and porewater of estuarine wetland. Results showed that the DSi content in porewater and the BSi content in surface soil in spring <span class="hlt">tide</span> month were slightly higher than those in neap <span class="hlt">tide</span> month, with the highest being observed on neap <span class="hlt">tide</span> day and the lowest occurring on spring <span class="hlt">tide</span> day. In contrast, the BSi content in surface soil on spring <span class="hlt">tide</span> day showed an opposite trend with that on neap <span class="hlt">tide</span> day. The contents of NH 4 + -N and NO 3 - -N in porewater of different wetland soils in spring <span class="hlt">tide</span> month were higher than those in neap <span class="hlt">tide</span> month, while the content of NH 4 + -N on spring <span class="hlt">tide</span> day was significantly higher than that on neap <span class="hlt">tide</span> day (P<0.05). The study found that hydrological conditions such as flooding duration and drying-wetting alternation caused by <span class="hlt">tide</span> had great influences on silicon and nitrogen contents in porewater and surface soil, and vegetation types also showed great influences on their distributions in intertidal wetland of the Minjiang River estuary.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2005GeoRL..32.9603M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2005GeoRL..32.9603M"><span><span class="hlt">Tide</span> gauge observations of the Indian Ocean tsunami, December 26, 2004</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Merrifield, M. A.; Firing, Y. L.; Aarup, T.; Agricole, W.; Brundrit, G.; Chang-Seng, D.; Farre, R.; Kilonsky, B.; Knight, W.; Kong, L.; Magori, C.; Manurung, P.; McCreery, C.; Mitchell, W.; Pillay, S.; Schindele, F.; Shillington, F.; Testut, L.; Wijeratne, E. M. S.; Caldwell, P.; Jardin, J.; Nakahara, S.; Porter, F.-Y.; Turetsky, N.</p> <p>2005-05-01</p> <p>The magnitude 9.0 earthquake centered off the west coast of northern Sumatra (3.307°N, 95.947°E) on December 26, 2004 at 00:59 UTC (United States Geological Survey (USGS) (2005), USGS Earthquake Hazards Program-Latest Earthquakes, Earthquake Hazards Program, http://earthquake.usgs.gov/eqinthenews/2004/usslav/, 2005) generated a series of tsunami waves that devastated coastal areas throughout the Indian Ocean. <span class="hlt">Tide</span> gauges operated on behalf of national and international organizations recorded the wave form at a number of island and continental locations. This report summarizes the <span class="hlt">tide</span> gauge observations of the tsunami in the Indian Ocean (available as of January 2005) and provides a recommendation for the use of the basin-wide <span class="hlt">tide</span> gauge network for future warnings.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/27449556','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/27449556"><span>Sunshine on my shoulders: <span class="hlt">Weather</span>, pollution, and emotional distress.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Beecher, Mark E; Eggett, Dennis; Erekson, Davey; Rees, Lawrence B; Bingham, Jennie; Klundt, Jared; Bailey, Russell J; Ripplinger, Clark; Kirchhoefer, Jessica; Gibson, Robert; Griner, Derek; Cox, Jonathan C; Boardman, R D</p> <p>2016-11-15</p> <p>Researchers have examined the relationship between mental health and <span class="hlt">weather</span>/pollution with mixed results. The current study aimed to examine a range of <span class="hlt">weather</span> and atmospheric phenomena and their association with time-bound mental health data. Nineteen different <span class="hlt">weather</span>/pollution <span class="hlt">variables</span> were examined in connection with an archive of self-reported mental health data for university students participating in mental health treatment (n=16,452) using the Outcome Questionnaire 45.2 (OQ-45). Statistical approach involved randomly selecting 500 subjects from the sample 1000 different times and testing each <span class="hlt">variable</span> of interest using mixed models analyses. Seasonal changes in sun time were found to best account for relationships between <span class="hlt">weather</span> <span class="hlt">variables</span> and <span class="hlt">variability</span> in mental health distress. Increased mental health distress was found during periods of reduced sun time hours. A separate analysis examining subjects' endorsement of a suicidality item, though not statistically significant, demonstrated a similar pattern. Initial results showed a relationship between pollution and changes in mental health distress; however, this was mediated by sun time. This study examined a relatively homogenous, predominantly European American, and religious sample of college counseling clients from an area that is subject to inversions and is at a high altitude and a latitude where sun time vacillates significantly more than locations closer to the equator. Seasonal increases in sun time were associated with decreased mental health distress. This suggests the need for institutions and public health entities to plan for intervention and prevention resources and strategies during periods of reduced sun time. Copyright © 2016 Elsevier B.V. All rights reserved.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2010EGUGA..12.4662C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2010EGUGA..12.4662C"><span>Evaluation of sediment transport at a fetch-limited beach from spring to neap <span class="hlt">tide</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Carrasco, Ana Rita; Ferreira, Óscar; Matias, Ana; Freire, Paula; Alveirinho Dias, João.</p> <p>2010-05-01</p> <p>Sediment transport studies are useful tools for the determination of sediment budgets, important in the definition of management policies, in particular in environments not fully understood like fetch-limited beaches. Only a few studies have been made with respect to these beaches, and research efforts need to be continued to correctly quantify the main factors governing morphological changes. The present study provides new insights on sediment transport at a fetch-limited backbarrier beach located at the Peninsula do Ancão (Ria Formosa, South of Portugal). The field site extends over ~150 m and includes a sandy beach with a low and narrow reflective morphology, and an external sand bank at the seaward edge of the sub-aerial beach profile. Fluorescent tracers were used to measure the short-term sediment transport (rates and directions) from spring to neap <span class="hlt">tides</span>, for fair-<span class="hlt">weather</span> conditions. The experiment was set at two beach morphologies: beach face and sand bank. Tracer was released on 20th March 2008 at both sites, and sampling was conducted at low <span class="hlt">tide</span>, each 24h, during 7 days. In situ fluorescent tracer detection was performed with UV light. Currents were obtained with a portable single-axis electromagnetic current meter located at the beach face, and an Aquadopp Profiler located at the sand bank. Local waves were obtained by numerical modelling for the study area, based on prevailing winds (measured by a nearby meteorological station), and using available bathymetric surveys. Tracer trends, tidal currents, wind conditions and waves were integrative in order to determine to which forcing mechanism the beach morphology was more responsive. Daily wind intensities were, in average, close to 5 m/s, and maximum estimated significant wave height (Hs) did not exceed 0.045 m. Daily mean wave period ranged from 0.5 s to 0.7 s. The maximum tidal range was 2.8 m. Currents were of higher magnitude at the sand bank than at the beach face, with the maximum during ebb <span class="hlt">tide</span></p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/26594699','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/26594699"><span>Impacts of <span class="hlt">weather</span> on long-term patterns of plant richness and diversity vary with location and management.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Jonas, Jayne L; Buhl, Deborah A; Symstad, Amy J</p> <p>2015-09-01</p> <p>Better understanding the influence of precipitation and temperature on plant assemblages is needed to predict the effects of climate change. Many studies have examined the relationship between plant productivity and <span class="hlt">weather</span> (primarily precipitation), but few have directly assessed the relationship between plant richness or diversity and <span class="hlt">weather</span> despite their increased use as metrics of ecosystem condition. We focus on the grasslands of central North America, which are characterized by high temporal climatic <span class="hlt">variability</span>. Over the next 100 years, these grasslands are predicted to experience further increased <span class="hlt">variability</span> in growing season precipitation, as well as increased temperatures, due to global climate change. We assess the portion of interannual <span class="hlt">variability</span> of richness and diversity explained by <span class="hlt">weather</span>, how relationships between these metrics and <span class="hlt">weather</span> vary among plant assemblages, and which aspects of <span class="hlt">weather</span> best explain temporal <span class="hlt">variability</span>. We used an information-theoretic approach to assess relationships between long-term plant richness and diversity patterns and a priori <span class="hlt">weather</span> covariates using six data sets from four grasslands. <span class="hlt">Weather</span> explained up to 49% and 63% of interannual <span class="hlt">variability</span> in total plant species richness and diversity, respectively. However, richness and diversity responses to specific <span class="hlt">weather</span> <span class="hlt">variables</span> varied both among sites and among experimental treatments within sites. In general, we found many instances in which temperature was of equal or greater importance as precipitation, as well as evidence of the importance of lagged effects and precipitation or temperature <span class="hlt">variability</span>. Although precipitation has been shown to be a key driver of productivity in grasslands, our results indicate that increasing temperatures alone, without substantial changes in precipitation patterns, could have measurable effects on Great Plains grassland plant assemblages and biodiversity metrics. Our results also suggest that richness and diversity</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/27980016','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/27980016"><span>Acute Low Back Pain? Do Not Blame the <span class="hlt">Weather</span>-A Case-Crossover Study.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Beilken, Keira; Hancock, Mark J; Maher, Chris G; Li, Qiang; Steffens, Daniel</p> <p>2017-06-01</p> <p>To investigate the influence of various <span class="hlt">weather</span> parameters on the risk of developing a low back pain (LBP) episode. Case-crossover study. Primary care clinics in Sydney, Australia. 981 participants with a new episode of acute LBP. <span class="hlt">Weather</span> parameters were obtained from the Australian Bureau of Meteorology. Odds ratios (OR) and 95% confidence intervals (95% CI) were derived comparing two exposure <span class="hlt">variables</span> in the case window-(1) the average of the <span class="hlt">weather</span> <span class="hlt">variable</span> for the day prior to pain onset and (2) the change in the <span class="hlt">weather</span> <span class="hlt">variable</span> from 2 days prior to 1 day prior to pain onset-with exposures in two control windows (1 week and 1 month before the case window). The <span class="hlt">weather</span> parameters of precipitation, humidity, wind speed, wind gust, wind direction, and air pressure were not associated with the onset of acute LBP. For one of the four analyses, higher temperature slightly increased the odds of pain onset. Common <span class="hlt">weather</span> parameters that had been previously linked to musculoskeletal pain, such as precipitation, humidity, wind speed, wind gust, wind direction, and air pressure, do not increase the risk of onset for LBP. © 2016 American Academy of Pain Medicine. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li class="active"><span>22</span></li> <li><a href="#" onclick='return showDiv("page_23");'>23</a></li> <li><a href="#" onclick='return showDiv("page_24");'>24</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_22 --> <div id="page_23" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li class="active"><span>23</span></li> <li><a href="#" onclick='return showDiv("page_24");'>24</a></li> <li><a href="#" onclick='return showDiv("page_25");'>25</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="441"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20110008283','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20110008283"><span>The Contribution of Io-Raised <span class="hlt">Tides</span> to Europa's Diurnally-Varying Surface Stresses</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Rhoden, Alyssa Rose; Hurford, Terry A,; Manga, Michael</p> <p>2011-01-01</p> <p>Europa's icy surface records a rich history of geologic activity, Several features appear to be tectonic in origin and may have formed in response to Europa's daily-varying tidal stress [I]. Strike-slip faults and arcuate features called cycloids have both been linked to the patterns of stress change caused by eccentricity and obliquity [2J[3]. In fact, as Europa's obliquity has not been directly measured, observed tectonic patterns arc currently the best indicators of a theoretically supported [4] non-negligible obliquity. The diurnal tidal stress due to eccentricity is calculated by subtracting the average (or static) tidal shape of Europa generated by Jupiter's gravitational field from the instantaneous shape, which varies as Europa moves through its eccentric orbit [5]. In other words, it is the change of shape away from average that generates tidal stress. One might expect tidal contributions from the other large moons of Jupiter to be negligible given their size and the height of the <span class="hlt">tides</span> they raise on Europa versus Jupiter's mass and the height of the <span class="hlt">tide</span> it raises on Europa, However, what matters for tidally-induced stress is not how large the lo-raised bulge is compared to the Jupiter-raised bulge but rather the differences bet\\Veen the instantaneous and static bulges in each case. For example, when Europa is at apocenter, Jupiter raises a <span class="hlt">tide</span> 30m lower than its static <span class="hlt">tide</span>. At the same time, 10 raises a <span class="hlt">tide</span> about 0.5m higher than its static <span class="hlt">tide</span>. Hence, the change in Io's tidal distortion is about 2% of the change in the Jovian distortion when Europa is at apocenter</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2010ems..confE.128H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2010ems..confE.128H"><span>WIRE: <span class="hlt">Weather</span> Intelligence for Renewable Energies</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Heimo, A.; Cattin, R.; Calpini, B.</p> <p>2010-09-01</p> <p>Renewable energies such as wind and solar energy will play an important, even decisive role in order to mitigate and adapt to the projected dramatic consequences to our society and environment due to climate change. Due to shrinking fossil resources, the transition to more and more renewable energy shares is unavoidable. But, as wind and solar energy are strongly dependent on highly <span class="hlt">variable</span> <span class="hlt">weather</span> processes, increased penetration rates will also lead to strong fluctuations in the electricity grid which need to be balanced. Proper and specific forecasting of ‘energy <span class="hlt">weather</span>' is a key component for this. Therefore, it is today appropriate to scientifically address the requirements to provide the best possible specific <span class="hlt">weather</span> information for forecasting the energy production of wind and solar power plants within the next minutes up to several days. Towards such aims, <span class="hlt">Weather</span> Intelligence will first include developing dedicated post-processing algorithms coupled with <span class="hlt">weather</span> prediction models and with past and/or online measurement data especially remote sensing observations. Second, it will contribute to investigate the difficult relationship between the highly intermittent <span class="hlt">weather</span> dependent power production and concurrent capacities such as transport and distribution of this energy to the end users. Selecting, resp. developing surface-based and satellite remote sensing techniques well adapted to supply relevant information to the specific post-processing algorithms for solar and wind energy production short-term forecasts is a major task with big potential. It will lead to improved energy forecasts and help to increase the efficiency of the renewable energy productions while contributing to improve the management and presumably the design of the energy grids. The second goal will raise new challenges as this will require first from the energy producers and distributors definitions of the requested input data and new technologies dedicated to the management of</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19950049124&hterms=geocentric+approach&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D40%26Ntt%3Dgeocentric%2Bapproach','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19950049124&hterms=geocentric+approach&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D40%26Ntt%3Dgeocentric%2Bapproach"><span>Determination of ocean <span class="hlt">tides</span> from the first year of TOPEX/POSEIDON altimeter measurements</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Ma, X. C.; Shum, C. K.; Eanes, R. J.; Tapley, B. D.</p> <p>1994-01-01</p> <p>An improved geocentric global ocean <span class="hlt">tide</span> model has been determined using 1 year of TOPEX/POSEIDON altimeter measurements to provide corrections to the Cartwright and Ray (1991) model (CR91). The corrections were determined on a 3 deg x 3 deg grid using both the harmonic analysis method and the response method. The two approaches produce similar solutions. The effect on the <span class="hlt">tide</span> solution of simultaneously adjusting radial orbit correction parameters using altimeter measurements was examined. Four semidiurnal (N(sub 2), M(sub 2), S(sub 2) and K(sub 2)), four diurnal (Q(sdub 1), O(sub 1), P(sub 1), and K(sub 1)), and three long-period (S(sub sa), M(sub m), and M(sub f)) constituents, along with the variations at the annual frequency, were included in the harmomnic analysis solution. The observed annual variations represents the first global measurement describing accurate seasonal changes of the ocean during an El Nino year. The corrections to the M(sub 2) constituent have an root mean square (RMS) of 3.6 cm and display a clear banding pattern with regional highs and lows reaching 8 cm. The improved <span class="hlt">tide</span> model reduces the weighted altimeter crossover residual from 9.8 cm RMS, when the CR91 <span class="hlt">tide</span> model is used, to 8.2 cm on RMS. Comparison of the improved model to pelagic tidal constants determined from 80 <span class="hlt">tide</span> gauges gives RMS differences of 2.7 cm for M(sub 2) and 1.7 cm for K(sub 1). Comparable values when the CR91 model is used are 3.9 cm and 2.0 cm, respectively. Examination of TOPEX/POSEIDON sea level anomaly variations using the new <span class="hlt">tide</span> model further confirms that the <span class="hlt">tide</span> model has been improved.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018PhRvD..97f3527A','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018PhRvD..97f3527A"><span>Impact of large-scale <span class="hlt">tides</span> on cosmological distortions via redshift-space power spectrum</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Akitsu, Kazuyuki; Takada, Masahiro</p> <p>2018-03-01</p> <p>Although large-scale perturbations beyond a finite-volume survey region are not direct observables, these affect measurements of clustering statistics of small-scale (subsurvey) perturbations in large-scale structure, compared with the ensemble average, via the mode-coupling effect. In this paper we show that a large-scale <span class="hlt">tide</span> induced by scalar perturbations causes apparent anisotropic distortions in the redshift-space power spectrum of galaxies in a way depending on an alignment between the <span class="hlt">tide</span>, wave vector of small-scale modes and line-of-sight direction. Using the perturbation theory of structure formation, we derive a response function of the redshift-space power spectrum to large-scale <span class="hlt">tide</span>. We then investigate the impact of large-scale <span class="hlt">tide</span> on estimation of cosmological distances and the redshift-space distortion parameter via the measured redshift-space power spectrum for a hypothetical large-volume survey, based on the Fisher matrix formalism. To do this, we treat the large-scale <span class="hlt">tide</span> as a signal, rather than an additional source of the statistical errors, and show that a degradation in the parameter is restored if we can employ the prior on the rms amplitude expected for the standard cold dark matter (CDM) model. We also discuss whether the large-scale <span class="hlt">tide</span> can be constrained at an accuracy better than the CDM prediction, if the effects up to a larger wave number in the nonlinear regime can be included.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/17650866','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/17650866"><span>[Relationships between pollutants discharge and red <span class="hlt">tide</span> occurrence in Shenzhen eastern coast].</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Jiang, Tian-jiu; Niu, Tao; Ying, Wen-ye</p> <p>2007-05-01</p> <p>The study on the effects of pollutants discharge on red <span class="hlt">tide</span> occurrence in eastern sea area of Shenzhen showed that the occurrence frequency of dinoflagellate red <span class="hlt">tide</span> had significant positive correlations with the net discharge of total nitrogen (TN) and total phosphorous (TP) as well as the N/P ratio of the discharge. The thresholds of net discharged TN and TP were estimated to be 3.917 x 10(3) t and 2.123 x 10(4) t, respectively. No significant correlation was observed between diatom red <span class="hlt">tide</span> and alongshore pollutants discharge. An example was given to illustrate the means of pollutants discharge control.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19940033982&hterms=oceans+tide&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D20%26Ntt%3Doceans%2Btide','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19940033982&hterms=oceans+tide&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D20%26Ntt%3Doceans%2Btide"><span>Diurnal <span class="hlt">tides</span> in the Arctic Ocean</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Kowalik, Z.; Proshutinsky, A. Y.</p> <p>1993-01-01</p> <p>A 2D numerical model with a space grid of about 14 km is applied to calculate diurnal tidal constituents K(1) and O(1) in the Arctic Ocean. Calculated corange and cotidal charts show that along the continental slope, local regions of increased sea level amplitude, highly <span class="hlt">variable</span> phase and enhanced currents occur. It is shown that in these local regions, shelf waves (topographic waves) of tidal origin are generated. In the Arctic Ocean and Northern Atlantic Ocean more than 30 regions of enhanced currents are identified. To prove the near-resonant interaction of the diurnal <span class="hlt">tides</span> with the local bottom topography, the natural periods of oscillations for all regions have been calculated. The flux of energy averaged over the tidal period depicts the gyres of semitrapped energy, suggesting that the shelf waves are partially trapped over the irregularities of the bottom topography. It is shown that the occurrence of near-resonance phenomenon changes the energy flow in the tidal waves. First, the flux of energy from the astronomical sources is amplified in the shelf wave regions, and afterwards the tidal energy is strongly dissipated in the same regions.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017AGUFMOS21B..07D','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017AGUFMOS21B..07D"><span>Vertical land motion along the coast of Louisiana: Integrating satellite altimetry, <span class="hlt">tide</span> gauge and GPS</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Dixon, T. H.; A Karegar, M.; Uebbing, B.; Kusche, J.; Fenoglio-Marc, L.</p> <p>2017-12-01</p> <p>Coastal Louisiana is experiencing the highest rate of relative sea-level rise in North America due to the combination of sea-level rise and subsidence of the deltaic plain. The land subsidence in this region is studied using various techniques, with continuous GPS site providing high temporal resolution. Here, we use high resolution <span class="hlt">tide</span>-gauge data and advanced processing of satellite altimetry to derive vertical displacements time series at NOAA <span class="hlt">tide</span>-gauge stations along the coast (Figure 1). We apply state-of-the-art retracking techniques to process raw altimetry data, allowing high accuracy on range measurements close to the coast. Data from Jason-1, -2 and -3, Envisat, Saral and Cryosat-2 are used, corrected for solid Earth <span class="hlt">tide</span>, pole <span class="hlt">tide</span> and tidal ocean loading, using background models consistent with the GPS processing technique. We reprocess the available GPS data using precise point positioning and estimate the rate uncertainty accounting for correlated noise. The displacement time series are derived by directly subtracting <span class="hlt">tide</span>-gauge data from the altimetry sea-level anomaly data. The quality of the derived displacement rates is evaluated in Grand Isle, Amerada Pass and Shell Beach where GPS data are available adjacent to the <span class="hlt">tide</span> gauges. We use this technique to infer vertical displacement at <span class="hlt">tide</span> gauges in New Orleans (New Canal Station) and Port Fourchon and Southwest Pass along the coastline.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3014608','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3014608"><span>Review of Florida Red <span class="hlt">Tide</span> and Human Health Effects</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Fleming, Lora E.; Kirkpatrick, Barbara; Backer, Lorraine C.; Walsh, Cathy J.; Nierenberg, Kate; Clark, John; Reich, Andrew; Hollenbeck, Julie; Benson, Janet; Cheng, Yung Sung; Naar, Jerome; Pierce, Richard; Bourdelais, Andrea J; Abraham, William M.; Kirkpatrick, Gary; Zaias, Julia; Wanner, Adam; Mendes, Eliana; Shalat, Stuart; Hoagland, Porter; Stephan, Wendy; Bean, Judy; Watkins, Sharon; Clarke, Tainya; Byrne, Margaret; Baden, Daniel G.</p> <p>2010-01-01</p> <p>This paper reviews the literature describing research performed over the past decade on the known and possible exposures and human health effects associated with Florida red <span class="hlt">tides</span>. These harmful algal blooms are caused by the dinoflagellate, Karenia brevis, and similar organisms, all of which produce a suite of natural toxins known as brevetoxins. Florida red <span class="hlt">tide</span> research has benefited from a consistently funded, long term research program, that has allowed an interdisciplinary team of researchers to focus their attention on this specific environmental issue—one that is critically important to Gulf of Mexico and other coastal communities. This long-term interdisciplinary approach has allowed the team to engage the local community, identify measures to protect public health, take emerging technologies into the field, forge advances in natural products chemistry, and develop a valuable pharmaceutical product. The Review includes a brief discussion of the Florida red <span class="hlt">tide</span> organisms and their toxins, and then focuses on the effects of these toxins on animals and humans, including how these effects predict what we might expect to see in exposed people. PMID:21218152</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/21218152','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/21218152"><span>Review of Florida Red <span class="hlt">Tide</span> and Human Health Effects.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Fleming, Lora E; Kirkpatrick, Barbara; Backer, Lorraine C; Walsh, Cathy J; Nierenberg, Kate; Clark, John; Reich, Andrew; Hollenbeck, Julie; Benson, Janet; Cheng, Yung Sung; Naar, Jerome; Pierce, Richard; Bourdelais, Andrea J; Abraham, William M; Kirkpatrick, Gary; Zaias, Julia; Wanner, Adam; Mendes, Eliana; Shalat, Stuart; Hoagland, Porter; Stephan, Wendy; Bean, Judy; Watkins, Sharon; Clarke, Tainya; Byrne, Margaret; Baden, Daniel G</p> <p>2011-01-01</p> <p>This paper reviews the literature describing research performed over the past decade on the known and possible exposures and human health effects associated with Florida red <span class="hlt">tides</span>. These harmful algal blooms are caused by the dinoflagellate, Karenia brevis, and similar organisms, all of which produce a suite of natural toxins known as brevetoxins. Florida red <span class="hlt">tide</span> research has benefited from a consistently funded, long term research program, that has allowed an interdisciplinary team of researchers to focus their attention on this specific environmental issue-one that is critically important to Gulf of Mexico and other coastal communities. This long-term interdisciplinary approach has allowed the team to engage the local community, identify measures to protect public health, take emerging technologies into the field, forge advances in natural products chemistry, and develop a valuable pharmaceutical product. The Review includes a brief discussion of the Florida red <span class="hlt">tide</span> organisms and their toxins, and then focuses on the effects of these toxins on animals and humans, including how these effects predict what we might expect to see in exposed people.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19960008974','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19960008974"><span>Minutes of TOPEX/POSEIDON Science Working Team Meeting and Ocean <span class="hlt">Tides</span> Workshop</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Fu, Lee-Lueng (Editor)</p> <p>1995-01-01</p> <p>This third TOPEX/POSEIDON Science Working Team meeting was held on December 4, 1994 to review progress in defining ocean <span class="hlt">tide</span> models, precision Earth orbits, and various science algorithms. A related workshop on ocean <span class="hlt">tides</span> convened to select the best models to be used by scientists in the Geophysical Data Records.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.er.usgs.gov/publication/70154925','USGSPUBS'); return false;" href="https://pubs.er.usgs.gov/publication/70154925"><span>Measuring storm <span class="hlt">tide</span> and high-water marks caused by Hurricane Sandy in New York: Chapter 2</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Simonson, Amy E.; Behrens, Riley</p> <p>2015-01-01</p> <p>In response to Hurricane Sandy, personnel from the U.S. Geological Survey (USGS) deployed a temporary network of storm-<span class="hlt">tide</span> sensors from Virginia to Maine. During the storm, real-time water levels were available from <span class="hlt">tide</span> gages and rapid-deployment gages (RDGs). After the storm, USGS scientists retrieved the storm-<span class="hlt">tide</span> sensors and RDGs and surveyed high-water marks. These data demonstrate that the timing of peak storm surge relative to astronomical <span class="hlt">tide</span> was extremely important in southeastern New York. For example, along the south shores of New York City and western Suffolk County, the peak storm surge of 6–9 ft generally coincided with the astronomical high <span class="hlt">tide</span>, which resulted in substantial coastal flooding. In the Peconic Estuary and northern Nassau County, however, the peak storm surge of 9 ft and nearly 12 ft, respectively, nearly coincided with normal low <span class="hlt">tide</span>, which helped spare these communities from more severe coastal flooding.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017JPhCS.910a2020W','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017JPhCS.910a2020W"><span>The <span class="hlt">Weather</span> Forecast Using Data Mining Research Based on Cloud Computing.</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Wang, ZhanJie; Mazharul Mujib, A. B. M.</p> <p>2017-10-01</p> <p><span class="hlt">Weather</span> forecasting has been an important application in meteorology and one of the most scientifically and technologically challenging problem around the world. In my study, we have analyzed the use of data mining techniques in forecasting <span class="hlt">weather</span>. This paper proposes a modern method to develop a service oriented architecture for the <span class="hlt">weather</span> information systems which forecast <span class="hlt">weather</span> using these data mining techniques. This can be carried out by using Artificial Neural Network and Decision tree Algorithms and meteorological data collected in Specific time. Algorithm has presented the best results to generate classification rules for the mean <span class="hlt">weather</span> <span class="hlt">variables</span>. The results showed that these data mining techniques can be enough for <span class="hlt">weather</span> forecasting.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://files.eric.ed.gov/fulltext/ED417092.pdf','ERIC'); return false;" href="http://files.eric.ed.gov/fulltext/ED417092.pdf"><span><span class="hlt">Weather</span>.</span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Ruth, Amy, Ed.</p> <p>1996-01-01</p> <p>This theme issue of "The Goldfinch" focuses on <span class="hlt">weather</span> in Iowa and <span class="hlt">weather</span> lore. The bulletin contains historical articles, fiction, activities, and maps. The table of contents lists: (1) "Wild Rosie's Map"; (2) "History Mystery"; (3) "Iowa's <span class="hlt">Weather</span> History"; (4) "<span class="hlt">Weather</span> Wonders"; (6)…</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=2773792','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=2773792"><span><span class="hlt">TIde</span>: a software for the systematic scanning of drug targets in kinetic network models</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Schulz, Marvin; Bakker, Barbara M; Klipp, Edda</p> <p>2009-01-01</p> <p>Background During the stages of the development of a potent drug candidate compounds can fail for several reasons. One of them, the efficacy of a candidate, can be estimated in silico if an appropriate ordinary differential equation model of the affected pathway is available. With such a model at hand it is also possible to detect reactions having a large effect on a certain <span class="hlt">variable</span> such as a substance concentration. Results We show an algorithm that systematically tests the influence of activators and inhibitors of different type and strength acting at different positions in the network. The effect on a quantity to be selected (e.g. a steady state flux or concentration) is calculated. Moreover, combinations of two inhibitors or one inhibitor and one activator targeting different network positions are analysed. Furthermore, we present <span class="hlt">TIde</span> (Target Identification), an open source, platform independent tool to investigate ordinary differential equation models in the common systems biology markup language format. It automatically assigns the respectively altered kinetics to the inhibited or activated reactions, performs the necessary calculations, and provides a graphical output of the analysis results. For illustration, <span class="hlt">TIde</span> is used to detect optimal inhibitor positions in simple branched networks, a signalling pathway, and a well studied model of glycolysis in Trypanosoma brucei. Conclusion Using <span class="hlt">TIde</span>, we show in the branched models under which conditions inhibitions in a certain pathway can affect a molecule concentrations in a different. In the signalling pathway we illuminate which inhibitions have an effect on the signalling characteristics of the last active kinase. Finally, we compare our set of best targets in the glycolysis model with a similar analysis showing the applicability of our tool. PMID:19840374</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016JGeod..90.1237M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016JGeod..90.1237M"><span>High-frequency Earth rotation variations deduced from altimetry-based ocean <span class="hlt">tides</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Madzak, Matthias; Schindelegger, Michael; Böhm, Johannes; Bosch, Wolfgang; Hagedoorn, Jan</p> <p>2016-11-01</p> <p>A model of diurnal and semi-diurnal variations in Earth rotation parameters (ERP) is constructed based on altimetry-measured tidal heights from a multi-mission empirical ocean <span class="hlt">tide</span> solution. Barotropic currents contributing to relative angular momentum changes are estimated for nine major <span class="hlt">tides</span> in a global inversion algorithm that solves the two-dimensional momentum equations on a regular 0.5° grid with a heavily weighted continuity constraint. The influence of 19 minor <span class="hlt">tides</span> is accounted for by linear admittance interpolation of ocean tidal angular momentum, although the assumption of smooth admittance variations with frequency appears to be a doubtful concept for semi-diurnal mass terms in particular. A validation of the newly derived model based on post-fit corrections to polar motion and universal time (Δ UT1) from the analysis of Very Long Baseline Interferometry (VLBI) observations shows a variance reduction for semi-diurnal Δ UT1 residuals that is significant at the 0.05 level with respect to the conventional ERP model. Improvements are also evident for the explicitly modeled K_1, Q_1, and K_2 <span class="hlt">tides</span> in individual ERP components, but large residuals of more than 15 μ as remain at the principal lunar frequencies of O_1 and M_2. We attribute these shortcomings to uncertainties in the inverted relative angular momentum changes and, to a minor extent, to violation of mass conservation in the empirical ocean <span class="hlt">tide</span> solution. Further dedicated hydrodynamic modeling efforts of these anomalous constituents are required to meet the accuracy standards of modern space geodesy.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017ClDy...49.3605K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017ClDy...49.3605K"><span>Long-term change of the atmospheric energy cycles and <span class="hlt">weather</span> disturbances</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Kim, WonMoo; Choi, Yong-Sang</p> <p>2017-11-01</p> <p><span class="hlt">Weather</span> disturbances are the manifestation of mean atmospheric energy cascading into eddies, thus identifying atmospheric energy structure is of fundamental importance to understand the <span class="hlt">weather</span> <span class="hlt">variability</span> in a changing climate. The question is whether our observational data can lead to a consistent diagnosis on the energy conversion characteristics. Here we investigate the atmospheric energy cascades by a simple framework of Lorenz energy cycle, and analyze the energy distribution in mean and eddy fields as forms of potential and kinetic energy. It is found that even the widely utilized independent reanalysis datasets, NCEP-DOE AMIP-II Reanalysis (NCEP2) and ERA-Interim (ERA-INT), draw different conclusions on the change of <span class="hlt">weather</span> <span class="hlt">variability</span> measured by eddy-related kinetic energy. NCEP2 shows an increased mean-to-eddy energy conversion and enhanced eddy activity due to efficient baroclinic energy cascade, but ERA-INT shows relatively constant energy cascading structure between the 1980s and the 2000s. The source of discrepancy mainly originates from the uncertainties in hydrological <span class="hlt">variables</span> in the mid-troposphere. Therefore, much efforts should be made to improve mid-tropospheric observations for more reliable diagnosis of the <span class="hlt">weather</span> disturbances as a consequence of man-made greenhouse effect.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/22505777','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/22505777"><span>Sensitivity of barley varieties to <span class="hlt">weather</span> in Finland.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Hakala, K; Jauhiainen, L; Himanen, S J; Rötter, R; Salo, T; Kahiluoto, H</p> <p>2012-04-01</p> <p>Global climate change is predicted to shift seasonal temperature and precipitation patterns. An increasing frequency of extreme <span class="hlt">weather</span> events such as heat waves and prolonged droughts is predicted, but there are high levels of uncertainty about the nature of local changes. Crop adaptation will be important in reducing potential damage to agriculture. Crop diversity may enhance resilience to climate <span class="hlt">variability</span> and changes that are difficult to predict. Therefore, there has to be sufficient diversity within the set of available cultivars in response to <span class="hlt">weather</span> parameters critical for yield formation. To determine the scale of such '<span class="hlt">weather</span> response diversity' within barley (Hordeum vulgare L.), an important crop in northern conditions, the yield responses of a wide range of modern and historical varieties were analysed according to a well-defined set of critical agro-meteorological <span class="hlt">variables</span>. The Finnish long-term dataset of MTT Official Variety Trials was used together with historical <span class="hlt">weather</span> records of the Finnish Meteorological Institute. The foci of the analysis were firstly to describe the general response of barley to different <span class="hlt">weather</span> conditions and secondly to reveal the diversity among varieties in the sensitivity to each <span class="hlt">weather</span> <span class="hlt">variable</span>. It was established that barley yields were frequently reduced by drought or excessive rain early in the season, by high temperatures at around heading, and by accelerated temperature sum accumulation rates during periods 2 weeks before heading and between heading and yellow ripeness. Low temperatures early in the season increased yields, but frost during the first 4 weeks after sowing had no effect. After canopy establishment, higher precipitation on average resulted in higher yields. In a cultivar-specific analysis, it was found that there were differences in responses to all but three of the studied climatic <span class="hlt">variables</span>: waterlogging and drought early in the season and temperature sum accumulation rate before heading</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.dtic.mil/docs/citations/ADA606524','DTIC-ST'); return false;" href="http://www.dtic.mil/docs/citations/ADA606524"><span>How Stationary Are the Internal <span class="hlt">Tides</span> in a High-Resolution Global Ocean Circulation Model?</span></a></p> <p><a target="_blank" href="http://www.dtic.mil/">DTIC Science & Technology</a></p> <p></p> <p>2014-05-12</p> <p>Egbert et al., 1994] and that the model global internal <span class="hlt">tide</span> amplitudes compare well with an altimetric-based tidal analysis [Ray and Byrne, 2010]. The... analysis [Foreman, 1977] applied to the HYCOM total SSH. We will follow Shriver et al. [2012], analyzing the <span class="hlt">tides</span> along satellite altimeter tracks...spots,’’ the comparison between the model and altimetric analysis is not as good due, in part, to two prob- lems, errors in the model barotropic <span class="hlt">tides</span> and</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2006GeoRL..3311601H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2006GeoRL..3311601H"><span>Hurricanes, submarine groundwater discharge, and Florida's red <span class="hlt">tides</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Hu, Chuanmin; Muller-Karger, Frank E.; Swarzenski, Peter W.</p> <p>2006-06-01</p> <p>A Karenia brevis Harmful Algal Bloom affected coastal waters shallower than 50 m off west-central Florida from January 2005 through January 2006, showing a sustained anomaly of ~1 mg chlorophyll m-3 over an area of up to 67,500 km2. Red <span class="hlt">tides</span> occur in the same area (approximately 26-29°N, 82-83°W) almost every year, but the intense 2005 bloom led to a widespread hypoxic zone (dissolved oxygen <2 mg L-1) that caused mortalities of benthic communities, fish, turtles, birds, and marine mammals. Runoff alone provided insufficient nitrogen to support this bloom. We pose the hypothesis that submarine groundwater discharge (SGD) provides the missing nutrients, and indeed can trigger and support the recurrent red <span class="hlt">tides</span> off west-central Florida. SGD inputs of dissolved inorganic nitrogen (DIN) in Tampa Bay alone are ~35% of that discharged by all central Florida rivers draining west combined. We propose that the unusual number of hurricanes in 2004 resulted in high runoff, and in higher than normal SGD emerging along the west Florida coast throughout 2005, initiating and fueling the persistent HAB. This mechanism may also explain recurrent red <span class="hlt">tides</span> in other coastal regions of the Gulf of Mexico.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.er.usgs.gov/publication/70028072','USGSPUBS'); return false;" href="https://pubs.er.usgs.gov/publication/70028072"><span>Hurricanes, submarine groundwater discharge, and Florida's red <span class="hlt">tides</span></span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Hu, C.; Muller-Karger, F. E.; Swarzenski, P.W.</p> <p>2006-01-01</p> <p>A Karenia brevis Harmful Algal Bloom affected coastal waters shallower than 50 m off west-central Florida from January 2005 through January 2006, showing a sustained anomaly of ???1 mg chlorophyll m-3 over an area of up to 67,500 km2. Red <span class="hlt">tides</span> occur in the same area (approximately 26-29??N, 82-83??W) almost every year, but the intense 2005 bloom led to a widespread hypoxic zone (dissolved oxygen <2 mg L-1) that caused mortalities of benthic communities, fish, turtles, birds, and marine mammals. Runoff alone provided insufficient nitrogen to support this bloom. We pose the hypothesis that submarine groundwater discharge (SGD) provides the missing nutrients, and indeed can trigger and support the recurrent red <span class="hlt">tides</span> off west-central Florida. SGD inputs of dissolved inorganic nitrogen (DIN) in Tampa Bay alone are ???35% of that discharged by all central Florida rivers draining west combined. We propose that the unusual number of hurricanes in 2004 resulted in high runoff, and in higher than normal SGD emerging along the west Florida coast throughout 2005, initiating and fueling the persistent HAB. This mechanism may also explain recurrent red <span class="hlt">tides</span> in other coastal regions of the Gulf of Mexico. Copyright 2006 by the American Geophysical Union.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li class="active"><span>23</span></li> <li><a href="#" onclick='return showDiv("page_24");'>24</a></li> <li><a href="#" onclick='return showDiv("page_25");'>25</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_23 --> <div id="page_24" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li><a href="#" onclick='return showDiv("page_23");'>23</a></li> <li class="active"><span>24</span></li> <li><a href="#" onclick='return showDiv("page_25");'>25</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="461"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1997E%26PSL.153..239F','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1997E%26PSL.153..239F"><span><span class="hlt">Tide</span>-related <span class="hlt">variability</span> of TAG hydrothermal activity observed by deep-sea monitoring system and OBSH</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Fujioka, Kantaro; Kobayashi, Kazuo; Kato, Kazuhiro; Aoki, Misumi; Mitsuzawa, Kyohiko; Kinoshita, Masataka; Nishizawa, Azusa</p> <p>1997-12-01</p> <p>Hydrothermal activities were monitored by an ocean bottom seismometer with hydrophone (OBSH) and a composite measuring system (Manatee) including CTD, current meter, transmission meter and cameras at a small depression on the TAG hydrothermal mound in the Mid-Atlantic Ridge. Low-frequency pressure pulses detected by the hydrophone with semi-diurnal periodicity seem to correspond to cycles of hydrothermal upflow from a small and short-lived smoker vent close to the observing site. The peaks of pressure pulses are synchronous with the maximum gradient of areal strain decrease due to tidal load release. Microearthquakes with very near epicenters occur sporadically and do not appear to be directly correlatable to hydrothermal venting. Temporal variations in bottom water temperature also have semi-diurnal periodicity but are more complicated than the pressure events. Temperatures may be affected both by upwelling of hot water and by lateral flow of the bottom current changing its directions with ocean <span class="hlt">tide</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015AGUFMSH32A..01V','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015AGUFMSH32A..01V"><span>Solar EUV irradiance for space <span class="hlt">weather</span> applications</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Viereck, R. A.</p> <p>2015-12-01</p> <p>Solar EUV irradiance is an important driver of space <span class="hlt">weather</span> models. Large changes in EUV and x-ray irradiances create large <span class="hlt">variability</span> in the ionosphere and thermosphere. Proxies such as the F10.7 cm radio flux, have provided reasonable estimates of the EUV flux but as the space <span class="hlt">weather</span> models become more accurate and the demands of the customers become more stringent, proxies are no longer adequate. Furthermore, proxies are often provided only on a daily basis and shorter time scales are becoming important. Also, there is a growing need for multi-day forecasts of solar EUV irradiance to drive space <span class="hlt">weather</span> forecast models. In this presentation we will describe the needs and requirements for solar EUV irradiance information from the space <span class="hlt">weather</span> modeler's perspective. We will then translate these requirements into solar observational requirements such as spectral resolution and irradiance accuracy. We will also describe the activities at NOAA to provide long-term solar EUV irradiance observations and derived products that are needed for real-time space <span class="hlt">weather</span> modeling.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/23628547','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/23628547"><span>Temporal and spatial distribution of red <span class="hlt">tide</span> outbreaks in the Yangtze River Estuary and adjacent waters, China.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Liu, Lusan; Zhou, Juan; Zheng, Binghui; Cai, Wenqian; Lin, Kuixuan; Tang, Jingliang</p> <p>2013-07-15</p> <p>Between 1972 and 2009, evidence of red <span class="hlt">tide</span> outbreaks in the Yangtze River Estuary and adjacent waters was collected. A geographic information system (GIS) was used to analyze the temporal and spatial distribution of these red <span class="hlt">tides</span>, and it was subsequently used to map the distribution of these events. The results show that the following findings. (1) There were three red <span class="hlt">tide</span>-prone areas: outside the Yangtze River Estuary and the eastern coast of Sheshan, the Huaniaoshan-Shengshan-Gouqi waters, and the Zhoushan areas and eastern coast of Zhujiajian. In these areas, red <span class="hlt">tides</span> occurred 174 total times, 25 of which were larger than 1000 km(2) in areal extent. After 2000, the frequency of red <span class="hlt">tide</span> outbreaks increased significantly. (2) During the months of May and June, the red <span class="hlt">tide</span> occurrence in these areas was 51% and 20%, respectively. (3) Outbreaks of the dominant red <span class="hlt">tide</span> plankton species Prorocentrum dong-haiense, Skeletonema costatum, Prorocentrum dantatum, and Noctiluca scientillan occurred 38, 35, 15, and 10 times, respectively, during the study interval. Copyright © 2013 Elsevier Ltd. All rights reserved.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/18598142','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/18598142"><span><span class="hlt">Tides</span> and the evolution of planetary habitability.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Barnes, Rory; Raymond, Sean N; Jackson, Brian; Greenberg, Richard</p> <p>2008-06-01</p> <p><span class="hlt">Tides</span> raised on a planet by the gravity of its host star can reduce the planet's orbital semi-major axis and eccentricity. This effect is only relevant for planets orbiting very close to their host stars. The habitable zones of low-mass stars are also close in, and <span class="hlt">tides</span> can alter the orbits of planets in these locations. We calculate the tidal evolution of hypothetical terrestrial planets around low-mass stars and show that <span class="hlt">tides</span> can evolve planets past the inner edge of the habitable zone, sometimes in less than 1 billion years. This migration requires large eccentricities (>0.5) and low-mass stars ( less or similar to 0.35 M(circle)). Such migration may have important implications for the evolution of the atmosphere, internal heating, and the Gaia hypothesis. Similarly, a planet that is detected interior to the habitable zone could have been habitable in the past. We consider the past habitability of the recently discovered, approximately 5 M(circle) planet, Gliese 581 c. We find that it could have been habitable for reasonable choices of orbital and physical properties as recently as 2 Gyr ago. However, when constraints derived from the additional companions are included, most parameter choices that indicate past habitability require the two inner planets of the system to have crossed their mutual 3:1 mean motion resonance. As this crossing would likely have resulted in resonance capture, which is not observed, we conclude that Gl 581 c was probably never habitable.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19900043987&hterms=oceans+tide&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D30%26Ntt%3Doceans%2Btide','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19900043987&hterms=oceans+tide&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D30%26Ntt%3Doceans%2Btide"><span>Observations of the Mf ocean <span class="hlt">tide</span> from Geosat altimetry</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Cartwright, David E.; Ray, Richard D.</p> <p>1990-01-01</p> <p>Zonal averages of the 13.66-day Mf <span class="hlt">tide</span> are derived from one year of Geosat altimetry records. The orbit errors are reduced by 1/revolution corrections taken over long (several day) arcs. The short-period <span class="hlt">tides</span> are removed using a model previously derived from the same data. The Mf zonal averages indicate definite nonequilibrium character at nearly all latitudes. The imaginary admittances indicate a Q of at least 8; such a value is consistent with a simplified theory of coupled gravitational and vorticity modes and suggests a value for Proudman's 'friction period' about 123 days.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19890020526','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19890020526"><span>Global behavior of the height/seasonal structure of <span class="hlt">tides</span> between 40 deg and 60 deg latitude</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Manson, A. H.; Meek, C. E.; Teitelbaum, H.; Fraser, G. J.; Smith, M. J.; Clark, R. R.; Schminder, R.; Kuerschner, D.</p> <p>1989-01-01</p> <p>The radars utilized are meteor (2), medium frequency (2) and the new low frequency (1) systems: analysis techniques were exhaustively studied internally and comparatively and are not thought to affect the results. Emphasis is placed upon the new height-time contours of 24-, 12-h tidal amplitudes and phases, which best display height and seasonal structures; where possible high resolution (10 d) is used (Saskatoon), but all stations provide monthly mean resolution. At these latitudes the diurnal <span class="hlt">tide</span> is generally smaller than the semidiurnal, and displays more <span class="hlt">variability</span>. However, there is a tendency for vertical wavelengths and amplitudes to be larger during summer months. On occasions in winter and fall, wavelengths may be less than 50 km. The dominant semidiurnal <span class="hlt">tide</span> shows significant regular season structure; wavelengths are generally small (about 50 km) in winter, large in summer (equal to or greater than 100 km), and these states are separated by rapid equinoctial transitions. There is some evidence for less regularity toward 40 deg. Coupling with mean winds is apparent. Data from earlier ATMAP campaigns are mentioned, and reasons for their inadequacies presented.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016AGUOSPO14A2747A','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016AGUOSPO14A2747A"><span>Accurate Modelling of Surface Currents and Internal <span class="hlt">Tides</span> in a Semi-enclosed Coastal Sea</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Allen, S. E.; Soontiens, N. K.; Dunn, M. B. H.; Liu, J.; Olson, E.; Halverson, M. J.; Pawlowicz, R.</p> <p>2016-02-01</p> <p>The Strait of Georgia is a deep (400 m), strongly stratified, semi-enclosed coastal sea on the west coast of North America. We have configured a baroclinic model of the Strait of Georgia and surrounding coastal waters using the NEMO ocean community model. We run daily nowcasts and forecasts and publish our sea-surface results (including storm surge warnings) to the web (salishsea.eos.ubc.ca/storm-surge). <span class="hlt">Tides</span> in the Strait of Georgia are mixed and large. The baroclinic model and previous barotropic models accurately represent tidal sea-level variations and depth mean currents. The baroclinic model reproduces accurately the diurnal but not the semi-diurnal baroclinic tidal currents. In the Southern Strait of Georgia, strong internal tidal currents at the semi-diurnal frequency are observed. Strong semi-diurnal <span class="hlt">tides</span> are also produced in the model, but are almost 180 degrees out of phase with the observations. In the model, in the surface, the barotropic and baroclinic <span class="hlt">tides</span> reinforce, whereas the observations show that at the surface the baroclinic <span class="hlt">tides</span> oppose the barotropic. As such the surface currents are very poorly modelled. Here we will present evidence of the internal tidal field from observations. We will discuss the generation regions of the <span class="hlt">tides</span>, the necessary modifications to the model required to correct the phase, the resulting baroclinic <span class="hlt">tides</span> and the improvements in the surface currents.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/pages/biblio/1439093-ecohydrologic-processes-soil-thickness-feedbacks-control-limestone-weathering-rates-karst-landscape','SCIGOV-DOEP'); return false;" href="https://www.osti.gov/pages/biblio/1439093-ecohydrologic-processes-soil-thickness-feedbacks-control-limestone-weathering-rates-karst-landscape"><span>Ecohydrologic processes and soil thickness feedbacks control limestone-<span class="hlt">weathering</span> rates in a karst landscape</span></a></p> <p><a target="_blank" href="http://www.osti.gov/pages">DOE PAGES</a></p> <p>Dong, Xiaoli; Cohen, Matthew J.; Martin, Jonathan B.; ...</p> <p>2018-05-18</p> <p>Here, chemical <span class="hlt">weathering</span> of bedrock plays an essential role in the formation and evolution of Earth's critical zone. Over geologic time, the negative feedback between temperature and chemical <span class="hlt">weathering</span> rates contributes to the regulation of Earth climate. The challenge of understanding <span class="hlt">weathering</span> rates and the resulting evolution of critical zone structures lies in complicated interactions and feedbacks among environmental <span class="hlt">variables</span>, local ecohydrologic processes, and soil thickness, the relative importance of which remains unresolved. We investigate these interactions using a reactive-transport kinetics model, focusing on a low-relief, wetland-dominated karst landscape (Big Cypress National Preserve, South Florida, USA) as a case study.more » Across a broad range of environmental <span class="hlt">variables</span>, model simulations highlight primary controls of climate and soil biological respiration, where soil thickness both supplies and limits transport of biologically derived acidity. Consequently, the <span class="hlt">weathering</span> rate maximum occurs at intermediate soil thickness. The value of the maximum <span class="hlt">weathering</span> rate and the precise soil thickness at which it occurs depend on several environmental <span class="hlt">variables</span>, including precipitation regime, soil inundation, vegetation characteristics, and rate of groundwater drainage. Simulations for environmental conditions specific to Big Cypress suggest that wetland depressions in this landscape began to form around beginning of the Holocene with gradual dissolution of limestone bedrock and attendant soil development, highlighting large influence of age-varying soil thickness on <span class="hlt">weathering</span> rates and consequent landscape development. While climatic <span class="hlt">variables</span> are often considered most important for chemical <span class="hlt">weathering</span>, our results indicate that soil thickness and biotic activity are equally important. <span class="hlt">Weathering</span> rates reflect complex interactions among soil thickness, climate, and local hydrologic and biotic processes, which jointly shape the supply and</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/biblio/1439093-ecohydrologic-processes-soil-thickness-feedbacks-control-limestone-weathering-rates-karst-landscape','SCIGOV-STC'); return false;" href="https://www.osti.gov/biblio/1439093-ecohydrologic-processes-soil-thickness-feedbacks-control-limestone-weathering-rates-karst-landscape"><span>Ecohydrologic processes and soil thickness feedbacks control limestone-<span class="hlt">weathering</span> rates in a karst landscape</span></a></p> <p><a target="_blank" href="http://www.osti.gov/search">DOE Office of Scientific and Technical Information (OSTI.GOV)</a></p> <p>Dong, Xiaoli; Cohen, Matthew J.; Martin, Jonathan B.</p> <p></p> <p>Here, chemical <span class="hlt">weathering</span> of bedrock plays an essential role in the formation and evolution of Earth's critical zone. Over geologic time, the negative feedback between temperature and chemical <span class="hlt">weathering</span> rates contributes to the regulation of Earth climate. The challenge of understanding <span class="hlt">weathering</span> rates and the resulting evolution of critical zone structures lies in complicated interactions and feedbacks among environmental <span class="hlt">variables</span>, local ecohydrologic processes, and soil thickness, the relative importance of which remains unresolved. We investigate these interactions using a reactive-transport kinetics model, focusing on a low-relief, wetland-dominated karst landscape (Big Cypress National Preserve, South Florida, USA) as a case study.more » Across a broad range of environmental <span class="hlt">variables</span>, model simulations highlight primary controls of climate and soil biological respiration, where soil thickness both supplies and limits transport of biologically derived acidity. Consequently, the <span class="hlt">weathering</span> rate maximum occurs at intermediate soil thickness. The value of the maximum <span class="hlt">weathering</span> rate and the precise soil thickness at which it occurs depend on several environmental <span class="hlt">variables</span>, including precipitation regime, soil inundation, vegetation characteristics, and rate of groundwater drainage. Simulations for environmental conditions specific to Big Cypress suggest that wetland depressions in this landscape began to form around beginning of the Holocene with gradual dissolution of limestone bedrock and attendant soil development, highlighting large influence of age-varying soil thickness on <span class="hlt">weathering</span> rates and consequent landscape development. While climatic <span class="hlt">variables</span> are often considered most important for chemical <span class="hlt">weathering</span>, our results indicate that soil thickness and biotic activity are equally important. <span class="hlt">Weathering</span> rates reflect complex interactions among soil thickness, climate, and local hydrologic and biotic processes, which jointly shape the supply and</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://cfpub.epa.gov/si/si_public_record_report.cfm?dirEntryId=259169&keyword=temperature+AND+variability&actType=&TIMSType=+&TIMSSubTypeID=&DEID=&epaNumber=&ntisID=&archiveStatus=Both&ombCat=Any&dateBeginCreated=&dateEndCreated=&dateBeginPublishedPresented=&dateEndPublishedPresented=&dateBeginUpdated=&dateEndUpdated=&dateBeginCompleted=&dateEndCompleted=&personID=&role=Any&journalID=&publisherID=&sortBy=revisionDate&count=50','EPA-EIMS'); return false;" href="https://cfpub.epa.gov/si/si_public_record_report.cfm?dirEntryId=259169&keyword=temperature+AND+variability&actType=&TIMSType=+&TIMSSubTypeID=&DEID=&epaNumber=&ntisID=&archiveStatus=Both&ombCat=Any&dateBeginCreated=&dateEndCreated=&dateBeginPublishedPresented=&dateEndPublishedPresented=&dateBeginUpdated=&dateEndUpdated=&dateBeginCompleted=&dateEndCompleted=&personID=&role=Any&journalID=&publisherID=&sortBy=revisionDate&count=50"><span>Pacific Northwest <span class="hlt">tide</span> channel utilization by fish as an ecosystem service - August 2013</span></a></p> <p><a target="_blank" href="http://oaspub.epa.gov/eims/query.page">EPA Science Inventory</a></p> <p></p> <p></p> <p>Background/Question/Methods: Saltwater marsh <span class="hlt">tide</span> channels are considered to be important in the ecology of estuarine fish serving both as a refuge and as a provider of enhanced food resources. However, this presumed function of <span class="hlt">tide</span> channels in Pacific Northwest estuaries has r...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/17550152','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/17550152"><span>Acoustic monitoring of the <span class="hlt">tide</span> height and slope-water intrusion at the New Jersey Shelf in winter conditions.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Turgut, Altan; Orr, Marshall; Pasewark, Bruce</p> <p>2007-05-01</p> <p>Waveguide invariant theory is used to describe the frequency shifts of constant acoustic intensity level curves in broadband signal spectrograms measured at the New Jersey Shelf during the winter of 2003. The broadband signals (270-330 Hz) were transmitted from a fixed source and received at three fixed receivers, located at 10, 20, and 30 km range along a cross-shelf propagation track. The constant acoustic intensity level curves of the received signals indicate regular frequency shifts that can be well predicted by the change in water depth observed through tens of tidal cycles. A second pattern of frequency shifts is observed at only 30 km range where significant <span class="hlt">variability</span> of slope-water intrusion was measured. An excellent agreement between observed frequency shifts of the constant acoustic intensity levels and those predicted by the change in <span class="hlt">tide</span> height and slope water elevations suggests the capability of long-term acoustic monitoring of <span class="hlt">tide</span> and slope water intrusions in winter conditions.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013EGUGA..1512511C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013EGUGA..1512511C"><span><span class="hlt">Weather</span> models as virtual sensors to data-driven rainfall predictions in urban watersheds</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Cozzi, Lorenzo; Galelli, Stefano; Pascal, Samuel Jolivet De Marc; Castelletti, Andrea</p> <p>2013-04-01</p> <p><span class="hlt">Weather</span> and climate predictions are a key element of urban hydrology where they are used to inform water management and assist in flood warning delivering. Indeed, the modelling of the very fast dynamics of urbanized catchments can be substantially improved by the use of <span class="hlt">weather</span>/rainfall predictions. For example, in Singapore Marina Reservoir catchment runoff processes have a very short time of concentration (roughly one hour) and observational data are thus nearly useless for runoff predictions and <span class="hlt">weather</span> prediction are required. Unfortunately, radar nowcasting methods do not allow to carrying out long - term <span class="hlt">weather</span> predictions, whereas numerical models are limited by their coarse spatial scale. Moreover, numerical models are usually poorly reliable because of the fast motion and limited spatial extension of rainfall events. In this study we investigate the combined use of data-driven modelling techniques and <span class="hlt">weather</span> <span class="hlt">variables</span> observed/simulated with a numerical model as a way to improve rainfall prediction accuracy and lead time in the Singapore metropolitan area. To explore the feasibility of the approach, we use a <span class="hlt">Weather</span> Research and Forecast (WRF) model as a virtual sensor network for the input <span class="hlt">variables</span> (the states of the WRF model) to a machine learning rainfall prediction model. More precisely, we combine an input <span class="hlt">variable</span> selection method and a non-parametric tree-based model to characterize the empirical relation between the rainfall measured at the catchment level and all possible <span class="hlt">weather</span> input <span class="hlt">variables</span> provided by WRF model. We explore different lead time to evaluate the model reliability for different long - term predictions, as well as different time lags to see how past information could improve results. Results show that the proposed approach allow a significant improvement of the prediction accuracy of the WRF model on the Singapore urban area.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1997PhDT........85B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1997PhDT........85B"><span>Studies of midlatitude mesospheric temperature <span class="hlt">variability</span> and its relationship to gravity waves, <span class="hlt">tides</span>, and planetary waves</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Beissner, Kenneth C.</p> <p>1997-10-01</p> <p>Temperature observations of the middle atmosphere have been carried out from September 1993 through July 1995 using a Rayleigh backscatter lidar located at Utah State University (42oN, 111oW). Data have been analyzed to obtain absolute temperature profiles from 40 to 90 km. Various sources of error were reviewed in order to ensure the quality of the measurements. This included conducting a detailed examination of the data reduction procedure, integration methods, and averaging techniques, eliminating errors of 1-3%. The temperature structure climatology has been compared with several other mid-latitude data sets, including those from the French lidars, the SME spacecraft, the sodium lidars at Ft. Collins and Urbana, the MSISe90 model, and a high- latitude composite set from Andenes, Norway. In general, good agreement occurs at mid-latitudes, but areas of disagreement do exist. Among these, the Utah temperatures are significantly warmer than the MSISe90 temperatures above approximately 80 km, they are lower below 80 km than any of the others in summer, they show major year- to-year <span class="hlt">variability</span> in the winter profiles, and they differ from the sodium lidar data at the altitudes where the temperature profiles should overlap. Also, comparisons between observations and a physics based global circulation model, the TIME-GCM, were conducted for a mid-latitude site. A photo-chemical model was developed to predict airglow intensity of OH based on output from the TIME-GCM. Many discrepancies between the model and observations were found, including a modeled summer mesopause too high, a stronger summer inversion not normally observed by lidar, a fall-spring asymmetry in the OH winds and lidar temperatures but not reproduced in the TIME-GCM equinoctial periods, larger winter seasonal wind <span class="hlt">tide</span> than observed by the FPI, and a failure of the model to reverse the summertime mesospheric jet. It is our conclusion these discrepancies are due to a gravity wave parameterization in the</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://eric.ed.gov/?q=environmental+AND+news&pg=4&id=EJ1071630','ERIC'); return false;" href="https://eric.ed.gov/?q=environmental+AND+news&pg=4&id=EJ1071630"><span>Risk in Daily Newspaper Coverage of Red <span class="hlt">Tide</span> Blooms in Southwest Florida</span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Li, Zongchao; Garrison, Bruce; Ullmann, Steven G.; Kirkpatrick, Barbara; Fleming, Lora E.; Hoagland, Porter</p> <p>2015-01-01</p> <p>This study investigated newspaper coverage of Florida red <span class="hlt">tide</span> blooms in four metropolitan areas of Southwest Florida during a 25-year period, 1987-2012. We focused on how journalists framed red <span class="hlt">tide</span> stories with respect to environmental risk, health risk, and economic risk. We determined risk to be a key factor in this news coverage, being an…</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012A%26A...544A.132R','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012A%26A...544A.132R"><span>The equilibrium <span class="hlt">tide</span> in stars and giant planets. I. The coplanar case</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Remus, F.; Mathis, S.; Zahn, J.-P.</p> <p>2012-08-01</p> <p>Context. Since 1995, more than 500 extrasolar planets have been discovered orbiting very close to their parent star, where they experience strong tidal interactions. Their orbital evolution depends on the physical mechanisms that cause tidal dissipation, which remain poorly understood. Aims: We refine the theory of the equilibrium <span class="hlt">tide</span> in fluid bodies that are partly or entirely convective, to predict the dynamical evolution of the systems. In particular, we examine the validity of modeling the tidal dissipation using the quality factor Q, which is commonly done. We consider here the simplest case where the considered star or planet rotates uniformly, all spins are aligned, and the companion is reduced to a point mass. Methods: We expand the tidal potential as a Fourier series, and express the hydrodynamical equations in the reference frame, which rotates with the corresponding Fourier component. The results are cast in the form of a complex disturbing function, which may be implemented directly in the equations governing the dynamical evolution of the system. Results: The first manifestation of the <span class="hlt">tide</span> is to distort the shape of the star or planet adiabatically along the line of centers. This generates the divergence-free velocity field of the adiabatic equilibrium <span class="hlt">tide</span>, which is stationary in the frame rotating with the considered Fourier component of the tidal potential; this large-scale velocity field is decoupled from the dynamical <span class="hlt">tide</span>. The tidal kinetic energy is dissipated into heat by means of turbulent friction, which is modeled here as an eddy-viscosity acting on the adiabatic tidal flow. This dissipation induces a second velocity field, the dissipative equilibrium <span class="hlt">tide</span>, which is in quadrature with the exciting potential; this field is responsible for the imaginary part of the disturbing function, which is implemented in the dynamical evolution equations, from which one derives the characteristic evolutionary times. Conclusions: The rate at which the</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ars.usda.gov/research/publications/publication/?seqNo115=303118','TEKTRAN'); return false;" href="http://www.ars.usda.gov/research/publications/publication/?seqNo115=303118"><span>A multi-site stochastic <span class="hlt">weather</span> generator of daily precipitation and temperature</span></a></p> <p><a target="_blank" href="https://www.ars.usda.gov/research/publications/find-a-publication/">USDA-ARS?s Scientific Manuscript database</a></p> <p></p> <p></p> <p>Stochastic <span class="hlt">weather</span> generators are used to generate time series of climate <span class="hlt">variables</span> that have statistical properties similar to those of observed data. Most stochastic <span class="hlt">weather</span> generators work for a single site, and can only generate climate data at a single point, or independent time series at sever...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018BGeo...15..997W','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018BGeo...15..997W"><span>Tidal <span class="hlt">variability</span> of nutrients in a coastal coral reef system influenced by groundwater</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Wang, Guizhi; Wang, Shuling; Wang, Zhangyong; Jing, Wenping; Xu, Yi; Zhang, Zhouling; Tan, Ehui; Dai, Minhan</p> <p>2018-02-01</p> <p>.76), respectively. This similarity indicates that the composition of nutrients in the water column of the reef system was closely related with biological processes during both tidal periods, but the biological influence appeared to be less dominant, as inferred from the less significant correlations (R2 = 0.16) during the spring <span class="hlt">tide</span> when groundwater discharge was more prominent. Thus, the <span class="hlt">variability</span> of nutrients in the coral reef system was regulated mainly by biological uptake and release in a spring-neap <span class="hlt">tide</span> and impacted by mixing of tidally driven groundwater and offshore seawater during spring <span class="hlt">tide</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/servlets/purl/6512366','SCIGOV-STC'); return false;" href="https://www.osti.gov/servlets/purl/6512366"><span><span class="hlt">Weather</span> data for simplified energy calculation methods. Volume IV. United States: WYEC data</span></a></p> <p><a target="_blank" href="http://www.osti.gov/search">DOE Office of Scientific and Technical Information (OSTI.GOV)</a></p> <p>Olsen, A.R.; Moreno, S.; Deringer, J.</p> <p></p> <p>The objective of this report is to provide a source of <span class="hlt">weather</span> data for direct use with a number of simplified energy calculation methods available today. Complete <span class="hlt">weather</span> data for a number of cities in the United States are provided for use in the following methods: degree hour, modified degree hour, bin, modified bin, and <span class="hlt">variable</span> degree day. This report contains sets of <span class="hlt">weather</span> data for 23 cities using <span class="hlt">Weather</span> Year for Energy Calculations (WYEC) source <span class="hlt">weather</span> data. Considerable overlap is present in cities (21) covered by both the TRY and WYEC data. The <span class="hlt">weather</span> data at each city hasmore » been summarized in a number of ways to provide differing levels of detail necessary for alternative simplified energy calculation methods. <span class="hlt">Weather</span> <span class="hlt">variables</span> summarized include dry bulb and wet bulb temperature, percent relative humidity, humidity ratio, wind speed, percent possible sunshine, percent diffuse solar radiation, total solar radiation on horizontal and vertical surfaces, and solar heat gain through standard DSA glass. Monthly and annual summaries, in some cases by time of day, are available. These summaries are produced in a series of nine computer generated tables.« less</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016EGUGA..1811787G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016EGUGA..1811787G"><span>Assessment of rock mechanical properties and seismic slope stability in <span class="hlt">variably</span> <span class="hlt">weathered</span> layered basalts</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Greenwood, William; Clark, Marin; Zekkos, Dimitrios; Von Voigtlander, Jennifer; Bateman, Julie; Lowe, Katherine; Hirose, Mitsuhito; Anderson, Suzanne; Anderson, Robert; Lynch, Jerome</p> <p>2016-04-01</p> <p>A field and laboratory experimental study was conducted to assess the influence of <span class="hlt">weathering</span> on the mechanical properties of basalts in the region of the Kohala volcano on the island of Hawaii. Through the systematic characterization of the <span class="hlt">weathering</span> profiles developed in different precipitation regimes, we aim to explain the regional pattern of stability of slopes in layered basalts that were observed during the 2006 Mw 6.7 Kiholo Bay earthquake. While deeper <span class="hlt">weathering</span> profiles on the wet side of the island might be expected to promote more and larger landslides, the distribution of landslides during the Kiholo Bay earthquake did not follow this anticipated trend. Landslide frequency (defined as number of landslides divided by total area) was similar on the steepest slopes (> 50-60) for both the dry and the wet side of the study area suggesting relatively strong ground materials irrespective of <span class="hlt">weathering</span>. The study location is ideally suited to investigate the role of precipitation, and more broadly of climate, on the mechanical properties of the local rock units because the presence of the Kohala volcano produces a significant precipitation gradient on what are essentially identical basaltic flows. Mean annual precipitation (MAP) varies by more than an order of magnitude, from 200 mm/year on the western side of the volcano to 4000 mm/year in the eastern side. We will present results of measured shear wave velocities using a seismic surface wave methodology. These results were paired with laboratory testing on selected basalt specimens that document the sample-scale shear wave velocity and unconfined compressive strength of the basaltic rocks. Shear wave velocity and unconfined strength of the rocks are correlated and are both significantly lower in <span class="hlt">weathered</span> rocks near the ground surface than at depth. This <span class="hlt">weathering</span>-related reduction in shear wave velocity extends to greater depths in areas of high precipitation compared to areas of lower precipitation</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2010EGUGA..12.2525S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2010EGUGA..12.2525S"><span>A Synoptic <span class="hlt">Weather</span> Typing Approach and Its application to Assess Climate Change Impacts on Extreme <span class="hlt">Weather</span> Events at Local Scale in South-Central Canada</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Shouquan Cheng, Chad; Li, Qian; Li, Guilong</p> <p>2010-05-01</p> <p>The synoptic <span class="hlt">weather</span> typing approach has become popular in evaluating the impacts of climate change on a variety of environmental problems. One of the reasons is its ability to categorize a complex set of meteorological <span class="hlt">variables</span> as a coherent index, which can facilitate analyses of local climate change impacts. The <span class="hlt">weather</span> typing method has been successfully applied in Environment Canada for several research projects to analyze climatic change impacts on a number of extreme <span class="hlt">weather</span> events, such as freezing rain, heavy rainfall, high-/low-flow events, air pollution, and human health. These studies comprise of three major parts: (1) historical simulation modeling to verify the extreme <span class="hlt">weather</span> events, (2) statistical downscaling to provide station-scale future hourly/daily climate data, and (3) projections of changes in frequency and intensity of future extreme <span class="hlt">weather</span> events in this century. To achieve these goals, in addition to synoptic <span class="hlt">weather</span> typing, the modeling conceptualizations in meteorology and hydrology and a number of linear/nonlinear regression techniques were applied. Furthermore, a formal model result verification process has been built into each of the three parts of the projects. The results of the verification, based on historical observations of the outcome <span class="hlt">variables</span> predicted by the models, showed very good agreement. The modeled results from these projects found that the frequency and intensity of future extreme <span class="hlt">weather</span> events are projected to significantly increase under a changing climate in this century. This talk will introduce these research projects and outline the modeling exercise and result verification process. The major findings on future projections from the studies will be summarized in the presentation as well. One of the major conclusions from the studies is that the procedures (including synoptic <span class="hlt">weather</span> typing) used in the studies are useful for climate change impact analysis on future extreme <span class="hlt">weather</span> events. The implication of</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li><a href="#" onclick='return showDiv("page_23");'>23</a></li> <li class="active"><span>24</span></li> <li><a href="#" onclick='return showDiv("page_25");'>25</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_24 --> <div id="page_25" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li><a href="#" onclick='return showDiv("page_23");'>23</a></li> <li><a href="#" onclick='return showDiv("page_24");'>24</a></li> <li class="active"><span>25</span></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="481"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015JGRC..120.6865L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015JGRC..120.6865L"><span>Impacts of <span class="hlt">tides</span> on tsunami propagation due to potential Nankai Trough earthquakes in the Seto Inland Sea, Japan</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Lee, Han Soo; Shimoyama, Tomohisa; Popinet, Stéphane</p> <p>2015-10-01</p> <p>The impacts of <span class="hlt">tides</span> on extreme tsunami propagation due to potential Nankai Trough earthquakes in the Seto Inland Sea (SIS), Japan, are investigated through numerical experiments. Tsunami experiments are conducted based on five scenarios that consider <span class="hlt">tides</span> at four different phases, such as flood, high, ebb, and low <span class="hlt">tides</span>. The probes that were selected arbitrarily in the Bungo and Kii Channels show less significant effects of <span class="hlt">tides</span> on tsunami heights and the arrival times of the first waves than those that experience large tidal ranges in inner basins and bays of the SIS. For instance, the maximum tsunami height and the arrival time at Toyomaesi differ by more than 0.5 m and nearly 1 h, respectively, depending on the tidal phase. The uncertainties defined in terms of calculated maximum tsunami heights due to <span class="hlt">tides</span> illustrate that the calculated maximum tsunami heights in the inner SIS with standing <span class="hlt">tides</span> have much larger uncertainties than those of two channels with propagating <span class="hlt">tides</span>. Particularly in Harima Nada, the uncertainties due to the impacts of <span class="hlt">tides</span> are greater than 50% of the tsunami heights without tidal interaction. The results recommend simulate tsunamis together with <span class="hlt">tides</span> in shallow water environments to reduce the uncertainties involved with tsunami modeling and predictions for tsunami hazards preparedness. This article was corrected on 26 OCT 2015. See the end of the full text for details.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018AAS...23230303H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018AAS...23230303H"><span>Optimized Strategies for Detecting Extrasolar Space <span class="hlt">Weather</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Hallinan, Gregg</p> <p>2018-06-01</p> <p>Fully understanding the implications of space <span class="hlt">weather</span> for the young solar system, as well as the wider population of planet-hosting stars, requires remote sensing of space <span class="hlt">weather</span> in other stellar systems. Solar coronal mass ejections can be accompanied by bright radio bursts at low frequencies (typically <100 MHz), that are produced as the resulting shockwave propagates through the corona and interplanetary medium.; searches for similar emissions are ongoing from nearby stellar systems. Exoplanets that encounter CMEs can increase in radio luminosity by orders of magnitude at kHz-MHz frequencies. A detection of this radio emission allows the direct measurement of the magnetic field strength of the planet, informing on whether the atmosphere of the planet can survive the intense magnetic activity of its host star. However, both stellar and planetary radio emission are highly <span class="hlt">variable</span> and optimal strategies for detection of these emissions requires the capability to monitor 1000s of nearby stellar/planetary systems simultaneously. I will discuss optimized strategies for both ground and space-based experiments to take advantage of the highly <span class="hlt">variable</span> nature of the radio emissions powered by extrasolar space <span class="hlt">weather</span> to enable detection of stellar CMEs and planetary magnetospheres.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015IJAsB..14..233C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015IJAsB..14..233C"><span>Spin evolution of Earth-sized exoplanets, including atmospheric <span class="hlt">tides</span> and core-mantle friction</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Cunha, Diana; Correia, Alexandre C. M.; Laskar, Jacques</p> <p>2015-04-01</p> <p>Planets with masses between 0.1 and 10 M ⊕ are believed to host dense atmospheres. These atmospheres can play an important role on the planet's spin evolution, since thermal atmospheric <span class="hlt">tides</span>, driven by the host star, may counterbalance gravitational <span class="hlt">tides</span>. In this work, we study the long-term spin evolution of Earth-sized exoplanets. We generalize previous works by including the effect of eccentric orbits and obliquity. We show that under the effect of <span class="hlt">tides</span> and core-mantle friction, the obliquity of the planets evolves either to 0° or 180°. The rotation of these planets is also expected to evolve into a very restricted number of equilibrium configurations. In general, none of these equilibria is synchronous with the orbital mean motion. The role of thermal atmospheric <span class="hlt">tides</span> becomes more important for Earth-sized planets in the habitable zones of their systems; so they cannot be neglected when we search for their potential habitability.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2007AGUSM.A53C..04S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2007AGUSM.A53C..04S"><span>Seasonal <span class="hlt">Variability</span> Study of the Tropospheric Zenithal Delay in the South America using regional Numerical <span class="hlt">Weather</span> Prediction model</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Sapucci, L. F.; Monico, J. G.; Machado, L. T.</p> <p>2007-05-01</p> <p>In 2010 a new navigation and administration system of the air traffic, denominated CNS-ATM (Communication Navigation Surveillance - Air Traffic Management) should be running operationally in South America. This new system will basically employ the positioning techniques by satellites to the management and air traffic control. However, the efficiency of this new system demands the knowledge of the behavior of the atmosphere, consequently, an appropriated Zenithal Tropospheric Delay (ZTD) modeling in a regional scale. The predictions of ZTD values from Numeric <span class="hlt">Weather</span> Prediction (NWP), denominated here dynamic modeling, is an alternative to model the atmospheric gases effects in the radio-frequency signals in real time. Brazilian Center for <span class="hlt">Weather</span> Forecasting and Climate Studies (CPTEC) of the National Institute for Space Research (INPE), jointly with researchers from UNESP (Sao Paulo State University), has generated operationally prediction of ZTD values to South America Continent (available in the electronic address http:satelite.cptec.inpe.br/htmldocs/ztd/zenithal.htm). The available regional version is obtained using ETA model (NWP model with horizontal resolution of 20 km and 42 levels in the vertical). The application of NWP permit assess the temporal and spatial variation of ZTD values, which is an important characteristic of this techniques. The aim of the present paper is to investigate the ZTD seasonal <span class="hlt">variability</span> over South America continent. A <span class="hlt">variability</span> analysis of the ZTD components [hydrostatic(ZHD) and wet(ZWD)] is also presented, as such as discussion of main factors that influence this variation in this region. The hydrostatic component variation is related with atmospheric pressure oscillation, which is influenced by relief and high pressure centers that prevail over different region of the South America continent. The wet component oscillation is due to the temperature and humidity <span class="hlt">variability</span>, which is also influenced by relief and by synoptic</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=GL-2002-002467&hterms=wine&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D70%26Ntt%3Dwine','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=GL-2002-002467&hterms=wine&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D70%26Ntt%3Dwine"><span>Red <span class="hlt">Tide</span> Strands South African Rock Lobsters</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p></p> <p>2002-01-01</p> <p>Although some red <span class="hlt">tides</span> form a healthy part of phytoplankton production, recurrent harmful or toxic blooms also occur, with results depending upon the type of plankton and on atmospheric and oceanic conditions. At Elands Bay in South Africa's Western Cape province, about 1000 tons of rock lobsters beached themselves during February 2002, when the decay of dense blooms of phytoplankton caused a rapid reduction in the oxygen concentration of nearshore waters. The lobsters (or crayfish, as they are known locally) moved toward the breaking surf in search of oxygen, but were stranded by the retreating <span class="hlt">tide</span>. The Multi-angle Imaging SpectroRadiometer's nadir camera acquired these red, green, blue composites on February 2 and 18, 2002, during Terra orbits 11315 and 11548. The colors have been accentuated to highlight the bloom, and land and water have been enhanced separately. The two views show the shoreward migration of the algal bloom. Each image represents an area of about 205 kilometers x 330 kilometers. Elands Bay is situated near the mouth of the Doring River, about 75 kilometers northeast of the jutting Cape Columbine. The term 'red <span class="hlt">tide</span>' is used to refer to a number of different types of phytoplankton blooms of various hues. The wine color of certain parts of this bloom are consistent with the ciliate species Mesodinium rubrum, which has been associated with recurring harmful algal blooms along the Western Cape coast. Under these conditions, the lobsters are not poisoned. During the recent event, government and military staff transported as many of the living lobsters as possible to areas that were less affected by the red <span class="hlt">tide</span>. At the same time, people came from across South Africa to gather the undersized creatures for food. The effects of the losses on the maritime economy are expected to be felt over the next few years. MISR was built and is managed by NASA's Jet Propulsion Laboratory, Pasadena, CA, for NASA's Office of Earth Science, Washington, DC. The Terra</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=PIA03447&hterms=wine&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D70%26Ntt%3Dwine','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=PIA03447&hterms=wine&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D70%26Ntt%3Dwine"><span>Red <span class="hlt">Tide</span> Strands South African Rock Lobsters</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p></p> <p>2002-01-01</p> <p><p/>Although some red <span class="hlt">tides</span> form a healthy part of phytoplankton production, recurrent harmful or toxic blooms also occur, with results depending upon the type of plankton and on atmospheric and oceanic conditions. At Elands Bay in South Africa's Western Cape province, about 1000 tons of rock lobsters beached themselves during February 2002, when the decay of dense blooms of phytoplankton caused a rapid reduction in the oxygen concentration of nearshore waters. The lobsters (or crayfish, as they are known locally) moved toward the breaking surf in search of oxygen, but were stranded by the retreating <span class="hlt">tide</span>.<p/>The Multi-angle Imaging SpectroRadiometer's nadir camera acquired these red, green, blue composites on February 2 and 18, 2002, during Terra orbits 11315 and 11548. The colors have been accentuated to highlight the bloom, and land and water have been enhanced separately. The two views show the shoreward migration of the algal bloom. Each image represents an area of about 205 kilometers x 330 kilometers. Elands Bay is situated near the mouth of the Doring River, about 75 kilometers northeast of the jutting Cape Columbine.<p/>The term 'red <span class="hlt">tide</span>' is used to refer to a number of different types of phytoplankton blooms of various hues. The wine color of certain parts of this bloom are consistent with the ciliate species Mesodinium rubrum, which has been associated with recurring harmful algal blooms along the Western Cape coast. Under these conditions, the lobsters are not poisoned. During the recent event, government and military staff transported as many of the living lobsters as possible to areas that were less affected by the red <span class="hlt">tide</span>. At the same time, people came from across South Africa to gather the undersized creatures for food. The effects of the losses on the maritime economy are expected to be felt over the next few years.<p/>MISR was built and is managed by NASA's Jet Propulsion Laboratory, Pasadena, CA, for NASA's Office of Earth Science, Washington</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=187590','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=187590"><span>How do People Solve the “<span class="hlt">Weather</span> Prediction” Task?: Individual <span class="hlt">Variability</span> in Strategies for Probabilistic Category Learning</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Gluck, Mark A.; Shohamy, Daphna; Myers, Catherine</p> <p>2002-01-01</p> <p>Probabilistic category learning is often assumed to be an incrementally learned cognitive skill, dependent on nondeclarative memory systems. One paradigm in particular, the <span class="hlt">weather</span> prediction task, has been used in over half a dozen neuropsychological and neuroimaging studies to date. Because of the growing interest in using this task and others like it as behavioral tools for studying the cognitive neuroscience of cognitive skill learning, it becomes especially important to understand how subjects solve this kind of task and whether all subjects learn it in the same way. We present here new experimental and theoretical analyses of the <span class="hlt">weather</span> prediction task that indicate that there are at least three different strategies that describe how subjects learn this task. (1) An optimal multi-cue strategy, in which they respond to each pattern on the basis of associations of all four cues with each outcome; (2) a one-cue strategy, in which they respond on the basis of presence or absence of a single cue, disregarding all other cues; or (3) a singleton strategy, in which they learn only about the four patterns that have only one cue present and all others absent. This <span class="hlt">variability</span> in how subjects approach this task may have important implications for interpreting how different brain regions are involved in probabilistic category learning. PMID:12464701</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.er.usgs.gov/publication/70154952','USGSPUBS'); return false;" href="https://pubs.er.usgs.gov/publication/70154952"><span>Impacts of <span class="hlt">weather</span> on long-term patterns of plant richness and diversity vary with location and management</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Jonas, Jayne L.; Buhl, Deborah A.; Symstad, Amy J.</p> <p>2015-01-01</p> <p>Better understanding the influence of precipitation and temperature on plant assemblages is needed to predict the effects of climate change. Many studies have examined the relationship between plant productivity and <span class="hlt">weather</span> (primarily precipitation), but few have directly assessed the relationship between plant richness or diversity and <span class="hlt">weather</span> despite their increased use as metrics of ecosystem condition. We focus on the grasslands of central North America, which are characterized by high temporal climatic <span class="hlt">variability</span>. Over the next 100 years, these grasslands are predicted to experience further increased <span class="hlt">variability</span> in growing season precipitation, as well as increased temperatures, due to global climate change. We assess 1) the portion of interannual <span class="hlt">variability</span> of richness and diversity explained by <span class="hlt">weather</span>, 2) how relationships between these metrics and <span class="hlt">weather</span> vary among plant assemblages, and 3) which aspects of <span class="hlt">weather</span> best explain temporal <span class="hlt">variability</span>. We used an information-theoretic approach to assess relationships between long-term plant richness and diversity patterns and a priori <span class="hlt">weather</span> covariates using six datasets from four grasslands. <span class="hlt">Weather</span> explained up to 49% and 63% of interannual <span class="hlt">variability</span> in total plant species richness and diversity, respectively. However, richness and diversity responses to specific <span class="hlt">weather</span> <span class="hlt">variables</span> varied both among sites and among experimental treatments within sites. In general, we found many instances in which temperature was of equal or greater importance as precipitation, as well as evidence of the importance of lagged effects and precipitation or temperature <span class="hlt">variability</span>. Although precipitation has been shown to be a key driver of productivity in grasslands, our results indicate that increasing temperatures alone, without substantial changes in precipitation patterns, could have measurable effects on Great Plains grassland plant assemblages and biodiversity metrics. Our results also suggest that richness and</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2005IJBm...49..238B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2005IJBm...49..238B"><span>Panic anxiety, under the <span class="hlt">weather</span>?</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Bulbena, A.; Pailhez, G.; Aceña, R.; Cunillera, J.; Rius, A.; Garcia-Ribera, C.; Gutiérrez, J.; Rojo, C.</p> <p>2005-03-01</p> <p>The relationship between <span class="hlt">weather</span> conditions and psychiatric disorders has been a continuous subject of speculation due to contradictory findings. This study attempts to further clarify this relationship by focussing on specific conditions such as panic attacks and non-panic anxiety in relation to specific meteorological <span class="hlt">variables</span>. All psychiatric emergencies attended at a general hospital in Barcelona (Spain) during 2002 with anxiety as main complaint were classified as panic or non-panic anxiety according to strict independent and retrospective criteria. Both groups were assessed and compared with meteorological data (wind speed and direction, daily rainfall, temperature, humidity and solar radiation). Seasons and weekend days were also included as independent <span class="hlt">variables</span>. Non-parametric statistics were used throughout since most <span class="hlt">variables</span> do not follow a normal distribution. Logistic regression models were applied to predict days with and without the clinical condition. Episodes of panic were three times more common with the poniente wind (hot wind), twice less often with rainfall, and one and a half times more common in autumn than in other seasons. These three trends (hot wind, rainfall and autumn) were accumulative for panic episodes in a logistic regression formula. Significant reduction of episodes on weekends was found only for non-panic episodes. Panic attacks, unlike other anxiety episodes, in a psychiatric emergency department in Barcelona seem to show significant meteorotropism. Assessing specific disorders instead of overall emergencies or other <span class="hlt">variables</span> of a more general quality could shed new light on the relationship between <span class="hlt">weather</span> conditions and behaviour.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2010JGRD..11518112F','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2010JGRD..11518112F"><span>Southern Argentina Agile Meteor Radar: System design and initial measurements of large-scale winds and <span class="hlt">tides</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Fritts, D. C.; Janches, D.; Iimura, H.; Hocking, W. K.; Mitchell, N. J.; Stockwell, R. G.; Fuller, B.; Vandepeer, B.; Hormaechea, J.; Brunini, C.; Levato, H.</p> <p>2010-09-01</p> <p>The Southern Argentina Agile Meteor Radar (SAAMER) was installed at Rio Grande on Tierra del Fuego (53.8°S, 67.8°W) in May 2008 and has been operational for ˜24 months. This paper describes the motivations for the radar design and its placement at the southern tip of South America, its operating modes and capabilities, and observations of the mean winds, planetary waves, and <span class="hlt">tides</span> during its first ˜20 months of operation. SAAMER was specifically designed to provide very high resolution of large-scale motions and hopefully enable direct measurements of the vertical momentum flux by gravity waves, which have only been possible previously with dual- or multiple-beam radars and lidars or in situ measurements. SAAMER was placed on Tierra del Fuego because it was a region devoid of similar measurements, the latitude was anticipated to provide high sensitivity to an expected large semidiurnal <span class="hlt">tide</span>, and the region is now recognized to be a "hot spot" of small-scale gravity wave activity extending from the troposphere into the mesosphere and lower thermosphere, perhaps the most dynamically active location on Earth. SAAMER was also intended to permit simultaneous enhanced meteor studies, including "head echo" and "nonspecular" measurements, which were previously possible only with high-power large-aperture radars. Initial measurements have defined the mean circulation and structure, exhibited planetary waves at various periods, and revealed large semidiurnal <span class="hlt">tide</span> amplitudes and <span class="hlt">variability</span>, with maximum amplitudes at higher altitudes often exceeding 60 m s-1 and amplitude modulations at periods from a few to ˜30 days.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/biblio/1406799-aerosols-impact-radiation-clouds-precipitation-severe-weather-events','SCIGOV-STC'); return false;" href="https://www.osti.gov/biblio/1406799-aerosols-impact-radiation-clouds-precipitation-severe-weather-events"><span>Aerosols and their Impact on Radiation, Clouds, Precipitation & Severe <span class="hlt">Weather</span> Events</span></a></p> <p><a target="_blank" href="http://www.osti.gov/search">DOE Office of Scientific and Technical Information (OSTI.GOV)</a></p> <p>Li, Zhanqing; Rosenfeld, Daniel; Fan, Jiwen</p> <p></p> <p>Aerosols, the tiny particles suspended in the atmosphere, have been in the forefront of environmental and climate change sciences as the primary atmospheric pollutant and external force affecting Earth’s <span class="hlt">weather</span> and climate. There are two dominant mechanisms by which aerosols affect <span class="hlt">weather</span> and climate: aerosol-radiation interactions (ARI) and aerosol-cloud interactions (ACI). ARI arises from aerosol scattering and absorption, which alters the radiation budgets of the atmosphere and surface, while ACI is rooted to the fact that aerosols serve as cloud condensation nuclei and ice nuclei. Both ARI and ACI are coupled with atmospheric dynamics to produce a chain of complexmore » interactions with a large range of meteorological <span class="hlt">variables</span> that influence both <span class="hlt">weather</span> and climate. Elaborated here are the impacts of aerosols on the radiation budget, clouds (microphysics, structure, and lifetime), precipitation, and severe <span class="hlt">weather</span> events (lightning, thunderstorms, hail, and tornados). Depending on environmental <span class="hlt">variables</span> and aerosol properties, the effects can be both positive and negative, posing the largest uncertainties in the external forcing of the climate system. This has considerably hindered our ability in projecting future climate changes and in doing accurate numerical <span class="hlt">weather</span> predictions.« less</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.sdstate.edu/nrm/organizations/gpnss/tpn/upload/Roche-paper-76-87.pdf','USGSPUBS'); return false;" href="https://www.sdstate.edu/nrm/organizations/gpnss/tpn/upload/Roche-paper-76-87.pdf"><span>The effect of <span class="hlt">weather</span> on morphometric traits of juvenile cliff swallows</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Roche, Erin A.; Brown, Mary Bomberger; Brown, Charles R.</p> <p>2015-01-01</p> <p>Episodes of food deprivation may change how nestling birds allocate energy to the growth of skeletal and feather morphological traits during development. Cliff swallows (Petrochelidon pyrrhonota) are colonial, insectivorous birds that regularly experience brief periods of severe <span class="hlt">weather</span>-induced food deprivation during the nesting season which may affect offspring development. We investigated how annual variation in timing of rearing and <span class="hlt">weather</span> were associated with length of wing and tail, skeletal traits, and body mass in juvenile cliff swallows reared in southwestern Nebraska during 2001–2006. As predicted under conditions of food deprivation, nestling skeletal and feather measurements were generally smaller in cooler years. However, <span class="hlt">variability</span> explained by <span class="hlt">weather</span> was small, suggesting that morphometric traits of juvenile cliff swallows were not highly sensitive to <span class="hlt">weather</span> conditions experienced during this study. Measurements of juvenile morphological traits were positively correlated with measurements taken as adults, meaning that any variation among juveniles in response to rearing conditions showed evidence of persisting into a bird’s first breeding season. Our results show that body size in this species is phenotypically plastic and influenced, in part, by <span class="hlt">weather</span> <span class="hlt">variables</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016AGUOSPO24E3018C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016AGUOSPO24E3018C"><span>Near-surface energy transfers from internal <span class="hlt">tide</span> beams to smaller vertical scale motions</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Chou, S.; Staquet, C.; Carter, G. S.; Luther, D. S.</p> <p>2016-02-01</p> <p>Mechanical energy capable of causing diapycnal mixing in the ocean is transferred to the internal wave field when barotropic <span class="hlt">tides</span> pass over underwater topography and generate internal <span class="hlt">tides</span>. The resulting internal <span class="hlt">tide</span> energy is confined in vertically limited structures, or beams. As internal <span class="hlt">tide</span> beams (ITBs) propagate through regions of non-uniform stratification in the upper ocean, wave energy can be scattered through multiple reflections and refractions, be vertically trapped, or transferred to non-tidal frequencies through different nonlinear processes. Various observations have shown that ITBs are no longer detectable in horizontal kinetic energy beyond the first surface reflection. Importantly, this implies that some of the internal <span class="hlt">tide</span> energy no longer propagates in to the abyssal ocean and consequently will not be available to maintain the density stratification. Using the NHM, a nonlinear and nonhydrostatic model based on the MITgcm, simulations of an ITB propagating up to the sea surface are examined in order to quantify the transformation of ITB energy to other motions. We compare and contrast the transformations enabled by idealized, smoothly-varying stratification with transformations enabled by realistic stratification containing a broad-band vertical wavenumber spectrum of variations. Preliminary two-dimensional results show that scattering due to small-scale structure in realistic stratification profiles from Hawaii can lead to energy being vertically trapped near the surface. Idealized simulations of "locally" generated internal solitary waves are analyzed in terms of energy flux transfers from the ITB to solitary waves, higher harmonics, and mean flow. The amount of internal <span class="hlt">tide</span> energy which propagates back down after near-surface reflection of the ITB in different environments is quantified.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://eric.ed.gov/?q=Physical+AND+science+AND+textbook&pg=4&id=EJ1083305','ERIC'); return false;" href="https://eric.ed.gov/?q=Physical+AND+science+AND+textbook&pg=4&id=EJ1083305"><span>Using <span class="hlt">Tide</span> Data in Introductory Classes</span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>De Jong, Marvin L.</p> <p>2006-01-01</p> <p>Oceantides are not typically high in our consciousness here in Missouri, but in teaching astronomy and physical science the subject always comes up, and teachers of physical science and astronomy are all quite familiar with the textbook explanations. Our goal here is not to explain <span class="hlt">tides</span> but to make some suggestions about how, on their own,…</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/17361736','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/17361736"><span>[Research on airborne hyperspectral identification of red <span class="hlt">tide</span> organism dominant species based on SVM].</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Ma, Yi; Zhang, Jie; Cui, Ting-wei</p> <p>2006-12-01</p> <p>Airborne hyperspectral identification of red <span class="hlt">tide</span> organism dominant species can provide technique for distinguishing red <span class="hlt">tide</span> and its toxin, and provide support for scaling the disaster. Based on support vector machine(SVM), the present paper provides an identification model of red <span class="hlt">tide</span> dominant species. Utilizing this model, the authors accomplished three identification experiments with the hyperspectral data obtained on 16th July, and 19th and 25th August, 2001. It is shown from the identification results that the model has a high precision and is not restricted by high dimension of the hyperspectral data.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/25972565','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/25972565"><span>Environmental Chemistry and Chemical Ecology of "Green <span class="hlt">Tide</span>" Seaweed Blooms.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Van Alstyne, Kathryn L; Nelson, Timothy A; Ridgway, Richard L</p> <p>2015-09-01</p> <p>Green <span class="hlt">tides</span> are large growths or accumulations of green seaweeds that have been increasing in magnitude and frequency around the world. Because green <span class="hlt">tides</span> consist of vast biomasses of algae in a limited area and are often seasonal or episodic, they go through periods of rapid growth in which they take up large amounts of nutrients and dissolved gases and generate bioactive natural products that may be stored in the plants, released into the environment, or broken down during decomposition. As a result of the use and production of inorganic and organic compounds, the algae in these blooms can have detrimental impacts on other organisms. Here, we review some of the effects that green <span class="hlt">tides</span> have on the chemistry of seawater and the effects of the natural products that they produce. As blooms are developing and expanding, algae in green <span class="hlt">tides</span> take up inorganic nutrients, such as nitrate and ortho-phosphate, which can limit their availability to other photosynthetic organisms. Their uptake of dissolved inorganic carbon for use in photosynthesis can cause localized spikes in the pH of seawater during the day with concomitant drops in the pH at night when the algae are respiring. Many of the algae that form green-<span class="hlt">tide</span> blooms produce allelopathic compounds, which are metabolites that affect other species. The best documented allelopathic compounds include dimethylsulfoniopropionate (DMSP), dopamine, and reactive oxygen species (ROS) and their breakdown products. DMSP and dopamine are involved in defenses against herbivores. Dopamine and ROS are released into seawater where they can be allelopathic or toxic to other organisms. Thus, these macroalgal blooms can have harmful effects on nearby organisms by altering concentrations of nutrients and dissolved gas in seawater and by producing and releasing allelopathic or toxic compounds. © The Author 2015. Published by Oxford University Press on behalf of the Society for Integrative and Comparative Biology. All rights reserved</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.er.usgs.gov/publication/28633','USGSPUBS'); return false;" href="https://pubs.er.usgs.gov/publication/28633"><span>A conceptual <span class="hlt">weather</span>-type classification procedure for the Philadelphia, Pennsylvania, area</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>McCabe, Gregory J.</p> <p>1990-01-01</p> <p>A simple method of <span class="hlt">weather</span>-type classification, based on a conceptual model of pressure systems that pass through the Philadelphia, Pennsylvania, area, has been developed. The only inputs required for the procedure are daily mean wind direction and cloud cover, which are used to index the relative position of pressure systems and fronts to Philadelphia.Daily mean wind-direction and cloud-cover data recorded at Philadelphia, Pennsylvania, from January 1954 through August 1988 were used to categorize daily <span class="hlt">weather</span> conditions. The conceptual <span class="hlt">weather</span> types reflect changes in daily air and dew-point temperatures, and changes in monthly mean temperature and monthly and annual precipitation. The <span class="hlt">weather</span>-type classification produced by using the conceptual model was similar to a classification produced by using a multivariate statistical classification procedure. Even though the conceptual <span class="hlt">weather</span> types are derived from a small amount of data, they appear to account for the <span class="hlt">variability</span> of daily <span class="hlt">weather</span> patterns sufficiently to describe distinct <span class="hlt">weather</span> conditions for use in environmental analyses of <span class="hlt">weather</span>-sensitive processes.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017AGUFMPA53C..06W','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017AGUFMPA53C..06W"><span>Using Music to Communicate <span class="hlt">Weather</span> and Climate</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Williams, P.; Aplin, K. L.; Brown, S.</p> <p>2017-12-01</p> <p>Depictions of <span class="hlt">weather</span> and other atmospheric phenomena are common throughout the arts. Unlike in the visual arts, however, there has been little study of meteorological inspiration in music. This presentation will discuss the frequencies with which different <span class="hlt">weather</span> types have been depicted in music over time, covering the period from the seventeenth century to the present day. Beginning with classical orchestral music, we find that composers were generally influenced by their own country's climate in the type of <span class="hlt">weather</span> they chose to represent. Depictions of <span class="hlt">weather</span> vary from explicit mimicry using traditional and specialized orchestral instruments, through to subtle suggestions. Pieces depicting stormy <span class="hlt">weather</span> tend to be in minor keys, whereas pieces depicting fair <span class="hlt">weather</span> tend to be in major keys. As befits the national stereotype, British composers seem disproportionately keen to depict the UK's <span class="hlt">variable</span> <span class="hlt">weather</span> patterns and stormy coastline. Moving onto modern popular music, we have identified and analyzed over 750 songs referring to different <span class="hlt">weather</span> types. We find that lyrical references to bad <span class="hlt">weather</span> peaked in songs written during the stormy 1950s and 60s, when there were many hurricanes, before declining in the relatively calm 1970s and 80s. This finding again suggests a causal link between song-writers' meteorological environments and compositional outputs. Composers and song-writers have a unique ability to emotionally connect their listeners to the environment. This ability could be exploited to communicate environmental science to a broader audience. Our work provides a catalogue of cultural responses to <span class="hlt">weather</span> before (and during the early stages of) climate change. The effects of global warming may influence musical expression in future, in which case our work will provide a baseline for comparison.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016AGUFMED41B..06W','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016AGUFMED41B..06W"><span>Using Music to Communicate <span class="hlt">Weather</span> and Climate</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Williams, P.; Aplin, K. L.; Brown, S.; Jenkins, K.; Mander, S.; Walsh, C.</p> <p>2016-12-01</p> <p>Depictions of <span class="hlt">weather</span> and other atmospheric phenomena are common throughout the arts. Unlike in the visual arts, however, there has been little study of meteorological inspiration in music. This presentation will discuss the frequencies with which different <span class="hlt">weather</span> types have been depicted in music over time, covering the period from the seventeenth century to the present day. Beginning with classical orchestral music, we find that composers were generally influenced by their own country's climate in the type of <span class="hlt">weather</span> they chose to represent. Depictions of <span class="hlt">weather</span> vary from explicit mimicry using traditional and specialized orchestral instruments, through to subtle suggestions. Pieces depicting stormy <span class="hlt">weather</span> tend to be in minor keys, whereas pieces depicting fair <span class="hlt">weather</span> tend to be in major keys. As befits the national stereotype, British composers seem disproportionately keen to depict the UK's <span class="hlt">variable</span> <span class="hlt">weather</span> patterns and stormy coastline. Moving onto modern popular music, we have identified and analyzed over 750 songs referring to different <span class="hlt">weather</span> types. We find that lyrical references to bad <span class="hlt">weather</span> peaked in songs written during the stormy 1950s and 60s, when there were many hurricanes, before declining in the relatively calm 1970s and 80s. This finding again suggests a causal link between song-writers' meteorological environments and compositional outputs. Composers and song-writers have a unique ability to emotionally connect their listeners to the environment. This ability could be exploited to communicate environmental science to a broader audience. Our work provides a catalogue of cultural responses to <span class="hlt">weather</span> before (and during the early stages of) climate change. The effects of global warming may influence musical expression in future, in which case our work will provide a baseline for comparison.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014DPS....4640504R','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014DPS....4640504R"><span>Linking Europa’s Plume Activity to <span class="hlt">Tides</span>, Tectonics, and Liquid Water</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Rhoden, Alyssa R.; Hurford, Terry; Roth, Lorenz; Retherford, Kurt</p> <p>2014-11-01</p> <p>Much of the geologic activity preserved on Europa’s icy surface has been attributed to tidal deformation, mainly due to Europa’s eccentric orbit. Although the surface is geologically young, evidence of ongoing tidally-driven processes has been lacking. However, a recent observation of water vapor near Europa’s south pole suggests that it may be geologically active. Non-detections in previous and follow-up observations indicate a temporal variation in plume visibility and suggests a relationship to Europa’s tidal cycle. Similarly, the Cassini spacecraft has observed plumes emanating from the south pole of Saturn’s moon, Enceladus, and <span class="hlt">variability</span> in the intensity of eruptions has been linked to its tidal cycle. The inference that a similar mechanism controls plumes at both Europa and Enceladus motivates further analysis of Europa’s plume behavior and the relationship between plumes, <span class="hlt">tides</span>, and liquid water on these two satellites.We determine the locations and orientations of hypothetical tidally-driven fractures that best match the temporal <span class="hlt">variability</span> of the plumes observed at Europa. Specifically, we identify model faults that are in tension at the time in Europa’s orbit when a plume was detected and in compression at times when the plume was not detected. We find that tidal stress driven solely by eccentricity is incompatible with the observations unless additional mechanisms are controlling the eruption timing or restricting the longevity of the plumes. In contrast, the addition of obliquity <span class="hlt">tides</span>, and corresponding precession of the spin pole, can generate a number of model faults that are consistent with the pattern of plume detections. The locations and orientations of the model faults are robust across a broad range of precession rates and spin pole directions. Analysis of the stress variations across model faults suggests that the plumes would be best observed earlier in Europa’s orbit. Our results indicate that Europa’s plumes, if</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li><a href="#" onclick='return showDiv("page_23");'>23</a></li> <li><a href="#" onclick='return showDiv("page_24");'>24</a></li> <li class="active"><span>25</span></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_25 --> <div class="footer-extlink text-muted" style="margin-bottom:1rem; text-align:center;">Some links on this page may take you to non-federal websites. 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