Small scale green infrastructure design to meet different urban hydrological criteria.

PubMed

Jia, Z; Tang, S; Luo, W; Li, S; Zhou, M

2016-04-15

As small scale green infrastructures, rain gardens have been widely advocated for urban stormwater management in the contemporary low impact development (LID) era. This paper presents a simple method that consists of hydrological models and the matching plots of nomographs to provide an informative and practical tool for rain garden sizing and hydrological evaluation. The proposed method considers design storms, infiltration rates and the runoff contribution area ratio of the rain garden, allowing users to size a rain garden for a specific site with hydrological reference and predict overflow of the rain garden under different storms. The nomographs provide a visual presentation on the sensitivity of different design parameters. Subsequent application of the proposed method to a case study conducted in a sub-humid region in China showed that, the method accurately predicted the design storms for the existing rain garden, the predicted overflows under large storm events were within 13-50% of the measured volumes. The results suggest that the nomographs approach is a practical tool for quick selection or assessment of design options that incorporate key hydrological parameters of rain gardens or other infiltration type green infrastructure. The graphic approach as displayed by the nomographs allow urban planners to demonstrate the hydrological effect of small scale green infrastructure and gain more support for promoting low impact development. Copyright © 2016 Elsevier Ltd. All rights reserved.

Rain observations in tropical storm Cora

NASA Technical Reports Server (NTRS)

Wilheit, T. T.; Chang, A. T. C.; King, J. L.; Rodgers, E. B.; Nieman, R. A.; Krupp, B. M.; Siddalingaiah, H.; Diesen, B. C.; Stratigos, J.

1979-01-01

Passive microwave observations were made in tropical storm Cora at 19.35 and 94GHz. These observations suggest that 94GHz is appropriate for mapping the extent of rain over either land or ocean backgrounds and that some rainfall intensity measurement is also possible.

The estimation of convective rainfall by area integrals. I - The theoretical and empirical basis. II - The height-area rainfall threshold (HART) method

NASA Technical Reports Server (NTRS)

Rosenfeld, Daniel; Short, David A.; Atlas, David

1990-01-01

A theory is developed which establishes the basis for the use of rainfall areas within present thresholds as a measure of either the instantaneous areawide rain rate of convective storms or the total volume of rain from an individual storm over its lifetime. The method is based upon the existence of a well-behaved pdf of rain rate either from the many storms at one instant or from a single storm during its life. The generality of the instantaneous areawide method was examined by applying it to quantitative radar data sets from the GARP Tropical Atlantic Experiment for South Africa, Texas, and Darwin (Australia). It is shown that the pdf's developed for each of these areas are consistent with the theory.

STORM WATER BEST MANAGEMENT PRACTICES: CAPACITIES, CAPABILITIES, AND SOME LIMITATIONS

EPA Science Inventory

This presentation will cover the basics of what a storm water best management practices and focus on infiltration-type practices using the example of rain gardens. I will demonstrate how water moves through rain gardens with a simple hydrologic model and discuss ancillary benefit...

Studies of Atmospheric Water in Storms with the Nimbus 7 Scanning Multichannel Microwave Radiometer

NASA Technical Reports Server (NTRS)

Katsaros, K. B.

1984-01-01

The new tools for the study of midlattitude cyclones by atmospheric water channels of the scanning multichannel microwave radiometer (SMMR) on Nimbus 7, were discussed. The integrated atmospheric water vapor, total cloud liquid water and rain data were obtained from the Nimbus 7 Scanning Multichannel Microwave Radiometer (SMMR). The frontal structure of several midlattitude cyclones over the North Pacific Ocean as they approached the West Coast of North America were studied. It is found that fronts are consistently located at the leading edge of the strongest gradient in integrated water vapor. The cloud liquid water content has patterns which are consistent with the structure seen in visible and infrared imagery. The rain distribution is a good indicator of frontal location. It is concluded that the onset of rain on the coast can be forecast accurately by simple advection of the SMMR observed rain areas.

Microwave Remote Sensing of Ocean Surface Wind Speed and Rain Rates over Tropical Storms

NASA Technical Reports Server (NTRS)

Swift, C. T.; Dehority, D. C.; Black, P. G.; Chien, J. Z.

1984-01-01

The value of using narrowly spaced frequencies within a microwave band to measure wind speeds and rain rates over tropical storms with radiometers is reviewed. The technique focuses on results obtained in the overflights of Hurricane Allen during 5 and 8 of August, 1980.

Microbiological and meteorological analysis of two Australian dust storms in April 2009.

PubMed

Lim, Natalie; Munday, Chris I; Allison, Gwen E; O'Loingsigh, Tadhg; De Deckker, Patrick; Tapper, Nigel J

2011-12-15

Dust is an important source of bioaerosols including bacteria. In this study, the microbiology and meteorology of specific dust storms in Australia were investigated. The samples were collected from two dust events in April 2009 that were characterised by intense cold fronts that entrained dust from the highly erodible and drought-stricken Mallee and Riverina regions of Victoria and central NSW. In the first storm, the dust travelled eastward over Canberra and Sydney, and in the second storm, the dust travelled east/southeastward over Canberra and Melbourne. Rain fell on both cities during the second dust storm. Dust and rain samples were collected, cultured, and the composition compared using polymerase chain reaction denaturing gradient gel electrophoresis (PCR-DGGE). Multiple bands were evident on DGGE indicative of a diverse microflora, and identification of several bands confirmed the presence of multiple genera and species representing three phyla. Numerous bands represented Bacillus species, and these were present in multiple dust samples collected from both Canberra and Melbourne. Interestingly, the microflora present in rain samples collected in Canberra during the second dust storm was quite different and the DGGE banding patterns from these samples clustered separately to most dust samples collected at the same time. Identification of several DGGE bands and PCR products from these rain samples indicated the presence of Pseudomonas species. These results indicate that Australian dust and rain have a diverse microflora and highlights the contribution of dust events to the distribution of microbes in the environment. Copyright © 2011 Elsevier B.V. All rights reserved.

Magnesium, Iron and Aluminum in LLNL Air Particulate and Rain Samples with Reference to Magnesium in Industrial Storm Water

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

Esser, Bradley K.; Bibby, Richard K.; Fish, Craig

Storm water runoff from the Lawrence Livermore National Laboratory’s (LLNL’s) main site and Site 300 periodically exceeds the Discharge Permit Numeric Action Level (NAL) for Magnesium (Mg) under the Industrial General Permit (IGP) Order No. 2014-0057-DWQ. Of particular interest is the source of magnesium in storm water runoff from the site. This special study compares new metals data from air particulate and precipitation samples from the LLNL main site and Site 300 to previous metals data for storm water from the main site and Site 300 and alluvial sediment from the main site to investigate the potential source of elevatedmore » Mg in storm water runoff. Data for three metals (Mg, Iron {Fe}, and Aluminum {Al}) were available from all media; data for additional metals, such as Europium (Eu), were available from rain, air particulates, and alluvial sediment. To attribute source, this study compared metals concentration data (for Mg, Al, and Fe) in storm water and rain; metal-metal correlations (Mg with Fe, Mg with Al, Al with Fe, Mg with Eu, Eu with Fe, and Eu with Al) in storm water, rain, air particulates, and sediments; and metal-metal ratios ((Mg/Fe, Mg/Al, Al/Fe, Mg/Eu, Eu/Fe, and Eu/Al) in storm water, rain, air particulates and sediments. The results presented in this study are consistent with a simple conceptual model where the source of Mg in storm water runoff is air particulate matter that has dry-deposited on impervious surfaces and subsequently entrained in runoff during precipitation events. Such a conceptual model is consistent with 1) higher concentrations of metals in storm water runoff than in precipitation, 2) the strong correlation of Mg with Aluminum (Al) and Iron (Fe) in both storm water and air particulates, and 3) the similarity in metal mass ratios between storm water and air particulates in contrast to the dissimilarity of metal mass ratios between storm water and precipitation or alluvial sediment. The strong correlation of Mg with Fe and Al and of Fe with Al in storm water and air particulates and the strong association of Mg, Fe, and Al with Eu in air particulates strongly suggests that a dominant source of the Mg in storm water is associated with mineral phases of natural origin. These observations all point to Mg exceedances being associated with natural sources and processes and not with anthropogenic processes or pollutant sources.« less

The relation of radar to cloud area-time integrals and implications for rain measurements from space

NASA Technical Reports Server (NTRS)

Atlas, David; Bell, Thomas L.

1992-01-01

The relationships between satellite-based and radar-measured area-time integrals (ATI) for convective storms are determined, and both are shown to depend on the climatological conditional mean rain rate and the ratio of the measured cloud area to the actual rain area of the storms. The GOES precipitation index of Arkin (1986) for convective storms, an area-time integral for satellite cloud areas, is shown to be related to the ATI for radar-observed rain areas. The quality of GPI-based rainfall estimates depends on how well the cloud area is related to the rain area and the size of the sampling domain. It is also noted that the use of a GOES cloud ATI in conjunction with the radar area-time integral will improve the accuracy of rainfall estimates and allow such estimates to be made in much smaller space-time domains than the 1-month and 5-deg boxes anticipated for the Tropical Rainfall Measuring Mission.

[Research Programs Conducted by the University of Virginia]. Part 1; Aquarius

NASA Technical Reports Server (NTRS)

Fuentes, Jose; Garstang, Michael; Macko, Stephen; Swap, Robert

2001-01-01

The hydrological cycle and the source of water vapor within the Amazon River Basin have important implications on questions of global thermal transport and regional ecological and socioeconomic sustainability. A three tiered approach taking advantage of satellite imagery, tipping buckets, and isotopic storm sampling at three basin sites was used to examine different aspects of regional meteoric water. By combining these techniques, it was possible to correlate observed storm structure with rain rates and intrastorm variations.

Observed and Simulated Radiative and Microphysical Properties of Tropical Convective Storms

NASA Technical Reports Server (NTRS)

DelGenio, Anthony D.; Hansen, James E. (Technical Monitor)

2001-01-01

Increases in the ice content, albedo and cloud cover of tropical convective storms in a warmer climate produce a large negative contribution to cloud feedback in the GISS GCM. Unfortunately, the physics of convective upward water transport, detrainment, and ice sedimentation, and the relationship of microphysical to radiative properties, are all quite uncertain. We apply a clustering algorithm to TRMM satellite microwave rainfall retrievals to identify contiguous deep precipitating storms throughout the tropics. Each storm is characterized according to its size, albedo, OLR, rain rate, microphysical structure, and presence/absence of lightning. A similar analysis is applied to ISCCP data during the TOGA/COARE experiment to identify optically thick deep cloud systems and relate them to large-scale environmental conditions just before storm onset. We examine the statistics of these storms to understand the relative climatic roles of small and large storms and the factors that regulate convective storm size and albedo. The results are compared to GISS GCM simulated statistics of tropical convective storms to identify areas of agreement and disagreement.

The area-time-integral technique to estimate convective rain volumes over areas applied to satellite data - A preliminary investigation

NASA Technical Reports Server (NTRS)

Doneaud, Andre A.; Miller, James R., Jr.; Johnson, L. Ronald; Vonder Haar, Thomas H.; Laybe, Patrick

1987-01-01

The use of the area-time-integral (ATI) technique, based only on satellite data, to estimate convective rain volume over a moving target is examined. The technique is based on the correlation between the radar echo area coverage integrated over the lifetime of the storm and the radar estimated rain volume. The processing of the GOES and radar data collected in 1981 is described. The radar and satellite parameters for six convective clusters from storm events occurring on June 12 and July 2, 1981 are analyzed and compared in terms of time steps and cluster lifetimes. Rain volume is calculated by first using the regression analysis to generate the regression equation used to obtain the ATI; the ATI versus rain volume relation is then employed to compute rain volume. The data reveal that the ATI technique using satellite data is applicable to the calculation of rain volume.

Comparison of radar data versus rainfall data

PubMed Central

Espinosa, B.; Hromadka, T.V.; Perez, R.

2015-01-01

Doppler radar data are increasingly used in rainfall-runoff synthesis studies, perhaps due to radar data availability, among other factors. However, the veracity of the radar data are often a topic of concern. In this paper, three Doppler radar outcomes developed by the United States National Weather Service at three radar sites are examined and compared to actual rain gage data for two separate severe storm events in order to assess accuracy in the published radar estimates of rainfall. Because the subject storms were very intense rainfall events lasting approximately one hour in duration, direct comparisons between the three radar gages themselves can be made, as well as a comparison to rain gage data at a rain gage location subjected to the same storm cells. It is shown that topographic interference with the radar outcomes can be a significant factor leading to differences between radar and rain gage readings, and that care is needed in calibrating radar outcomes using available rain gage data in order to interpolate rainfall estimates between rain gages using the spatial variation observed in the radar readings. The paper establishes and describes•the need for “ground-truthing” of radar data, and•possible errors due to topographic interference. PMID:26649276

Towards evaluating the intensity of convective systems by using GPS radio occultation profiles

NASA Astrophysics Data System (ADS)

Biondi, Riccardo; Steiner, Andrea K.; Kirchengast, Gottfried

2015-04-01

Deep convective systems, also more casually often just called storms, are destructive weather phenomena causing every year many deaths, injuries and damages and accounting for major economic losses in several countries. The number and intensity of such phenomena increased over the last decades in some areas of the globe, including Europe. Damages are mostly caused by strong winds and heavy rain and these parameters are strongly connected to the structure of the storm. Convection over land is usually stronger and deeper than over the ocean and some convective systems, known as supercells, also develop tornadoes through processes which are still mostly unclear. The intensity forecast and monitoring of convective systems is one of the major challenges for meteorology because in-situ measurements during extreme events are too sparse or not reliable and most ongoing satellite missions do not provide suitable time/space coverage. With this study we propose a new method for detecting the convection intensity in terms of rain rate and surface wind speed by using meteorological surface measurements in combination with atmospheric profiles from Global Positioning System (GPS) radio occultation observations, which are available in essentially all weather conditions and with global coverage. The analysis of models indicated a relationship between the cloud top altitude and the intensity of a storm. We thus use GPS radio occultation bending angle profiles for detecting the storm's cloud top altitude and we correlate this value to the rain rate and wind speed measured by meteorological station networks in two different regions, the WegenerNet climate station network (South-Eastern Styria, Austria) and the Atmospheric Radiation Measurement site (ARM, Southern Great Plains, USA), respectively. The results show a good correlation between the cloud top altitude and the maximum rain rate in the monitored areas, while this is not found for maximum wind speed. We conclude from this initial study that for land convective systems the cloud top altitude is strongly connected to the rain intensity and that GPS radio occultation observations show encouraging potential to improve the intensity nowcasting and detection of such kind of severe weather phenomena.

Impacts of a heavy storm of rain upon dissolved and particulate organic C, N and P in the main river of a vegetation-rich basin area in Japan.

PubMed

Li, Fusheng; Yuasa, Akira; Muraki, Yuzo; Matsui, Yoshihiko

2005-06-01

The impacts of a heavy storm of rain upon the dissolved and particulate organic matter (OM), nitrogen (N) and phosphorus (P) in the main river of the vegetation-rich Nagara River basin were investigated using water samples collected along the river line during a critical typhoon-induced heavy rain storm event. Besides, based on a high performance size-exclusion chromatography (HPSEC) system, the variance of dissolved OM (DOM) in its molecular weight (MW) characteristics was also assessed. From the MW standpoint, DOM components merged into the river along the river line resembled those present in its headwater. The MW range changed only slightly from 1010 to 5900 at the upstream (US), to 1130-5900 and 1200-5900 Da at the midstream (MS) and downstream (DS), respectively, while the corresponding weight-averaged MW (M(w)) decreased from 3669 to 3330 and 2962 Da. The heavy storm of rain enhanced the content of DOM; however, apart from a small larger-MW fraction (about 5900-6800 Da), the newly emerged DOM constituents exhibited an MW range similar to those existed before the storm. Due also to the storm of rain, total P and N (TP and TN) changed markedly in the ranges of 6.6-11.9, 8.3-40.6 and 48.4-231.3 microg/l for TP, and 145.4-296.0, 502.2-1168.7 and 1342.7-1927.3 microg/l for TN at the US, MS and DS, respectively. The larger values of TP and TN generally appeared for samples at elevated river water levels. The enhanced presence of P was found largely attributed to its particulate form; while, for N, the contribution from its dissolved form was significant. The newly emerged suspended particles via the storm-water contained lower content of OM, N and P, and a general decreasing trend of the particulate OM, N and P along the river line was also confirmed. The C/N ratio in the dissolved form varied in 0.7-6.7 and decreased downstream, while, that in the particulate form 2.3-17.3. Suspended particles that emerged in the river water during the storm exhibited larger C/N values. N/P in both dissolved and particulate forms varied in the ranges of 2.2-17.1 and 12.9-444.9, respectively, and a general trend of either increasing or decreasing in relation to the storm of rain was not revealed.

Rain Volume Estimation over Areas Using Satellite and Radar Data

NASA Technical Reports Server (NTRS)

Doneaud, A. A.; Miller, J. R., Jr.; Johnson, L. R.; Vonderhaar, T. H.; Laybe, P.

1984-01-01

The application of satellite data to a recently developed radar technique used to estimate convective rain volumes over areas on a dry environment (the northern Great Plains) is discussed. The area time integral technique (ATI) provides a means of estimating total rain volumes over fixed and floating target areas of the order of 1,000 to 100,000 km(2) for clusters lasting 40 min. The basis of the method is the existence of a strong correlation between the area coverage integrated over the lifetime of the storm (ATI) and the rain volume. One key element in this technique is that it does not require the consideration of the structure of the radar intensities inside the area coverage to generate rain volumes, but only considers the rain event per se. This fact might reduce or eliminate some sources of error in applying the technique to satellite data. The second key element is that the ATI once determined can be converted to total rain volume by using a constant factor (average rain rate) for a given locale.

A long-lived mesoscale convective complex. II - Evolution and structure of the mature complex

NASA Technical Reports Server (NTRS)

Wetzel, P. J.; Cotton, W. R.; Mcanelly, R. L.

1983-01-01

The present investigation is concerned with an eight-day episode, during which a series of mesoscale convective complexes (MCC) developed and moved across the country, producing heavy rain and some flooding over an extensive region. An overview of the considered period from August 3 to August 10, 1977 is presented, and the evolution of the August 4 storm is examined. The structure of the mature MCC is discussed, taking into account the August 4-5 storm, a comparative case involving the August 3-4 storm, and an evaluation of the observed phenomena. It is concluded that MCCs are basically tropical in nature and that their dynamics are dominated by buoyant accelerations. It was found that the MCCs developed a warm-core, divergent anticyclonic flow pattern in the upper troposphere which was not present prior to the development of convection. A similar structure is observed in tropical cloud clusters.

Tropical warm pool rainfall variability and impact on upper ocean variability throughout the Madden-Julian oscillation

NASA Astrophysics Data System (ADS)

Thompson, Elizabeth J.

Heating and rain freshening often stabilize the upper tropical ocean, bringing the ocean mixed layer depth to the sea surface. Thin mixed layer depths concentrate subsequent fluxes of heat, momentum, and freshwater in a thin layer. Rapid heating and cooling of the tropical sea surface is important for controlling or triggering atmospheric convection. Ocean mixed layer depth and SST variability due to rainfall events have not been as comprehensively explored as the ocean's response to heating or momentum fluxes, but are very important to understand in the tropical warm pool where precipitation exceeds evaporation and many climate phenomena such as ENSO and the MJO (Madden Julian Oscillation) originate. The first part of the dissertation investigates tropical, oceanic convective and stratiform rainfall variability and determines how to most accurately estimate rainfall accumulation with radar from each rain type. The second, main part of the dissertation uses central Indian Ocean salinity and temperature microstructure measurements and surrounding radar-derived rainfall maps throughout two DYNAMO MJO events to determine the impact of precipitating systems on upper-ocean mixed layer depth and resulting SST variability. The ocean mixed layer was as shallow as 0-5 m during 528/1071 observation hours throughout 2 MJOs (54% of the data record). Out of 43 observation days, thirty-eight near-surface mixed layer depth events were attributed to freshwater stabilization, called rain-formed mixed layers (RFLs). Thirty other mixed layer stratification events were classified as diurnal warm layers (DWLs) due to stable temperature stratification by daytime heating. RFLs and DWLs were observed to interact in two ways: 1) RFLs fill preexisting DWLs and add to total near-surface mixed layer stratification, which occurred ten times; 2) RFLs last long enough to heat, creating a new DWL on top of the RFL, which happened nine times. These combination stratification events were responsible for the highest SST warming rates and some of the highest SSTs leading up to the most active precipitation and wind stage of the each MJO. DWLs without RFL interaction helped produce the highest SSTs in suppressed MJO conditions. As storm intensity, frequency, duration, and the ability of storms to maintain stratiform rain areas increased, RFLS became more common in the disturbed and active MJO phases. Along with the barrier layer, DWL and RFL stratification events helped suppress wind-mixing, cooling, and mixed layer deepening throughout the MJO. We hypothesize that both salinity and temperature stratification events, and their interactions, are important for controlling SST variability and therefore MJO initiation in the Indian Ocean. Most RFLs were caused by submesoscale and mesoscale convective systems with stratiform rain components and local rain accumulations above 10 mm but with winds mostly below 8 m s-1. We hypothesize that the stratiform rain components of storms helped stratify the ocean by providing weak but widespread, steady, long-lived freshwater fluxes. Although generally limited to rain rates ≤ 10 mm hr-1, it is demonstrated that stratiform rain can exert a strong buoyancy flux into the ocean, i.e. as high as maximum daytime solar heating. Storm morphology and the preexisting vertical structure of ocean stability were critical in determining ocean mixed layer depth variability in the presence of rain. Therefore, we suggest that high spatial and temporal resolution coupled ocean-atmosphere models that can parameterize or resolve storm morphology as well as ocean mixed layer and barrier layer evolution are needed to reproduce the diurnal and intraseasonal SST variability documented throughout the MJO.

KSC-08pd2424

NASA Image and Video Library

2008-08-21

CAPE CANAVERAL, Fla. – Wind and rain from Tropical Storm Fay pummel the area near the Vehicle Assembly Building at NASA's Kennedy Space Center. The storm passed over the center Aug. 20 and then stalled offshore, bringing with it heavy rain and tropical storm force wind. Kennedy closed Aug. 19 because of Fay and reopened for normal operations Aug. 22. Based on initial assessments, there was no damage to space flight hardware, such as the space shuttles and Hubble Space Telescope equipment. Some facilities did sustain minor damage. Photo credit: NASA/Jack Pfaller

Consumer demand for green stormwater management technology in an urban setting: The case of Chicago rain barrels

NASA Astrophysics Data System (ADS)

Ando, Amy W.; Freitas, Luiz P. C.

2011-12-01

Hydrological disruption and water pollution from urbanization can be reduced if households in urban areas adopt decentralized storm water controls. We study a citywide municipal subsidized rain-barrel program in the third biggest city in the United States, Chicago, to explore what factors influence whether households purchase this sort of green storm water management technology in an urban setting. Specifically, we regress census-tract level data on the number of rain barrels adopted in different parts of the city on socioeconomic variables, data on local flood frequency, and features of the housing stock. We find that rain-barrel purchases are not correlated with local levels of flooding, even though city residents were told by program managers that rain barrels could alleviate local flooding. Instead, rain barrels are heavily concentrated in places with high-income attitudinally green populations. We do find more rain barrels were adopted in places close to rain-barrel distribution points and near sites of hydrological information campaigns; thus, policy makers might increase green-technology adoption in areas where they can do the most good by reducing transaction costs and providing education programs to those areas. Finally, our results indicate that owner occupancy is positively correlated with green-technology adoption. Low-rise rental housing may have inefficiently low levels of adoption, such that city managers might want to develop programs to encourage storm water management investments by landlords who do not live in their own properties.

Storms in Ancient Egypt: the Examples of Historical Natural Disasters Impacts on the Society

NASA Astrophysics Data System (ADS)

Petrova, Anastasia

2013-04-01

Though rain storms are infrequent in Egypt, which is normally a rainless country, some Ancient Egyptian texts give accounts of violent storms and rains. Actually, even small amounts of rain in that area could cause huge impact, as none of the water was absorbed by soil, and, running off, it could create dangerous torrents. The Tempest stele, circa 1550 BC, recounts a highly destructive storm happened during the reign of Ahmose I, the king of Egypt's 18 dynasty. The catastrophy is described in details, including the specific noise, overall darkness, torrent so that no torch could be lit. Many houses were washed into the river, temples, tombs and pyramids damaged and collapsed. The stele commemorates the restoration works made by the king who was able to cope with this great disaster and "re-establish the Two Lands". Some egyptologists believe that this event is related to the Minoan eruption of Thera, but this is unlikely given the description in the stele.

Radar research on thunderstorms and lightning

NASA Technical Reports Server (NTRS)

Rust, W. D.; Doviak, R. J.

1982-01-01

Applications of Doppler radar to detection of storm hazards are reviewed. Normal radar sweeps reveal data on reflectivity fields of rain drops, ionized lightning paths, and irregularities in humidity and temperature. Doppler radar permits identification of the targets' speed toward or away from the transmitter through interpretation of the shifts in the microwave frequency. Wind velocity fields can be characterized in three dimensions by the use of two radar units, with a Nyquist limit on the highest wind speeds that may be recorded. Comparisons with models numerically derived from Doppler radar data show substantial agreement in storm formation predictions based on information gathered before the storm. Examples are provided of tornado observations with expanded Nyquist limits, gust fronts, turbulence, lightning and storm structures. Obtaining vertical velocities from reflectivity spectra is discussed.

Proceedings from the Annual Army Environmental R&D Symposium (16th) Held 23-25 June 1992 at Fort Magruder Inn and Conference Center, Williamsburg, Virginia

DTIC Science & Technology

1992-06-01

methods of selecting sites, monitoring flow, and sampling 4 409 runoff. Also, there are some observations on storm water quality findings and some...turning off the flow meters until a rain event is imminent. Make sure you pack plenty of flashlights for night rains. 6. STORM WATER QUALITY SUMMARY

Radar and microphysical characteristics of convective storms simulated from a numerical model using a new microphysical parameterization

NASA Technical Reports Server (NTRS)

Ferrier, Brad S.; Tao, Wei-Kuo; Simpson, Joanne

1991-01-01

The basic features of a new and improved bulk-microphysical parameterization capable of simulating the hydrometeor structure of convective systems in all types of large-scale environments (with minimal adjustment of coefficients) are studied. Reflectivities simulated from the model are compared with radar observations of an intense midlatitude convective system. Simulated reflectivities using the novel four-class ice scheme with a microphysical parameterization rain distribution at 105 min are illustrated. Preliminary results indicate that this new ice scheme works efficiently in simulating midlatitude continental storms.

Seasonal timing of first rain storms affects rare plant population dynamics

USGS Publications Warehouse

Levine, J.M.; McEachern, A.K.; Cowan, C.

2011-01-01

A major challenge in forecasting the ecological consequences of climate change is understanding the relative importance of changes to mean conditions vs. changes to discrete climatic events, such as storms, frosts, or droughts. Here we show that the first major storm of the growing season strongly influences the population dynamics of three rare and endangered annual plant species in a coastal California (USA) ecosystem. In a field experiment we used moisture barriers and water addition to manipulate the timing and temperature associated with first major rains of the season. The three focal species showed two- to fivefold variation in per capita population growth rates between the different storm treatments, comparable to variation found in a prior experiment imposing eightfold differences in season-long precipitation. Variation in germination was a major demographic driver of how two of three species responded to the first rains. For one of these species, the timing of the storm was the most critical determinant of its germination, while the other showed enhanced germination with colder storm temperatures. The role of temperature was further supported by laboratory trials showing enhanced germination in cooler treatments. Our work suggests that, because of species-specific cues for demographic transitions such as germination, changes to discrete climate events may be as, if not more, important than changes to season-long variables.

Seasonal timing of first rain storms affects rare plant population dynamics.

PubMed

Levine, Jonathan M; McEachern, A Kathryn; Cowan, Clark

2011-12-01

A major challenge in forecasting the ecological consequences of climate change is understanding the relative importance of changes to mean conditions vs. changes to discrete climatic events, such as storms, frosts, or droughts. Here we show that the first major storm of the growing season strongly influences the population dynamics of three rare and endangered annual plant species in a coastal California (USA) ecosystem. In a field experiment we used moisture barriers and water addition to manipulate the timing and temperature associated with first major rains of the season. The three focal species showed two- to fivefold variation in per capita population growth rates between the different storm treatments, comparable to variation found in a prior experiment imposing eightfold differences in season-long precipitation. Variation in germination was a major demographic driver of how two of three species responded to the first rains. For one of these species, the timing of the storm was the most critical determinant of its germination, while the other showed enhanced germination with colder storm temperatures. The role of temperature was further supported by laboratory trials showing enhanced germination in cooler treatments. Our work suggests that, because of species-specific cues for demographic transitions such as germination, changes to discrete climate events may be as, if not more, important than changes to season-long variables.

Spotter's Guide for Identifying and Reporting Severe Local Storms.

ERIC Educational Resources Information Center

National Oceanic and Atmospheric Administration (DOC), Rockville, MD.

This guide is designed to assist personnel working in the National Weather Service's Severe Local Storm Spotter Networks in identifying and reporting severe local storms. Provided are pictures of cloud types for severe storms including tornadoes, hail, thunder, lightning, heavy rains, and waterspouts. Instructions for key indications to watch for…

KSC-08pd2426

NASA Image and Video Library

2008-08-21

CAPE CANAVERAL, Fla. – The large windows of a building at NASA's Kennedy Space Center are covered by plywood and sandbags to protect against the wind and rain driven by Tropical Storm Fay. The storm passed over the center Aug. 20 and then stalled offshore, bringing with it heavy rain and tropical storm force wind. Kennedy closed Aug. 19 because of Fay and reopened for normal operations Aug. 22. Based on initial assessments, there was no damage to space flight hardware, such as the space shuttles and Hubble Space Telescope equipment. Some facilities did sustain minor damage. Photo credit: NASA/Jack Pfaller

An evaluation of WRF microphysics schemes for simulating the warm-type heavy rain over the Korean peninsula

NASA Astrophysics Data System (ADS)

Song, Hwan-Jin; Sohn, Byung-Ju

2018-01-01

The Korean peninsula is the region of distinctly showing the heavy rain associated with relatively low storm height and small ice water content in the upper part of cloud system (i.e., so-called warm-type heavy rainfall). The satellite observations for the warmtype rain over Korea led to a conjecture that the cloud microphysics parameterization suitable for the continental deep convection may not work well for the warm-type heavy rainfall over the Korean peninsula. Therefore, there is a growing need to examine the performance of cloud microphysics schemes for simulating the warm-type heavy rain structures over the Korean peninsula. This study aims to evaluate the capabilities of eight microphysics schemes in the Weather Research and Forecasting (WRF) model how warmtype heavy rain structures can be simulated, in reference to the Tropical Rainfall Measuring Mission (TRMM) Precipitation Radar (PR) reflectivity measurements. The results indicate that the WRF Double Moment 6-class (WDM6) scheme simulated best the vertical structure of warm-type heavy rain by virtue of a reasonable collisioncoalescence process between liquid droplets and the smallest amount of snow. Nonetheless the WDM6 scheme appears to have limitations that need to be improved upon for a realistic reflectivity structure, in terms of the reflectivity slope below the melting layer, discontinuity in reflectivity profiles around the melting layer, and overestimation of upper-level reflectivity due to high graupel content.

An Evaluation of WRF Microphysics Schemes for Simulating the Warm-Type Heavy Rain over the Korean Peninsula

NASA Astrophysics Data System (ADS)

Song, Hwan-Jin; Sohn, Byung-Ju

2018-05-01

The Korean peninsula is the region of distinctly showing the heavy rain associated with relatively low storm height and small ice water content in the upper part of cloud system (i.e., so-called warm-type heavy rainfall). The satellite observations for the warm-type rain over Korea led to a conjecture that the cloud microphysics parameterization suitable for the continental deep convection may not work well for the warm-type heavy rainfall over the Korean peninsula. Therefore, there is a growing need to examine the performance of cloud microphysics schemes for simulating the warm-type heavy rain structures over the Korean peninsula. This study aims to evaluate the capabilities of eight microphysics schemes in the Weather Research and Forecasting (WRF) model how warm-type heavy rain structures can be simulated, in reference to the Tropical Rainfall Measuring Mission (TRMM) Precipitation Radar (PR) reflectivity measurements. The results indicate that the WRF Double Moment 6-class (WDM6) scheme simulated best the vertical structure of warm-type heavy rain by virtue of a reasonable collision-coalescence process between liquid droplets and the smallest amount of snow. Nonetheless the WDM6 scheme appears to have limitations that need to be improved upon for a realistic reflectivity structure, in terms of the reflectivity slope below the melting layer, discontinuity in reflectivity profiles around the melting layer, and overestimation of upper-level reflectivity due to high graupel content.

Satellite-observed latent heat release in a tropical cyclone

NASA Technical Reports Server (NTRS)

Adler, R. F.; Rodgers, E. B.

1976-01-01

Earlier observational estimates of storm latent heat release (LHR) have been made using a moisture budget approach. The present paper summarizes results for the tropical cyclone Nora, using the electrically scanning microwave radiometer (ESMR) on Nimbus 5, on the basis of the theoretical brightness temperature/rainfall rate relationship for an assumed freezing level of 5 km. The LHR of the storm as a function of time for a circular area of radius 4 deg latitude positioned on the circulation center is discussed along with the calculated mean rain rate as a function of distance from the storm center. The contribution of the various magnitudes of rain rates to the total LHR of the storm is examined. It is concluded that the Nimbus 5 ESMR data can be used to determine the LHR characteristics of tropical cyclones and are potentially useful in the monitoring of such storms. The calculations for Typhoon Nora indicate that the LHR for the storm increases as the storm intensifies from a tropical disturbance to a typhoon.

Rainfall estimation over oceans from scanning multichannel microwave radiometer and special sensor microwave/imager microwave data

NASA Technical Reports Server (NTRS)

Prabhakara, C.; Dalu, G.; Liberti, G. L.; Nucciarone, J. J.; Suhasini, R.

1991-01-01

The brightness temperature (T sub b) measured at 37 GHz shows fairly strong emission from rain, and only slight effects caused by scattering by ice above the rain clouds. At frequencies below 37 GHz, were the fov is larger and the volume extinction coefficient is weaker, it is found that the observations do not yield appreciable additional information about rain. At 85 GHz (fov = 15 km), where the volume extinction is considerably larger, direct information about rain below the clouds is usually masked. Based on the above ideas, 37 GHz observations with a 30 km fov from SMMR and SSM/I are selected to develop an empirical method for the estimation of rain rate. In this method, the statistics of the observed T sub b's at 37 GHz in a rain storm are related to the rain rate statistics in that storm. The underestimation of rain rate, arising from the inability of the radiometer to respond sensitively to rain rate above a given threshold, is rectified in this technique with the aid of two parameters that depend on the total water vapor content in the atmosphere. The retrieved rain rates compare favorably with radar observations and monthly mean global maps of rain derived from this technique over the oceans.

Rainfall estimation over oceans from SMMR and SSM/I microwave data

NASA Technical Reports Server (NTRS)

Prabhakara, C.; Dalu, G.; Liberti, G. L.; Nucciarone, J. J.; Suhasini, R.

1992-01-01

The brightness temperature (T sub b) measured at 37 GHz shows fairly strong emission from rain, and only slight effects caused by scattering by ice above the rain clouds. At frequencies below 37 GHz, where the FOV is larger and the volume extinction coefficient is weaker, it is found that the observations do not yield appreciable additional information about rain. At 85 GHz (FOV = 15 km), where the volume extinction is considerably larger, direct information about rain below the clouds is usually masked. Based on the above idea, 37 GHz observations with a 30 km FOV from SMMR and SSM/I are selected to develop an empirical method for the estimation of rain rate. In this method, the statistics of the observed T sub b's at 37 GHz in a rain storm are related to the rain rate statistics in that storm. The underestimation of rain rate, arising from the inability of the radiometer to respond sensitively to rain rate above a given threshold is rectified in this technique with the aid of two parameters that depend on the total water vapor content in the atmosphere. The retrieved rain rates compare favorably with radar observations and monthly mean global maps of rain derived from this technique over the oceans.

Rainfall Stochastic models

NASA Astrophysics Data System (ADS)

Campo, M. A.; Lopez, J. J.; Rebole, J. P.

2012-04-01

This work was carried out in north of Spain. San Sebastian A meteorological station, where there are available precipitation records every ten minutes was selected. Precipitation data covers from October of 1927 to September of 1997. Pulse models describe the temporal process of rainfall as a succession of rainy cells, main storm, whose origins are distributed in time according to a Poisson process and a secondary process that generates a random number of cells of rain within each storm. Among different pulse models, the Bartlett-Lewis was used. On the other hand, alternative renewal processes and Markov chains describe the way in which the process will evolve in the future depending only on the current state. Therefore they are nor dependant on past events. Two basic processes are considered when describing the occurrence of rain: the alternation of wet and dry periods and temporal distribution of rainfall in each rain event, which determines the rainwater collected in each of the intervals that make up the rain. This allows the introduction of alternative renewal processes and Markov chains of three states, where interstorm time is given by either of the two dry states, short or long. Thus, the stochastic model of Markov chains tries to reproduce the basis of pulse models: the succession of storms, each one composed for a series of rain, separated by a short interval of time without theoretical complexity of these. In a first step, we analyzed all variables involved in the sequential process of the rain: rain event duration, event duration of non-rain, average rainfall intensity in rain events, and finally, temporal distribution of rainfall within the rain event. Additionally, for pulse Bartlett-Lewis model calibration, main descriptive statistics were calculated for each month, considering the process of seasonal rainfall in each month. In a second step, both models were calibrated. Finally, synthetic series were simulated with calibration parameters; series were recorded every ten minutes and hourly, aggregated. Preliminary results show adequate simulation of the main features of rain. Main variables are well simulated for time series of ten minutes, also over one hour precipitation time series, which are those that generate higher rainfall hydrologic design. For coarse scales, less than one hour, rainfall durations are not appropriate under the simulation. A hypothesis may be an excessive number of simulated events, which causes further fragmentation of storms, resulting in an excess of rain "short" (less than 1 hour), and therefore also among rain events, compared with the ones that occur in the actual series.

NASA Sees Winter's Northeastern U.S. Snowcover Extend Farther South

NASA Image and Video Library

2015-02-17

A winter storm that moved through the Mid-Atlantic on Feb. 16 and 17, 2015 extended the northeastern U.S. snowcover farther south. Until this storm hit, southern New Jersey and southeastern Pennsylvania appeared snow-free on satellite imagery from the previous week. The overnight storm blanketed the entire states of New Jersey and Pennsylvania, as seen on this Feb. 16 image. The image was taken from the MODIS or Moderate Resolution Imaging Spectroradiometer instrument that flies aboard NASA's Terra satellite. The snow cover from the storm actually extended even farther south than the image. Snowfall also blanketed West Virginia, Kentucky, Maryland, Delaware and Virginia, while freezing rain and icy conditions affected the Carolinas, Tennessee and Georgia. On Feb. 17, 2015, NOAA's National Weather Service noted "The winter storm that brought widespread snow, sleet and freezing rain to parts of the south-central U.S. and Mid-Atlantic will wind down as it moves offshore Tuesday. Lingering snow and freezing rain is possible early Tuesday for parts of the Northeast and mid-Atlantic, with rain across parts of the Southeast." Credit: NASA/GSFC/Jeff Schmaltz/MODIS Land Rapid Response Team NASA image use policy. NASA Goddard Space Flight Center enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission. Follow us on Twitter Like us on Facebook Find us on Instagram

Satellite microwave observations of a storm complex: A comparative analysis

NASA Technical Reports Server (NTRS)

Martin, D. W.

1985-01-01

The hypothesis that cold events correspond to a particular stage in a class of thunderstorms was tested. That class is a storms class which updrafts are: (1) strong, broad and moist, and (2) extend well above the freezing level. Condition (1) implies strong mesoscale forcing. Condition (2) implies a tall updraft or a relatively low freezing level. Such storms should have big, intense radar echoes and cold, fast-growing anvils. The thunderstorm events were analyzed by radar, rain gauge and GOES infrared observations. Radar was the starting point for detection and definition of the hypothesized thunderstorms. The radar signature is compared to the signature of the storm in rain gauge observations, satellite infrared images and satellite microwave images.

An estimation of the condensation rates in three severe storm systems from satellite observations of the convective mass flux

NASA Technical Reports Server (NTRS)

Mack, R. A.; Wylie, D. P.

1982-01-01

A technique was developed for estimating the condensation rates of convective storms using satellite measurements of cirrus anvil expansion rates and radiosonde measurements of environmental water vapor. Three cases of severe convection in Oklahoma were studied and a diagnostic model was developed for integrating radiosonde data with satellite data. Two methods were used to measure the anvil expansion rates - the expansion of isotherm contours on infrared images, and the divergent motions of small brightness anomalies tracked on the visible images. The differences between the two methods were large as the storms developed, but these differences became small in the latter stage of all three storms. A comparison between the three storms indicated that the available moisture in the lowest levels greatly affected the rain rates of the storms. This was evident from both the measured rain rates of the storms and the condensation rates estimated by the model. The possibility of using this diagnostic model for estimating the intensities of convective storms also is discussed.

A modified ATI technique for nowcasting convective rain volumes over areas. [area-time integrals

NASA Technical Reports Server (NTRS)

Makarau, Amos; Johnson, L. Ronald; Doneaud, Andre A.

1988-01-01

This paper explores the applicability of the area-time-integral (ATI) technique for the estimation of the growth portion only of a convective storm (while the rain volume is computed using the entire life history of the event) and for nowcasting the total rain volume of a convective system at the stage of its maximum development. For these purposes, the ATIs were computed from the digital radar data (for 1981-1982) from the North Dakota Cloud Modification Project, using the maximum echo area (ATIA) no less than 25 dBz, the maximum reflectivity, and the maximum echo height as the end of the growth portion of the convective event. Linear regression analysis demonstrated that correlations between total rain volume or the maximum rain volume versus ATIA were the strongest. The uncertainties obtained were comparable to the uncertainties which typically occur in rain volume estimates obtained from radar data employing Z-R conversion followed by space and time integration. This demonstrates that the total rain volume of a storm can be nowcasted at its maximum stage of development.

A Synoptic- and Planetary-Scale Analysis of Widespread North American Ice Storms

NASA Astrophysics Data System (ADS)

McCray, C.; Gyakum, J. R.; Atallah, E.

2017-12-01

Freezing rain can have devastating impacts, particularly when it persists for many hours. Predicting the precise temperature stratification necessary for long duration freezing rain events remains an important forecast challenge. To better elucidate the conditions responsible for the most severe events, we concentrate on surface observations of long-duration (6 or more hours) freezing rain events over North America from 1979-2016. Furthermore, we analyze cases in which multiple stations observe long-duration events simultaneously. Following these cases over successive days allows us to generate maps of freezing rain "tracks." We then categorize recurring geographic patterns to examine the meteorological conditions leading to these events. While freezing rain is most frequently observed in the northeastern United States and southeastern Canada, long-duration events have affected areas as far south as the Gulf Coast. Notably, a disproportionately large number of very long duration (18 or more hours) events have occurred in the Southern Plains states relative to the climatological annual frequency of freezing rain there. Classification of individual cases shows that most of these very long duration events are associated with a recurring pattern which produces freezing rain along a southwest-northeast swath from Texas/Oklahoma into the northeastern U.S. and eastern Canada. Storms classified within this pattern include the January 1998 and December 2013 ice storms. While this pattern is the most widespread, additional spatially extensive patterns occur. One of these areas extends from the Southern Plains eastward along the Gulf Coast to Georgia and the Carolinas. A third category of events extends from the Upper Midwest into the northeastern U.S. and southeastern Canada. The expansive areal extent and long duration of these events make them especially problematic. An analysis of the planetary- to synoptic-scale settings responsible for these cases and the differences among individual storms is performed to provide forecasters with additional tools/insight towards the prediction of these damaging weather events.

Hurricanes

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A hurricane is a severe type of tropical storm. Hurricanes produce high winds, heavy rains and thunderstorms. ... exceed 155 miles per hour. Hurricanes and tropical storms can also spawn tornadoes and lead to flooding. ...

Electric Field and Lightning Observations in the Core of Category 5 Hurricane Emily

NASA Technical Reports Server (NTRS)

Blakeslee, Richard; Mach, Doug M.; Bateman, Monte G.; Bailey, Jeff C.

2007-01-01

Significant electric fields and lightning activity associated with Hurricane Emily were observed from a NASA high-altitude ER-2 aircraft on July 17, 2005 while this storm developed as a compact but intense category 5 hurricane in the Caribbean south of Cuba. The electrical measurements were acquired as part of the NASA sponsored Tropical Cloud Systems and Processes (TCSP) experiment. In addition to the electrical measurements, the aircraft's remote sensing instrument complement also included active radars, passive microwave, visible and infrared radiometers, and a temperature sounder providing details on the dynamical, microphysical, and environmental structure, characteristics and development of this intense storm. Cloud-to-ground lightning location data from Vaisala's long range lightning detection network were also acquired and displayed in real-time along with electric fields measured at the aircraft. These data and associated display also supported aircraft guidance and vectoring during the mission. During the observing period, flash rates in excess of 3 to 5 flashes per minute, as well as large electric field and field change values were observed as the storm appeared to undergo periods of intensification, especially in the northwest quadrant in the core eyewall regions. This is in contrast to most hurricanes that tend to be characterized by weak electrification and little or no lightning activity except in the outer rain bands. It should be noted that this storm also had significant lightning associated with its rain bands.

Rain fall data for the design of sewer pipe systems

NASA Astrophysics Data System (ADS)

Arnell, V.

1982-03-01

A comparison of designs of sewer pipes for different types of rainfall data is presented. Local coefficients were evaluated from an 18-year historical rainfall record for the following design storms: The Average-Intensity-Duration Design Storm, The Chicago Design Storm, The Sifalda Design Storm, The Illinois State Water Survey Design Storm, and The Flood Studies Report Design Storm. Historical rainfalls as well as the above design storms were used for the calculations of peak-flow values.

What Would Happen to Superstorm Sandy Under the Influence of a Substantially Warmer Atlantic Ocean?

NASA Technical Reports Server (NTRS)

Lau, William K. M.; Shi, J. J.; Tao, W. K.; Kim, K. M.

2016-01-01

Based on ensemble numerical simulations, we find that possible responses of Sandy-like superstorms under the influence of a substantially warmer Atlantic Ocean bifurcate into two groups. In the first group, storms are similar to present-day Sandy from genesis to extratropical transition, except they are much stronger, with peak Power Destructive Index (PDI) increased by 50-80%, heavy rain by 30-50%, and maximum storm size (MSS) approximately doubled. In the second group, storms amplify substantially over the interior of the Atlantic warm pool, with peak PDI increased by 100-160%, heavy rain by 70-180%, and MSS more than tripled compared to present-day Superstorm Sandy. These storms when exiting the warm pool, recurve northeastward out to sea, subsequently interact with the developing midlatitude storm by mutual counterclockwise rotation around each other and eventually amplify into a severe Northeastern coastal storm, making landfall over the extreme northeastern regions from Maine to Nova Scotia.

Validation of Satellite-based Rainfall Estimates for Severe Storms (Hurricanes & Tornados)

NASA Astrophysics Data System (ADS)

Nourozi, N.; Mahani, S.; Khanbilvardi, R.

2005-12-01

Severe storms such as hurricanes and tornadoes cause devastating damages, almost every year, over a large section of the United States. More accurate forecasting intensity and track of a heavy storm can help to reduce if not to prevent its damages to lives, infrastructure, and economy. Estimating accurate high resolution quantitative precipitation (QPE) from a hurricane, required to improve the forecasting and warning capabilities, is still a challenging problem because of physical characteristics of the hurricane even when it is still over the ocean. Satellite imagery seems to be a valuable source of information for estimating and forecasting heavy precipitation and also flash floods, particularly for over the oceans where the traditional ground-based gauge and radar sources cannot provide any information. To improve the capability of a rainfall retrieval algorithm for estimating QPE of severe storms, its product is evaluated in this study. High (hourly 4km x 4km) resolutions satellite infrared-based rainfall products, from the NESDIS Hydro-Estimator (HE) and also PERSIANN (Precipitation Estimation from Remotely Sensed Information using an Artificial Neural Networks) algorithms, have been tested against NEXRAD stage-IV and rain gauge observations in this project. Three strong hurricanes: Charley (category 4), Jeanne (category 3), and Ivan (category 3) that caused devastating damages over Florida in the summer 2004, have been considered to be investigated. Preliminary results demonstrate that HE tends to underestimate rain rates when NEXRAD shows heavy storm (rain rates greater than 25 mm/hr) and to overestimate when NEXRAD gives low rainfall amounts, but PERSIANN tends to underestimate rain rates, in general.

Midweek Increase in U.S. Summer Rain and Storm Heights, Suggests Air Pollution Invigorates Rainstorms

NASA Technical Reports Server (NTRS)

Bell, Thomas L.; Rosenfeld, Daniel; Kim, Kyu-Myong; Yoo, Jung-Moon; Hahnenberger, Maura

2007-01-01

Tropical Rainfall Measuring Mission (TRMM) satellite data show a significant midweek increase in summertime rainfall over the southeast U.S., due to afternoon intensification. TRMM radar data show a significant midweek increase in rain area and in the heights reached by afternoon storms. Weekly variations in model-reanalysis wind patterns over the region and in rain-gauge data are consistent with the satellite data. A midweek decrease of rainfall over the nearby Atlantic is also seen. EPA measurements of particulate concentrations show a midweek peak over much of the U.S. These observations are consistent with the theory that anthropogenic air pollution suppresses cloud-drop coalescence and early rainout during the growth of thunderstorms over land, allowing more water to be carried above the 0 C isotherm, where freezing yields additional latent heat, invigorating the storms--most dramatically evidenced by the shift in the midweek distribution of afternoon-storm heights--and producing large ice hydrometeors. The enhanced convection induces regional convergence, uplifting and an overall increase of rainfall. Compensating downward air motion suppresses convection over the adjacent ocean areas. Pre-TRMM-era data suggest that the weekly cycle only became strong enough to be detectable beginning in the 1980's. Rain-gauge data also suggest that a weekly cycle may have been detectable in the 1940's, but with peak rainfall on Sunday or Monday, possibly explained by the difference in composition of aerosol pollution at that time. This "weekend effect" may thus offer climate researchers an opportunity to study the regional climate-scale impact of aerosols on storm development and monsoon-like circulation.

Satellite Sees Winter Storm March Over Mid-Atlantic

NASA Image and Video Library

2014-03-03

On March 3, a major winter storm brought snow to the mid-Atlantic, freezing rain to the Carolinas and rain and some freezing rain to the Gulf Coast states. NOAA's GOES-East satellite captured an image of the clouds associated with the winter storm on March 3 at 12:45 p.m. EST (1745 UTC)/ as it continued on its march over the mid-Atlantic. Bands of snow and sometimes heavy snow affected the Washington, D.C., region, Delaware and central Virginia, stretching west into West Virginia and eastern Kentucky. Snow also stretched back into the Ohio and Tennessee valleys while rain and freezing rain affected the Carolinas, and while the Gulf Coast states received rain. National Weather Service Winter Storm Warnings remained in effect until 6 p.m. EST on March 3 for Washington, D.C., and Baltimore, Md. In Richmond and Norfolk, Va., the Winter Storm warnings were in effect for six additional hours ending at midnight. On March 3, NOAA's National Weather Prediction Center in College Park, Md., noted the late-season winter storm will continue to shift eastward through the Tennessee Valley and the mid-Atlantic today, making for hazardous travel conditions. NOAA noted that unseasonably cold temperatures more typical of January will prevail east of the Rocky Mountains for the next few days keeping winter around for a while longer. The clouds are associated with a cold front that stretched from eastern Maine through Maryland and west into the Tennessee Valley. At NASA/NOAA's GOES Project at NASA's Goddard Space Flight Center in Greenbelt, Md., the cloud data from NOAA's GOES-East satellite were overlaid on a true-color image of land and ocean created by data from the Moderate Resolution Imaging Spectroradiometer, or MODIS, instrument that flies aboard NASA's Aqua and Terra satellites. Together, those data created the entire picture of the position of this major winter storm. GOES satellites provide the kind of continuous monitoring necessary for intensive data analysis. Geostationary describes an orbit in which a satellite is always in the same position with respect to the rotating Earth. This allows GOES to hover continuously over one position on Earth's surface, appearing stationary. As a result, GOES provide a constant vigil for the atmospheric "triggers" for severe weather conditions such as tornadoes, flash floods, hail storms and hurricanes. For updated information about the storm system, visit NOAA's NWS website: www.weather.gov For more information about GOES satellites, visit: www.goes.noaa.gov/ or goes.gsfc.nasa.gov/ Rob Gutro NASA's Goddard Space Flight Center, Greenbelt, Md. NASA image use policy. NASA Goddard Space Flight Center enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission. Follow us on Twitter Like us on Facebook Find us on Instagram

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

Yan, Eugene; Pierce, Julia; Mahat, Vinod

This project is a part of the Regional Resiliency Assessment Program, led by the Department of Homeland Security, to address flooding hazards of regional significance for Portland, Maine. The pilot study was performed by Argonne National Laboratory to identify differences in spatial rainfall distributions between the radar-derived and rain-gauge rainfall datasets and to evaluate their impacts on urban flooding. The flooding impact analysis utilized a high-resolution 2-dimensional (2-D) hydrodynamic model (15 ft by 15 ft) incorporating the buildings, streets, stream channels, hydraulic structures, an existing city storm drain system, and assuming a storm surge along the coast coincident with amore » heavy rainfall event. Two historical storm events from April 16, 2007, and September 29, 2015, were selected for evaluation. The radar-derived rainfall data at a 200-m resolution provide spatially-varied rainfall patterns with a wide range of intensities for each event. The resultant maximum flood depth using data from a single rain gauge within the study area could be off (either under- or over-estimated) by more than 10% in the 2007 storm and more than 60% in the 2015 storm compared to the radar-derived rainfall data. The model results also suggest that the inundation area with a flow depth at or greater than 0.5 ft could reach 11% (2007 storm) and 17% (2015 storm) of the total study area, respectively. The lowland areas within the neighborhoods of North Deering, East Deering, East and West Baysides and northeastern Parkside, appear to be more vulnerable to the flood hazard in both storm events. The high-resolution 2-D hydrodynamic model with high-resolution radar-derived rainfall data provides an excellent tool for detailed urban flood analysis and vulnerability assessment. The model developed in this study could be potentially used to evaluate any proposed mitigation measures and optimize their effects in the future for Portland, ME.« less

Validation of a global satellite rainfall product for real time monitoring of meteorological extremes

NASA Astrophysics Data System (ADS)

Cánovas-García, Fulgencio; García-Galiano, Sandra; Karbalaee, Negar

2017-10-01

The real time monitoring of storms is important for the management and prevention of flood risks. However, in the southeast of Spain, it seems that the density of the rain gauge network may not be sufficient to adequately characterize the rainfall spatial distribution or the high rainfall intensities that are reached during storms. Satellite precipitation products such as PERSIANN-CCS (Precipitation Estimation from Remotely Sensed Information using Artificial Neural Networks - Cloud Classification System) could be used to complement the automatic rain gauge networks and so help solve this problem. However, the PERSIANN-CCS product has only recently become available, so its operational validity for areas such as south-eastern Spain is not yet known. In this work, a methodology for the hourly validation of PERSIANN-CCS is presented. We used the rain gauge stations of the SIAM (Sistema de Información Agraria de Murcia) network to study three storms with a very high return period. These storms hit the east and southeast of the Iberian Peninsula and resulted in the loss of human life, major damage to agricultural crops and a strong impact on many different types of infrastructure. The study area is the province of Murcia (Region of Murcia), located in the southeast of the Iberian Peninsula, covering an area of more than 11,000 km2 and with a population of almost 1.5 million. In order to validate the PERSIANN-CCS product for these three storms, contrasts were made with the hyetographs registered by the automatic rain gauges, analyzing statistics such as bias, mean square difference and Pearson's correlation coefficient. Although in some cases the temporal distribution of rainfall was well captured by PERSIANN-CCS, in several rain gauges high intensities were not properly represented. The differences were strongly correlated with the rain gauge precipitation, but not with satellite-obtained rainfall. The main conclusion concerns the need for specific local calibration for the study area if PERSIANN-CCS is to be used as an operational tool for the monitoring of extreme meteorological phenomena.

On the nature of rainfall in dry climate: Space-time patterns of convective rain cells over the Dead Sea region and their relations with synoptic state and flash flood generation

NASA Astrophysics Data System (ADS)

Belachsen, Idit; Marra, Francesco; Peleg, Nadav; Morin, Efrat

2017-04-01

Space-time patterns of rainfall are important climatic characteristics that influence runoff generation and flash flood magnitude. Their derivation requires high-resolution measurements to adequately represent the rainfall distribution, and is best provided by remote sensing tools. This need is further emphasized in dry climate regions, where rainfall is scarce and, often, local and highly variable. Our research is focused on understanding the nature of rainfall events in the dry Dead Sea region (Eastern Mediterranean) by identifying and characterizing the spatial structure and the dynamics of convective storm cores (known as rain cells). To do so, we take advantage of 25 years of corrected and gauge-adjusted weather radar data. A statistical analysis of convective rain-cells spatial and temporal characteristics was performed with respect to synoptic pattern, geographical location, and flash flood generation. Rain cells were extracted from radar data using a cell segmentation method and a tracking algorithm and were divided into rain events. A total of 10,500 rain cells, 2650 cell tracks and 424 rain events were elicited. Rain cell properties, such as mean areal and maximal rain intensity, area, life span, direction and speed, were derived. Rain events were clustered, according to several ERA-Interim atmospheric parameters, and associated with three main synoptic patterns: Cyprus Low, Low to the East of the study region and Active Red Sea Trough. The first two originate from the Mediterranean Sea, while the third is an extension of the African monsoon. On average, the convective rain cells in the region are 90 km2 in size, moving from West to East in 13 ms-1 and living 18 minutes. Several significant differences between rain cells of the various synoptic types were observed. In particular, Active Red Sea Trough rain cells are characterized by higher rain intensities and lower speeds, suggesting a higher flooding potential for small catchments. The north-south negative gradient of mean annual rainfall in the study region was found to be negatively correlated with rain cells intensity and positively correlated with rain cells area. Additional analysis was done for convective rain cells over two nearby catchments located in the central part of the study region, by ascribing some of the rain events to observed flash-flood events. It was found that rain events associated with flash-floods have higher maximal rain cell intensity and lower minimal cell speed than rain events that did not lead to a flash-flood in the watersheds. This information contributes to our understanding of rain patterns over the dry area of the Dead Sea and their connection to flash-floods. The statistical distributions of rain cells properties can be used for high space-time resolution stochastic simulations of rain storms that can serve as an input to hydrological models.

Earth Observations taken by the Expedition 18 Crew

NASA Image and Video Library

2009-01-30

ISS018-E-025705 (30 Jan. 2009) --- Betsiboka River floods in Madagascar are featured in this image photographed by an Expedition 18 crewmember on the International Space Station. Between Jan. 18-20, 2009, Tropical Storm Eric swept along the east coast of the island nation of Madagascar. Rain from this storm fell in the catchment of the Betsiboka River, one of the main rivers in northern Madagascar. In an unlikely coincidence, a larger storm, Cyclone Fanele crossed central Madagascar the next day on Jan. 21, with its outer bands dropping more rain in the Betsiboka basin. By the time this image was taken on the Jan. 30, the river was flooding all along its length.

Subtropical Storm Andrea

NASA Technical Reports Server (NTRS)

2007-01-01

The circling clouds of an intense low-pressure system sat off the southeast coast of the United States on May 8, 2007, when the Moderate Resolution Imaging Spectroradiometer (MODIS) on NASA's Terra satellite captured this image. By the following morning, the storm developed enough to be classified as a subtropical storm, a storm that forms outside of the tropics, but has many of the characteristics--hurricane-force winds, driving rains, low pressure, and sometimes an eye--of a tropical storm. Although it arrived several weeks shy of the official start of the hurricane season (June 1), Subtropical Storm Andrea became the first named storm of the 2007 Atlantic hurricane season. The storm has the circular shape of a tropical cyclone in this image, but lacks the tight organization seen in more powerful storms. By May 9, the storm's winds reached 75 kilometers per hour (45 miles per hour), and the storm was not predicted to get any stronger, said the National Hurricane Center. Though Subtropical Storm Andrea was expected to remain offshore, its strong winds and high waves pummeled coastal states, prompting a tropical storm watch. The winds fueled wild fires (marked with red boxes) in Georgia and Florida. The wind-driven flames generated thick plumes of smoke that concentrated in a gray-brown mass over Tampa Bay, Florida. Unfortunately for Georgia and Florida, which are experiencing moderate to severe drought, Subtropical Storm Andrea was not predicted to bring significant rain to the region right away, according to reports on the Washington Post Website.

Rain from Tropical Storm Noel

NASA Technical Reports Server (NTRS)

2007-01-01

Though not the most powerful storm of the 2007 Atlantic Hurricane season, Tropical Storm Noel was among the most deadly. Only Category 5 Hurricane Felix and its associated flooding had a higher toll. The slow-moving Tropical Storm Noel inundated the Dominican Republic, Haiti, Jamaica, Cuba, and the Bahamas with heavy rain between October 28 and November 1, 2007. The resulting floods and mudslides left at least 115 dead and thousands homeless throughout the Caribbean, reported the Associated Press on November 2, 2007. This image shows the distribution of the rainfall that made Noel a deadly storm. The image shows rainfall totals as measured by the Multi-satellite Precipitation Analysis (MPA) at NASA Goddard Space Flight Center from October 26 through November 1, 2007. The analysis is based on measurements taken by the Tropical Rainfall Measuring Mission (TRMM) satellite. The heaviest rainfall fell in the Dominican Republic and the Bahamas, northeast of Noel's center. Areas of dark red show that rainfall totals over the south-central Dominican Republic and parts of the Bahamas were over 551 millimeters (21 inches). Much of eastern Hispaniola, including both the Dominican Republic and Haiti received at least 200 mm (about 8 inches) of rain, shown in yellow. Rainfall totals over Haiti and Cuba were less, with a range of at least 50 mm (2 inches) to over 200 mm (8 inches).

The Microphysical Structure of Extreme Precipitation as Inferred from Ground-Based Raindrop Spectra.

NASA Astrophysics Data System (ADS)

Uijlenhoet, Remko; Smith, James A.; Steiner, Matthias

2003-05-01

The controls on the variability of raindrop size distributions in extreme rainfall and the associated radar reflectivity-rain rate relationships are studied using a scaling-law formalism for the description of raindrop size distributions and their properties. This scaling-law formalism enables a separation of the effects of changes in the scale of the raindrop size distribution from those in its shape. Parameters controlling the scale and shape of the scaled raindrop size distribution may be related to the microphysical processes generating extreme rainfall. A global scaling analysis of raindrop size distributions corresponding to rain rates exceeding 100 mm h1, collected during the 1950s with the Illinois State Water Survey raindrop camera in Miami, Florida, reveals that extreme rain rates tend to be associated with conditions in which the variability of the raindrop size distribution is strongly number controlled (i.e., characteristic drop sizes are roughly constant). This means that changes in properties of raindrop size distributions in extreme rainfall are largely produced by varying raindrop concentrations. As a result, rainfall integral variables (such as radar reflectivity and rain rate) are roughly proportional to each other, which is consistent with the concept of the so-called equilibrium raindrop size distribution and has profound implications for radar measurement of extreme rainfall. A time series analysis for two contrasting extreme rainfall events supports the hypothesis that the variability of raindrop size distributions for extreme rain rates is strongly number controlled. However, this analysis also reveals that the actual shapes of the (measured and scaled) spectra may differ significantly from storm to storm. This implies that the exponents of power-law radar reflectivity-rain rate relationships may be similar, and close to unity, for different extreme rainfall events, but their prefactors may differ substantially. Consequently, there is no unique radar reflectivity-rain rate relationship for extreme rain rates, but the variability is essentially reduced to one free parameter (i.e., the prefactor). It is suggested that this free parameter may be estimated on the basis of differential reflectivity measurements in extreme rainfall.

Rain Floods Central Texas

NASA Image and Video Library

2007-06-28

This image was taken on June 26, 2007, UTC 20:00. In this image an obvious storm hangs over the middle of the United States. Figure 1 shows NASA CloudSat data looking, in profile, at the cloud in this storm.

Extreme Wind, Rain, Storm Surge, and Flooding: Why Hurricane Impacts are Difficult to Forecast?

NASA Astrophysics Data System (ADS)

Chen, S. S.

2017-12-01

The 2017 hurricane season is estimated as one of the costliest in the U.S. history. The damage and devastation caused by Hurricane Harvey in Houston, Irma in Florida, and Maria in Puerto Rico are distinctly different in nature. The complexity of hurricane impacts from extreme wind, rain, storm surge, and flooding presents a major challenge in hurricane forecasting. A detailed comparison of the storm impacts from Harvey, Irma, and Maria will be presented using observations and state-of-the-art new generation coupled atmosphere-wave-ocean hurricane forecast model. The author will also provide an overview on what we can expect in terms of advancement in science and technology that can help improve hurricane impact forecast in the near future.

Impacts of a Destructive and Well-Observed Cross-Country Winter Storm.

NASA Astrophysics Data System (ADS)

Martner, Brooks E.; Rauber, Robert M.; Ramamurthy, Mohan K.; Rasmussen, Roy M.; Prater, Erwin T.

1992-02-01

A winter storm that crossed the continental United States in mid-February 1990 produced hazardous weather across a vast area of the nation. A wide range of severe weather was reported, including heavy snowfall; freezing rain and drizzle; thunderstorms with destructive winds, lightning, large hail, and tornadoes; prolonged heavy rain with subsequent flooding; frost damage to citrus orchards; and sustained destructive winds not associated with thunderstorms. Low-end preliminary estimates of impacts included 9 deaths, 27 injuries, and $120 million of property damage. At least 35 states and southeastern Canada were adversely affected. The storm occurred during the field operations of four independent atmospheric research projects that obtained special, detailed observations of it from the Rocky Mountains to the eastern great Lakes.

Metals and bacteria partitioning to various size particles in Ballona Creek storm water runoff.

PubMed

Brown, Jeffrey S; Stein, Eric D; Ackerman, Drew; Dorsey, John H; Lyon, Jessica; Carter, Patrick M

2013-02-01

Many storm water best management practice (BMP) devices function primarily by capturing particulate matter to take advantage of the well-documented association between storm water particles and pollutants. The hydrodynamic separation or settling methods used by most BMP devices are most effective at capturing medium to large particles; however, these may not be the most predominant particles associated with urban runoff. The present study examined particle size distribution in storm water runoff from an urban watershed in southern California and investigated the pollutant-particle associations of metals (Cu, Pb, Ni, and Zn) and bacteria (enterococci and Escherichia coli). During small storm events (≤0.7 cm rain), the highest concentration of pollutants were associated with a <6-µm filter fraction, which accounted for 70% of the per storm contaminant mass but made up more than 20% of the total particle mass. The pollutant-particle association changed with storm size. Most pollutant mass was associated with >35 µm size particles during a 5-cm rain event. These results suggest that much of the contaminant load in storm water runoff will not be captured by the most commonly used BMP devices, because most of these devices (e.g., hydrodynamic separators) are unable to capture particles smaller than 75 µm. Copyright © 2012 SETAC.

Storm impacts upon the composition of organic matrices in Nagara River--a study based on molecular weight and activated carbon adsorbability.

PubMed

Li, Fusheng; Yuasa, Akira; Chiharada, Hajime; Matsui, Yoshihiko

2003-09-01

The impacts of a heavy storm of rain on the composition of natural organic matter (NOM) in Nagara River water were studied in terms of molecular weights (MWs) and activated carbon (AC) adsorbabilities using six water samples collected during a critical Typhoon weather condition. The composition in MWs was analyzed using a HPSEC system and that in adsorbabilities was characterized using parameters devised to reflect NOMs average adsorptive strength (K(M)), adsorptive strength polydispersity (sigma), affinity to AC (1/n) and non-adsorbable fraction (C(non)/C(T0)), respectively. These parameters were determined by model description of observed isotherms with a distributed fictive component method. The heavy storm of rain brought higher content of larger organic components into the river source, thus causing changes of NOMs weight-averaged MWs in the range of 2962-3495 Dalton and MW polydispersity in the narrow range of 1.153-1.226. Comparison of K(M) and sigma values for all samples assessed with both indices of TOC and UV260 showed that large proportions of the storm-induced organic components had adsorptive strengths similar to those existent before the storm, with the presence levels for components revealing much strong and weak adsorbabilities being low. Among all organic components brought into the river by the storm of rain, the percentages of non-adsorbable ones was lower (smaller C(non)/C(T0) values); and the adsorbable ones had generally more affinity to the adsorbents used (smaller 1/n values).

Structure of Highly Sheared Tropical Storm Chantal during CAMEX-4

NASA Technical Reports Server (NTRS)

Heymsfield, G. M.; Halverson, J.; Ritchie, E.; Simpson, Joanne; Molinari, J.; Tian, L.

2006-01-01

Tropical Storm Chantal during August 2001 was a storm that failed to intensify over the few days prior to making landfall on the Yucatan Peninsula. An observational study of Tropical Storm Chantal is presented using a diverse dataset including remote and in situ measurements from the NASA ER-2 and DC-8 and the NOAA WP-3D N42RF aircraft and satellite. The authors discuss the storm structure from the larger-scale environment down to the convective scale. Large vertical shear (850-200-hPa shear magnitude range 8-15 m/s) plays a very important role in preventing Chantal from intensifying. The storm had a poorly defined vortex that only extended up to 5-6-km altitude, and an adjacent intense convective region that comprised a mesoscale convective system (MCS). The entire low-level circulation center was in the rain-free western side of the storm, about 80 km to the west-southwest of the MCS. The MCS appears to have been primarily the result of intense convergence between large-scale, low-level easterly flow with embedded downdrafts, and the cyclonic vortex flow. The individual cells in the MCS such as cell 2 during the period of the observations were extremely intense, with reflectivity core diameters of 10 km and peak updrafts exceeding 20 m/s. Associated with this MCS were two broad subsidence (warm) regions, both of which had portions over the vortex. The first layer near 700 hPa was directly above the vortex and covered most of it. The second layer near 500 hPa was along the forward and right flanks of cell 2 and undercut the anvil divergence region above. There was not much resemblance of these subsidence layers to typical upper-level warm cores in hurricanes that are necessary to support strong surface winds and a low central pressure. The observations are compared to previous studies of weakly sheared storms and modeling studies of shear effects and intensification. The configuration of the convective updrafts, low-level circulation, and lack of vertical coherence between the upper- and lower-level warming regions likely inhibited intensification of Chantal. This configuration is consistent with modeled vortices in sheared environments, which suggest the strongest convection and rain in the downshear left quadrant of the storm, and subsidence in the upshear right quadrant. The vertical shear profile is, however, different from what was assumed in previous modeling in that the winds are strongest in the lowest levels and the deep tropospheric vertical shear is on the order of 10-12 m/s.

Is It Going to Rain Today? Understanding the Weather Forecast.

ERIC Educational Resources Information Center

Allsopp, Jim; And Others

1996-01-01

Presents a resource for science teachers to develop a better understanding of weather forecasts, including outlooks, watches, warnings, advisories, severe local storms, winter storms, floods, hurricanes, nonprecipitation hazards, precipitation probabilities, sky condition, and UV index. (MKR)

Radar characteristics of cloud-to-ground lightning producing storms in Florida

NASA Technical Reports Server (NTRS)

Buechler, D. E.; Goodman, S. J.

1991-01-01

The interrelation between cloud-to-ground lightning, convective rainfall, and the environment in Central Florida storms is examined. The rain flux, storm area, and ground discharge rates are computed within the outlined area. Time-height cross sections of maximum dBZ values at each level for two storms are shown. The multicellular nature of these storms is readily apparent. The cloud-to-ground lightning activity occurs mainly where high reflectivity values (30-40 dBZ) extend above 7 km.

Flood of January 1982 in the San Francisco Bay area, California

USGS Publications Warehouse

Blodgett, J.C.; Chin, E.H.

1989-01-01

A major winter storm originating over the Pacific Ocean moved through central California in early January 1982. As much as 16 inches of rain fell in Marin County and 25 inches in the mountains bordering Santa Cruz County. The storm of January 3-5, 1982 had a stable atmospheric structure, and the layer of moist maritime air was confined to altitudes between 50 and 700 ft; this phenomenon caused the rain to fall most heavily along the lower slopes of the coastal mountains. As a result of antecedent rainfall, streamflow in the San Francisco Bay area exceeded normal from the end of October to the end of December 1981. For most streams, the January 1982 flood was the largest since the flood of December 1955, but it was not significantly large in comparison with historic peak-flow data. Damages associated with the storm were substantial, but flooding from stream runoff was not the major problem. Greater than normal antecedent rainfall, together with the prolonged heavy rain, liquified the supersaturated soil cover and caused numerous slope failures and debris flows on steep, unstable slopes. The median recurrence interval of the 1982 peak for 66 streamflow-gaging stations in the San Francisco Bay area is 10 years; for the 1955 flood, the median recurrence interval for 16 stations is 11 years. Streams with highest unit peak runoff were in the Santa Cruz Mountains and North Bay subareas. Median recurrence intervals of flood volumes for durations of 1, 3, and 8 consecutive days during the January 1982 flood are 18, 11, and 8; these recurrence intervals are comparable to those of the December 1955 flood, which are 13 , 16, and 14 years. (USGS)

Rain volume estimation over areas using satellite and radar data

NASA Technical Reports Server (NTRS)

Doneaud, Andre A.; Vonderhaar, T. H.; Johnson, L. R.; Laybe, P.; Reinke, D.

1987-01-01

The analysis of 18 convective clusters demonstrates that the extension of the Area-Time-Integral (ATI) technique to the use of satellite data is possible. The differences of the internal structures of the radar reflectivity features, and of the satellite features, give rise to differences in estimating rain volumes by delineating area; however, by focusing upon the area integrated over the lifetime of the storm, it is suggested that some of the errors produced by the differences in the cloud geometries as viewed by radar or satellite are minimized. The results are good and future developments should consider data from different climatic regions and should allow for implementation of the technique in a general circulation model.

Footprints of storms on the sea: A view from spaceborne synthetic aperture radar

NASA Technical Reports Server (NTRS)

Atlas, David

1994-01-01

Synthetic aperture radar (SAR) on board Seasat observed images of stormlike echoes on the sea in 1978. The core of these images is usually an echo-free hole which is attributed to the damping of the short (30-cm) radar detectable gravity waves by the intense rain in the storm core. Although 'the beating down of waves by rain' is consistent with observations by seafarers and with the first scientific explanation of the phenomenon by Reynolds (1875), neither theory nor experiment has provided definitive support. One experiment appears to provide the key; it shows that the kenetic energy of the rain produces sufficient turbulence in a thin fresh water layer to damp 30-cm waves in 10-20 s, thus producing the echo-free hole. A sequence of positive feedbacks then serves to damp the longer waves. The angular dependence of the sea surface echo cross sections seen by Seasat SAR outside the echo-free hole indicates winds diverging from the downdraft induced by the intense rain core. The wind-generated waves and associated echoes extend out to a sharply defined gust front. The sea surface footprint thus mimics the features of a storm microburst. The variations in surface radar cross section due to a combination of rain and wind effects impacts spaceborne measurements of surface winds by scatterometry and rainfall measurements by radar. Portions of this synthesis remain speculative but serve as hypotheses for further research.

Impacts of heavy rain and typhoon on allergic disease.

PubMed

Park, Kwan Jun; Moon, Jong Youn; Ha, Jong Sik; Kim, Sun Duk; Pyun, Bok Yang; Min, Taek Ki; Park, Yoon Hyung

2013-06-01

Allergic disease may be increased by climate change. Recent reports have shown that typhoon and heavy rain increase allergic disease locally by concentration of airborne allergens of pollen, ozone, and fungus, which are causes of allergic disease. The objective of this study was to determine whether typhoon and heavy rain increase allergic disease in Korea. This study included allergic disease patients of the area declared as a special disaster zone due to storms and heavy rains from 2003 to 2009. The study used information from the Korea Meteorological Administration, and from the National Health Insurance Service for allergic diseases (asthma, allergic rhinitis, and atopic dermatitis). During a storm period, the numbers of allergy rhinitis and atopic dermatitis outpatients increased [rate ratio (RR) = 1.191; range, 1.150-1.232] on the sixth lag day. However, the number of asthma outpatients decreased (RR = 0.900; range, 0.862-0.937) on the sixth lag day after a disaster period. During a storm period, the numbers of allergic rhinitis outpatients (RR = 1.075; range, 1.018-1.132) and atopy outpatients increased (RR = 1.134; range, 1.113-1.155) on the seventh lag day. However, the number of asthma outpatients decreased to RR value of 0.968 (range, 0.902-1.035) on the fifth lag day. This study suggests that typhoon and heavy rain increase allergic disease apart from asthma. More study is needed to explain the decrease in asthma.

Climatological Characterization of Three-Dimensional Storm Structure from Operational Radar and Rain Gauge Data.

NASA Astrophysics Data System (ADS)

Steiner, Matthias; Houze, Robert A., Jr.; Yuter, Sandra E.

1995-09-01

Three algorithms extract information on precipitation type, structure, and amount from operational radar and rain gauge data. Tests on one month of data from one site show that the algorithms perform accurately and provide products that characterize the essential features of the precipitation climatology. Input to the algorithms are the operationally executed volume scans of a radar and the data from a surrounding rain gauge network. The algorithms separate the radar echoes into convective and stratiform regions, statistically summarize the vertical structure of the radar echoes, and determine precipitation rates and amounts on high spatial resolution.The convective and stratiform regions are separated on the basis of the intensity and sharpness of the peaks of echo intensity. The peaks indicate the centers of the convective region. Precipitation not identified as convective is stratiform. This method avoids the problem of underestimating the stratiform precipitation. The separation criteria are applied in exactly the same way throughout the observational domain and the product generated by the algorithm can be compared directly to model output. An independent test of the algorithm on data for which high-resolution dual-Doppler observations are available shows that the convective stratiform separation algorithm is consistent with the physical definitions of convective and stratiform precipitation.The vertical structure algorithm presents the frequency distribution of radar reflectivity as a function of height and thus summarizes in a single plot the vertical structure of all the radar echoes observed during a month (or any other time period). Separate plots reveal the essential differences in structure between the convective and stratiform echoes.Tests yield similar results (within less than 10%) for monthly rain statistics regardless of the technique used for estimating the precipitation, as long as the radar reflectivity values are adjusted to agree with monthly rain gauge data. It makes little difference whether the adjustment is by monthly mean rates or percentiles. Further tests show that 1-h sampling is sufficient to obtain an accurate estimate of monthly rain statistics.

Flood Damage Assessment in Pearl River Delta Rural Area Application in Huashan Town, Huadu District,Guanghzou during the 2017 5.7 Heavy Rain Storm

NASA Astrophysics Data System (ADS)

Wang, X.

2017-12-01

The Pearl River Delta (PRD) in China, the summer rain storm occurs frequently, the flood damage is very serious. Damage assessment is the basis of scientific decision-making in disaster mitigation. All approaches of flood damage analysis contain uncertainties due to the inaccuracies and generalisations used, the lack of data aggravates this problem, making methods very rough. This study presents a detailed flood damage assessment framework in Pearl River Delta rural area, using 2017 "5.7" heavy rain storm event to simulate the process and estimate the flood loss in resident building and property, agriculture production. The framework integrates four modules,1) utilize the remote sensing and statistical yearbook and so on to construct the disaster bearing bodies GIS database; 2) using hydraulics model to simulate the flood extent and depth spatial distribution;3)through field investigation to obtain the flood loss data for all kinds of hazard-affected body, using statistical analysis method to get the damage curves;4)Integrate flood scenarios, disaster bearing bodies GIS database and damage curves to calculate the flood loss estimation value. Using this methodology, in the 2017 "5.7" heavy rain storm event, Huashan Town flood damage loss is underestimate compared with the government report, because of not considering the damage of water conservancy facilities. But the disaster loss value on the spatial distribution is consistent with actual situation. In terms of aggregated values in the whole town, the model is capable of obtaining figures that are within the same order of magnitude. This study produce a flood damage assessment framework taking into account the regional characteristics of PRD rural area, provide a template for future practice. This study only considers the current impacts, the framework should be improved by taking into account socio-economic and climatic changes, as well as implementing adaptation measures to be applied to assess the potential future damages. Key words: Heavy rain storm; flood; damage assessment; Pearl River Delta; rural area

Analysis of SFMR-Derived and Satellite-Based Rain Rates over the Tropical Western North Pacific

DTIC Science & Technology

2010-03-01

from SFMR are compared to rain rates from the Advanced Microwave Scanning Radiometer–EOS ( ASMR -E) and the Tropical Rainfall Measuring Mission (TRMM...2010 program. Rain rates from SFMR are compared to rain rates from the Advanced Microwave Scanning Radiometer–EOS ( ASMR -E) and the Tropical Rainfall...Figures 10 and 11, except for the ASMR -E and (a) earth-relative flight track and (b) storm-relative flight track for TY Sinlaku on 12 Sep 2008

High-Resolution Rainfall From Radar Reflectivity and Terrestrial Rain Gages for use in Estimating Debris-Flow Susceptibility in the Day Fire, California

NASA Astrophysics Data System (ADS)

Hanshaw, M. N.; Schmidt, K. M.; Jorgensen, D. P.; Stock, J. D.

2007-12-01

Constraining the distribution of rainfall is essential to evaluating the post-fire mass-wasting response of steep soil-mantled landscapes. As part of a pilot early-warning project for flash floods and debris flows, NOAA deployed a portable truck-mounted Shared Mobile Atmospheric Research and Teaching Radar (SMART-R) to the 2006 Day fire in the Transverse Ranges of Southern California. In conjunction with a dense array of ground- based instruments, including 8 tipping-bucket rain gages located within an area of 170 km2, this C-band mobile Doppler radar provided 200-m grid cell estimates of precipitation data at fine temporal and spatial scales in burned steeplands at risk from hazardous flash floods and debris flows. To assess the utility of using this data in process models for flood and debris flow initiation, we converted grids of radar reflectivity to hourly time-steps of precipitation using an empirical relationship for convective storms, sampling the radar data at the locations of each rain gage as determined by GPS. The SMART-R was located 14 km from the farthest rain gage, but <10 km away from our intensive research area, where 5 gages are located within <1-2 km of each other. Analyses of the nine storms imaged by radar throughout the 2006/2007 winter produced similar cumulative rainfall totals between the gages and their SMART-R grid location over the entire season which correlate well on the high side, with gages recording the most precipitation agreeing to within 11% of the SMART-R. In contrast, on the low rainfall side, totals between the two recording systems are more variable, with a 62% variance between the minimums. In addition, at the scale of individual storms, a correlation between ground-based rainfall measurements and radar-based rainfall estimates is less evident, with storm totals between the gages and the SMART-R varying between 7 and 88%, a possible result of these being relatively small, fast-moving storms in an unusually dry winter. The SMART-R also recorded higher seasonal cumulative rainfall than the terrestrial gages, perhaps indicating that not all precipitation reached the ground. For one storm in particular, time-lapse photographs of the ground document snow. This could explain, in part, the discrepancy between storm-specific totals when the rain gages recorded significantly lower totals than the SMART-R. For example, during the storm where snow was observed, the SMART-R recorded a maximum of 66% higher rainfall than the maximum recorded by the gages. Unexpectedly, the highest elevation gage, located in a pre-fire coniferous vegetation community, consistently recorded the lowest precipitation, whereas gages in the lower elevation pre- fire chaparral community recorded the highest totals. The spatial locations of the maximum rainfall inferred by the SMART-R and the terrestrial gages are also offset by 1.6 km, with terrestrial values shifted easterly. The observation that the SMART-R images high rainfall intensities recorded by rain gages suggests that this technology has the ability to quantitatively estimate the spatial distribution over larger areas at a high resolution. Discrepancies on the storm scale, however, need to be investigated further, but we are optimistic that such high resolution data from the SMART-R and the terrestrial gages may lead to the effective application of a prototype debris-flow warning system where such processes put lives at risk.

Use of METEOSAT images for Tracking Severe Weather Conditions: Application to the Extreme Event of 24 October 2007 in Rio de Janeiro

NASA Astrophysics Data System (ADS)

Barbosa, Humberto

Previous studies on severe storms and related flash foods over large urban areas of Southeastern Brazil have proceeded through the analyses of specific individual case studies. These urban areas, especially in austral summer, are prone to severe convective rainfall that affects targets that are difficult to protect, such as vulnerable communities. The synoptic case on 24 October 2007 showed severe thunderstorms with heavy rains produced widespread street flooding and major damage across the Rio de Janeiro metropolitan area and surrounding locations. The suspected cause determining heavy rains were associated with the intrusion of the cold front towards this urban area, and the interaction that occurred between it and the tropical moist air mass moved from the Amazon deep convection. In this context, METEOSAT Second Generation is an important tool to monitoring the dynamical evolution of cloud structures. This event presented the need to explore possible applications of METEOSAT-9 image analyses in this particular location to account for the possibility of tracking the weather disturbances. One way of supporting the exploratory analyses was by applying the RGB air masses and IR 10.8 images. The results showed that both the RGB air masses and IR 10.8 analyses attain clear and good approach in monitoring and evaluating severe storms that can cause widespread daily rains over the large urban areas located at Southeastern Brazil.

The Shepherd Creek experience and some lessons learned

EPA Science Inventory

A decentralized, retrofit approach to storm water management was implemented in a small suburban drainage on the basis of a voluntary reverse auction. This campaign led to the installation of 83 rain gardens and 176 rain barrels on approximately 20 percent of 350 residential prop...

[Relationship Between Core Convective Structure and Intensity Change in Tropical Cyclones]. [Structure of the HighIy Sheared Tropical Stom Chantal During CAMEX-4

NASA Technical Reports Server (NTRS)

2004-01-01

Tropical Storm Chantal during August 2001 was a storm that failed to intensify over the few days prior to making landfall on the Yucatan Peninsula. An observational study of Tropical Storm Chantal is presented using a diverse data set including remote and in situ measurements from the NASA ER-2 and DC-8 and the NOAA WP-3D N42RF aircraft and satellite data. The authors discuss the storm structure from the larger scale environment down to the convective scale. Large vertical shear (850-200 hPa shear magnitude range 8-15 m/s) plays a very important role in preventing Chantal from intensifying. The storm had a poorly defined vortex that only extended up to 5-6 km altitude, and an adjacent intense convective region that comprised an Mesoscale Convective System (MCS). The entire low-level circulation center was in the rain-free western side of the storm, about 80 km to the west-southwest of the MCS. The MCS appears to have been primarily the result of intense convergence between large scale, low-level easterly flow with embedded downdrafts, and the cyclonic vortex flow. The individual cells in the MCS such as Cell 2 during the period of the observations, were extremely intense with reflectivity core diameters of 10 km and peak updrafts exceeding 20 m/s. Associated with this MCS were two broad subsidence (warm) regions both of which had portions over the vortex. The first layer near 700 hPa was directly above the vortex and covered most of it. The second layer near 500 hPa was along the forward and right flanks of Cell 2 and undercut the anvil divergence region above. There was not much resemblance of these subsidence layers to typical upper level warm cores in hurricanes that are necessary to support strong surface winds and a low central pressure. The observations are compared to previous studies of weakly sheared storms and modeling studies of shear effects and intensification. The configuration of the convective updrafts, low-level circulation, and lack of vertical coherence between the upper and low level warming regions, likely inhibited intensification of Chantal. This configuration is consistent with modeling of vortices in sheared environments, which suggest strongest convection and rain in the downshear left quadrant of the storm, and subsidence in the upshear right quadrant. The vertical shear profile is however different from what was assumed in previous modeling in that the winds are strongest in the lowest levels and the deep tropospheric vertical shear is on the order of 10-12 m/s.

Microwave Observations of Precipitation and the Atmosphere

NASA Technical Reports Server (NTRS)

Staelin, David H.; Rosenkranz, Philip W.

2004-01-01

This research effort had three elements devoted to improving satellite-derived passive microwave retrievals of precipitation rate: morphological rain-rate retrievals, warm rain retrievals, and extension of a study of geostationary satellite options. The morphological precipitation-rate retrieval method uses for the first time the morphological character of the observed storm microwave spectra. The basic concept involves: 1) retrieval of point rainfall rates using current algorithms, 2) using spatial feature vectors of the observations over segmented multi-pixel storms to estimate the integrated rainfall rate for that storm (cu m/s), and 3) normalization of the point rain-rate retrievals to ensure consistency with the storm-wide retrieval. This work is ongoing, but two key steps have been completed: development of a segmentation algorithm for defining spatial regions corresponding to single storms for purposes of estimation, and reduction of some of the data from NAST-M that will be used to support this research going forward. The warm rain retrieval method involved extension of Aquai/AIRS/AMSU/HSB algorithmic work on cloud water retrievals. The central concept involves the fact that passive microwave cloud water retrievals over approx. 0.4 mm are very likely associated with precipitation. Since glaciated precipitation is generally detected quite successfully using scattering signatures evident in the surface-blind 54- and 183-GHz bands, this new method complements the first by permitting precipitation retrievals of non-glaciated events. The method is most successful over ocean, but has detected non-glaciated convective cells over land, perhaps in their early formative stages. This work will require additional exploration and validation prior to publication. Passive microwave instrument configurations for use in geostationary orbit were studied. They employ parabolic reflectors between 2 and 4 meters in diameter, and frequencies up to approx.430 GHz; this corresponds to nadir spot diameters as small as 10 km.

Sustainable Landscape Systems for Managing Storm Water 2nd Edition

EPA Science Inventory

Rain gardens are designed to capture and infiltrate rainwater in the landscape. These gardens are also called "rain water gardens". Rainwater is routed to the garden and filtered naturally by the plants and soils in the garden. This filtration process removes nutrients and poll...

Not Out of Control: Analysis of the Federal Disaster Spending Trend

DTIC Science & Technology

2016-03-01

included heavy rain, excessive rainfall, tropical storms, hurricanes, flooding, coastal flooding, wind, straight line winds, high winds, tornadoes ...straight line winds, tornadoes , high winds, coastal flooding, soil saturation, and mud flow.174 Despite the high number of severe storm declarations over

Rain depolarization and attenuation measurements at 11.7, 19.04, and 28.56 GHz - A description of the experiment and some preliminary results

NASA Technical Reports Server (NTRS)

Bostian, C. W.; Holt, S. B., Jr.; Kauffman, S. R.; Manus, E. A.; Marshall, R. E.; Stuzman, W. L.; Wiley, P. H.

1977-01-01

The considered investigation made use of the Communications Technology Satellite (CTS) downlink and the beacons carried by the Comstar satellites. The general behavior of rain attenuation and depolarization is illustrated with the aid of data from a storm which took place on July 15, 1976. The effect of the rain on the copolarized signal is indicated in a graph. Another graph shows the behavior of the cross-polarized signal component. Phase effects are also considered together with statistical curves for attenuation. The considered data from CTS indicate that, at least during summer convective storms, attenuation at 11.7 GHz is much more severe than anticipated. Attenuation may be a more serious impediment to dual polarized satellite links at this frequency than is depolarization.

Impacts of Heavy Rain and Typhoon on Allergic Disease

PubMed Central

Park, Kwan Jun; Moon, Jong Youn; Ha, Jong Sik; Kim, Sun Duk; Pyun, Bok Yang; Min, Taek Ki; Park, Yoon Hyung

2013-01-01

Objectives Allergic disease may be increased by climate change. Recent reports have shown that typhoon and heavy rain increase allergic disease locally by concentration of airborne allergens of pollen, ozone, and fungus, which are causes of allergic disease. The objective of this study was to determine whether typhoon and heavy rain increase allergic disease in Korea. Methods This study included allergic disease patients of the area declared as a special disaster zone due to storms and heavy rains from 2003 to 2009. The study used information from the Korea Meteorological Administration, and from the National Health Insurance Service for allergic diseases (asthma, allergic rhinitis, and atopic dermatitis). Results During a storm period, the numbers of allergy rhinitis and atopic dermatitis outpatients increased [rate ratio (RR) = 1.191; range, 1.150–1.232] on the sixth lag day. However, the number of asthma outpatients decreased (RR = 0.900; range, 0.862–0.937) on the sixth lag day after a disaster period. During a storm period, the numbers of allergic rhinitis outpatients (RR = 1.075; range, 1.018–1.132) and atopy outpatients increased (RR = 1.134; range, 1.113–1.155) on the seventh lag day. However, the number of asthma outpatients decreased to RR value of 0.968 (range, 0.902–1.035) on the fifth lag day. Conclusion This study suggests that typhoon and heavy rain increase allergic disease apart from asthma. More study is needed to explain the decrease in asthma. PMID:24159545

Hurricane Imaging Radiometer (HIRAD) Observations of Brightness Temperatures and Ocean Surface Wind Speed and Rain Rate During NASA's GRIP and HS3 Campaigns

NASA Technical Reports Server (NTRS)

Miller, Timothy L.; James, M. W.; Roberts, J. B.; Jones, W. L.; Biswas, S.; Ruf, C. S.; Uhlhorn, E. W.; Atlas, R.; Black, P.; Albers, C.

2012-01-01

HIRAD flew on high-altitude aircraft over Earl and Karl during NASA s GRIP (Genesis and Rapid Intensification Processes) campaign in August - September of 2010, and plans to fly over Atlantic tropical cyclones in September of 2012 as part of the Hurricane and Severe Storm Sentinel (HS3) mission. HIRAD is a new C-band radiometer using a synthetic thinned array radiometer (STAR) technology to obtain spatial resolution of approximately 2 km, out to roughly 30 km each side of nadir. By obtaining measurements of emissions at 4, 5, 6, and 6.6 GHz, observations of ocean surface wind speed and rain rate can be retrieved. The physical retrieval technique has been used for many years by precursor instruments, including the Stepped Frequency Microwave Radiometer (SFMR), which has been flying on the NOAA and USAF hurricane reconnaissance aircraft for several years to obtain observations within a single footprint at nadir angle. Results from the flights during the GRIP and HS3 campaigns will be shown, including images of brightness temperatures, wind speed, and rain rate. Comparisons will be made with observations from other instruments on the campaigns, for which HIRAD observations are either directly comparable or are complementary. Features such as storm eye and eye-wall, location of storm wind and rain maxima, and indications of dynamical features such as the merging of a weaker outer wind/rain maximum with the main vortex may be seen in the data. Potential impacts on operational ocean surface wind analyses and on numerical weather forecasts will also be discussed.

Use of clomipramine, alprazolam, and behavior modification for treatment of storm phobia in dogs.

PubMed

Crowell-Davis, Sharon L; Seibert, Lynne M; Sung, Wailani; Parthasarathy, Valli; Curtis, Terry M

2003-03-15

To evaluate use of clomipramine, alprazolam, and behavior modification for treatment of storm phobia in dogs. Prospective open clinical trial. 40 dogs with storm phobia. Dogs received clomipramine at a dosage of 2 mg/kg (0.9 mg/lb), PO, every 12 hours for 3 months; then 1 mg/kg (0.45 mg/lb), PO, every 12 hours for 2 weeks; then 0.5 mg/kg (0.23 mg/lb), PO, every 12 hours for 2 weeks. Alprazolam was given at a dosage of 0.02 mg/kg (0.009 mg/lb), PO, as needed 1 hour before anticipated storms and every 4 hours as needed. Desensitization and counter-conditioning were conducted at home by the caregiver with an audio simulation of storm sounds that had induced a fear response during evaluation. 30 of the 32 dogs that completed the study had a degree of improvement, as measured by caregivers' global assessment. Two caregivers considered the storm phobia to be resolved. Panting, pacing, trembling, remaining near the caregiver, hiding, excessive salivation, destructiveness, excessive vocalization, self-trauma, and inappropriate elimination all decreased significantly during treatment. Improvement was greater during true storms (rain, thunder, and lightning) than during rain only. Response to audio simulation did not change during treatment. Four months after the study, improvement was maintained. The combination of clomipramine, alprazolam, and behavior modification can be effective in decreasing or eliminating storm phobia. Improvement could not be evaluated by use of audio simulation of a storm.

Susceptibility of central hardwood trees to stem breakage due to ice glazing

Treesearch

KaDonna C. Randolph

2014-01-01

During January 26-28, 2009, a winter storm dropped a mix of rain, ice, and snow from Texas across the Ohio River Valley and into New England. The storm caused multiple fatalities and millions of dollars of property damage and was called "the biggest natural disaster in modern Kentucky history" (Brammer and Funk 2009: 13). The storm disturbed an estimated 2.4...

A statistical model of extreme storm rainfall

NASA Astrophysics Data System (ADS)

Smith, James A.; Karr, Alan F.

1990-02-01

A model of storm rainfall is developed for the central Appalachian region of the United States. The model represents the temporal occurrence of major storms and, for a given storm, the spatial distribution of storm rainfall. Spatial inhomogeneities of storm rainfall and temporal inhomogeneities of the storm occurrence process are explicitly represented. The model is used for estimating recurrence intervals of extreme storms. The parameter estimation procedure developed for the model is based on the substitution principle (method of moments) and requires data from a network of rain gages. The model is applied to a 5000 mi2 (12,950 km2) region in the Valley and Ridge Province of Virginia and West Virginia.

Quantity and quality of runoff reduction and recharge enhancement from constructed rain gardens and vegetated retention ponds in Austin, Texas

NASA Astrophysics Data System (ADS)

Eljuri, A. G.; Moffett, K. B.

2013-12-01

Rain gardens and retention ponds are intended to reduce storm water and pollutant runoff to rivers and streams, rain gardens by enhancing infiltration and retention ponds by promoting evaporation. The City of Austin, Texas is actively investing money and time into these storm water management solutions, but there are no data comparing their effectiveness. In particular, comparisons of rain gardens against control plots and new wetland-vegetated retention pond designs against traditional grassy pond designs are lacking. This study quantifies the quantity and quality of storm runoff to and from five sites: three engineered sites, two rain gardens receiving direct runoff from the same residential roof and a planted retention pond receiving municipal parking lot runoff, and two control sites, a mulched residential lawn receiving direct roof runoff and a grassy municipal retention pond receiving parking lot runoff. A locally installed rain gauge monitors precipitation rates and we collect and analyze rainwater chemistry. Each site is instrumented with bottles to collect direct runoff samples and suction lysimeters within and below the root zone, at 10 cm and 40 cm depth, from which to collect soil water. Soil moisture sensors at 5 cm, 25 cm, and 50 cm depth are used to monitor changes in soil moisture profiles over time. Evapotranspiration rates were determined using local meteorological data and stomatal conductance measurements at the sites. Infiltrometer tests, soil characterizations, and vegetation surveys were also conducted at each site. The soil at the rain gardens are highly mixed with pebbles at the top and become a more uniform soil towards the bottom of the root zone. This differs from the control site where the soil is uniform except for the thin layer of wood chips at the surface. The water samples were analyzed for pH, dissolved organic carbon (DOC), dissolved inorganic carbon (DIC), and cations (incl. cadmium, iron, zinc, and lead) and anions (incl. ammonia and nitrate). Samples of waters are taken immediately after rain events and soil moisture is taken both immediately after and two days after events. Austin summers experience fewer rainy days than the spring, fall, and winter, but summer storms are usually high-intensity and short-duration, increasing the potential for flooding. Seasonally, rainfall is somewhat more concentrated around May and October. We find that the negligible constituent concentrations of rainfall quickly become enriched in metals and nutrients from contact with impervious surfaces and that the presence of vegetation is critical, both as canopy over the surface, which promotes substantially higher nutrient levels in runoff (e.g., 1.45 ppm ammonia and 1.68 ppm nitrate under an overhanging tree compared to 0.57 ppm and 0.13 ppm not under the tree), and as plantings in the pond and gardens, which promote infiltration. These field data and a GIS study comparing different possible distributions of future rain gardens and vegetated retention ponds across the city provide much needed data and analysis to support decision making regarding these green storm water management solutions in central Texas.

Evaluate Hydrologic Response on Spatiotemporal Characteristics of Rainfall Using High Resolution Radar Rainfall Data and WRF-Hydro Model

NASA Astrophysics Data System (ADS)

Gao, S.; Fang, N. Z.

2017-12-01

A previously developed Dynamic Moving Storm (DMS) generator is a multivariate rainfall model simulating the complex nature of precipitation field: spatial variability, temporal variability, and storm movement. Previous effort by the authors has investigated the sensitivity of DMS parameters on corresponding hydrologic responses by using synthetic storms. In this study, the DMS generator has been upgraded to generate more realistic precipitation field. The dependence of hydrologic responses on rainfall features was investigated by dissecting the precipitation field into rain cells and modifying their spatio-temporal specification individually. To retrieve DMS parameters from radar rainfall data, rain cell segmentation and tracking algorithms were respectively developed and applied on high resolution radar rainfall data (1) to spatially determine the rain cells within individual radar image and (2) to temporally analyze their dynamic behavior. Statistics of DMS parameters were established by processing a long record of rainfall data (10 years) to keep the modification on real storms within the limit of regional climatology. Empirical distributions of the DMS parameters were calculated to reveal any preferential pattern and seasonality. Subsequently, the WRF-Hydro model forced by the remodeled and modified precipitation was used for hydrologic simulation. The study area was the Upper Trinity River Basin (UTRB) watershed, Texas; and two kinds of high resolution radar data i.e. the Next-Generation Radar (NEXRAD) level III Digital Hybrid Reflectivity (DHR) product and Multi-Radar Multi-Sensor (MRMS) precipitation rate product, were utilized to establish parameter statistics and to recreate/remodel historical events respectively. The results demonstrated that rainfall duration is a significant linkage between DMS parameters and their hydrologic impacts—any combination of spatiotemporal characteristics that keep rain cells longer over the catchment will produce higher peak discharge.

KSC-2011-2639

NASA Image and Video Library

2011-03-31

CAPE CANAVERAL, Fla. – A Bald Eagle takes advantage of a break in rain and perches on a tree at NASA's Kennedy Space Center in Florida. Severe storms associated with a frontal system are moving through Central Florida, producing strong winds, heavy rain, frequent lightning and even funnel clouds. Photo credit: NASA/Ben Smegelsky

Are there prospects for enhanced groundwater recharge via infiltration of urban stormwater runoff?

EPA Science Inventory

This presentation will cover the basics of what a storm water best management practices and focus on infiltration-type practices using the example of rain gardens. I will demonstrate how water moves through rain gardens with a simple hydrologic model and discuss ancillary benefit...

Effectiveness of a decentralized stormwater management program in the reduction of runoff volume

EPA Science Inventory

A decentralized, retrofit approach to storm water management was implemented in a small suburban drainage on the basis of a voluntary reverse auction. This effort led to the installation of 83 rain gardens and 176 rain barrels on approximately 20 percent of 350 residential proper...

Satellite Views Powerful Winter Storm Battering Mid-Atlantic and New England

NASA Image and Video Library

2014-02-13

The monster winter storm that brought icing to the U.S. southeast moved northward along the Eastern Seaboard and brought snow, sleet and rain from the Mid-Atlantic to New England on February 13. A new image from NOAA's GOES satellite showed clouds associated with the massive winter storm stretch from the U.S. southeast to the northeast. Data from NOAA's GOES-East satellite taken on Feb. 13 at 1455 UTC/9:45 a.m. EST were made into an image by NASA/NOAA's GOES Project at NASA's Goddard Space Flight Center in Greenbelt, Md. The clouds and fallen snow data from NOAA's GOES-East satellite were overlaid on a true-color image of land and ocean created by data from the Moderate Resolution Imaging Spectroradiometer or MODIS instrument that flies aboard NASA's Aqua and Terra satellites.The image showed that the clouds associated with the storm were blanketing much of the U.S. East Coast. At 3:11 a.m. EST, a surface map issued by the National Weather Service or NWS showed the storm's low pressure area was centered over eastern North Carolina. Since then, the low has continued to track north along the eastern seaboard. By 11 a.m. EST, precipitation from the storm was falling from South Carolina to Maine, according to National Weather Service radar. By 11 a.m. EST, the Washington, D.C. region snow and sleet totals ranged from 3" in far eastern Maryland to over 18" in the northern and western suburbs in Maryland and Virginia. NWS reported that snow, sleet and rain were still falling and more snow is expected as the back side of the low moves into the region. The New York City region remained under an NWS Winter Storm Warning until 6 a.m. on Friday, February 14 and the National Weather Service expects minor coastal impacts Thursday into Friday afternoon. New England was also being battered by the storm. At 10:56 a.m. EST, Barnstable, Mass. on Cape Cod was experiencing rain and winds gusting to 28 mph. An NWS wind advisory is in effect for Cape Cod until 7 p.m. EST. Further north, Portland, Maine was experiencing heavy snow with winds from the northeast at 6 mph. The National Weather Service in Gray, Maine noted "Significant snowfall is likely for much of western Maine and New Hampshire as this storm passes by. There will be a mix or changeover to sleet and freezing rain over southern and coastal sections tonight...before all areas end as a period of snow Friday (Feb. 14) morning." On February 13 at 10 a.m. EST, NOAA's National Weather Service noted "An abundance of Atlantic moisture getting wrapped into the storm will continue to fuel widespread precipitation...which should lift through the Mid-Atlantic States and Northeast Thursday into Friday. A wide swath of heavy snow accumulations are expected with this storm...but air [moving] off the warmer ocean water should change snow over to rain along the coastal areas. Also...a narrow axis of sleet and freezing rain will be possible within the transition zone...which is expected to set up near the I-95 corridor." For updates on local forecasts, watches and warnings, visit NOAA's www.weather.gov webpage. GOES satellites provide the kind of continuous monitoring necessary for intensive data analysis. Geostationary describes an orbit in which a satellite is always in the same position with respect to the rotating Earth. This allows GOES to hover continuously over one position on Earth's surface, appearing stationary. As a result, GOES provide a constant vigil for the atmospheric "triggers" for severe weather conditions such as tornadoes, flash floods, hail storms and hurricanes. For updated information about the storm system, visit NOAA's WPC website: www.hpc.ncep.noaa.gov/ For more information about GOES satellites, visit: www.goes.noaa.gov/ or goes.gsfc.nasa.gov/ Credit: NASA/GSFC/Jeff Schmaltz/MODIS Land Rapid Response Team NASA image use policy. NASA Goddard Space Flight Center enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission. Follow us on Twitter Like us on Facebook Find us on Instagram

Impact of TRMM and SSM/I Rainfall Assimilation on Global Analysis and QPF

NASA Technical Reports Server (NTRS)

Hou, Arthur; Zhang, Sara; Reale, Oreste

2002-01-01

Evaluation of QPF skills requires quantitatively accurate precipitation analyses. We show that assimilation of surface rain rates derived from the Tropical Rainfall Measuring Mission (TRMM) Microwave Imager and Special Sensor Microwave/Imager (SSM/I) improves quantitative precipitation estimates (QPE) and many aspects of global analyses. Short-range forecasts initialized with analyses with satellite rainfall data generally yield significantly higher QPF threat scores and better storm track predictions. These results were obtained using a variational procedure that minimizes the difference between the observed and model rain rates by correcting the moist physics tendency of the forecast model over a 6h assimilation window. In two case studies of Hurricanes Bonnie and Floyd, synoptic analysis shows that this procedure produces initial conditions with better-defined tropical storm features and stronger precipitation intensity associated with the storm.

A Bulk Microphysics Parameterization with Multiple Ice Precipitation Categories.

NASA Astrophysics Data System (ADS)

Straka, Jerry M.; Mansell, Edward R.

2005-04-01

A single-moment bulk microphysics scheme with multiple ice precipitation categories is described. It has 2 liquid hydrometeor categories (cloud droplets and rain) and 10 ice categories that are characterized by habit, size, and density—two ice crystal habits (column and plate), rimed cloud ice, snow (ice crystal aggregates), three categories of graupel with different densities and intercepts, frozen drops, small hail, and large hail. The concept of riming history is implemented for conversions among the graupel and frozen drops categories. The multiple precipitation ice categories allow a range of particle densities and fall velocities for simulating a variety of convective storms with minimal parameter tuning. The scheme is applied to two cases—an idealized continental multicell storm that demonstrates the ice precipitation process, and a small Florida maritime storm in which the warm rain process is important.

Millimeter wave propagation modeling of inhomogeneous rain media for satellite communications systems

NASA Technical Reports Server (NTRS)

Persinger, R. R.; Stutzman, W. L.

1978-01-01

A theoretical propagation model that represents the scattering properties of an inhomogeneous rain often found on a satellite communications link is presented. The model includes the scattering effects of an arbitrary distribution of particle type (rain or ice), particle shape, particle size, and particle orientation within a given rain cell. An associated rain propagation prediction program predicts attenuation, isolation and phase shift as a function of ground rain rate. A frequency independent synthetic storm algorithm is presented that models nonuniform rain rates present on a satellite link. Antenna effects are included along with a discussion of rain reciprocity. The model is verified using the latest available multiple frequency data from the CTS and COMSTAR satellites. The data covers a wide range of frequencies, elevation angles, and ground site locations.

Temporal pattern of toxicity in runoff from the Tijuana River Watershed.

PubMed

Gersberg, Richard M; Daft, Daniel; Yorkey, Darryl

2004-02-01

Samples were collected from the Tijuana River under both dry weather (baseflow) conditions and during wet weather, and tested for toxicity using Ceriodaphnia dubia tests. Toxicity of waters in the Tijuana River was generally low under baseflow conditions, but increased markedly during high flow runoff events. In order to determine the temporal pattern of toxicity during individual rain events, sequential grab samples were collected using an autosampler at 5-7 h intervals after the start of the rain event, and tested for acute toxicity. In all cases, peak toxicity values (ranging from 2.8 to 5.8TU) for each storm occurred within the first 1-2 h of initiation of the rain event, and were statistically higher (using the 95% CL) for each of the pre-storm base flow values. However, there was no statistically significant correlation (p<0.05) between flow rate and toxicity when all storm data was pooled. Additionally, we used toxicity identification evaluation (TIE) procedures to attempt to identify the classes of chemicals that account for this early storm toxicity. Solid phase extraction was the only treatment that showed consistent and significant (P<0.05) removal of toxicity. These TIEs, conducted on the most toxic sample of the river's flow during runoff events, suggest that non-polar organics may be responsible for such toxicity. The temporal pattern of toxicity, both during a given storm event and seasonally, indicates that wash-off from the watershed by rainfall may deplete the supply of toxicity available for wash-off in subsequent events, so that a clearly consistent relationship between flow and toxicity was not evident.

Evaluation of rainfall structure on hydrograph simulation: Comparison of radar and interpolated methods, a study case in a tropical catchment

NASA Astrophysics Data System (ADS)

Velasquez, N.; Ochoa, A.; Castillo, S.; Hoyos Ortiz, C. D.

2017-12-01

The skill of river discharge simulation using hydrological models strongly depends on the quality and spatio-temporal representativeness of precipitation during storm events. All precipitation measurement strategies have their own strengths and weaknesses that translate into discharge simulation uncertainties. Distributed hydrological models are based on evolving rainfall fields in the same time scale as the hydrological simulation. In general, rainfall measurements from a dense and well maintained rain gauge network provide a very good estimation of the total volume for each rainfall event, however, the spatial structure relies on interpolation strategies introducing considerable uncertainty in the simulation process. On the other hand, rainfall retrievals from radar reflectivity achieve a better spatial structure representation but with higher uncertainty in the surface precipitation intensity and volume depending on the vertical rainfall characteristics and radar scan strategy. To assess the impact of both rainfall measurement methodologies on hydrological simulations, and in particular the effects of the rainfall spatio-temporal variability, a numerical modeling experiment is proposed including the use of a novel QPE (Quantitative Precipitation Estimation) method based on disdrometer data in order to estimate surface rainfall from radar reflectivity. The experiment is based on the simulation of 84 storms, the hydrological simulations are carried out using radar QPE and two different interpolation methods (IDW and TIN), and the assessment of simulated peak flow. Results show significant rainfall differences between radar QPE and the interpolated fields, evidencing a poor representation of storms in the interpolated fields, which tend to miss the precise location of the intense precipitation cores, and to artificially generate rainfall in some areas of the catchment. Regarding streamflow modelling, the potential improvement achieved by using radar QPE depends on the density of the rain gauge network and its distribution relative to the precipitation events. The results for the 84 storms show a better model skill using radar QPE than the interpolated fields. Results using interpolated fields are highly affected by the dominant rainfall type and the basin scale.

Long-Range Lightning Products for Short Term Forecasting of Tropical Cyclogenesis

NASA Astrophysics Data System (ADS)

Businger, S.; Pessi, A.; Robinson, T.; Stolz, D.

2010-12-01

This paper will describe innovative graphical products derived in real time from long-range lightning data. The products have been designed to aid in short-term forecasting of tropical cyclone development for the Tropical Cyclone Structure Experiment 2010 (TCS10) held over the western Pacific Ocean from 17 August to 17 October 2010 and are available online at http://www.soest.hawaii.edu/cgi-bin/pacnet/tcs10.pl. The long-range lightning data are from Vaisala’s Global Lightning Data 360 (GLD360) network and include time, location, current strength, polarity, and data quality indication. The products currently provided in real time include i. Infrared satellite imagery overlaid with lighting flash locations, with color indication of current strength and polarity (shades of blue for negative to ground and red for positive to ground). ii. A 15x15 degree storm-centered tile of IR imagery overlaid with lightning data as in i). iii. A pseudo reflectivity product showing estimates of radar reflectivity based on lightning rate - rain rate conversion derived from TRMM and PacNet data. iv. A lightning history product that plots each hour of lightning flash locations in a different color for a 12-hour period. v. Graphs of lightning counts within 50 or 300 km radius, respectively, of the storm center vs storm central sea-level pressure. vi. A 2-D graphic showing storm core lightning density along the storm track. The first three products above can be looped to gain a better understanding of the evolution of the lightning and storm structure. Examples of the graphics and their utility will be demonstrated and discussed. Histogram of lightning counts within 50 km of the storm center and graph of storm central pressure as a function of time.

OHD/HL - Hurricane

Science.gov Websites

flooding. While storm surge is always a potential threat, more people have died from inland flooding in the 56 people who perished, 50 drowned due to inland flooding. Satellite image of Hurricane Floyd people drowned. Damages exceeded $750 million. Tropical Storm Claudette (1979) brought 45 inches of rain

Identification of independent storm events: Seasonal and spatial variability of times between storms in Alpine area

NASA Astrophysics Data System (ADS)

Iadanzaa, Carla; Rianna, Maura; Orlando, Dario; Ubertini, Lucio; Napolitano, Francesco

2013-10-01

The aim of the paper is the identification of rain events that trigger landslides through the use of an exponential method to separate stochastic independent events. This activity is carried out within the definition of empirical rainfall thresholds for debris flows and shallow landslides. The study area is the Trento district, which is located in the northeast zone of an Alpine area. The work evaluates the factors that affect the variability in space and time of the critical duration of each rain gauge, defined as the minimum dry period duration that separates two rainy periods that are stochastically independent.

The Weekend Effect for Precipitation Over Eastern U.S.: Evidence for Midweek Storm Intensification by Pollution

NASA Technical Reports Server (NTRS)

Bell, Thomas

2007-01-01

Every week the U.S. population carries out a climate-change experiment by varying their activities with the day of the week. It is well documented that pollution levels vary on a weekly basis. Particulate aerosol pollution is generally a maximum in the middle of the week and a minimum on weekends. It is also well known that aerosols can affect precipitation, although whether they suppress or enhance storm development depends on many factors. The Tropical Rainfall Measuring Mission (TRMM) satellite has provided evidence that rain statistics change with the day of the week over the southeast U.S. and neighboring waters during the summer months (JJA) of 1998-2005. There is a midweek increase in both rain area and intensity over land, and a midweek decrease over the nearby Atlantic and perhaps the Gulf of Mexico. Statistical tests suggest that the weekly variations are very unlikely to be due to the random behavior of weather. We will discuss the TRMM evidence. Wind data from model reanalysis, rain-gauge data, and TRMM radar data all appear to be consistent with the picture that aerosols are causing summertime storms to grow more vigorously and to produce more rainfall.

Animation of Tropical Storm Joaquin right before it intensified into a hurricane on September 29, 2015

NASA Image and Video Library

2017-12-08

-- Joaquin became a tropical storm Monday evening (EDT) midway between the Bahamas and Bermuda and has now formed into a hurricane, the 3rd of the season--the difference is Joaquin could impact the US East Coast. GPM captured Joaquin Tuesday, September 29th at 21:39 UTC (5:39 pm EDT) as the hurricane moved slowly towards the west-southwest about 400 miles east of the northwestern Bahamas. At the time, Joaquin had been battling northerly wind shear, which was impeding the storm's ability to strengthen. However, compared to earlier in the day, the system was beginning to gain the upper hand as the shear began to relax its grip. At the time of this data visualization, Joaquin's low-level center of circulation was located further within the cloud shield, and the rain area was beginning to wrap farther around the center on the eastern side of the storm while showing signs of increased banding and curvature, a sure sign that Joaquin's circulation was intensifying. GPM shows a large area of very intense rain with rain rates ranging from around 50 to 132 mm/hr (~2 to 5 inches, shown in red and magenta) just to the right of the center. This is a strong indication that large amounts of heat are being released into the storm's center, fueling its circulation and providing the means for its intensification. Associated with the area of intense rain is an area of tall convective towers, known as a convective burst, with tops reaching up to 16.3 km (shown in orange). These towers when located near the storm's core are a strong indication that the storm is poised to strengthen as they too reveal the release of heat into the storm. At the time this data was taken, the National Hurricane Center reported that Joaquin's maximum sustained winds had increased to 65 mph from 40 mph earlier in the day, making Joaquin a strong tropical storm but poised to become a hurricane, which occurred this morning at 8:00 am EDT. With the inhibiting wind shear expected to continue to diminish and the system moving over warm waters, the National Hurricane Center is forecasting Joaquin to intensify further, possibly into a major hurricane within the next few days. Credit: NASA's Scientific Visualization Studio Data provided by the joint NASA/JAXA GPM mission NASA image use policy. NASA Goddard Space Flight Center enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission. Follow us on Twitter Like us on Facebook Find us on Instagram

A Student-Centered Field Project Comparing NEXRAD and Rain Gauge Precipitation Values in Mountainous Terrain.

ERIC Educational Resources Information Center

Woltemade, Christopher J.; Stanitski-Martin, Diane

2002-01-01

Undergraduate students compared Next Generation Weather Radar (NEXRAD) estimates of storm total precipitation to measurements from a network of 20 rain gauges. Student researchers gained valuable experience in field data collection, global positioning systems (GPS), geographic information systems (GIS), Internet data access and downloading,…

KSC-2011-2648

NASA Image and Video Library

2011-03-31

CAPE CANAVERAL, Fla. – An osprey takes advantage of a break in rain and ventures out of its nest near the Press Site at NASA's Kennedy Space Center in Florida. Severe storms associated with a frontal system are moving through Central Florida, producing strong winds, heavy rain, frequent lightning and even funnel clouds. Photo credit: NASA/Ben Smegelsky

KSC-2011-2645

NASA Image and Video Library

2011-03-31

CAPE CANAVERAL, Fla. – An osprey takes advantage of a break in rain and peers out of its nest near the Press Site at NASA's Kennedy Space Center in Florida. Severe storms associated with a frontal system are moving through Central Florida, producing strong winds, heavy rain, frequent lightning and even funnel clouds. Photo credit: NASA/Ben Smegelsky

KSC-2011-2644

NASA Image and Video Library

2011-03-31

CAPE CANAVERAL, Fla. – An osprey takes advantage of a break in rain and perches on a pole near the Press Site at NASA's Kennedy Space Center in Florida. Severe storms associated with a frontal system are moving through Central Florida, producing strong winds, heavy rain, frequent lightning and even funnel clouds. Photo credit: NASA/Ben Smegelsky

Observations of C-Band Brightness Temperatures and Ocean Surface Wind Speed and Rain Rate from the Hurricane Imaging Radiometer (HIRAD) during GRIP and HS3

NASA Technical Reports Server (NTRS)

Miller, Timothy L.; James, M. W.; Roberts, J. B.; Jones, W. L.; Biswas, S.; Ruf, C. S.; Uhlhorn, E. W.; Atlas, R.; Black, P.; Albers, C.

2013-01-01

HIRAD flew on high-altitude aircraft over Earl and Karl during NASA s GRIP (Genesis and Rapid Intensification Processes) campaign in August - September of 2010, and at the time of this writing plans to fly over Atlantic tropical cyclones in September of 2012 as part of the Hurricane and Severe Storm Sentinel (HS3) mission. HIRAD is a new C-band radiometer using a synthetic thinned array radiometer (STAR) technology to obtain cross-track resolution of approximately 3 degrees, out to approximately 60 degrees to each side of nadir. By obtaining measurements of emissions at 4, 5, 6, and 6.6 GHz, observations of ocean surface wind speed and rain rate can be retrieved. This technique has been used for many years by precursor instruments, including the Stepped Frequency Microwave Radiometer (SFMR), which has been flying on the NOAA and USAF hurricane reconnaissance aircraft for several years to obtain observations within a single footprint at nadir angle. Results from the flights during the GRIP and HS3 campaigns will be shown, including images of brightness temperatures, wind speed, and rain rate. Comparisons will be made with observations from other instruments on the campaigns, for which HIRAD observations are either directly comparable or are complementary. Features such as storm eye and eye-wall, location of storm wind and rain maxima, and indications of dynamical features such as the merging of a weaker outer wind/rain maximum with the main vortex may be seen in the data. Potential impacts on operational ocean surface wind analyses and on numerical weather forecasts will also be discussed.

Modelling approach for the rainfall erosivity index in sub-humid urban areas in northern Algeria

NASA Astrophysics Data System (ADS)

Touaibia, I.; Abderrahmane Guenim, N.; Touaibia, B.

2014-09-01

This work presents an approach for storm water erosivity index modelling in the absence of measurement in an urban area, in a sub-humid climate. In torrential storms, floods, loaded with sediments, obstruct storm water drainage. With the aim of estimating the amount of sediment that can be deposited on a stretch of road, adjacent to the study area, the erosivity index is determined from a count of 744 rain showers recorded over a period of 19 years. The Universal Soil Loss Equation (USLE) of Wischmeier and Smith is applied, where only the index of erosivity is calculated; it is based on the intensity of the rain starting the process of erosion in the basin. Functional relations are required between this factor and the explanatory variables. A power type regression model is reached, making it possible to bring a decision-making aid in absences of measurements.

Moments of catchment storm area

NASA Technical Reports Server (NTRS)

Eagleson, P. S.; Wang, Q.

1985-01-01

The portion of a catchment covered by a stationary rainstorm is modeled by the common area of two overlapping circles. Given that rain occurs within the catchment and conditioned by fixed storm and catchment sizes, the first two moments of the distribution of the common area are derived from purely geometrical considerations. The variance of the wetted fraction is shown to peak when the catchment size is equal to the size of the predominant storm. The conditioning on storm size is removed by assuming a probability distribution based upon the observed fractal behavior of cloud and rainstorm areas.

Stormwater Pollution Prevention Plan (SWPPP) for Coal Storage Area Stabilization Project

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

Project and Design Engineering

2011-03-01

The scope of this project is to stabilize the abandoned coal storage area and redirect the storm water runoff from sanitary sewer system to the storm drain system. Currently, the existing storm water runoff is directed to a perimeter concrete drainage swale and collected in a containment basin. The collected water is then pumped to a treatment facility and after treatment, is discharged to the Y-12 sanitary sewer system. The existing drainage swale and collection basin along with silt fencing will be used during aggregate placement and grading to provide erosion and sediment control. Inlet protection will also be installedmore » around existing structures during the storm water diversion construction. This project scope will include the installation of a non-woven geotextile fabric and compacted mineral aggregate base (paving optional) to stabilize the site. The geotextile specifications are provided on the vendor cut sheets in Appendix B. The installation of a storm water collection/retention area will also be installed on the southern side of the site in accordance with EPA Technical Guidance on Implementing the Stormwater Runoff Requirements for federal Projects under Section 438 of the Energy Independence and Security Act. The total area to be disturbed is approximately 2.5 acres. The order of activities for this Stormwater Pollution Prevention Plan (SWPPP) will be: (1) post notice of coverage (NOC) in a prominent display near entrance of the site; (2) install rain gauge on site or contact Y-12 Plant Shift Superintendent daily for Met tower rain gauge readings; (3) install stabilized construction exit on site; (4) install silt fencing along perimeter as indicated on the attached site plan; (5) regrade site; (6) install geotextile fabric and compacted mineral aggregate base; (7) install catch basin inlet protection where required; (8) excavate and lower existing catch basin tops, re-grade and asphalt to drain; and (9) when all disturbed areas are re-stabilized, remove silt fencing and any other temporary erosion control.« less

Wildfire-induced initiation of debris flows in a steep bedrock landscape, San Gabriel Mountains, California

NASA Astrophysics Data System (ADS)

Ulizio, T. P.; Palucis, M. C.; Fuller, B. M.; Lamb, M. P.

2017-12-01

Steep, rocky landscapes often produce large sediment yields and increased debris flow activity following wildfire. There are two main hypotheses for debris flow initiation in burned regions during rain storms: (1) debris flows initiate from failure of the soil mantle on hillslopes where fire has destroyed root systems resulting in loss of soil strength, and (2) debris flows initiate in river channels that have been loaded by dry ravel following incineration of vegetation dams on hillslopes. To evaluate these hypotheses, we monitored a steep first-order catchment that burned in the 2016 Fish Canyon fire within the front range of the San Gabriel Mountains, CA. Following each post-fire storm, we measured the hillslope and channel topography using UAV imaging and structure-from-motion, and monitored activity during storm events with field cameras. Following the fire, but prior to the first storm event, most of the hillslopes were stripped to bedrock and 0.5 m of dry ravel had accumulated along the length of the channel. By using measurements of sediment storage behind vegetation in a nearby unburned catchment, but with a similar burn history, we found that much of the loose sediment in the channel can be attributed to dry ravel following incineration of vegetation dams. Throughout the rainy season, the catchment produced a series of debris flows that evacuated the accumulated dry ravel in the channel, exposed bedrock in the channel, and built a debris flow fan across a terrace that abuts the downstream end of the channel. Although later storms were larger, most sediment transport occurred during the first few storms, indicating that sediment supply can limit debris flow activity, and that larger storms do not necessarily produce larger debris flows. Our measurements of the volume of the newly formed debris flow fan approximately matches the volume of evacuated ravel from the channel, and we did not observe landslide scars on hillslopes. Together, these observations and mass-balance constraints support the model by which limited hillslope soil in steep rocky landscapes is destabilized as dry ravel following wildfire, leading to infilling of channels with relatively fine and loose sediment that subsequently fails, producing debris flows during rain storms.

Validation of TRMM Precipitation Radar Through Comparison of its Multi-Year Measurements to Ground-Based Radar

NASA Technical Reports Server (NTRS)

Liao, Liang; Meneghini, Robert

2010-01-01

A procedure to accurately resample spaceborne and ground-based radar data is described, and then applied to the measurements taken from the Tropical Rainfall Measuring Mission (TRMM) Precipitation Radar (PR) and the ground-based Weather Surveillance Radar-1988 Doppler (WSR-88D or WSR) for the validation of the PR measurements and estimates. Through comparisons with the well-calibrated, non-attenuated WSR at Melbourne, Florida for the period 1998-2007, the calibration of the Precipitation Radar (PR) aboard the TRMM satellite is checked using measurements near the storm top. Analysis of the results indicates that the PR, after taking into account differences in radar reflectivity factors between the PR and WSR, has a small positive bias of 0.8 dB relative to the WSR, implying a soundness of the PR calibration in view of the uncertainties involved in the comparisons. Comparisons between the PR and WSR reflectivities are also made near the surface for evaluation of the attenuation-correction procedures used in the PR algorithms. It is found that the PR attenuation is accurately corrected in stratiform rain but is underestimated in convective rain, particularly in heavy rain. Tests of the PR estimates of rainfall rate are conducted through comparisons in the overlap area between the TRMM overpass and WSR scan. Analyses of the data are made both on a conditional basis, in which the instantaneous rain rates are compared only at those pixels where both the PR and WSR detect rain, and an unconditional basis, in which the area-averaged rain rates are estimated independently for the PR and WSR. Results of the conditional rain comparisons show that the PR-derived rain is about 9% greater and 19% less than the WSR estimates for stratiform and convective storms, respectively. Overall, the PR tends to underestimate the conditional mean rain rate by 8% for all rain categories, a finding that conforms to the results of the area-averaged rain (unconditional) comparisons.

First flush of storm runoff pollution from an urban catchment in China.

PubMed

Li, Li-Qing; Yin, Cheng-Qing; He, Qing-Ci; Kong, Ling-Li

2007-01-01

Storm runoff pollution process was investigated in an urban catchment with an area of 1.3 km2 in Wuhan City of China. The results indicate that the pollutant concentration peaks preceded the flow peaks in all of 8 monitored storm events. The intervals between pollution peak and flow peak were shorter in the rain events with higher intensity in the initial period than those with lower intensity. The fractions of pollution load transported by the first 30% of runoff volume (FF30) were 52.2%-72.1% for total suspended solids (TSS), 53.0%-65.3% for chemical oxygen demand (COD), 40.4%-50.6% for total nitrogen (TN), and 45.8%-63.2% for total phosphorus (TP), respectively. Runoff pollution was positively related to non-raining days before the rainfall. Intercepting the first 30% of runoff volume can remove 62.4% of TSS load, 59.4% of COD load, 46.8% of TN load, and 54.1% of TP load, respectively, according to all the storm events. It is suggested that controlling the first flush is a critical measure in reduction of urban stormwater pollution.

Precipitation Cluster Distributions: Current Climate Storm Statistics and Projected Changes Under Global Warming

NASA Astrophysics Data System (ADS)

Quinn, Kevin Martin

The total amount of precipitation integrated across a precipitation cluster (contiguous precipitating grid cells exceeding a minimum rain rate) is a useful measure of the aggregate size of the disturbance, expressed as the rate of water mass lost or latent heat released, i.e. the power of the disturbance. Probability distributions of cluster power are examined during boreal summer (May-September) and winter (January-March) using satellite-retrieved rain rates from the Tropical Rainfall Measuring Mission (TRMM) 3B42 and Special Sensor Microwave Imager and Sounder (SSM/I and SSMIS) programs, model output from the High Resolution Atmospheric Model (HIRAM, roughly 0.25-0.5 0 resolution), seven 1-2° resolution members of the Coupled Model Intercomparison Project Phase 5 (CMIP5) experiment, and National Center for Atmospheric Research Large Ensemble (NCAR LENS). Spatial distributions of precipitation-weighted centroids are also investigated in observations (TRMM-3B42) and climate models during winter as a metric for changes in mid-latitude storm tracks. Observed probability distributions for both seasons are scale-free from the smallest clusters up to a cutoff scale at high cluster power, after which the probability density drops rapidly. When low rain rates are excluded by choosing a minimum rain rate threshold in defining clusters, the models accurately reproduce observed cluster power statistics and winter storm tracks. Changes in behavior in the tail of the distribution, above the cutoff, are important for impacts since these quantify the frequency of the most powerful storms. End-of-century cluster power distributions and storm track locations are investigated in these models under a "business as usual" global warming scenario. The probability of high cluster power events increases by end-of-century across all models, by up to an order of magnitude for the highest-power events for which statistics can be computed. For the three models in the suite with continuous time series of high resolution output, there is substantial variability on when these probability increases for the most powerful precipitation clusters become detectable, ranging from detectable within the observational period to statistically significant trends emerging only after 2050. A similar analysis of National Centers for Environmental Prediction (NCEP) Reanalysis 2 and SSM/I-SSMIS rain rate retrievals in the recent observational record does not yield reliable evidence of trends in high-power cluster probabilities at this time. Large impacts to mid-latitude storm tracks are projected over the West Coast and eastern North America, with no less than 8 of the 9 models examined showing large increases by end-of-century in the probability density of the most powerful storms, ranging up to a factor of 6.5 in the highest range bin for which historical statistics are computed. However, within these regional domains, there is considerable variation among models in pinpointing exactly where the largest increases will occur.

RainCube 6U CubeSat

NASA Image and Video Library

2018-05-17

The RainCube 6U CubeSat with fully-deployed antenna. RainCube, CubeRRT and TEMPEST-D are currently integrated aboard Orbital ATKs Cygnus spacecraft and are awaiting launch on an Antares rocket. After the CubeSats have arrived at the station, they will be deployed into low-Earth orbit and will begin their missions to test these new technologies useful for predicting weather, ensuring data quality, and helping researchers better understand storms. https://photojournal.jpl.nasa.gov/catalog/PIA22457

Seasonal and situational impacts on the effectiveness of a decentralized stormwater management program in the reduction of runoff volume (Cincinnati OH; USA)

EPA Science Inventory

A decentralized, retrofit approach to storm water management was implemented in a small suburban drainage on the basis of a voluntary reverse auction. This campaign led to the installation of 83 rain gardens and 176 rain barrels on approximately 20 percent of 350 residential prop...

KSC-2011-2643

NASA Image and Video Library

2011-03-31

CAPE CANAVERAL, Fla. – Rain soaked Launch Pad 39A at NASA's Kennedy Space Center in Florida, where space shuttle Endeavour is poised to launch on its final mission, STS-134, to the International Space Station. Severe storms associated with a frontal system are moving through Central Florida, producing strong winds, heavy rain, frequent lightning and even funnel clouds. Photo credit: NASA/Ben Smegelsky

KSC-2011-2642

NASA Image and Video Library

2011-03-31

CAPE CANAVERAL, Fla. – Rain pounds Launch Pad 39A at NASA's Kennedy Space Center in Florida, where space shuttle Endeavour is poised to launch on its final mission, STS-134, to the International Space Station. Severe storms associated with a frontal system are moving through Central Florida, producing strong winds, heavy rain, frequent lightning and even funnel clouds. Photo credit: NASA/Ben Smegelsky

Water flow pathway and the organic carbon discharge during rain storm events in a coniferous forested head watershed, Tokyo, central Japan

NASA Astrophysics Data System (ADS)

Moriizumi, Mihoko; Terajima, Tomomi

2010-05-01

The current intense discussion of the green house effect, that has been one of the main focuses on the carbon cycle in environmental systems of the earth, seems to be weakened the importance related to the effect of carbonic materials on substance movement in the aquatic environments; though it has just begun to be referred recently. Because dissolved organic carbon (DOC) in stream flows believes to play a main role of the carbon cycle in the fresh water environment, seasonal changes in DOC discharge were investigated in catchments with various scale and land use, especially in forested catchments which are one of the important sources of DOC. In order to understand the fundamental characteristics of the discharge of dissolved organic materials, stream flows, DOC, and fulvic acid like materials (FA) included in stream flows were measured in a coniferous forested head watershed. The watershed is located at the southeast edge of the Kanto mountain and is 40 km west of Tokyo with the elevation from 720 to 820 m and mean slope gradient of 38 degrees. Geology of the watershed is underlain by the sequence of mud and sand stones in Jurassic and the soil in the watershed is Cambisol (Inceptisols). The watershed composes of a dense cypress and cedar forest of 45 years old with poor understory vegetation. Observations were carried out for 6 rain storms of which the total precipitations ranged between 16.2 and 117.4 mm. The magnitude of the storms was classified into small, middle, and big events on the basis of the total precipitation of around 20, 40, and more than 70 mm. Stream flows were collected during the storm events by 1 hour interval and were passed through the 0.45 μm filters, and then the DOC concentrations in the flows were measured with a total organic carbon analyzer. The relative concentrations of fulvic acid (FA) in the flows were monitored with three dimensional excitations emission matrix fluorescence spectroscopy, because fulvic acid shows distinctive fluorescence peaks at around the excitation wave length of 340 nm and emission wave length of 440 nm. The timing of the peaks in DOC and FA occurred simultaneously or within 30 minutes prior to those in the stream flows. The relationship between DOC and stream flow showed linear correlations with various gradients in each event. However, the relationship between FA and stream flow showed the linear correlations only for the small and middle events and clockwise hysteresis relations occurred in the big storm events. The relationship between DOC and FA showed the linear correlations both for the extracted water of the shallow soil and for stream base flow composed mostly of groundwater discharge. However, the relationship in the storm flow closely distributed at that in the extracted water of the shallow soil. This thing reveals that DOC and FA were mainly flashed out from the shallow soil during the rain storm events. The quick rising and recession of the fulvic acid was likely provided by quick rain water discharge through the surface or near surface of the slope. However, the overland flow were rare in the watershed during the rain storms. This indicates that the rapid shallow subsurface flow, passed mainly through preferential flow pathways at the slope surface within the loose litter and root-permeated zone, was the main cause of the difference in discharge regimes between DOC and FA. The shallow subsurface flow may have flushed the FA in the near-surface of the soil, and then the relatively predominant discharge of DOC must have been caused during the big rain storm event.

View from Space Shows Winter Storm Sweep Over U.S. East Coast

NASA Image and Video Library

2015-03-05

A winter storm was bringing snow, sleet and freezing rain from lower Mississippi Valley to Northeastern U.S. on Thursday, March 5, 2015. A new NASA animation of NOAA's GOES-East satellite imagery showed the progression of the clouds associated with the storm system that triggered winter storm warnings and winter weather advisories from the southern Plains eastward through the Mid-Atlantic and southern New England coast. The system also triggered flood warnings along and to the west of the central Appalachians. An animation of GOES satellite visible and infrared imagery from March 3 through March 5 showed clouds associated with a cold front push over U.S. East coast. Behind the front, Arctic air is expected to drop low temperatures into the single numbers from Washington, D.C. to Minnesota overnight. Temperatures in the Carolinas and Tennessee are expected to drop to the low 20s. NOAA's National Weather Service Weather Prediction Center (NWS NPC) in College Park, Maryland noted "a strong cold front moving across the eastern U.S. will bring heavy snow from parts of the Ohio Valley to the Northeast today (March 5) with rain, freezing rain and sleet possible from parts of the lower Mississippi Valley across the Southeast to the southern Mid-Atlantic. Snowfall totals of 5 to 10 inches are possible for some areas. Winter Storm Warnings remain in effect from Texas to Nantucket." The animation ends at 17:45 UTC (12:45 p.m. EST). Before the end of the animation, the low pressure center along an arctic frontal boundary was nearly stationary over western North Carolina at 9 a.m. EST on March 5, according to the NWS NPC. NWS radar and surface observations indicated an extended swath of precipitation from near the Texas Gulf Coast through the interior eastern U.S. into southern New England. NPC's storm summary noted at that time "rain was changing to sleet/freezing rain and to all snow along a band within this swath as colder air continues to filter in from the north. Some areas in Tennessee, the northern mid-Atlantic and southern New England were reporting moderate to heavy snow." To create the video and imagery, NASA/NOAA's GOES Project takes the cloud data from NOAA's GOES-East satellite and overlays it on a true-color image of land and ocean created by data from the Moderate Resolution Imaging Spectroradiometer, or MODIS, instrument that flies aboard NASA's Aqua and Terra satellites. Together, those data created the entire picture of the storm and show its movement. After the storm system passes, the snow on the ground becomes visible. GOES satellites provide the kind of continuous monitoring necessary for intensive data analysis. Geostationary describes an orbit in which a satellite is always in the same position with respect to the rotating Earth. This allows GOES to hover continuously over one position on Earth's surface, appearing stationary. For updated information about the storm system, visit NOAA's NWS website: www.weather.gov For more information about GOES satellites, visit: www.goes.noaa.gov/ or goes.gsfc.nasa.gov/ Rob Gutro NASA's Goddard Space Flight Center NASA image use policy. NASA Goddard Space Flight Center enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission. Follow us on Twitter Like us on Facebook Find us on Instagram

Linkage of Rainfall-Runoff and Hurricane Storm Surge in Galveston Bay

NASA Astrophysics Data System (ADS)

Deitz, R.; Christian, J.; Wright, G.; Fang, N.; Bedient, P.

2012-12-01

In conjunction with the SSPEED Center, large rainfall events in the upper Gulf of Mexico are being studied in an effort to help design a surge gate to protect the Houston Ship Channel during hurricane events. The ship channel is the world's second largest petrochemical complex and the Coast Guard estimates that a one-month closure would have a $60 billion dollar impact on the national economy. In this effort, statistical design storms, such as the 24-hour PMP, as well as historical storms, like Hurricane Ike, Hurricane Katrina, and Hurricane Rita, are being simulated in a hydrologic/hydraulic model using radar and rain gauge data. VfloTM, a distributed hydrologic model, is being used to quantify the effect that storm size, intensity, and location has on timing and peak flows in the in the upper drainage area. These hydrographs were input to a hydraulic model with various storm surges from Galveston Bay. Results indicate that there is a double peak phenomenon with flows from the west draining days earlier than flows from the north. With storm surge typically lasting 36-48 hours, this indicates the flows from the west are interacting with the storm surge, whereas flows from the north would arrive once the storm surge is receding. Gate operations were optimized in the model to account for the relative timing of upland runoff and hurricane surge, and to quantify the capability of the gate structure to protect the Ship Channel industry.

Electric and kinematic structure of the Oklahoma mesoscale convective system of 7 June 1989

NASA Technical Reports Server (NTRS)

Hunter, Steven M.; Schur, Terry J.; Marshall, Thomas C.; Rust, W. D.

1992-01-01

Balloon soundings of electric field in Oklahoma mesoscale convective systems (MCS) were obtained by the National Severe Storms Laboratory in the spring of 1989. This study focuses on a sounding made in the rearward edge of an MCS stratiform rain area on 7 June 1989. Data from Doppler radars, a lightning ground-strike location system, satellite, and other sources is used to relate the mesoscale attributes of the MCS to the observed electric-field profile.

Radar derived spatial statistics of summer rain. Volume 1: Experiment description

NASA Technical Reports Server (NTRS)

Katz, I.; Arnold, A.; Goldhirsh, J.; Konrad, T. G.; Vann, W. L.; Dobson, E. B.; Rowland, J. R.

1975-01-01

An experiment was performed at Wallops Island, Virginia, to obtain a statistical description of summer rainstorms. Its purpose was to obtain information needed for design of earth and space communications systems in which precipitation in the earth's atmosphere scatters or attenuates the radio signal. Rainstorms were monitored with the high resolution SPANDAR radar and the 3-dimensional structures of the storms were recorded on digital tape. The equipment, the experiment, and tabulated data obtained during the experiment are described.

Precipitation Discrimination from Satellite Infrared Temperatures over the CCOPE Mesonet Region.

NASA Astrophysics Data System (ADS)

Weiss, Mitchell; Smith, Eric A.

1987-06-01

A quantitative investigation of the relationship between satellite-derived cloud-top temperature parameters and the detection of intense convective rainfall is described. The area of study is that of the Cooperative Convective Precipitation Experiment (CCOPE), which was held near Miles City, Montana during the summer of 1981. Cloud-top temperatures, derived from the GOES-West operational satellite, were used to calculate a variety of parameters for objectively quantifying the convective intensity of a storm. A dense network of rainfall provided verification of surface rainfall. The cloud-top temperature field and surface rainfall data were processed into equally sized grid domains in order to best depict the individual samples of instantaneous precipitation.The technique of statistical discriminant analysis was used to determine which combinations of cloud-top temperature parameters best classify rain versus no-rain occurrence using three different rain-rate cutoffs: 1, 4, and 10 mm h1. Time lags within the 30 min rainfall verification were tested to determine the optimum time delay associated with rainfall reaching the ground.A total of six storm cases were used to develop and test the statistical models. Discrimination of rain events was found to be most accurate when using a 10 mm h1 rain-rate cutoff. Use parameters designated as coldest cloud-top temperature, the spatial mean of coldest cloud-top temperature, and change over time of mean coldest cloud-top temperature were found to be the best classifiers of rainfall in this study. Combining both a 10-min time lag (in terms of surface verification) with a 10 mm h1 rain-rate threshold resulted in classifying over 60% of all rain and no-rain cases correctly.

Area and shape metrics of rainfall fields associated with tropical cyclones landfalling over the western Gulf of Mexico and Caribbean Sea

NASA Astrophysics Data System (ADS)

Zhou, Y.

2017-12-01

The rainfall associated with TCs making landfall over western Gulf Coast and Caribbean Sea Coast caused numerous fatalities and divesting damage, however, few studies have been done over these regions. This study examines spatial pattern of rain fields associated with TCs making landfall over western Gulf Coast and Caribbean Sea Coast during 1998-2015 through a Geographic Information System (GIS)-based analysis of satellite-estimated rain rates. Regions of light rainfall (rain rate > 2.5 mm/h) and moderate rainfall (rain rate > 5.0 mm/h) during entire life cycle of each TC are converted into polygons and measurements are made of their area, dispersion and displacement during entire life cycle. The metric of dispersion is calculated for the entire rain field as defined by outlining light and moderate rain rates. The displacement to east and north is calculated by area weighted methods. There are three main objectives of this study. The first goal is to measure the area and spatial distribution of rain fields of TCs making landfall over the western Gulf and Caribbean Sea coastlines. We examine in which regions, the light and moderate rainfall area, dispersion and displacement of rainfall have higher values, and how they change during the entire TC life cycle. The second goal is to determine to determine which environmental conditions are associated with the spatial configuration of light and moderate rain rates. The conditions include storm intensity, motion direction and speed, total precipitable water and wind shear. Last, we determine the time that rainfall reaches land relative to the time that the storm's center makes landfall and durations of rainfall from TCs over land.

Acid Rain

USGS Publications Warehouse

Bricker, Owen P.; Rice, Karen C.

1995-01-01

Although acid rain is fading as a political issue in the United States and funds for research in this area have largely disappeared, the acidity of rain in the Eastern United States has not changed significantly over the last decade, and it continues to be a serious environmental problem. Acid deposition (commonly called acid rain) is a term applied to all forms of atmospheric deposition of acidic substances - rain, snow, fog, acidic dry particulates, aerosols, and acid-forming gases. Water in the atmosphere reacts with certain atmospheric gases to become acidic. For example, water reacts with carbon dioxide in the atmosphere to produce a solution with a pH of about 5.6. Gases that produce acids in the presence of water in the atmosphere include carbon dioxide (which converts to carbonic acid), oxides of sulfur and nitrogen (which convert to sulfuric and nitric acids}, and hydrogen chloride (which converts to hydrochloric acid). These acid-producing gases are released to the atmosphere through natural processes, such as volcanic emissions, lightning, forest fires, and decay of organic matter. Accordingly, precipitation is slightly acidic, with a pH of 5.0 to 5.7 even in undeveloped areas. In industrialized areas, most of the acid-producing gases are released to the atmosphere from burning fossil fuels. Major emitters of acid-producing gases include power plants, industrial operations, and motor vehicles. Acid-producing gases can be transported through the atmosphere for hundreds of miles before being converted to acids and deposited as acid rain. Because acids tend to build up in the atmosphere between storms, the most acidic rain falls at the beginning of a storm, and as the rain continues, the acids "wash out" of the atmosphere.

Climate Change Increases Reproductive Failure in Magellanic Penguins

PubMed Central

Boersma, P. Dee; Rebstock, Ginger A.

2014-01-01

Climate change is causing more frequent and intense storms, and climate models predict this trend will continue, potentially affecting wildlife populations. Since 1960 the number of days with >20 mm of rain increased near Punta Tombo, Argentina. Between 1983 and 2010 we followed 3496 known-age Magellanic penguin (Spheniscus magellanicus) chicks at Punta Tombo to determine how weather impacted their survival. In two years, rain was the most common cause of death killing 50% and 43% of chicks. In 26 years starvation killed the most chicks. Starvation and predation were present in all years. Chicks died in storms in 13 of 28 years and in 16 of 233 storms. Storm mortality was additive; there was no relationship between the number of chicks killed in storms and the numbers that starved (P = 0.75) or that were eaten (P = 0.39). However, when more chicks died in storms, fewer chicks fledged (P = 0.05, R 2 = 0.14). More chicks died when rainfall was higher and air temperature lower. Most chicks died from storms when they were 9–23 days old; the oldest chick killed in a storm was 41 days old. Storms with heavier rainfall killed older chicks as well as more chicks. Chicks up to 70 days old were killed by heat. Burrow nests mitigated storm mortality (N = 1063). The age span of chicks in the colony at any given time increased because the synchrony of egg laying decreased since 1983, lengthening the time when chicks are vulnerable to storms. Climate change that increases the frequency and intensity of storms results in more reproductive failure of Magellanic penguins, a pattern likely to apply to many species breeding in the region. Climate variability has already lowered reproductive success of Magellanic penguins and is likely undermining the resilience of many other species. PMID:24489663

An experimental study of microwave scattering from rain- and wind-roughened seas

NASA Technical Reports Server (NTRS)

Bliven, L. F.; Giovanangeli, J.-P.

1993-01-01

This paper investigates radar cross-section (RCS) characteristics of rain- and wind-roughened sea-surfaces. We conducted experiments in laboratory wind-wave tanks using artificial rain. The study includes light rain rates, light wind speeds, and combinations of these. A 36 Ghz scatterometer was operated at 30 deg incidence angle and with vertical polarization. RCS data were obtained not only with the scatterometer pointing up-wind but also as a function of azimuthal angle. We use a scatterometer rain and wind model SRWM-1, which relates the total average RCS in storms to the sum of the average RCS due to rain plus the average RCS due to wind. Implications of the study for operational monitoring of wind in rainy oceanic areas by satellite-borne instruments is discussed.

Floods of May and June 2004 in Central and Eastern Ohio: FEMA Disaster Declaration 1519

USGS Publications Warehouse

Ebner, Andrew D.; Straub, David E.; Lageman, Jonathan D.

2008-01-01

Several severe thunderstorms that passed through Ohio between May 17 and June 17, 2004, produced large amounts of rain in an already wet central and eastern Ohio, resulting in flooding in this region from May 18 to June 21, 2004. Record peak streamflow occurred at three U.S. Geological Survey (USGS) streamgages. Damages caused by the flooding resulting from these storms were severe enough that 25 counties in central and eastern Ohio were declared Federal disaster areas. In all, there were two storm- or flood-related deaths, 3,529 private structures damaged or destroyed, and an estimated $43 million in damages. This report describes the meteorological factors that resulted in severe flooding in central and eastern Ohio between May 18 and June 21, 2004, and addresses the damages caused by the storms and flooding. Peak-stage, peak-streamflow, and recurrence-interval data are reported for selected USGS streamgages. Flood profiles determined by the USGS are presented for selected streams.

The evolution of convective storms from their footprints on the sea as viewed by synthetic aperture radar from space

NASA Technical Reports Server (NTRS)

Atlas, David; Black, Peter G.

1994-01-01

SEASAT synthetic aperture radar (SAR) echoes from the sea have previously been shown to be the result of rain and winds produced by convective stroms; rain damps the surface waves and causes ech-free holes, while the diverging winds associated with downdraft generate waves and associated echoes surrounding the holes. Gust fronts are also evident. Such a snapshot from 8 July 1978 has been examined in conjunction with ground-based radar. This leads to the conclusion that the SAR storm footprints resulted from storm processes that occurred up to an hour or more prior to the snapshot. A sequence of events is discerned from the SAR imagery in which new cell growth is triggered in between the converging outflows of two preexisting cells. In turn, the new cell generates a mini-squall line along its expanding gust front. While such phenomena are well known over land, the spaceborne SAR now allows important inferences to be made about the nature and frequency of convective storms over the oceans. The storm effects on the sea have significant implications for spaceborne wind scatterometry and rainfall measurements. Some of the findings herein remain speculative because of the great distance to the Miami weather radar-the only source of corroborative data.

Decentralization of storm runoff via engagement of social and cultural capitals - implications for the management of flood risk at the municipal scale

EPA Science Inventory

This research tests a novel method that focuses limited community resources on a decentralized approach to storm water management. A reverse auction was used to relieve legal constraints on management implementation on private land. Residents voluntarily bid on rain gardens and r...

Changes in storm peak flows after clearcut logging

Treesearch

Jack Lewis

1997-01-01

Streamflow in a rain-dominated, 473-ha watershed bearing second-growth redwood forest was monitored at 13 locations before and after 50% of the watershed was logged, primarily by clearcutting. Three gauged subwatersheds were maintained as unlogged controls through-out the 11-year study period. The analysis included 526 observations of peak flow from 59 storm events....

Climate variability, snow, and physiographic controls on storm hydro graphs in small forested basins, western Cascades, Oregon

Treesearch

Reed M. Perkins; Julia A. Jones

2008-01-01

Large floods are often attributed to the melting of snow during a rain event. This study tested how climate variability, snowpack presence, and basin physiography were related to storm hydrograph shape in three small (2) basins with old-growth forest in western Oregon. Relationships between hydrograph characteristics and precipitation...

Storm-related mortality--central Texas, October 17-31, 1998.

PubMed

2000-02-25

On October 17, 1998, a series of storms moved across the central and south regions of Texas, dropping up to 22 inches of rain in some areas and spawning several tornados. Sixty Texas counties (24%) reported flooding during October 17-19. Thirty-six counties became eligible for federal and/or state assistance as a result of damages suffered from this storm system during October 17-31. Estimated flood damage was approximately $900 million, including damage to 12,000 homes, 700 businesses, and public property. This report summarizes findings of an epidemiologic investigation of 31 deaths associated with the storm system.

KSC-08pd2429

NASA Image and Video Library

2008-08-21

CAPE CANAVERAL, Fla. – At NASA's Kennedy Space Center, this alligator was spotted cruising the flood waters caused by Tropical Storm Fay. The storm passed over the center Aug. 20 and then stalled offshore, bringing with it heavy rain and tropical storm force wind. Kennedy closed Aug. 19 because of Fay and reopened for normal operations Aug. 22. Based on initial assessments, there was no damage to space flight hardware, such as the space shuttles and Hubble Space Telescope equipment. Some facilities did sustain minor damage. Photo credit: NASA/Jack Pfaller

Using the JPL Tropical Cyclone Information System to study the climatology of hurricane precipitation structure from 10 years of passive microwave satellite observations in the Atlantic

NASA Astrophysics Data System (ADS)

Hristova-Veleva, Svetla; Haddad, Ziad; Knosp, Brian; Lambrigtsen, Bjorn; Li, P. Peggy; Poulsen, William; Seo, Eun-Kyoung; Shen, Tsae-Pyng; Turk, Francis J.; Vu, Quoc

2013-04-01

In spite of recent improvements in hurricane track forecast accuracy, currently there are still many unanswered questions about the physical processes that determine hurricane genesis, and evolution. Furthermore, a significant amount of work remains to be done in validating and improving hurricane forecast models. None of this can be accomplished without a comprehensive set of multi-parameter observations that are relevant to both the large-scale and the storm-scale processes in the atmosphere and in the ocean. Despite the significant amount of satellite observations today, they are still underutilized in hurricane research and operations, due to complexity and volume. To facilitate hurricane research, we developed the JPL Tropical Cyclone Information System (TCIS) of multi-instrument satellite observations pertaining to: i) the thermodynamic and microphysical structure of the storms; ii) the air-sea interaction processes; iii) the larger-scale environment as depicted by the SST and the Total Precipitable Water of the environment (Hristova-Veleva et al., 2008, 2011). Our goal was to create a one-stop place to provide the researchers with an extensive set of observed hurricane data, and their graphical representation, organized in an easy way to determine when coincident observations from multiple instruments are available. In this study we use the 10+ years of passive microwave observations of Atlantic hurricanes to create composite structures that are segregated by hurricane category and by intensification rate. The use of composite structures provides a statistically robust framework (e.g. Rogers et al., 2012). We analyze the storm asymmetry as depicted by several factors - brightness temperatures and their derivatives such as a newly-develop Rain Indicator and a new convective/stratiform separation that is based on the value and the spatial variability of this Rain Indicator. The goal is to determine whether the storm morphology (in particular, the storm asymmetry or lack thereof) carries predictive skills regarding the potential for intensification. The presentation will describe the JPL TCIS and the results of our analysis of the passive microwave satellite observations of the Atlantic hurricanes. Refernces: Hristova-Veleva, S. M., C. Ao, Y. Chao, V. Dang, R. Fovell, M. Garay, Z. Haddad, B. Knosp, B. Lambrigtsen, P. P. Li, K. J. Park, W. Poulsen, H. Su, S. Tanelli, D. Vane, Q. A. Vu, J. Willis, D. L. Wu, 2008: "Using the JPL Tropical Cyclone Information System for Research and Applications", AMS 28th Hurricane and Tropical Meteorology Conference, Orlando, FL, 28Apr.-02May 2008 Hristova-Veleva, S. M., A. Chau, Z. Haddad, B. Knosp, B. Lambrigtsen, P. P. Li, E. Rodriguez, T. -. P. Shen, B. Stiles, H. Su, J. Turk, and Q. Vu, 2011: "Impact of microphysical parameterizations on the structure and intensity of simulated hurricanes: Using satellite data to determine the parameterizations that produce most realistic storms", 14th Conference on Mesoscale Processes, 1-4 August 2011, Los Angeles, California Rogers, R., S. Lorsolo, P. Reasor, J. Gamache, F. Marks, 2012: Multiscale Analysis of Tropical Cyclone Kinematic Structure from Airborne Doppler Radar Composites. Mon. Wea. Rev., 140, 77-99.

Wind-driven rain and its implications for natural hazard management

NASA Astrophysics Data System (ADS)

Marzen, Miriam; Iserloh, Thomas; de Lima, João L. M. P.; Fister, Wolfgang; Ries, Johannes B.

2017-04-01

Prediction and risk assessment of hydrological extremes are great challenges. Following climate predictions, frequent and violent rainstorms will become a new hazard to several regions in the medium term. Particularly agricultural soils will be severely threatened due to the combined action of heavy rainfall and accompanying winds on bare soil surfaces. Basing on the general underestimation of the effect of wind on rain erosion, conventional soil erosion measurements and modeling approaches lack related information to adequately calculate its impact. The presented experimental-empirical approach shows the powerful impact of wind on the erosive potential of rain. The tested soils had properties that characterise three different environments 1. Silty loam of semi-arid Mediterranean dryfarming and fallow, 2. clayey loam of humid agricultural sites and 3. cohesionless sandy substrates as found at coasts, dune fields and drift-sand areas. Erosion was found to increase by a factor of 1.3 to 7.1, depending on site characteristics. Complementary tests with a laboratory procedure were used to quantify explicitly the effect of wind on raindrop erosion as well as the influence of substrate, surface structure and slope on particle displacement. These tests confirmed the impact of wind-driven rain on total erosion rates to be of great importance when compared to all other tested factors. To successfully adapt soil erosion models to near-future challenges of climate change induced rain storms, wind-driven rain is supposed to be introduced into the hazard management agenda.

Use of multiple correspondence analysis (MCA) to identify interactive meteorological conditions affecting relative throughfall

NASA Astrophysics Data System (ADS)

Van Stan, John T.; Gay, Trent E.; Lewis, Elliott S.

2016-02-01

Forest canopies alter rainfall reaching the surface by redistributing it as throughfall. Throughfall supplies water and nutrients to a variety of ecohydrological components (soil microbial communities, stream water discharge/chemistry, and stormflow pathways) and is controlled by canopy structural interactions with meteorological conditions across temporal scales. This work introduces and applies multiple correspondence analyses (MCAs) to a range of meteorological thresholds (median intensity, median absolute deviation (MAD) of intensity, median wind-driven droplet inclination angle, and MAD of wind speed) for an example throughfall problem: identification of interacting storm conditions corresponding to temporal concentration in relative throughfall beyond the median observation (⩾73% of rain). MCA results from the example show that equalling or exceeding rain intensity thresholds (median and MAD) corresponded with temporal concentration of relative throughfall across all storms. Under these intensity conditions, two wind mechanisms produced significant correspondences: (1) high, steady wind-driven droplet inclination angles increased surface wetting; and (2) sporadic winds shook entrained droplets from surfaces. A discussion is provided showing that these example MCA findings agree well with previous work relying on more historically common methods (e.g., multiple regression and analytical models). Meteorological threshold correspondences to temporal concentration of relative throughfall at our site may be a function of heavy Tillandsia usneoides coverage. Applications of MCA within other forests may provide useful insights to how temporal throughfall dynamics are affected for drainage pathways dependent on different structures (leaves, twigs, branches, etc.).

New Observations of C-band Brightness Temperatures and Ocean Surface Wind Speed and Rain Rate From the Hurricane Imaging Radiometer (HIRAD)

NASA Technical Reports Server (NTRS)

Miller, Timothy L.; James, M. W.; Roberts, J. B.; Buckley, C. D.; Biswas, S.; May, C.; Ruf, C. S.; Uhlhorn, E. W.; Atlas, R.; Black, P.;

Analysis on LID for highly urbanized areas' waterlogging control: demonstrated on the example of Caohejing in Shanghai.

PubMed

Liao, Z L; He, Y; Huang, F; Wang, S; Li, H Z

2013-01-01

Although a commonly applied measure across the United States and Europe for alleviating the negative impacts of urbanization on the hydrological cycle, low impact development (LID) has not been widely used in highly urbanized areas, especially in rapidly urbanizing cities in developing countries like China. In this paper, given five LID practices including Bio-Retention, Infiltration Trench, Porous Pavement, Rain Barrels, and Green Swale, an analysis on LID for highly urbanized areas' waterlogging control is demonstrated using the example of Caohejing in Shanghai, China. Design storm events and storm water management models are employed to simulate the total waterlogging volume reduction, peak flow rate reduction and runoff coefficient reduction of different scenarios. Cost-effectiveness is calculated for the five practices. The aftermath shows that LID practices can have significant effects on storm water management in a highly urbanized area, and the comparative results reveal that Rain Barrels and Infiltration Trench are the two most suitable cost-effective measures for the study area.

Coronal Rain, Solar Storm

NASA Image and Video Library

2010-03-19

Explanation: In this picture, the Sun's surface is quite dark. A frame from a movie recorded on November 9th by the orbiting TRACE telescope, it shows coronal loops lofted over a solar active region. Glowing brightly in extreme ultraviolet light, the hot plasma entrained above the Sun along arching magnetic fields is cooling and raining back down on the solar surface. Hours earlier, on November 8th, astronomers had watched this particular active region produce a not so spectacular solar flare. Still, the M-class flare spewed forth an intense storm of particles, suddenly showering satellites near the Earth with high energy protons. The flare event was also associated with a large coronal mass ejection, a massive cloud of material which impacted our fair planet's magnetic field about 31 hours later. The result ... a strong geomagnetic storm. Credit: NASA/GSFC/TRACE To learn more go to: nasascience.nasa.gov/missions/trace To learn more about NASA's Sun Earth Day go here: sunearthday.nasa.gov/2010/index.php

Test of the efficiency of three storm water quality models with a rich set of data.

PubMed

Ahyerre, M; Henry, F O; Gogien, F; Chabanel, M; Zug, M; Renaudet, D

2005-01-01

The objective of this article is to test the efficiency of three different Storm Water Quality Model (SWQM) on the same data set (34 rain events, SS measurements) sampled on a 42 ha watershed in the center of Paris. The models have been calibrated at the scale of the rain event. Considering the mass of pollution calculated per event, the results on the models are satisfactory but that they are in the same order of magnitude as the simple hydraulic approach associated to a constant concentration. In a second time, the mass of pollutant at the outlet of the catchment at the global scale of the 34 events has been calculated. This approach shows that the simple hydraulic calculations gives better results than SWQM. Finally, the pollutographs are analysed, showing that storm water quality models are interesting tools to represent the shape of the pollutographs, and the dynamics of the phenomenon which can be useful in some projects for managers.

Export of nutrients and major ionic solutes from a rain forest catchment in the Central Amazon Basin

NASA Astrophysics Data System (ADS)

Lesack, Lance F. W.

1993-03-01

The relative roles of base flow runoff versus storm flow runoff versus subsurface outflow in controlling total export of solutes from a 23.4-ha catchment of undisturbed rain forest in the central Amazon Basin were evaluated from water and solute flux measurements performed over a 1 year period. Solutes exported via 173 storms during the study were estimated from stream water samples collected during base flow conditions and during eight storms, and by utilizing a hydrograph separation technique in combination with a mixing model to partition storm flow from base flow fluxes. Solutes exported by subsurface outflow were estimated from groundwater samples from three nests of piezometers installed into the streambed, and concurrent measurements of hydraulic conductivity and hydraulic head gradients. Base flow discharge represented 92% of water outflow from the basin and was the dominant pathway of solute export. Although storm flow discharge represented only 5% of total water outflow, storm flow solute fluxes represented up to 25% of the total annual export flux, though for many solutes the portion was less. Subsurface outflow represented only 2.5% of total water outflow, and subsurface solute fluxes never represented more than 5% of the total annual export flux. Measurement errors were relatively high for storm flow and subsurface outflow fluxes, but cumulative measurement errors associated with the total solute fluxes exported from the catchment, in most cases, ranged from only ±7% to 14% because base flow fluxes were measured relatively well. The export fluxes of most solutes are substantially less than previously reported for comparable small catchments in the Amazon basin, and these differences cannot be reconciled by the fact that storm flow and subsurface outflows were not appropriately measured in previous studies.

Simulating double-peak hydrographs from single storms over mixed-use watersheds

Treesearch

Yang Yang; Theodore A. Endreny; David J. Nowak

2015-01-01

Two-peak hydrographs after a single rain event are observed in watersheds and storms with distinct volumes contributing as fast and slow runoff. The authors developed a hydrograph model able to quantify these separate runoff volumes to help in estimation of runoff processes and residence times used by watershed managers. The model uses parallel application of two...

Aspen clearcutting increases snowmelt and storm flow peaks in north central Minnesota

Treesearch

Elon S. Verry; Jeffrey R. Lewis; Kenneth N. Brooks

1983-01-01

Clearcutting aspen from the upland portion of an upland peatland watershed in north central Minnesota caused snowmelt peak discharge to increase 11 to 143 percent. Rainfall peak discharge size increased as much as 250 percent during the first two years after clearcutting, then decreased toward precutting levels in subsequent years. Storm flow volumes from rain during...

Seasonal Variations in Survival of Indicator Bacteria in Soil and Their Contribution to Storm-water Pollution

PubMed Central

Van Donsel, Dale J.; Geldreich, Edwin E.; Clarke, Norman A.

1967-01-01

Survival of a fecal coliform (Escherichia coli) and a fecal streptococcus (Streptococcus faecalis var. liquifaciens) was studied through several years at shaded and exposed outdoor soil plots. Death rates for both organisms were calculated for the different seasons at both sites. The 90% reduction times for the fecal coliform ranged from 3.3 days in summer to 13.4 days in autumn. For the fecal streptococcus, 90% reduction times were from 2.7 days in summer to 20.1 days in winter. During summer, the fecal coliform survived slightly longer than the fecal streptococcus; during autumn, survival was the same; and in spring and winter the fecal streptococcus survived much longer than the fecal coliform. Both organisms were isolated from storm-water runoff collected below a sampling site when counts were sufficiently high in soil. Isolation was more frequent during prolonged rains, lasting up to 10 days, than during short rain storms. There was evidence of aftergrowth of nonfecal coliforms in the soil as a result of temperature and rainfall variations. Such aftergrowth may contribute to variations in bacterial count of storm-water runoff which have no relation to the sanitary history of the drainage area. PMID:16349746

Use of NEXRAD radar-based observations for quality control of in-situ rain gauge measurements

NASA Astrophysics Data System (ADS)

Nelson, B. R.; Prat, O.; Leeper, R.

2017-12-01

Rain gauge quality control is an often over looked important step in the archive of historical precipitation estimates. We investigate the possibilities that exist for using ground based radar networks for quality control of rain gauge measurements. This process includes the point to pixel comparisons of the rain gauge measurements with NEXRAD observations. There are two NEXRAD based data sets used for reference; the NCEP stage IV and the NWS MRMS gridded data sets. The NCEP stage IV data set is available at 4km hourly for the period 2002-present and includes the radar-gauge bias adjusted precipitation estimate. The NWS MRMS data set includes several different variables such as reflectivity, radar-only estimates, precipitation flag, and radar-gauge bias adjusted precipitation estimates. The latter product provides for much more information to apply quality control such as identification of precipitation type, identification of storm type and Z-R relation. In addition, some of the variables are available at 5-minute scale. The rain gauge networks that are investigated are the Climate Reference Network (CRN), the Fischer-Porter Hourly Precipitation Database (HPD), and the Hydrometeorological Automated Data System (HADS). The CRN network is available at the 5-minute scale, the HPD network is available at the 15-minute and hourly scale, and HADS is available at the hourly scale. The varying scales present challenges for comparisons. However given the higher resolution radar-based products we identify an optimal combination of rain gauge observations that can be compared to the radar-based information. The quality control process focuses on identifying faulty gauges in direct comparison while a deeper investigation focuses on event-based differences from light rain to extreme storms.

Precipitation nutrients in the open and under two forests in Minnesota

Treesearch

Elon S. Verry; D.R. Timmons

1977-01-01

Concentrations of N, P, K, Ca, Mg, and Na were measured in rain and snow in the open, and in throughfall and stemflow under black spruce and aspen forests in north-central Minnesota. Concentrations of total P in rain and black spruce throughfall were inversely related to storm size. Annual precipitation nutrient inputs to the forest floor were calculated for each site...

Using wireless sensor networks to improve understanding of rain-on-snow events across the Sierra Nevada

NASA Astrophysics Data System (ADS)

Maurer, T.; Avanzi, F.; Oroza, C.; Malek, S. A.; Glaser, S. D.; Bales, R. C.; Conklin, M. H.

2017-12-01

We use data gathered from Wireless Sensor Networks (WSNs) between 2008 and 2017 to investigate the temporal/spatial patterns of rain-on-snow events in three river basins of California's Sierra Nevada. Rain-on-snow transitions occur across a broad elevation range (several hundred meters), both between storms and within a given storm, creating an opportunity to use spatially and temporally dense data to forecast and study them. WSNs collect snow depth; meteorological data; and soil moisture and temperature data across relatively dense sensor clusters. Ten to twelve measurement nodes per cluster are placed across 1-km2 areas in locations representative of snow patterns at larger scales. Combining precipitation and snow data from snow-pillow and climate stations with an estimation of dew-point temperature from WSNs, we determine the frequency, timing, and geographic extent of rain-on-snow events. We compare these results to WSN data to evaluate the impact of rain-on-snow events on snowpack energy balance, density, and depth as well as on soil moisture. Rain-on-snow events are compared to dry warm-weather days to identify the relative importance of rain and radiation as the primary energy input to the snowpack for snowmelt generation. An intercomparison of rain-on-snow events for the WSNs in the Feather, American, and Kings River basins captures the behavior across a 2° latitudinal range of the Sierra Nevada. Rain-on-snow events are potentially a more important streamflow generation mechanism in the lower-elevation Feather River basin. Snowmelt response to rain-on-snow events changes throughout the wet season, with later events resulting in more melt due to snow isothermal conditions, coarser grain size, and more-homogeneous snow stratigraphy. Regardless of snowmelt response, rain-on-snow events tend to result in decreasing snow depth and a corresponding increase in snow density. Our results demonstrate that strategically placed WSNs can provide the necessary data at high temporal resolution to investigate how hydrologic responses evolve in both space and time, data not available from operational networks.

Modeling of storm runoff and pollutant wash off processes during storm event in rapidly urbanizing catchment

NASA Astrophysics Data System (ADS)

Qin, H. P.; Yu, X. Y.; Khu, S. T.

2009-04-01

Many urban catchments in developing countries are undergoing fast economic growth, population expansion and land use/cover change. Due to the mixture of agricultural/industrial/residential land use or different urbanization level as well as lack of historical monitoring data in the developing area, storm-water runoff pollution modeling is faced with challenges of considerable spatial variations and data insufficiency. Shiyan Reservoir catchment is located in the rapidly urbanizing coastal region of Southeast China. It has six sub-catchments with largely different land use patterns and urbanization levels. A simple semi-distributed model was used to simulate the storm-water runoff pollution process during storm event in the catchment. The model adopted modified IHACRES model and exponential wash-off functions to describe storm-runoff and pollutant wash-off processes, respectively, in each of six sub-catchments. Temporary hydrological and water quality monitoring sites were set at the downstream section of each sub-catchment in Feb-May 2007, spanning non-rain and rain seasons. And the model was calibrated for storm-runoff and water quality data during two typical storm events with rainfall amount of 10mm/4hr and 73mm/5hr, respectively. The results indicated that the Nash-Sutcliffe (NS) coefficients are greater than 0.65 and 0.55 respectively for storm-runoff model calibration and validation. However although NS coefficients can reach 0.7~0.9 for pollutant wash-off model calibration based on measured data in each storm event, the simulation data can not fit well with the measured data in model validation. According to field survey observation, many litters and residuals were found to distribute in disorder in some sub-catchments or their drainage systems and to instantaneously wash off into the surface water when the rainfall amount and intensity are large enough. In order to improve storm-water runoff pollution simulation in the catchment, the variations of pollutant source and wash off processes in different storm intensity should be consider in future monitoring and model development. Keywords: storm runoff; wash off; urbanization; catchment modeling; litter; residual

Climatological and meteorological conditions associated with rain-induced periglacial debris flows in the Cascade Range, USA

NASA Astrophysics Data System (ADS)

Parker, L.; Nolin, A. W.

2009-04-01

Title: Climatological and meteorological conditions associated with rain-induced periglacial debris flows in the Cascade Range, USA Authors: L. Parker, A.W. Nolin Affiliation: Department of Geosciences, Oregon State University, Corvallis, Oregon, USA In November of 2006 an intense rainstorm of tropical origin, known colloquially as "Pineapple Express," inundated the Pacific Northwest region of the United States, initiating numerous periglacial debris flows on several of the stratovolcanoes in the Cascade Range of Oregon and Washington. Rain-induced periglacial debris flows are the result of the over-saturation and subsequent collapse of steep moraine in formerly glaciated valleys. These debris flows rapidly aggrade channels, deposit thick sediments in their path, and severely damage infrastructure. Here we focus on Mount Hood, Oregon and Mount Rainier, Washington in the investigation of meteorological and climatological conditions surrounding rain-induced periglacial debris flow events and their variability over time. Both anecdotal and observational evidence suggest that the Pineapple Express storms are a likely triggering mechanism for these rain-induced debris flows on the stratovolcanoes. Dates for the debris flow events for each mountain were linked with corresponding Pineapple Express storm events. Preliminary analysis suggests that one or more particular climatological or meteorological conditions may be central to the initiation of debris flows, though these conditions may not always be present during Pineapple Express storms. Antecedent snowpack conditions are also hypothesized to play an important role in periglacial rain-induced debris flow initiation as the presence of snow cover on the moraines and glaciers is thought to reduce the likelihood of a debris flow. Radiosonde and precipitation data from Salem, Oregon (KSLE) and Quillayute, Washington (KUIL) data are used to determine if freezing levels and precipitation amounts have changed over time for all documented Pineapple Express events. Particular focus is placed on those events associated with debris flows. Additionally, Snowpack Telemetry (SNOTEL) data are used to examine the antecedent snowpack conditions for each debris flow event. These results will ultimately be coupled with research concerning the geomorphological mechanisms behind debris flows on stratovolcanoes in the Cascades, and may lead to improved understanding and future projections concerning the timing, frequency and intensity of rain-induced periglacial debris flow events.

Tropical Storm Allison rapid needs assessment--Houston, Texas, June 2001.

PubMed

2002-05-03

On June 5, 2001, Tropical Storm Allison made landfall on Galveston Island, Texas. During the next 2 days, the system soaked much of southeast Texas and south-central Louisiana with more than 10 inches of rain as it moved slowly northward. On June 7, the storm made a clockwise loop back to the southwest, bringing even more rain to already drenched areas. The record rainfall caused billions of dollars in flood-related damage and approximately 25 deaths and led to a presidential disaster, declaration covering 31 Texas counties (Figure 1) and 28 Louisiana parishes. Harris County, Texas (2000 population: 3,400,578), center of the Houston metropolitan area, was among the hardest hit with some areas receiving up to 37 inches of rain in 24 hours (Figure 2). To evaluate the community's immediate public health needs, the City of Houston Department of Health and Human Services (HDHHS) conducted a rapid needs assessment in the areas most affected by flooding. This report summarizes assessment results, which identified increased illness in persons living in flooded homes, suggesting a need for rapid resolution of flood-related damage and the possibility that residents should seek temporary housing during clean-up and repair. The findings underscore the usefulness of rapid needs assessment as a tool to minimize misinformation, identify actual health threats, and ensure delivery of resources to those with the greatest and most immediate need.

Flash Location, Size, and Rates Relative to the Evolving Kinematics and Microphysics of the 29 May 2012 DC3 Supercell Storm

NASA Astrophysics Data System (ADS)

MacGorman, D. R.; DiGangi, E.; Ziegler, C.; Biggerstaff, M. I.; Betten, D.; Bruning, E. C.

2014-12-01

A supercell thunderstorm was observed on 29 May 2012 during the Deep Convective Clouds and Chemistry (DC3) experiment. This storm was part of a cluster of severe storms and produced 5" hail, an EF-1 tornado, and copious lightning over the course of a few hours. During a period in which flash rates were increasing rapidly, observations were obtained from mobile polarimetric radars and a balloon-borne electric field meter (EFM) and particle imager, while aircraft sampled the chemistry of the inflow and anvil. In addition, the storm was within the domain of the 3-dimensional Oklahoma Lightning Mapping Array (LMA) and the S-band KTLX WSR-88D radar. The focus of this paper is the evolution of flash rates, the location of flash initiations, and the distribution of flash size and flash extent density as they relate to the evolving kinematics and microphysics of the storm for the approximately 30-minute period in which triple-Doppler coverage was available. Besides analyzing reflectivity structure and three-dimensional winds for the entire period, we examine mixing ratios of cloud water, cloud ice, rain, and graupel/hail that have been retrieved by a Lagrangian analysis for three select times, one each at the beginning, middle, and end of the period. Flashes in an around the updraft of this storm were typically small. Flash size tended to increase, and flash rates tended to decrease as distance from the updraft increased. Although flash initiations were most frequent near the updraft, some flashes were initiated near the edge of 30 dBZ cores and propagated into the anvil. Later, some flashes were initiated in the anvil itself, in vertical cells that formed and became electrified tens of kilometers downshear of the main body of the storm. Considerable lightning structure was inferred to be in regions dominated by cloud ice in the upper part of the storm. The continual small discharges in the overshooting top of the storm tended to be near or within 15 dBZ contours, although occasional discharges appeared to extend above the storm.

Northern Minnesota Independence Day storm: a research needs assessment.

Treesearch

W.J. Mattson; D.S. Shriner

2001-01-01

Nearly 500,000 acres of forest and water were severely impacted by a powerful wind and rain storm in northeastern Minnesota on the fourth of July 1999. Trees were uprooted and snapped off in a swath that was 4-12 miles wide and 30 miles long. This document addresses the many ecological and social research needs in nine discipline areas that were generated as a...

Snowpack-runoff relationships for mid-elevation snowpacks on the Workman Creek watersheds of Central Arizona

Treesearch

Gerald J. Gottfried; Daniel G. Neary; Peter F. Ffolliott

2002-01-01

Snowpacks in the southwestern United States melt intermittently throughout the winter. At some mid-elevation locations, between 7,000 and 7,500 ft, snowpacks appear and disappear, depending on the distribution of storms during relatively dry winters. Some winter precipitation can occur as rain during warm storms and is not reflected in the snow course data. The USDA...

KSC-08pd2422

NASA Image and Video Library

2008-08-21

CAPE CANAVERAL, Fla. – Debris covers a road eroded by Tropical Storm Fay near Launch Pad 39A at NASA's Kennedy Space Center. The storm passed over the center Aug. 20 and then stalled offshore, bringing with it heavy rain and tropical storm force wind. Kennedy closed Aug. 19 because of Fay and reopened for normal operations Aug. 22. Based on initial assessments, there was no damage to space flight hardware, such as the space shuttles and Hubble Space Telescope equipment. Some facilities did sustain minor damage. Photo credit: NASA/Jack Pfaller

KSC-08pd2430

NASA Image and Video Library

2008-08-21

CAPE CANAVERAL, Fla. – Due to Tropical Storm Fay, the ground is flooded on a road alongside the turn basin at NASA's Kennedy Space Center. The storm passed over the center Aug. 20 and then stalled offshore, bringing with it heavy rain and tropical storm force wind. Kennedy closed Aug. 19 because of Fay and reopened for normal operations Aug. 22. Based on initial assessments, there was no damage to space flight hardware, such as the space shuttles and Hubble Space Telescope equipment. Some facilities did sustain minor damage. Photo credit: NASA/Jack Pfaller

KSC-08pd2423

NASA Image and Video Library

2008-08-21

CAPE CANAVERAL, Fla. – Flooding and some tree damage near the Vehicle Assembly Building are results from Tropical Storm Fay at NASA's Kennedy Space Center. The storm passed over the center Aug. 20 and then stalled offshore, bringing with it heavy rain and tropical storm force wind. Kennedy closed Aug. 19 because of Fay and reopened for normal operations Aug. 22. Based on initial assessments, there was no damage to space flight hardware, such as the space shuttles and Hubble Space Telescope equipment. Some facilities did sustain minor damage. Photo credit: NASA/Jack Pfaller

KSC-08pd2431

NASA Image and Video Library

2008-08-21

CAPE CANAVERAL, Fla. – Due to Tropical Storm Fay, the roadside canals and surrounding grounds are flooded at NASA's Kennedy Space Center. In the background is the Vehicle Assembly Building. The storm passed over the center Aug. 20 and then stalled offshore, bringing with it heavy rain and tropical storm force wind. Kennedy closed Aug. 19 because of Fay and reopened for normal operations Aug. 22. Based on initial assessments, there was no damage to space flight hardware, such as the space shuttles and Hubble Space Telescope equipment. Some facilities did sustain minor damage. Photo credit: NASA/Ben Smegelsky

KSC-08pd2428

NASA Image and Video Library

2008-08-21

CAPE CANAVERAL, Fla. – An alligator seeks higher ground alongside a road at NASA's Kennedy Space Center during the onslaught of Tropical Storm Fay. The storm passed over the center Aug. 20 and then stalled offshore, bringing with it heavy rain and tropical storm force wind. Kennedy closed Aug. 19 because of Fay and reopened for normal operations Aug. 22. Based on initial assessments, there was no damage to space flight hardware, such as the space shuttles and Hubble Space Telescope equipment. Some facilities did sustain minor damage. Photo credit: NASA/Jack Pfaller

Hydraulic characteristics of low-impact development practices in northeastern Ohio, 2008–2010

USGS Publications Warehouse

Darner, Robert A.; Dumouchelle, Denise H.

2011-01-01

Low-impact development (LID) is an approach to managing stormwater as near to its source as possible; this is accomplished by minimizing impervious surfaces and promoting more natural infiltration and evapotranspiration than is typically associated with developed areas. Two newly constructed LID sites in northeastern Ohio were studied to document their hydraulic characteristics. A roadside best-management practice (BMP) was constructed by replacing about 1,400 linear feet of existing ditches with a bioswale/rain garden BMP consisting of a grassed swale interspersed with rain-garden/overflow structures. The site was monitored in 2008, 2009, and 2010. Although some overflows occurred, numerous precipitation events exceeding the 0.75-inch design storm did not result in overflows. A second study site consists of an 8,200-square-foot parking lot made of a pervious pavers and a rain garden that receives runoff from the roof of a nearby commercial building. A comparison of data from 2009 and 2010 indicates that the median runoff volume in 2010 decreased relative to 2009. The centroid lag times (time difference between centroid of precipitation and centroid of flow) decreased in 2010, most likely due to more intense, shorter duration precipitation events and maturation of the rain garden. Additional data could help quantify the relation between meteorological variables and BMP efficiency.

Modelling erosion on a daily basis, an adaptation of the MMF approach

NASA Astrophysics Data System (ADS)

Shrestha, Dhruba Pikha; Jetten, Victor G.

2018-02-01

Effect of soil erosion causing negative impact on ecosystem services and food security is well known. On the other hand there can be yearly variation of total precipitation received in an area, with the presence of extreme rains. To assess annual erosion rates various empirical models have been extensively used in all the climatic regions. While these models are simple to operate and do not require lot of input data, the effect of extreme rain is not taken into account. Although physically based models are available to simulate erosion processes including particle detachment, transportation and deposition of sediments during a storm they are not applicable for assessing annual soil loss rates. Moreover storm event data may not be available everywhere prohibiting their extensive use.

Interception of rainfall in a young loblolly pine plantation

Treesearch

Marvin D. Hoover

1953-01-01

Those who have sought refuge during a storm have found a tree to be an effective umbrella for a light shower but leaky in a heavy rain. Even so, it is usually possible to stay slightly more dry under forest canopy than in the open. That is because a portion of the rain is stored on leaves and branches and eventually evaporated back to the air. The term interception is...

Mesoscale Magnetosphere-Ionosphere Coupling along Open Magnetic Field Lines Associated with Airglow Patches: Field-aligned Currents and Precipitation

NASA Astrophysics Data System (ADS)

Zou, Y.; Nishimura, Y.; Lyons, L. R.; Shiokawa, K.; Burchill, J. K.; Knudsen, D. J.; Buchert, S. C.; Chen, S.; Nicolls, M. J.; Ruohoniemi, J. M.; McWilliams, K. A.; Nishitani, N.

2016-12-01

Although airglow patches are traditionally regarded as high-density plasma unrelated to local field-aligned currents (FACs) and precipitation, past observations were limited to storm-time conditions. Recent non-storm time observations show patches to be associated with azimuthally narrow ionospheric fast flow channels that substantially contribute to plasma transportation across the polar cap and connect dayside and nightside explosive disturbances. We examine whether non-storm time patches are related also to localized polar cap FACs and precipitation using Swarm- and FAST-imager-radar conjunctions. In Swarm data, we commonly (66%) identify substantial magnetic perturbations indicating FAC enhancements around patches. These FACs have substantial densities (0.1-0.2 μA/m-2) and can be approximated as infinite current sheets (typically 75 km wide) orientated roughly parallel to patches. They usually exhibit a Region-1 sense, i.e. a downward FAC lying eastward of an upward FAC, and can close through Pedersen currents in the ionosphere, implying that the locally enhanced dawn-dusk electric field across the patch is imposed by processes in the magnetosphere. In FAST data, we identify localized precipitation that is enhanced within patches in comparison to weak polar rain outside patches. The precipitation consists of structured or diffuse soft electron fluxes. While the latter resembles polar rain only with higher fluxes, the former consists of discrete fluxes enhanced by 1-2 orders of magnitude from several to several hundred eV. Although the precipitation is not a major contributor to patch ionization, it implies that newly reconnected flux tubes that retain electrons of magnetosheath origin can rapidly traverse the polar cap from the dayside. Therefore non-storm time patches should be regarded as part of a localized magnetosphere-ionosphere coupling system along open magnetic field lines, and their transpolar evolution as a reflection of reconnected flux tubes traveling from the dayside to nightside magnetosphere.

Effects of acid rain and sulfur dioxide on marble dissolution

USGS Publications Warehouse

Schuster, Paul F.; Reddy, Michael M.; Sherwood, Susan I.

1994-01-01

Acid precipitation and the dry deposition of sulfur dioxide (SO2) accelerate damage to carbonate-stone monuments and building materials. This study identified and quantified environmental damage to a sample of Vermont marble during storms and their preceding dry periods. Results from field experiments indicated the deposition of SO2 gas to the stone surface during dry periods and a twofold increase in marble dissolution during coincident episodes of low rain rate and decreased rainfall pH. The study is widely applicable to the analysis of carbonate-stone damage at locations affected by acid rain and air pollution.

Spatial characteristics of observed precipitation fields: A catalog of summer storms in Arizona, Volume 2

NASA Technical Reports Server (NTRS)

Fennessey, N. M.; Eagleson, P. S.; Qinliang, W.; Rodriguez-Iturbe, I.

1986-01-01

The parameters of the conceptual model are evaluated from the analysis of eight years of summer rainstorm data from the dense raingage network in the Walnut Gulch catchment near Tucson, Arizona. The occurrence of measurable rain at any one of the 93 gages during a noon to noon day defined a storm. The total rainfall at each of the gages during a storm day constituted the data set for a single storm. The data are interpolated onto a fine grid and analyzed to obtain: an isohyetal plot at 2 mm intervals, the first three moments of point storm depth, the spatial correlation function, the spatial variance function, and the spatial distribution of the total storm depth. The description of the data analysis and the computer programs necessary to read the associated data tapes are presented.

The extent of wind-induced undercatch in the UK winter storms of 2015

NASA Astrophysics Data System (ADS)

Pollock, Michael; Colli, Matteo; Stagnaro, Mattia; Quinn, Paul; Dutton, Mark; O'Donnell, Greg; Wilkinson, Mark; Black, Andrew; O'Connell, Enda; Lanza, Luca

2016-04-01

The most widely used device for measuring rainfall is the rain gauge, of which the tipping bucket (TBR) is the most prevalent type. Rain gauges are considered by many to be the most accurate method currently available. The data they produce are used in flood-forecasting and flood risk management, water resource management, hydrological modelling and evaluating impacts on climate change; to name but a few. Rain gauges may provide the most accurate measurement of rainfall at a point in space and time, but they are subject to errors - and some gauges are more prone than others. The most significant error is the 'wind-induced undercatch'. This is caused by the gauge itself contributing to an acceleration of the wind speed near the orifice, which disturbs and distorts the airflow. The trajectories of precipitation particles are affected, resulting in an undercatch. Results from Computational Fluid Dynamics (CFD) simulations, presented herein, describe in detail the physical processes contributing to this. High resolution field measurements of rainfall and wind are collected at four field research stations in the UK. Each site is equipped with juxtaposed rain gauges with different funnel profiles, in addition to a WMO reference pit rain gauge measurement. These data describe the rainfall measurement uncertainty. The sites were selected to represent the prevalent rainfall regimes observed in the UK. Two research stations are on the west coast; which is prone to frontal weather systems and storms swept in from the Atlantic, often enhanced by orography. Two are located in the east. Rural lowland and upland areas are represented, both in the west and the east. Urban sites will also have significant undercatch problems but are outside the scope of this study. Data from the four research stations are analysed for the 2015 winter storms which caused devastating flooding in the west of the UK, particularly Cumbria and the Scottish Borders, where two of the sites are located. An assessment of the effect of wind on the rainfall catch during these large storm events is presented for each research station. Based on a reference pit rain gauge, the undercatch for these events is calculated. The difference in rainfall catch between several types of rain gauge mounted at variable heights is also investigated. This work aims to demonstrate the importance of improving the accuracy of rainfall measurements, and to emphasise the need to provide an assessment of the measurement uncertainty. A knowledge gap exists in the understanding of precisely how physical phenomena are contributing to wind-induced undercatch. For instance, a priori, the effect of the wind on the rainfall catch will change depending upon the dimensions of the rain droplets. Rainfall 'type' and rainfall intensity may be able to inform corrections, but rigorous multi-variate statistical analysis of high resolution measurements will be key to the success of these procedures. As the spatio-temporal distribution of rainfall can be highly variable, and each measurement location is different; it is a challenging undertaking to understand and pin down the fundamental processes responsible for the wind-induced undercatch.

Linking ice accretion and crown structure: towards a model of the effect of freezing rain on tree canopies

PubMed Central

Nock, Charles A.; Lecigne, Bastien; Taugourdeau, Olivier; Greene, David F.; Dauzat, Jean; Delagrange, Sylvain; Messier, Christian

2016-01-01

Background and Aims Despite a longstanding interest in variation in tree species vulnerability to ice storm damage, quantitative analyses of the influence of crown structure on within-crown variation in ice accretion are rare. In particular, the effect of prior interception by higher branches on lower branch accumulation remains unstudied. The aim of this study was to test the hypothesis that intra-crown ice accretion can be predicted by a measure of the degree of sheltering by neighbouring branches. Methods Freezing rain was artificially applied to Acer platanoides L., and in situ branch-ice thickness was measured directly and from LiDAR point clouds. Two models of freezing rain interception were developed: ‘IceCube’, which uses point clouds to relate ice accretion to a voxel-based index (sheltering factor; SF) of the sheltering effect of branch elements above a measurement point; and ‘IceTree’, a simulation model for in silico evaluation of the interception pattern of freezing rain in virtual tree crowns. Key Results Intra-crown radial ice accretion varied strongly, declining from the tips to the bases of branches and from the top to the base of the crown. SF for branches varied strongly within the crown, and differences among branches were consistent for a range of model parameters. Intra-crown variation in ice accretion on branches was related to SF (R2 = 0·46), with in silico results from IceTree supporting empirical relationships from IceCube. Conclusions Empirical results and simulations confirmed a key role for crown architecture in determining intra-crown patterns of ice accretion. As suspected, the concentration of freezing rain droplets is attenuated by passage through the upper crown, and thus higher branches accumulate more ice than lower branches. This is the first step in developing a model that can provide a quantitative basis for investigating intra-crown and inter-specific variation in freezing rain damage. PMID:27107412

High-water marks from tropical storm Irene for selected river reaches in northwestern Massachusetts, August 2011

USGS Publications Warehouse

Bent, Gardner C.; Medalie, Laura; Nielsen, Martha G.

2013-01-01

A Presidential Disaster Declaration was issued for Massachusetts, with a focus on the northwestern counties, following flooding from tropical storm Irene on August 28–29, 2011. Three to 10 inches of rain fell during the storm on soils that were susceptible to flash flooding because of wet antecedent conditions. The gage height at one U.S. Geological Survey (USGS) streamgage rose nearly 20 feet in less than 4 hours because of the combination of saturated soils and intense rainfall. Eight of 16 USGS long-term streamgages in western Massachusetts set new peaks of record on August 28 or 29, 2011. To document the historic water levels of the streamflows from tropical storm Irene, the USGS identified, flagged, and surveyed 323 high-water marks in the Deerfield and Hudson- Hoosic River basins in northwestern Massachusetts. Areas targeted for high-water marks were generally upstream and downstream from structures along selected river reaches. Elevations from high-water marks can be used to confirm peak river stages or help compute peak streamflows, to calibrate hydraulic models, or to update flood-inundation and recovery maps. For areas in western Massachusetts that flooded as a result of tropical storm Irene, high-water marks surveyed for this study have helped to confirm or determine instantaneous peak river gage heights at several USGS streamgages.

Typhoon Man-Yi

NASA Technical Reports Server (NTRS)

2007-01-01

Typhoon Man-Yi was pummeling the Japanese island of Okinawa with winds between 230 and 295 kilometers per hour (125-160 knots, 144-184 miles per hour) and heavy rain on the morning of July 13, 2007, when the Moderate Resolution Imaging Spectroradiometer (MODIS) on NASA's Terra satellite captured this image. The immense storm covered hundreds of kilometers with spiraling bands of thunderstorms, though it had lost the distinctive cloud-free eye it exhibited the day before. Typhoons are common in Japan, but powerful typhoons usually strike the island nation later in the year. The Japan Meteorological Agency said that Man-Yi is the fourth typhoon of the 2007 season and may be the most powerful ever observed in the northwest Pacific in July, reported Kyodo News. The Joint Typhoon Warning Center expected the typhoon to strike Kyushu, a southern Japanese island, on July 14, and then curve northeast along the eastern shore of Japan. By the time the storm reaches Tokyo on July 15, it should be degraded to a tropical storm. As of July 13, Typhoon Man-Yi had injured eight and flooded twenty houses in Okinawa, and forced airlines to cancel hundreds of flights, said Kyodo News. The storm was expected to bring heavy rain to Japan's Pacific coast. NASA image created by Jesse Allen, using data provided courtesy of the MODIS Rapid Response team.

Airborne radar and radiometer experiment for quantitative remote measurements of rain

NASA Technical Reports Server (NTRS)

Kozu, Toshiaki; Meneghini, Robert; Boncyk, Wayne; Wilheit, Thomas T.; Nakamura, Kenji

1989-01-01

An aircraft experiment has been conducted with a dual-frequency (10 GHz and 35 GHz) radar/radiometer system and an 18-GHz radiometer to test various rain-rate retrieval algorithms from space. In the experiment, which took place in the fall of 1988 at the NASA Wallops Flight Facility, VA, both stratiform and convective storms were observed. A ground-based radar and rain gauges were also used to obtain truth data. An external radar calibration is made with rain gauge data, thereby enabling quantitative reflectivity measurements. Comparisons between path attenuations derived from the surface return and from the radar reflectivity profile are made to test the feasibility of a technique to estimate the raindrop size distribution from simultaneous radar and path-attenuation measurements.

Deep convection over Northern Italy: synoptic and thermodynamic analysis

NASA Astrophysics Data System (ADS)

Costa, S.; Mezzasalma, P.; Levizzani, V.; Alberoni, P. P.; Nanni, S.

Synoptic and thermodynamic characteristics of severe storm outbreaks, including supercells, over northern Italy's Po valley are examined over a 3-year period. Storms are divided into three main categories according to the most relevant associated ground phenomenon: tornado-like, hailfall and heavy rain. For each category, the most common synoptic characteristics are investigated. Sounding data are used to calculate stability indices that help define the storm's environment. Results indicate that the interaction between the synoptic flow and the steep Alpine orography is the key factor responsible for building up the mesoscale circulation that leads to different kinds of severe storms. Some of the stability indices can be regarded as predictors of intense convection.

The role of ice particles in the microphysics and dynamics of deep convective storms in various latitudes

NASA Astrophysics Data System (ADS)

Huang, Y. C.; Wang, P. K.

2017-12-01

The role of ice particles in the microphysics and dynamics of deep convective storms in various latitudes Yi-Chih Huang and Pao K. Wang Ice particles contribute to the microphysics and dynamics of severe storms in various regions of the world to a degree that is not commonly recognized. This study is motivated by the need to understand the role of ice particles plays in the development of severe storms so that their impact on various aspects of the storm behavior can be properly assessed. In this study, we perform numerical simulations of thunderstorms using a cloud resolving model WISCDYMM that includes parameterized microphysical processes to understand the role played by ice processes. We simulate thunderstorms occurred over various regions of the world including tropics, substropics and midlatitudes. We then perform statistical analysis of the simulated results to show the formation of various categories of hydrometeors to reveal the importance of ice processes. We will show that ice hydrometeors (cloud ice, snow, graupel/hail) account for 80% of the total hydrometeor mass for the High Plains storms but 50% for the subtropical storms. In addition, the melting of large ice particles (graupel and hail) is the major production process of rain in tropical storms although the ratio of ice-phase mass is responsible for only 40% of the total hydrometeor mass. Furthermore, hydrometeors have their own special microphysical processes in development and depletion over various latitudes. Microphysical structures depend on atmospheric dynamical and thermodynamical conditions which determine the partitioning of hydrometeors. This knowledge would benefit the microphysics parameterization in cloud models and cumulus parameterization in global circulation models.

Erosion on very stony forest soil during phenomenal rain in Webster County, West Virginia

Treesearch

J. H. Patric; W. E., Jr. Kidd

1982-01-01

On July 15 and 16, 1979, at least 6 inches of rain fell in central West Virginia during 3 hours, a storm of return period longer than 1,000 years. More than 6 miles of logging roads were examined for evidences of soil erosion and sediment delivery to streams. Erosion was negligible on very stony soils where (a) logging roads were litter covered, (b) road grades were...

Dual-polarization characteristics of the radar ocean return in the presence of rain

NASA Technical Reports Server (NTRS)

Meneghini, R.; Kumagai, H.; Kozu, T.

1992-01-01

Experimental data are presented on the polarimetric and dual-wavelength characteristics of the ocean surface in the presence of rain. To explain a portion of the variability observed in scatter plots under rain conditions, a storm model is used that incorporates measured drop size distributions. The fairly large variability indicates that effects of drop size distribution and the presence of partially melted particles can introduce a significant error in the estimate of attenuation. This effect is especially significant in the case of a 10-GHz radar under high rain rates. A surface reference method at this frequency will tend to overestimate the rain attenuation unless melting layer attenuation is properly taken into account. Observations of the cross-polarization return in stratiform rain over an ocean surface show three distinct components. Two of these correspond to aspherical, nonaligned particles in the melting layer seen in the direct and mirror-image returns. The remaining part depends both on the off-nadir depolarization by the surface and on the rain medium. A possible mechanism for this latter effect is the bistatic scattering from the rain to the surface.

KSC-08pd2502

NASA Image and Video Library

2008-08-23

CAPE CANAVERAL, Fla. – This aerial view shows the high water surrounding Launch Pad 39A at NASA's Kennedy Space Center following Tropical Storm Fay. In the foreground is the Atlantic Ocean. The storm passed over the center Aug. 20 and then stalled offshore, bringing with it heavy rain and tropical storm force wind. Kennedy closed Aug. 19 because of Fay and reopened for normal operations Aug. 22. Based on initial assessments, there was no damage to space flight hardware, such as the space shuttles and Hubble Space Telescope equipment. Some facilities did sustain minor damage. Photo credit: NASA/Amanda Diller

KSC-08pd2427

NASA Image and Video Library

2008-08-21

CAPE CANAVERAL, Fla. – The median of one of the roads on NASA's Kennedy Space Center is flooded from Tropical Storm Fay. An emergency vehicle illustrates the flooding on the road as well. The storm passed over the center Aug. 20 and then stalled offshore, bringing with it heavy rain and tropical storm force wind. Kennedy closed Aug. 19 because of Fay and reopened for normal operations Aug. 22. Based on initial assessments, there was no damage to space flight hardware, such as the space shuttles and Hubble Space Telescope equipment. Some facilities did sustain minor damage. Photo credit: NASA/Jack Pfaller

KSC-08pd2503

NASA Image and Video Library

2008-08-23

CAPE CANAVERAL, Fla. – Launch Pad 39A seems to be an island in the high water surrounding it caused by Tropical Storm Fay. In the distance is the Atlantic Ocean. The storm passed over the center Aug. 20 and then stalled offshore, bringing with it heavy rain and tropical storm force wind. Kennedy closed Aug. 19 because of Fay and reopened for normal operations Aug. 22. Based on initial assessments, there was no damage to space flight hardware, such as the space shuttles and Hubble Space Telescope equipment. Some facilities did sustain minor damage. Photo credit: NASA/Amanda Diller

GOES-West Satellite Eyes Soggy Storm Approaching California

NASA Image and Video Library

2014-02-28

A swirling Eastern Pacific Ocean storm system headed for California was spotted by NOAA's GOES-West satellite on February 28. According to the National Weather Service, this storm system has the potential to bring heavy rainfall to the drought-stricken state. The storm was captured using visible data from NOAA's GOES-West or GOES-15 satellite on Feb. 28 at 1915 UTC/11:15 a.m. PST was made into an image by NASA/NOAA's GOES Project at NASA's Goddard Space Flight Center in Greenbelt, Md. The storm's center appeared as a tight swirl, with bands of clouds and showers already sweeping over the state extending from northern California to Baja California, Mexico. At 11:30 a.m. PST on February 28, Bill Patzert, climatologist at NASA's Jet Propulsion Laboratory in Pasadena, Calif. said, "Right now from northern to southern California we are being battered by very heavy rain, strong winds and our coastal communities are being battered by high surf. Through the weekend we are bracing for mud and rock slides in areas that recently burned [from wildfires]. Flooding is looming up and down the state." The National Weather Service (NWS) serving Los Angeles posted a Flood Watch for the region on Friday, February 28. The Flood Watch notes the "potential for flash flooding and debris flows for some 2013 and 2014 burn areas in Los Angeles County from this morning through Saturday evening (March 1).” The NWS Flood Watch also noted "a very strong and dynamic storm will bring a significant amount of rain to much of southwestern California through Saturday evening. A flash flood watch has been issued for several recent burn areas in Los Angeles County due to the abundant rainfall expected. Rain rates at times are expected to range from a half inch to one inch per hour which could cause significant mud and debris flows. There will be a chance of thunderstorms with locally higher rainfall rates." "Californians haven't seen rain and wind this powerful in 3 years," Patzert said. "By early next week, as this system moves east, this powerful system will wreak havoc causing snow and ice storms through the Midwest into the Northeast." GOES satellites provide the kind of continuous monitoring necessary for intensive data analysis. Geostationary describes an orbit in which a satellite is always in the same position with respect to the rotating Earth. This allows GOES to hover continuously over one position on Earth's surface, appearing stationary. As a result, GOES provide a constant vigil for the atmospheric "triggers" for severe weather conditions such as tornadoes, flash floods, hail storms and hurricanes. On a positive note, Patzert noted, "This is a nice down payment on drought recovery in the parched Western U.S." For updated information about the storm system, visit NOAA's National Weather Service website: www.weather.gov For more information about GOES satellites, visit: www.goes.noaa.gov/ or goes.gsfc.nasa.gov/ Rob Gutro NASA's Goddard Space Flight Center NASA image use policy. NASA Goddard Space Flight Center enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission. Follow us on Twitter Like us on Facebook Find us on Instagram

Winds, Water Budgets and Stable Isotopes in Tropical Cyclones using TRMM and QUICKSCAT

NASA Technical Reports Server (NTRS)

Lawrence, James R.

2004-01-01

Water vapor is the most abundant greenhouse gas in the atmosphere. Changes in its concentration and distribution are controlled by the hydrologic cycle. Because of its capacity to absorb and emit long wave radiation, release latent heat during condensation in storms and reflect short wave radiation when clouds form it has a major impact on Global climate change. The stable isotope ratios of water are H20 H2l6O and H0 H2l6O. These ratios change whenever water undergoes a phase change. They also change in both rain and water vapor whenever an air parcel is exposed to rain. In addition the relative changes in the two ratios differ as a &nction of the relative humidity. In short, the stable isotope ratios in water vapor in the atmosphere contain an integrated history of the processes affecting the concentration and distribution of water vapor in the atmosphere. Therefore the measurement and interpretation of changes in these stable isotope ratios are a powerful tool matched by no other method in tracing the transport history of water in the atmosphere. Our initial studies under this grant focused on the changes of the stable isotope ratios of precipitation and water vapor in tropical cyclones. The changes in time and space were found to be very large and to trace the transport of water in the storms reflecting changes in basic structural features. Because the stable isotope ratios of rains from tropical cyclones are so low flooding associated with land falling tropical cyclones introduces a negative isotopic spike into the coastal surface waters. In addition the stable isotope ratios of water vapor in the vicinity of tropical cyclones is anomalously low. This suggests that carbonate shelled organisms such as ostracoda living in coastal waters have the potential to record the isotopic spike and thereby provide a long term record of tropical storm activity in sediment cores containing fossil shells. Likewise, tree rings in coastal environments offer a similar potential. We have analyzed the oxygen isotopic composition of ostrcoda shells formed in the floodwaters of Tropical Storm Allison (2001) and discovered the negative isotopic 1 16 spike. Because we had learned that storm activity has a major impact on the stable isotope ratios of water vapor in the tropics and sub-tropics we decided to analyze the isotopic compositions of water vapor in different locations in the tropics. We did this in Puerto Escondido, Mexico in July 1998, near Kwajalein Island in the Pacific in 1999 as part of a TRMM summer field program and in 2001 in Key West, Florida as part of the CAMEX 4 summer field program. Our isotopic studies along with our earlier tropical cyclone studies showed that the low isotopic ratios in water vapor induced by exposure to rains the storms persisted for 48 hours often far away from the original storm site. We also noted that positive isotopic spikes were introduced into atmospheric water vapor if winds were high and extensive sea spray was present. These findings have a significant impact on the interpretation of the stable isotope studies of tropical ice cores found in the high mountain regions of the tropics. The assumption made in interpreting the ice core record is that the source water vapor evaporated from the sea surface is in near isotopic equilibrium with the seawater and undergoes a decrease during its transport that reflects the change in temperature from the sea surface to the site of the ice core. Because an additional isotopic depletion occurs at the sea surface source area that depends on the intensity, duration and size of the tropical rain system the isotopic variations found in the ice cores must take into account changes in past storm activity in the tropics. These systems must be an important source of water vapor to the ice cores because they charge the troposphere with water vapor to a far greater vertical height than evaporation in quiescent regions. Finally, an interest in increased heat transfer in thnterior of tropical cyclones resulting from greater amounts of sea spray is a topic of considerable interest to the research community. Increases in sea spray may be related to rapid changes in the intensity of hurricanes, a feature of hurricanes that currently is very poorly forecast. Project CBLAST of the Hurricane Research Division of NOAA is an active program that uses P3 research aircraft to evaluate this problem. An instrument has been designed and built at the University of Houston that will be placed on the P3 research aircraft during the 2004 hurricane season. It continuously measures the salt content of rain in hurricanes. Changes in the salt content of the rains should reflect the abundance of sea spray at the sea surface. In this way maps of sea spray intensity in hurricanes may be forthcoming. This should help computer modelers who simulate hurricanes to better understand the potential of changes in sea spray to change the intensity of hurricanes. The cost of designing, building and installing this instrument was borne largely by funding from this NASA grant. A list of presentations at national meetings and publications that were as the result of funding from this NASA grant are found in the report.

Identifying recharge from tropical cyclonic storms, Baja California Sur, Mexico.

PubMed

Eastoe, Christopher J; Hess, Greg; Mahieux, Susana

2015-04-01

Groundwater in the Todos Santos watershed in southern Baja California, and throughout the peninsula south of latitude 28°N, has values of (δ18 O‰, δD‰) ranging between (-8.3, -57) and (-10.9, -78). Such negative values are uncharacteristic of the site latitude near the sea level. Altitude effects do not explain the isotope data. Tropical depressions originating along the Pacific coast of North America yield rain with isotopic depletion; rain from these weather systems in southern Arizona commonly has δ18O values<-10‰ in comparison with amount-weighted mean summer and fall rain at -6‰. Isotope data indicate hurricane rain as the predominant source of recharge in southern Baja California, where named tropical depressions bring large rains (>50 mm) at least once every 2 to 3 years, and along the Pacific coast between Jalisco and Oaxaca. © 2014, National Ground Water Association.

Optical Extinction Measurements of Laser Side-Scatter During Tropical Storm Colin

NASA Technical Reports Server (NTRS)

Lane, John E.; Kasparis, Takis; Metzger, Philip; Michaelides, Silas

2017-01-01

A side-scatter imaging (SSI) technique using a 447 nm, 500 mW laser and a Nikon D80 camera was tested at Kennedy Space Center, Florida during the passing of a rain band associated with Tropical Storm Colin. The June 6, 2016, 22:00 GMT rain event was intense but short-lived owing to the strong west-to-east advection of the rain band. An effort to validate the optical extinction measurement was conducted by setting up a line of three tipping rain gauges along an 80 m east-west path and below the laser beam. Differences between tipping bucket measurements were correlated to the extinction coefficient profile along the lasers path, as determined by the SSI measurement. In order to compare the tipping bucket to the optical extinction data, a Marshall-Palmer DSD model was assumed. Since this was a daytime event, the laser beam was difficult to detect in the camera images, pointing out an important limitation of SSI measurements: the practical limit of DSD density that can be effectively detected and analyzed under daylight conditions using this laser and camera, corresponds to a fairly moderate rainfall rate on the order of 20 mmh (night measurements achieve a much improved sensitivity). The SSI analysis model under test produced promising results, but in order to use the SSI method for routine meteorological studies, improvements to the math model will be required.

Volunteers build Bay St. Louis playground

NASA Image and Video Library

2005-12-17

More than 650 volunteers - many of them employees at NASA's Stennis Space Center - weathered rain and cold to transform Bay St. Louis' old City Park into a playground Dec. 17. Volunteers assembled and erected a slide, swing set, jungle gym, sand box and planter benches in an eight-hour time frame. The playground was the first new structure built in the town devastated by Hurricane Katrina and the first on the Gulf Coast after the storm. The project was financed and led by nonprofit organization KaBOOM!, whose vision is to create a great place to play within walking distance of every child in America.

Volunteers build Bay St. Louis playground

NASA Technical Reports Server (NTRS)

2005-01-01

More than 650 volunteers - many of them employees at NASA's Stennis Space Center - weathered rain and cold to transform Bay St. Louis' old City Park into a playground Dec. 17. Volunteers assembled and erected a slide, swing set, jungle gym, sand box and planter benches in an eight-hour time frame. The playground was the first new structure built in the town devastated by Hurricane Katrina and the first on the Gulf Coast after the storm. The project was financed and led by nonprofit organization KaBOOM!, whose vision is to create a great place to play within walking distance of every child in America.

Observations of C-band Brightness Temperatures and Ocean Surface Wind Speed and Rain Rate from the Hurricane Imaging Radiometer (HIRAD)

NASA Technical Reports Server (NTRS)

Miller, Timothy L.; James, M. W.; Roberts, J. B.; Jones, W. L.; May, C.; Ruf, C. S.; Uhlhorn, E. W.; Atlas, R.; Black, P.

2012-01-01

HIRAD flew on the WB-57 over Earl and Karl during NASA s GRIP (Genesis and Rapid Intensification Processes) campaign in August - September of 2010. HIRAD is a new Cband radiometer using a synthetic thinned array radiometer (STAR) technology to obtain cross-track resolution of approximately 3 degrees, out to approximately 60 degrees to each side of nadir. (The resulting swath width for a platform at 60,000 feet is roughly 60 km, and resolution for most of the swath is around 2 km.) By obtaining measurements of emissions at 4, 5, 6, and 6.6 GHz, observations of ocean surface wind speed and rain rate can be retrieved. This technique has been used for many years by precursor instruments, including the Stepped Frequency Microwave Radiometer (SFMR), which has been flying on the NOAA and USAF hurricane reconnaissance aircraft for several years to obtain observations within a single footprint at nadir angle. Results from the flights during the GRIP campaign will be shown, including images of brightness temperatures, wind speed, and rain rate. Comparisons will be made with observations from other instruments on the GRIP campaign, for which HIRAD observations are either directly comparable or are complementary. Features such as storm eye and eyewall, location of storm wind and rain maxima, and indications of dynamical features such as the merging of a weaker outer wind/rain maximum with the main vortex may be seen in the data. Potential impacts on operational ocean surface wind analyses and on numerical weather forecasts will also be discussed.

Structure of the Highly Sheared Tropical Storm Chantal During CAMEX-4

NASA Technical Reports Server (NTRS)

2004-01-01

Tropical Storm Chantal during August 2001 was a storm that failed to intensify over the few days prior to making landfall on the Yucatan Peninsula. An observational study of Tropical Storm Chantal is presented using a diverse data set including remote and in situ measurements from the NASA ER-2 and DC-8 and the NOAA WP-3D N42RF aircraft and satellite data. The authors discuss the storm structure from the larger scale environment down to the convective scale. Large vertical shear (850-200 hPa shear magnitude range 8-15 m/s) plays a very important role in preventing Chantal from intensifying. The storm had a poorly defined vortex that only extended up to 5-6 km altitude, and an adjacent intense convective region that comprised an MCS. The entire low-level circulation center was in the rain-free western side of the storm, about 80 km to the west-southwest of the MCS. The MCS appears to have been primarily the result of intense convergence between large-scale, low-level easterly flow with embedded downdrafts, and the cyclonic vortex flow. The individual cells in the MCS such as Cell 2 during the period of the observations, were extremely intense with reflectivity core diameters of 10 km and peak updrafts exceeding 20 m/s. Associated with this MCS were two broad subsidence (warm) regions both of which had portions over the vortex. The first layer near 700 hPa was directly above the vortex and covered most of it. The second layer near 500 hPa was along the forward and right flanks of Cell 2 and undercut the anvil divergence region above. There was not much resemblance of these subsidence layers to typical upper level warm cores in hurricanes that are necessary to support strong surface winds and a low central pressure. The observations are compared to previous studies of weakly sheared storms and modeling studies of shear effects and intensification. Additional information is included in the original extended abstract.

Radar-rain-gauge rainfall estimation for hydrological applications in small catchments

NASA Astrophysics Data System (ADS)

Gabriele, Salvatore; Chiaravalloti, Francesco; Procopio, Antonio

2017-07-01

The accurate evaluation of the precipitation's time-spatial structure is a critical step for rainfall-runoff modelling. Particularly for small catchments, the variability of rainfall can lead to mismatched results. Large errors in flow evaluation may occur during convective storms, responsible for most of the flash floods in small catchments in the Mediterranean area. During such events, we may expect large spatial and temporal variability. Therefore, using rain-gauge measurements only can be insufficient in order to adequately depict extreme rainfall events. In this work, a double-level information approach, based on rain gauges and weather radar measurements, is used to improve areal rainfall estimations for hydrological applications. In order to highlight the effect that precipitation fields with different level of spatial details have on hydrological modelling, two kinds of spatial rainfall fields were computed for precipitation data collected during 2015, considering both rain gauges only and their merging with radar information. The differences produced by these two precipitation fields in the computation of the areal mean rainfall accumulation were evaluated considering 999 basins of the region Calabria, southern Italy. Moreover, both of the two precipitation fields were used to carry out rainfall-runoff simulations at catchment scale for main precipitation events that occurred during 2015 and the differences between the scenarios obtained in the two cases were analysed. A representative case study is presented in detail.

Microphysical Retrievals Over Stratiform Rain Using Measurements from an Airborne Dual-Wavelength Radar-Radiometer

NASA Technical Reports Server (NTRS)

Meneghini, Robert; Kumagai, Hiroshi; Wang, James R.; Iguchi, Toshio; Kozu, Toshiaki

1997-01-01

The need to understand the complementarity of the radar and radiometer is important not only to the Tropical Rain Measuring Mission (TRMM) program but to a growing number of multi-instrumented airborne experiment that combine single or dual-frequency radars with multichannel radiometers. The method of analysis used in this study begins with the derivation of dual-wavelength radar equations for the estimation of a two-parameter drop size distribution (DSD). Defining a "storm model" as the set of parameters that characterize snow density, cloud water, water vapor, and features of the melting layer, then to each storm model there will usually correspond a set of range-profiled drop size distributions that are approximate solutions of the radar equations. To test these solutions, a radiative transfer model is used to compute the brightness temperatures for the radiometric frequencies of interest. A storm model or class of storm models is considered optimum if it provides the best reproduction of the radar and radiometer measurements. Tests of the method are made for stratiform rain using simulated storm models as well as measured airborne data. Preliminary results show that the best correspondence between the measured and estimated radar profiles usually can be obtained by using a moderate snow density (0.1-0.2 g/cu cm), the Maxwell-Garnett mixing formula for partially melted hydrometeors (water matrix with snow inclusions), and low to moderate values of the integrated cloud liquid water (less than 1 kg/sq m). The storm-model parameters that yield the best reproductions of the measured radar reflectivity factors also provide brightness temperatures at 10 GHz that agree well with the measurements. On the other hand, the correspondence between the measured and modeled values usually worsens in going to the higher frequency channels at 19 and 34 GHz. In searching for possible reasons for the discrepancies, It is found that changes in the DSD parameter Mu, the radar constants, or the path-integrated attenuation can affect the high frequency channels significantly. In particular, parameters that cause only modest increases in the median mass diameter of the snow, and which have a minor effect on the radar returns or the low frequency brightness temperature, can produce a strong cooling of the 34 GHz brightness temperature.

Series of Storms Battering California Tracked by NASA AIRS Instrument

NASA Image and Video Library

2017-01-13

A series of atmospheric rivers that brought drought-relieving rains, heavy snowfall and flooding to California this week is highlighted in a new movie created with satellite data from the Atmospheric Infrared Sounder (AIRS) instrument on NASA's Aqua satellite. The images of atmospheric water vapor were collected by AIRS between January 7 and 11. They show the amount of moisture present in the atmosphere and its movement across the Pacific Ocean to the United States, where much of it fell as rain or snow. In early January 2017, the Western U.S. experienced rain and flooding from a series of storms flowing to America on multiple streams of moist air, each individually known as an atmospheric river. Atmospheric rivers are typically 250 to 375 miles (400 to 600 kilometers) wide. The term "Pineapple Express" refers to atmospheric rivers that originate near or just east of the Hawaiian Islands and terminate along the West Coast of North America. Other atmospheric rivers originate in the tropical Western Pacific Ocean and take on a more west-to-east orientation near the U.S. West Coast. Several distinct plumes of moisture are apparent in the AIRS imagery. The first of three atmospheric river events occurred on January 7 and 8. This was a classic Pineapple Express, featuring an uninterrupted supply of heavy moisture drawn up from the deep tropics. This was the wettest storm of the series, producing very heavy rainfall, more than 1 foot (0.3 meter), in parts of Central and Northern California, with relatively smaller amounts of snow at the highest elevations of the Sierra Nevada. The second blob of heavy moisture, from January 8 to 10 to the west of California, likely originated thousands of miles to the west, in the tropical Western Pacific. This atmospheric river did not maintain its tropical connection. However, it still produced prodigious rainfall totals in Northern California and much more snow than the first event, since the storm had a more northern and colder trajectory. A third storm, the coldest of the three events, moved through California on January 11 and 12, producing significant rainfall, as well as snow at higher elevations. The movie ends with another atmospheric river attempting to form on January 11 and 12 to the west of Hawaii, transporting moisture into the storm track. Movies are availalbe at http://photojournal.jpl.nasa.gov/catalog/PIA21209

Wildfires and storms: Increased vulnerability of water quality in the southwestern U.S. in the face of climate change

NASA Astrophysics Data System (ADS)

Murphy, S. F.; Writer, J. H.; McCleskey, R. B.; Martin, D. A.

2014-12-01

Communities in the southwestern U.S. rely on forested watersheds to provide high-quality water, but these watersheds are prone to major disturbance by wildfire. The loss of vegetation and litter can decrease water storage and infiltration and decrease nutrient uptake, leading to enhanced surface runoff, erosion, and nutrient export compared to undisturbed watersheds. Post-wildfire impacts on water quality vary widely across geographic regions, and are largely driven by post-fire storm timing and intensity. In the southwestern U.S., the North American Monsoon can produce high-intensity rain from July through September. A better understanding of the post-fire water-quality response of watersheds to monsoonal storms in this region is therefore critical. The Fourmile Canyon Fire burned 2600 ha near Boulder, Colorado in September 2010, including 23% of the Fourmile Creek watershed. This watershed had been recovering from historical mining activity, and dispersed waste rock and mine tailings were only partially revegetated before the wildfire. We collected water quality, hydrological, and meteorological data with high temporal and spatial density upstream and downstream of the burned area for 4 years post-fire. For 9 months post-fire, the area received snow or low-intensity rain, and the difference in stream water chemistry between burned and unburned watersheds was minimal. However, in the summer of 2011, and in the following two summers, relatively common monsoonal storms caused dramatic, but short-lived, increases in discharge, sediment, nitrate, dissolved organic carbon, and metals downstream of the burned area. Such pulses can degrade aquatic ecosystems, impair water treatability, and decrease reservoir capacity. Climate change is projected to increase wildfire frequency and size and lead to an earlier and longer wildfire season. Simultaneously, storm frequency and intensity are predicted to increase, and the monsoon season may occur later in the year, potentially decreasing the average length of time between wildfire and subsequent high-intensity rain events. This suggests that substantial water-quality impacts may be more common in the future, resulting in a new paradigm for water treatment in the southwestern U.S.

Climatic Events and Historical Disturbances Control Acute and Chronic Water-Quality Impairment After Wildfire

NASA Astrophysics Data System (ADS)

Murphy, S. F.; Martin, D. A.; McCleskey, R. B.; Writer, J. H.

2016-12-01

Many studies have shown that surface water quality can be impaired after wildfire. The majority of these studies are typically conducted for short periods (1-2 years), and until recently, usually employed routine (fixed-interval) sampling. We monitored stream water quality for five years after a wildfire in the Colorado Front Range using a combination of routine sampling, storm sampling, and continuous sensors. This five-year study facilitated the measurement of post-wildfire water-quality response to a number of climatic events, including low- to moderate-intensity rain storms, drought, extreme rainfall (based on amount of rain that fell in a 7-day period), and the highest spring runoff recorded from the watershed during 23 years of record. Post-wildfire water quality was controlled by the hydrologic response to these climatic events, and by a legacy of historical disturbance from mining and related activities. Increased surface runoff during rain storms led to mobilization of sediment from hillslopes to stream channels. The sediment remained in stream channels during a drought that led to reduced (25% of mean) spring runoff, but this sediment, and associated constituents such as dissolved organic carbon and manganese, were remobilized into the water column and transported downstream during sustained high-flow spring runoff in the third year. We infer that the relative proportions of surface and subsurface runoff were altered by the wildfire and during the extreme rainfall, possibly leading to greater flow through abandoned mine adits and tunnels, and thus causing increased instream metal concentrations (such as arsenic and manganese). Post-wildfire water-quality issues were both acute, with significant water-quality impairment during storm events, and chronic, with elevated concentrations of sediment, nitrate, dissolved organic carbon, manganese, and arsenic for months to years after the wildfire. Such variable source water quality, in both contaminant type and concentration, presents a substantial challenge to water-treatment facilities. Climate change is projected to increase wildfire risk and possibly storm frequency and intensity, and thus the risk of wildfire impacts on water supplies is likely to worsen in the future.

Systematic Anomalies in Rainfall Intensity Estimates Over the Continental U.S.

NASA Technical Reports Server (NTRS)

Amitai, Eyal; Petersen, Walter Arthur; Llort, Xavier; Vasiloff, Steve

2010-01-01

Rainfall intensities during extreme events over the continental U.S. are compared for several advanced radar products. These products include: 1) TRMM spaceborne radar (PR) near surface estimates; 2) NOAA Next-Generation Quantitative Precipitation Estimation (QPE) very high-resolution (1 km) radar-only national mosaics (Q2); 3) very high-resolution instantaneous gauge adjusted radar national mosaics, which we have developed by applying gauge correction on the Q2 instantaneous radar-only products; and 4) several independent C-band dual-polarimetric radar-estimated rainfall samples collected with the ARMOR radar in northern Alabama. Though accumulated rainfall amounts are often similar, we find the satellite and the ground radar rain rate pdfs to be quite different. PR pdfs are shifted towards lower rain rates, implying a much larger stratiform/convective rain ratio than do ground radar products. The shift becomes more evident during strong continental convective storms and much less during tropical storms. Resolving the continental/maritime regime behavior and other large discrepancies between the products presents an important challenge. A challenge to improve our understanding of the source of the discrepancies, to determine the uncertainties of the estimates, and to improve remote-sensing estimates of precipitation in general.

Feasibility Report on Navigation Improvements for Mexico Beach Inlet, Mexico Beach, Florida.

DTIC Science & Technology

1989-03-01

result from frontal passages in which rain generally lasts the duration of the storm. The area is subject to tropical hurricanes, particularly in late...the city had restored the channel to pre-hurricane conditions, Hurricane/ Tropical Storm Juan again shoaled the channel severely on 31 October 1985...general geology in the vicinity of Mexico Beach is coastal lowlands which has forested rolling hills in the interior and fine sand beaches along the coast

Temporal and spatial variability of rainfall pH

Treesearch

Richard G. Semonin

1977-01-01

The distribution of average rainwater pH over an area of 1,800 km² containing 81 collectors was determined from 25 storm events. The areal average of the data was pH 4.9, with a range of values from 4.3 to 6.8. A single storm event was studied to determine the change of pH as a function of time. The initial rain was pH 7.1, decreasing to 4.1. An excellent...

ScienceCast 135: Follow the Water

NASA Image and Video Library

2014-02-21

NASA and JAXA launched a new satellite that can see through storms, tracking rain and snow around the globe better than any previous observatory. The Global Precipitation Measurement Core Observatory lifted off from Japan on Feb. 27th

Summary of Natural Hazard Statistics for 2017 in the United States

MedlinePlus

... Damage Costs Weather Event Convection Lightning Tornado Thunderstorm Wind Hail Extreme Temperatures Cold Heat Flood Flash Flood ... Drought Dust Storm Dust Devil Rain Fog High Wind Waterspout Fire Weather Mud Slide Volcanic Ash Miscellaneous ...

78 FR 55770 - West Virginia Disaster #WV-00032

Federal Register 2010, 2011, 2012, 2013, 2014

2013-09-11

... Administrative declaration of a disaster for the State of West Virginia dated 08/29/2013. Incident: Severe Storms and Heavy Rain. Incident Period: 06/12/2013 through 06/19/2013. Effective Date: 08/29/2013. Physical...

Summary of Natural Hazard Statistics for 2015 in the United States

MedlinePlus

... Damage Costs Weather Event Convection Lightning Tornado Thunderstorm Wind Hail Extreme Temperatures Cold Heat Flood Flash Flood ... Drought Dust Storm Dust Devil Rain Fog High Wind Waterspout Fire Weather Mud Slide Volcanic Ash Miscellaneous ...

Storm-centric view of Tropical Cyclone oceanic wakes

NASA Astrophysics Data System (ADS)

Gentemann, C. L.; Scott, J. P.; Smith, D.

2012-12-01

Tropical cyclones (TCs) have a dramatic impact on the upper ocean. Storm-generated oceanic mixing, high amplitude near-inertial currents, upwelling, and heat fluxes often warm or cool the surface ocean temperatures over large regions near tropical cyclones. These SST anomalies occur to the right (Northern Hemisphere) or left (Southern Hemisphere) of the storm track, varying along and across the storm track. These wide swaths of temperature change have been previously documented by in situ field programs as well as IR and visible satellite data. The amplitude, temporal and spatial variability of these surface temperature anomalies depend primarily upon the storm size, storm intensity, translational velocity, and the underlying ocean conditions. Tropical cyclone 'cold wakes' are usually 2 - 5 °C cooler than pre-storm SSTs, and persist for days to weeks. Since storms that occur in rapid succession typically follow similar paths, the cold wake from one storm can affect development of subsequent storms. Recent studies, on both warm and cold wakes, have mostly focused on small subsets of global storms because of the amount of work it takes to co-locate different data sources to a storm's location. While a number of hurricane/typhoon websites exist that co-locate various datasets to TC locations, none provide 3-dimensional temporal and spatial structure of the ocean-atmosphere necessary to study cold/warm wake development and impact. We are developing a global 3-dimensional storm centric database for TC research. The database we propose will include in situ data, satellite data, and model analyses. Remote Sensing Systems (RSS) has a widely-used storm watch archive which provides the user an interface for visually analyzing collocated NASA Quick Scatterometer (QuikSCAT) winds with GHRSST microwave SSTs and SSM/I, TMI or AMSR-E rain rates for all global tropical cyclones 1999-2009. We will build on this concept of bringing together different data near storm locations when developing the storm-centric database. This database will be made available to researchers via the web display tools previously developed for RSS web pages. The database will provide scientists with a single data format collection of various atmospheric and oceanographic data, and will include all tropical storms since 1998, when the passive MW SSTs from the TMI instrument first became available. Initial results showing an analysis of Typhoon Man-Yi will be presented.

Winter Storm Continues Across Central U.S.

NASA Image and Video Library

2013-12-06

The powerful winter storm that has been affecting much of the central and western U.S. continues to intensify as it moves into Canada. Snow is tapering off across the Upper Midwest, but heavy snow is possible on Thursday from the Ohio Valley to the mid-Mississippi Valley, with heavy rain possible from the central Appalachians to the lower Mississippi Valley. Freezing rain is possible from Texas to the Ohio Valley. This image was taken by GOES East at 1745Z on December 5, 2013. Credit: NOAA/NASA GOES Project Caption: NOAA NASA image use policy. NASA Goddard Space Flight Center enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission. Follow us on Twitter Like us on Facebook Find us on Instagram

The burrowing activity of scorpions ( Scorpio maurus palmatus) and their potential contribution to the erosion of Hamra soils in Karkur, central Israel

NASA Astrophysics Data System (ADS)

Rutin, J.

1996-03-01

The burrowing activity of the scorpion Scorpio maurus palmatus was studied on a 1200 m 2 slope of a so-called "Hamra" sandy soil in Karkur, Israel. The main results were (1) The scorpions excavate soil material after rain storms, preparing this material for erosion processes by rain splash and rainwash. (2) The burrowing activity stops in the dry summer and during cold days of the winter. This means that Scorpio Maurus Palmatus is preparing soil for erosion from one storm to the next, and not from one season to the next as was previously thought. Further, it was found that the amount of soil material excavated from the burrow is proportional to the size of the scorpion and that most of the mounds were deposited toward the upper part of the slope which means that part is washed back into the burrow itself.

Explicit prediction of hail using multimoment microphysics schemes for a hailstorm of 19 March 2014 in eastern China

NASA Astrophysics Data System (ADS)

Luo, Liping; Xue, Ming; Zhu, Kefeng; Zhou, Bowen

2017-07-01

In the late afternoon of 19 March 2014, a severe hailstorm swept through eastern central Zhejiang province, China. The storm produced golf ball-sized hail, strong winds, and lighting, lasting approximately 1 h over the coastal city of Taizhou. The Advanced Regional Prediction System is used to simulate the hailstorm using different configurations of the Milbrandt-Yau microphysics scheme that predict one, two, or three moments of the hydrometeor particle size distribution. Simulated fields, including accumulated precipitation and maximum estimated hail size (MESH), are verified against rain gauge observations and radar-derived MESH, respectively. For the case of the 19 March 2014 storms, the general evolution is better predicted with multimoment microphysics schemes than with the one-moment scheme; the three-moment scheme produces the best forecast. Predictions from the three-moment scheme qualitatively agree with observations in terms of size and amount of hail reaching the surface. The life cycle of the hailstorm is analyzed, using the most skillful, three-moment forecast. Based upon the tendency of surface hail mass flux, the hailstorm life cycle can be divided into three stages: developing, mature, and dissipating. Microphysical budget analyses are used to examine microphysical processes and characteristics during these three stages. The vertical structures within the storm and their link to environmental shear conditions are discussed; together with the rapid fall of hailstones, these structures and conditions appear to dictate this pulse storm's short life span. Finally, a conceptual model for the life cycle of pulse hailstorms is proposed.

KSC-08pd2425

NASA Image and Video Library

2008-08-21

CAPE CANAVERAL, Fla. – A member of the "ride-out crew," a group of emergency personnel, at NASA's Kennedy Space Center monitors effects from Tropical Storm Fay. In the background is the Operations Support Building I in the Launch Complex 39 Area. The storm passed over the center Aug. 20 and then stalled offshore, bringing with it heavy rain and tropical storm force wind. Kennedy closed Aug. 19 because of Fay and reopened for normal operations Aug. 22. Based on initial assessments, there was no damage to space flight hardware, such as the space shuttles and Hubble Space Telescope equipment. Some facilities did sustain minor damage. Photo credit: NASA/Jack Pfaller

An assessment of the potential toxicity of runoff from an urban roadscape during rain events.

PubMed

Waara, Sylvia; Färm, Carina

2008-05-01

The potential negative impact of urban storm water on aquatic freshwater ecosystems has been demonstrated in various studies with different types of biological methods. There are a number of factors that influence the amount and bioavailability of contaminants in storm water even if it is derived from an area with a fairly homogenous land use such as a roadscape where a variation in toxicity during rain events might be expected. There are only a few previous investigations on the toxicity of highway runoff and they have not explored these issues extensively. The main objective of this study is therefore to characterize the potential toxicity of highway runoff during several rain events before it enters a detention pond in Västerås, Sweden, using laboratory bioassays with test organisms representing various functional groups in an aquatic ecosystem. The results are to be used for developing a monitoring program, including biological methods. The storm water was sampled before the entrance to a detention pond, which receives run-off from a highway with approximately 20,000 vehicles a day. The drainage area, including the roadscape and vegetated areas, is 4.3 ha in size. Samples for toxicity tests were taken with an automatic sampler or manually during storm events. In total, the potential toxicity of 65 samples representing 15 different storm events was determined. The toxicity was assessed with 4 different test organisms; Vibrio fischeri using the Microtox comparison test, Daphnia magna using Daphtoxkit-F agna, Thamnocephalus platyurus using the ThamnotoxkitF and Lemna minor, duckweed using SS 028313. Of the 65 samples, 58 samples were tested with DaphniatoxkitF agna, 57 samples with the Microtox comparison test, 48 samples with ThamnotoxkitF and 20 samples with Lemna minor, duckweed. None of the storm water samples were toxic. No toxicity was detected with the Lemna minor test, but in 5 of the 23 samples tested in comparison to the control a growth stimulation of 22-46% was observed. This is in accordance with the chemical analysis of the storm water, which indicated rather large concentrations of tot-N and tot-P. In addition to the growth stimulation, morphological changes were observed in all the 5 samples from the winter event that was sampled. The lack of toxicity observed in our study might be due to a lower traffic intensity (20,000 vehicles/day) at the site and the trapping of pollutants in the vegetated areas of the roadscape, resulting in much smaller loads of pollutants in the storm water than in some previous studies. Ecotoxicological evaluations of storm water including run off from rain events from urban roadscape studies clearly reveal that toxicity may or may not be detected depending upon site, storm condition and the test organism chosen. However, storm water might not be as polluted as previously reported nor may the first flush be such a widespread phenomenon as we originally expected. In this study, there was also a good correlation between pollutant load measured and the lack of toxicity. The test organisms chosen in this study are commonly used in effluent control programs in Sweden and other countries, which makes it possible to compare the results with those from other effluents. In this study, only acute toxicity tests were used and further studies using chronic toxicity tests, assays for genotoxic compounds or in situ bioassays might reveal biological effects at this site. Furthermore, most of the samples were taken in spring, summer or fall and it is possible that winter conditions might alter the constituents in the storm water and, thus, the toxicity of the samples. Considering the complex nature of run off from urban roadscapes, it will be virtually impossible to evaluate properly the potential hazard of particular storm water and the efficiency of a particular treatment strategy from only physical and chemical characterizations of the effluent. Therefore, despite the lack of toxicity detected in this study, it is recommended that toxicity tests or other biological methods should be included in evaluations of the effects of runoff from roadscapes.

Classification and evaluation of the documentary-recorded storm events in the Annals of the Choson Dynasty (1392-1910), Korea

NASA Astrophysics Data System (ADS)

Yoo, Chulsang; Park, Minkyu; Kim, Hyeon Jun; Choi, Juhee; Sin, Jiye; Jun, Changhyun

2015-01-01

In this study, the analysis of documentary records on the storm events in the Annals of the Choson Dynasty, covering the entire period of 519 years from 1392 to 1910, was carried out. By applying various key words related to storm events, a total of 556 documentary records could be identified. The main objective of this study was to develop rules of classification for the documentary records on the storm events in the Annals of the Choson Dynasty. The results were also compared with the rainfall data of the traditional Korean rain gauge, named Chukwooki, which are available from 1777 to 1910 (about 130 years). The analysis is organized as follows. First, the frequency of the documents, their length, comments about the size of the inundated area, the number of casualties, the number of property losses, and the size of the countermeasures, etc. were considered to determine the magnitude of the events. To this end, rules of classification of the storm events are developed. Cases in which the word 'disaster' was used along with detailed information about the casualties and property damages, were classified as high-level storm events. The high-level storm events were additionally sub-categorized into catastrophic, extreme, and severe events. Second, by applying the developed rules of classification, a total of 326 events were identified as high-level storm events during the 519 years of the Choson Dynasty. Among these high-level storm events, only 19 events were then classified as the catastrophic ones, 106 events as the extreme ones, and 201 events as the severe ones. The mean return period of these storm events was found to be about 30 years for the catastrophic events, 5 years for the extreme events, and 2-3 years for the severe events. Third, the classification results were verified considering the records of the traditional Korean rain gauge; it was found that the catastrophic events are strongly distinguished from other events with a mean total rainfall and a storm duration equal to 439.8 mm and 49.3 h, respectively. The return period of these catastrophic events was also estimated to be in the range 100-500 years.

The role of precipitation type, intensity, and spatial distribution in source water quality after wildfire

NASA Astrophysics Data System (ADS)

Murphy, Sheila F.; Writer, Jeffrey H.; Blaine McCleskey, R.; Martin, Deborah A.

2015-08-01

Storms following wildfires are known to impair drinking water supplies in the southwestern United States, yet our understanding of the role of precipitation in post-wildfire water quality is far from complete. We quantitatively assessed water-quality impacts of different hydrologic events in the Colorado Front Range and found that for a three-year period, substantial hydrologic and geochemical responses downstream of a burned area were primarily driven by convective storms with a 30 min rainfall intensity >10 mm h-1. These storms, which typically occur several times each year in July-September, are often small in area, short-lived, and highly variable in intensity and geographic distribution. Thus, a rain gage network with high temporal resolution and spatial density, together with high-resolution stream sampling, are required to adequately characterize post-wildfire responses. We measured total suspended sediment, dissolved organic carbon (DOC), nitrate, and manganese concentrations that were 10-156 times higher downstream of a burned area compared to upstream during relatively common (50% annual exceedance probability) rainstorms, and water quality was sufficiently impaired to pose water-treatment concerns. Short-term water-quality impairment was driven primarily by increased surface runoff during higher intensity convective storms that caused erosion in the burned area and transport of sediment and chemical constituents to streams. Annual sediment yields downstream of the burned area were controlled by storm events and subsequent remobilization, whereas DOC yields were closely linked to annual runoff and thus were more dependent on interannual variation in spring runoff. Nitrate yields were highest in the third year post-wildfire. Results from this study quantitatively demonstrate that water quality can be altered for several years after wildfire. Because the southwestern US is prone to wildfires and high-intensity rain storms, the role of storms in post-wildfire water-quality impacts must be considered when assessing water-quality vulnerability.

The role of precipitation type, intensity, and spatial distribution in source water quality after wildfire

USGS Publications Warehouse

Murphy, Sheila F.; Writer, Jeffrey H.; McCleskey, R. Blaine; Martin, Deborah A.

2015-01-01

Storms following wildfires are known to impair drinking water supplies in the southwestern United States, yet our understanding of the role of precipitation in post-wildfire water quality is far from complete. We quantitatively assessed water-quality impacts of different hydrologic events in the Colorado Front Range and found that for a three-year period, substantial hydrologic and geochemical responses downstream of a burned area were primarily driven by convective storms with a 30 min rainfall intensity >10 mm h−1. These storms, which typically occur several times each year in July–September, are often small in area, short-lived, and highly variable in intensity and geographic distribution. Thus, a rain gage network with high temporal resolution and spatial density, together with high-resolution stream sampling, are required to adequately characterize post-wildfire responses. We measured total suspended sediment, dissolved organic carbon (DOC), nitrate, and manganese concentrations that were 10–156 times higher downstream of a burned area compared to upstream during relatively common (50% annual exceedance probability) rainstorms, and water quality was sufficiently impaired to pose water-treatment concerns. Short-term water-quality impairment was driven primarily by increased surface runoff during higher intensity convective storms that caused erosion in the burned area and transport of sediment and chemical constituents to streams. Annual sediment yields downstream of the burned area were controlled by storm events and subsequent remobilization, whereas DOC yields were closely linked to annual runoff and thus were more dependent on interannual variation in spring runoff. Nitrate yields were highest in the third year post-wildfire. Results from this study quantitatively demonstrate that water quality can be altered for several years after wildfire. Because the southwestern US is prone to wildfires and high-intensity rain storms, the role of storms in post-wildfire water-quality impacts must be considered when assessing water-quality vulnerability.

Spatial interpolation of hourly precipitation and dew point temperature for the identification of precipitation phase and hydrologic response in a mountainous catchment

NASA Astrophysics Data System (ADS)

Garen, D. C.; Kahl, A.; Marks, D. G.; Winstral, A. H.

2012-12-01

In mountainous catchments, it is well known that meteorological inputs, such as precipitation, air temperature, humidity, etc. vary greatly with elevation, spatial location, and time. Understanding and monitoring catchment inputs is necessary in characterizing and predicting hydrologic response to these inputs. This is true all of the time, but it is the most dramatically critical during large storms, when the input to the stream system due to rain and snowmelt creates the potential for flooding. Besides such crisis events, however, proper estimation of catchment inputs and their spatial distribution is also needed in more prosaic but no less important water and related resource management activities. The first objective of this study is to apply a geostatistical spatial interpolation technique (elevationally detrended kriging) to precipitation and dew point temperature on an hourly basis and explore its characteristics, accuracy, and other issues. The second objective is to use these spatial fields to determine precipitation phase (rain or snow) during a large, dynamic winter storm. The catchment studied is the data-rich Reynolds Creek Experimental Watershed near Boise, Idaho. As part of this analysis, precipitation-elevation lapse rates are examined for spatial and temporal consistency. A clear dependence of lapse rate on precipitation amount exists. Certain stations, however, are outliers from these relationships, showing that significant local effects can be present and raising the question of whether such stations should be used for spatial interpolation. Experiments with selecting subsets of stations demonstrate the importance of elevation range and spatial placement on the interpolated fields. Hourly spatial fields of precipitation and dew point temperature are used to distinguish precipitation phase during a large rain-on-snow storm in December 2005. This application demonstrates the feasibility of producing hourly spatial fields and the importance of doing so to support an accurate determination of precipitation phase for assessing catchment hydrologic response to the storm.

A radar-based hydrological model for flash flood prediction in the dry regions of Israel

NASA Astrophysics Data System (ADS)

Ronen, Alon; Peleg, Nadav; Morin, Efrat

2014-05-01

Flash floods are floods which follow shortly after rainfall events, and are among the most destructive natural disasters that strike people and infrastructures in humid and arid regions alike. Using a hydrological model for the prediction of flash floods in gauged and ungauged basins can help mitigate the risk and damage they cause. The sparsity of rain gauges in arid regions requires the use of radar measurements in order to get reliable quantitative precipitation estimations (QPE). While many hydrological models use radar data, only a handful do so in dry climate. This research presents a robust radar-based hydro-meteorological model built specifically for dry climate. Using this model we examine the governing factors of flash floods in the arid and semi-arid regions of Israel in particular and in dry regions in general. The hydrological model built is a semi-distributed, physically-based model, which represents the main hydrological processes in the area, namely infiltration, flow routing and transmission losses. Three infiltration functions were examined - Initial & Constant, SCS-CN and Green&Ampt. The parameters for each function were found by calibration based on 53 flood events in three catchments, and validation was performed using 55 flood events in six catchments. QPE were obtained from a C-band weather radar and adjusted using a weighted multiple regression method based on a rain gauge network. Antecedent moisture conditions were calculated using a daily recharge assessment model (DREAM). We found that the SCS-CN infiltration function performed better than the other two, with reasonable agreement between calculated and measured peak discharge. Effects of storm characteristics were studied using synthetic storms from a high resolution weather generator (HiReS-WG), and showed a strong correlation between storm speed, storm direction and rain depth over desert soils to flood volume and peak discharge.

Aerosol Effects on Microphysical Processes, Storm Structure, and Cold Pool Strength in Simulated Supercell Thunderstorms from VORTEX-2 and VORTEX-SE

NASA Astrophysics Data System (ADS)

Guo, M.; Dawson, D. T., II; Baldwin, M. E.; Mansell, E. R.

2017-12-01

The cloud condensation nuclei (CCN) concentration has been found to strongly affect microphysical, dynamical and thermodynamical processes in supercells and other deep convective storms. Moreover, recent simulation studies have shown aerosols effects differ between higher- and lower-CAPE environments. Owing to the known sensitivity of severe storms to microphysical differences, studying the impact of aerosols supercell storms different environments is of clear societal importance. Tornadic environments in the southwastern U.S. are generally characterized by lower magnitudes CAPE and deeper tropospheric moisture than those in the Great Plains. These two regions were the focus of Verification of the Origins of Rotation in Tornadoes Experiment (VORTEX)-2 and VORTEX-Southeast (SE) field campaigns, respectively. In our study, we simulate several cases from VORTEX-2 and -SE with the Advanced Regional Prediction System (ARPS) Model at 6 different CCN concentrations (100-3000 cm-3). We use NSSL 3-moment microphysics parameterization schemeto explicitly predict precipitation particle size distributions and microphysirocess rates. Overall, storms under the higher-CAPE VORTEX-2 environments are more sensitiveto the change of CCN than those under the lower-CAPE VORTEX-SE environments. Updraft volume decreases as CCN increases for the VORTEX-2 cases, whereas the opposite is true but with a much weaker trend for the VORTEX-SE cases. Moreover, the cold pool strength drops dramatically as CCN surpasses 1000 cm-3n the VORTEX-2 cases but barely changes for the VORTEX-SE cases. Through a microphysics budget analysis, we show the change of the importance of ice processes is key to the differing sensitivities. in the VORTEX-2 cases, deposition to ice nuclei, cloud drop freezing and rain drop freezing in the upper levels (5-11km) contribute more to latent heating since more rain and cloud drops are lifted above the freezing level due to stronger updrafts. For CCN concentration over 1000cm-3, the drops become too small for efficient accretion by graupel and hail, leading to considerable decrease of latent heating and thus updraft volume. Finally, the decrease in cold pool strength in the VORTEX-2 cases at higher CCN is due to the rapid decrease of graupel melting at lower levels (<2km).

NASA Satellite Shows a Mean Irene Fury

NASA Image and Video Library

2011-08-28

This infrared image of Hurricane Irene from the AIRS instrument on NASA Aqua spacecraft, was taken at 2:47 a.m. EDT on Aug. 28. The storm coldest cloud top temperatures and intense rains are shown in purples and blues.

Floods, landslides and erosion from severe meteorological events in the Benevento Province, southern Italy.

NASA Astrophysics Data System (ADS)

Mascellaro, Neri; Guerriero, Luigi; Revellino, Paola; Grelle, Gerardo; Guadagno, Francesco M.

2017-04-01

As effect of the ongoing climate change, heavy meteorological events are increasing in frequency all over the world. The Campania Region in southern Italy is among the areas mostly affected by severe rainstorms and is periodically hit by their effect like floods and landslides. In October 2015, two intense rainfall events hit the central and southern regions of Italy but the most destructive effects occurred in the Benevento province (Campania region). The first storm, a self-healing V-shaped storm, began around at 7 p.m. of 14th October and stopped around at 3:00 a.m. of 15th October and was originated by the development of a cyclogenesis. The rain gages recorded a maximum cumulative value of 415.6 mm of rain in Paupisi (BN) and a strong increase in temperature; the maxima for the Benevento province was 24°C. The second storm began around at 12 a.m. of 19th October and stopped around at 7 p.m. of 20th October with a maximum cumulative value of 146.8 mm of rain in Colle Sannita(BN). These storms triggered a set of different effects that devastated more than 60 municipalities of the Sannio Province and were responsible for two casualties, €700 million of damage to infrastructures (estimates from Campania region) and about €1 billion damages to agriculture (Italian farmer Confederation). The the Calore river of the Benevento province and some of its tributaries overflowed destroying the surrounding area; major damages were recorded in the industrial area of the Benevento town. In the central and in the eastern sectors of the Benevento Province characterized by the outcropping of flyschoid units, the heavy rain triggered shallow earth flows, debris flows induced by rilling and soil slides. Debris avalanches and runoff-initiated debris flows reshaped the creeks of the Taburno-Camposauro massif and damaged a lot of infrastructure of the surrounding area. Flood events from the Calore river in the Benevento district have significant historical precedents. The most important events recorded in the past are: 1) the flood of the 2nd of October, 1949, that caused 20 fatalities, and 2) the flooding of May 1729. As first step of our study we reconstructed the spatial pattern and the temporal evolution of the storms affecting the Sannio area using the rainfall data recorded by the meteorological stations distributed across the Benevento Province. Subsequently we mapped all the effects to the landscape caused by the storms as: earth flows, soil slides, flooded area, runoff initiated debris flows and debris avalanches, debris flows initiated by rilling and soil erosion (using mainly Google earth images and field survey). We compered the location of these phenomena with the geological and topographic characteristics to understand likely controls in promote the triggering and the development of this unusual combination of different hazardous effects.

Sensitivity of a Cloud-Resolving Model to Bulk and Explicit Bin Microphysical Schemes. Part 2; Cloud Microphysics and Storm Dynamics Interactions

NASA Technical Reports Server (NTRS)

Li, Xiaowen; Tao, Wei-Kuo; Khain, Alexander P.; Simpson, Joanne; Johnson, Daniel E.

2009-01-01

Part I of this paper compares two simulations, one using a bulk and the other a detailed bin microphysical scheme, of a long-lasting, continental mesoscale convective system with leading convection and trailing stratiform region. Diagnostic studies and sensitivity tests are carried out in Part II to explain the simulated contrasts in the spatial and temporal variations by the two microphysical schemes and to understand the interactions between cloud microphysics and storm dynamics. It is found that the fixed raindrop size distribution in the bulk scheme artificially enhances rain evaporation rate and produces a stronger near surface cool pool compared with the bin simulation. In the bulk simulation, cool pool circulation dominates the near-surface environmental wind shear in contrast to the near-balance between cool pool and wind shear in the bin simulation. This is the main reason for the contrasting quasi-steady states simulated in Part I. Sensitivity tests also show that large amounts of fast-falling hail produced in the original bulk scheme not only result in a narrow trailing stratiform region but also act to further exacerbate the strong cool pool simulated in the bulk parameterization. An empirical formula for a correction factor, r(q(sub r)) = 0.11q(sub r)(exp -1.27) + 0.98, is developed to correct the overestimation of rain evaporation in the bulk model, where r is the ratio of the rain evaporation rate between the bulk and bin simulations and q(sub r)(g per kilogram) is the rain mixing ratio. This formula offers a practical fix for the simple bulk scheme in rain evaporation parameterization.

A Neighborhood-Scale Green Infrastructure Retrofit: Experimental Results, Model Simulations, and Resident Perspectives

NASA Astrophysics Data System (ADS)

Jefferson, A.; Avellaneda, P. M.; Jarden, K. M.; Turner, V. K.; Grieser, J.

2016-12-01

Distributed green infrastructure approaches to stormwater management that can be retrofit into existing development are of growing interest, but questions remain about their effectiveness at the watershed-scale. In suburban northeastern Ohio, homeowners on a residential street with 55% impervious surface were given the opportunity for free rain barrels, rain gardens, and bioretention cells. Of 163 parcels, only 22 owners (13.5%) chose to participate, despite intense outreach efforts. After pre-treatment monitoring, 37 rain barrels, 7 rain gardens, and 16 street-side bioretention cells were installed in 2013-2014. Using a paired watershed approach, a reduction in up to 33% of peak flow and 40% of total runoff volume per storm was measured in the storm sewer. Using the monitoring data, a calibrated and validated SWMM model was built to explore the long-term effectiveness of the green infrastructure against a wider range of hydrological conditions. Model results confirm the effectiveness of green infrastructure in reducing surface runoff and increasing infiltration and evaporation. Based on 20 years of historical precipitation data, the model shows that the green infrastructure is capable of reducing flows by >40% at the 1, 2, and 5 year return period, suggesting some resilience to projected increases in precipitation intensity in a changing climate. Further, in this project, more benefit is derived from the street-side bioretention cells than from the rain barrels and gardens that treat rooftop runoff. Substantial hydrological gains were achieved despite low homeowner participation. Surveys indicate that many residents viewed stormwater as the city's problem and had negative perceptions of green infrastructure, despite slightly pro-environment values generally. Overall, this study demonstrates green infrastructure's hydrological effectiveness but raises challenging questions about overcoming social barriers retrofits at the neighborhood scale.

Linking ice accretion and crown structure: towards a model of the effect of freezing rain on tree canopies.

PubMed

Nock, Charles A; Lecigne, Bastien; Taugourdeau, Olivier; Greene, David F; Dauzat, Jean; Delagrange, Sylvain; Messier, Christian

2016-06-01

Despite a longstanding interest in variation in tree species vulnerability to ice storm damage, quantitative analyses of the influence of crown structure on within-crown variation in ice accretion are rare. In particular, the effect of prior interception by higher branches on lower branch accumulation remains unstudied. The aim of this study was to test the hypothesis that intra-crown ice accretion can be predicted by a measure of the degree of sheltering by neighbouring branches. Freezing rain was artificially applied to Acer platanoides L., and in situ branch-ice thickness was measured directly and from LiDAR point clouds. Two models of freezing rain interception were developed: 'IceCube', which uses point clouds to relate ice accretion to a voxel-based index (sheltering factor; SF) of the sheltering effect of branch elements above a measurement point; and 'IceTree', a simulation model for in silico evaluation of the interception pattern of freezing rain in virtual tree crowns. Intra-crown radial ice accretion varied strongly, declining from the tips to the bases of branches and from the top to the base of the crown. SF for branches varied strongly within the crown, and differences among branches were consistent for a range of model parameters. Intra-crown variation in ice accretion on branches was related to SF (R(2) = 0·46), with in silico results from IceTree supporting empirical relationships from IceCube. Empirical results and simulations confirmed a key role for crown architecture in determining intra-crown patterns of ice accretion. As suspected, the concentration of freezing rain droplets is attenuated by passage through the upper crown, and thus higher branches accumulate more ice than lower branches. This is the first step in developing a model that can provide a quantitative basis for investigating intra-crown and inter-specific variation in freezing rain damage. © The Author 2016. Published by Oxford University Press on behalf of the Annals of Botany Company. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Polarimetric Radar Retrievals in Southeast Texas During Hurricane Harvey

NASA Astrophysics Data System (ADS)

Wolff, D. B.; Petersen, W. A.; Tokay, A.; Marks, D. A.; Pippitt, J. L.; Kirstetter, P. E.

2017-12-01

Hurricane Harvey hit the Texas Gulf Coast as a major hurricane on August 25, 2017 before exiting the state as a tropical storm on September 1, 2017. In its wake, it left a flood of historic proportions, with some areas measuring 60 inches of rain over a five-day period. Although the storm center stayed west of the immediate Houston area training bands of precipitation impacted the Houston area for five full days. The National Weather Service (NWS) WSR88D dual-polarimetric radar (KHGX), located southeast of Houston, maintained operations for the entirety of the event. The Harris County Flood Warning System (HCFWS) had 150 rain gauges deployed in its network and seven NWS Automated Surface Observing Systems (ASOS) rain gauges are also located in the area. In this study, we used the full radar data set to retrieve daily and event-total precipitation estimates within 120 km of the KHGX radar for the period August 25-29, 2017. These estimates were then compared to the HCFWS and ASOS gauges. Three different polarimetric hybrid rainfall retrievals were used: Ciffeli et al. 2011; Bringi et al. 2004; and, Chen et al. 2017. Each of these hybrid retrievals have demonstrated robust performance in the past. However, both daily and event-total comparisons from each of these retrievals compared to those of HCFWS and ASOS rain gauge networks resulted in significant underestimates by the radar retrievals. These radar underestimates are concerning. Sources of error and variance will be investigated to understand the source of radar-gauge disagreement. One current hypothesis is that due to the large number of small drops often found in hurricanes, the differential reflectivity and specific differential phase are relatively small so that the hybrid algorithms use only the reflectivity/rain rate procedure (so called Z-R relationships), and hence rarely invoke the ZDR or KDP procedures. Thus, an alternative Z-R relationship must be invoked to retrieve accurate rain rate estimates.

Application of lightning data to satellite-based rainfall estimation

NASA Technical Reports Server (NTRS)

Martin, David W.; Hinton, Barry B.; Auvine, Brian A.

1991-01-01

Information on lightning may improve rain estimates made from infrared images of a geostationary satellite. We address this proposition through a case from the Cooperative Huntsville Meteorological Experiment (COHMEX). During the afternoon and evening of 13 July 1986 waves of showers and thunderstorms developed over and near the lower Tennessee River Valley. For the shower and thunderstorm region within 200 km of the National Weather Service radar at Nashville, Tennessee, we measure cold-cloud area in a sequence of GOES infrared images covering all but the end of the shower and thunderstorm period. From observations of the NASA/Marshall direction-finding network in this small domain, we also count cloud-to-ground lightning flashes and, from scans of the Nashville radar, we calculate volume rain flux. Using a modified version of the Williams and Houze scheme, over an area within roughly 240 km of the radar (the large domain), we identify and track cold cloud systems. For these systems, over the large domain, we measure area and count flashes; over the small domain, we calculate volume rain flux. For a temperature threshold of 235K, peak cloud area over the small domain lags both peak rain flux and peak flash count by about four hours. At a threshold of 226K, the lag is about two hours. Flashes and flux are matched in phase. Over the large domain, nine storm systems occur. These range in size from 300 to 60,000 km(exp 2); in lifetime, from about 2 1/2 h to 6 h or more. Storm system area lags volume rain flux and flash count; nevertheless, it is linked with these variables. In essential respects the associations were the same when clouds were defined by a threshold of 226K. Tentatively, we conclude that flash counts complement infrared images in providing significant additional information on rain flux.

KSC-02pd0994

NASA Image and Video Library

2002-06-18

KENNEDY SPACE CENTER, FLA. -- Black storm clouds roll in over the Vehicle Assembly Building, bringing thunder and heavy rain. This type of weather convinced flight control managers to wave off the two scheduled landing attempts at KSC for Endeavour, returning from mission STS-111

NASA AIRS Instrument Captures Data on Monster Winter Storm Affecting 30 States

NASA Image and Video Library

2011-02-02

This visible image from NASA Aqua satellite Jan. 31 shows thickening clouds along a developing intense front in the plains and Midwestern states that will produce excessive snow, freezing rain, sleet, and wind in those areas.

A Space-Based Perspective of the 2017 Hurricane Season from the Global Precipitation Measurement (GPM) Mission

NASA Astrophysics Data System (ADS)

Skofronick Jackson, G.; Petersen, W. A.; Huffman, G. J.; Kirschbaum, D.; Wolff, D. B.; Tan, J.; Zavodsky, B.

2017-12-01

The Global Precipitation Measurement (GPM) mission collected unique, near real time 3-D satellite-based views of hurricanes in 2017 together with estimated precipitation accumulation using merged satellite data for scientific studies and societal applications. Central to GPM is the NASA-JAXA GPM Core Observatory (CO). The GPM-CO carries an advanced dual-frequency precipitation radar (DPR) and a well-calibrated, multi-frequency passive microwave radiometer that together serve as an on orbit reference for precipitation measurements made by the international GPM satellite constellation. GPM-CO overpasses of major Hurricanes such as Harvey, Irma, Maria, and Ophelia revealed intense convective structures in DPR radar reflectivity together with deep ice-phase microphysics in both the eyewalls and outer rain bands. Of considerable scientific interest, and yet to be determined, will be DPR-diagnosed characteristics of the rain drop size distribution as a function of convective structure, intensity and microphysics. The GPM-CO active/passive suite also provided important decision support information. For example, the National Hurricane Center used GPM-CO observations as a tool to inform track and intensity estimates in their forecast briefings. Near-real-time rainfall accumulation from the Integrated Multi-satellitE Retrievals for GPM (IMERG) was also provided via the NASA SPoRT team to Puerto Rico following Hurricane Maria when ground-based radar systems on the island failed. Comparisons between IMERG, NOAA Multi-Radar Multi-Sensor data, and rain gauge rainfall accumulations near Houston, Texas during Hurricane Harvey revealed spatial biases between ground and IMERG satellite estimates, and a general underestimation of IMERG rain accumulations associated with infrared observations, collectively illustrating the difficulty of measuring rainfall in hurricanes.GPM data continue to advance scientific research on tropical cyclone intensification and structure, and contribute to societal and operational applications for improving storm forecasting. Precipitation accumulations from the multi-satellite product IMERG also contribute to a better understanding of rainfall accumulation, inland flooding, and landslide susceptibility during the passage of these major events.

Measurements of rain effects on an 18-GHz dual-polarized propagation link

NASA Technical Reports Server (NTRS)

Bostian, C. W.; Stutzman, W. L.; Wiley, P. H.; Marshall, R. E.

1976-01-01

The paper presents highlights of rain attenuation and depolarization data collected between August 1972 and March 1974 in an experimental setup consisting of a 1.43-km line-of-sight path with 1.22-m diam dual-polarized parabolic reflector antennas at each end. The antennas used question-mark mounted scalar feeds oriented to transmit or receive linearly polarized 17.65-GHz signals having electric field vectors at +45 deg and -45 deg from the vertical. Rain data were collected and analyzed for 24 individual storms in which the rain rate exceeded 10 mm/hr. Received signal levels were sampled once each second and stored by a small digital computer which controlled the experiment and performed preliminary data processing. The results are compared with a theoretical model presented by Wiley et al. (1974). Experimental cross-polarization isolation data are found to agree well with theoretical values, especially at high rain rates where the antenna effects are the least significant.

Acid-rain induced changes in streamwater quality during storms on Catoctin Mountain, Maryland

USGS Publications Warehouse

Rice, Karen C.; Bricker, O.P.

1992-01-01

Catoctin Mountain receives some of the most acidic (lowest pH) rain in the United States. In 1990, the U.S. Geological Survey (USGS), in cooperation with the Maryland Department of the Environment (MDE) and the Maryland Department of Natural Resources (DNR), began a study of the effects of acid rain on the quality of streamwater on the part of Catoctin Mountain within Cunningham Falls State Park, Maryland (fig. 1). Samples of precipitation collected on the mountain by the USGS since 1982 have been analyzed for acidity and concentration of chemical constituents. During 1982-91, the volume-weighted average pH of precipitation was 4.2. (Volume weighting corrects for the effect of acids being washed out of the atmosphere at the beginning of rainfall). The pH value is measured on a logarithmic scale, which means that for each whole number change, the acidity changes by a factor of 10. Thus rain with a pH of 4.2 is more than 10 times as acidic as uncontaminated rain, which has a pH of about 5.6. The acidity of rain during several rainstorms on Catoctin Mountain was more than 100 times more acidic than uncontaminated rain.

The weight of a storm: what observations of Earth surface deformation can tell us about Hurricane Harvey

NASA Astrophysics Data System (ADS)

Borsa, A. A.; Mencin, D.; van Dam, T. M.

2017-12-01

Hurricane Harvey was the first major hurricane to impact the USA in over a decade, making landfall southwest of Houston, TX on August 26, 2017. Although Harvey was downgraded to a tropical storm shortly after landfall, it dropped a record amount of rain and was responsible for epic flooding across much of southeast Texas. While precipitation from a large storm like Harvey can be estimated from in-situ rain gages and Doppler radar, the accompanying surface water changes that lead to flooding are imperfectly observed due to the limited coverage of existing stream and lake level gages and because floodwaters inundate areas that are typically unmonitored. Earth's response to changes in surface loading provides an opportunity to observe the local hydrological response to Hurricane Harvey, specifically the dramatic changes in water storage coincident with and following the storm. Continuous GPS stations in southeastern Texas observed an average drop in land surface elevations of 1.8 cm following Harvey's landfall, followed by a gradual recovery to pre-storm levels over the following month. We interpret this surface motion as Earth's elastic response to the weight of cumulative rainfall during the storm, followed by rebound as that weight was removed by runoff and evapotranspiration (ET). Using observations of surface displacements from GPS stations in the HoustonNET and Plate Boundary Observatory networks, we model the daily water storage changes across Texas and Louisiana associated with Harvey. Because Harvey's barometric pressure low caused surface uplift at the cm level which temporarily obscured the subsidence signal due to precipitation, we model and remove the effect of atmospheric loading from the GPS data prior to our analysis. We also consider the effect on GPS position time series of non-tidal ocean loading due to the hurricane storm surge, which at the coast was an order of magnitude larger than loads due to precipitation alone. Finally, we use our results to estimate 1) the total precipitation load from the storm, 2) the spatial distribution of flooding, and 3) the runoff/ET component of water storage changes (incorporating independent estimates of precipitation).

Snoozing through the storm: torpor use during a natural disaster

PubMed Central

Nowack, Julia; Rojas, A. Daniella; Körtner, Gerhard; Geiser, Fritz

2015-01-01

Although storms provide an extreme environmental challenge to organisms and are predicted to increase in frequency and intensity due to climate change, there are no quantitative observations on the behaviour and physiology of animals during natural disasters. We provide the first data on activity and thermal biology of a free-ranging, arboreal mammal during a storm with heavy rain and category 1 cyclone wind speeds. We studied a population of sugar gliders (Petaurus breviceps), a species vulnerable to bad weather due to their small body size and mode of locomotion, in a subtropical habitat during spring when storms are common. Although torpor is generally rare in this species, sugar gliders remained inactive or reduced foraging times during the storm and further minimized energy demands by entering deep torpor. All animals survived the storm and reverted to normal foraging activity during the following night(s). It thus appears that heterothermic mammals have a crucial adaptive advantage over homeothermic species as they can outlast challenging weather events, such as storms and floods, by reducing metabolism and thus energetic needs. PMID:26073747

Snoozing through the storm: torpor use during a natural disaster.

PubMed

Nowack, Julia; Rojas, A Daniella; Körtner, Gerhard; Geiser, Fritz

2015-06-15

Although storms provide an extreme environmental challenge to organisms and are predicted to increase in frequency and intensity due to climate change, there are no quantitative observations on the behaviour and physiology of animals during natural disasters. We provide the first data on activity and thermal biology of a free-ranging, arboreal mammal during a storm with heavy rain and category 1 cyclone wind speeds. We studied a population of sugar gliders (Petaurus breviceps), a species vulnerable to bad weather due to their small body size and mode of locomotion, in a subtropical habitat during spring when storms are common. Although torpor is generally rare in this species, sugar gliders remained inactive or reduced foraging times during the storm and further minimized energy demands by entering deep torpor. All animals survived the storm and reverted to normal foraging activity during the following night(s). It thus appears that heterothermic mammals have a crucial adaptive advantage over homeothermic species as they can outlast challenging weather events, such as storms and floods, by reducing metabolism and thus energetic needs.

Origin of storm footprints on the sea seen by synthetic aperture radar.

PubMed

Atlas, D

1994-11-25

Spaceborne synthetic aperture radar can detect storm footprints on the sea. Coastal weather radar from Cape Hatteras provides evidence that the echo-free hole at the footprint core is the result of wave damping by rain. The increased radar cross section of the sea surrounding the echo-free hole results from the divergence of the precipitation-forced downdraft impacting the sea. The footprint boundary is the gust front; its oriention is aligned with the direction of the winds aloft, which are transported down with the downdraft, and its length implies downdraft impact 1 hour earlier at a quasi-stationary impact spot. The steady, localized nature of the storm remains a mystery.

TRMM Precipitation Radar Reflectivity Profiles Compared to High-Resolution Airborne and Ground-Based Radar Measurements

NASA Technical Reports Server (NTRS)

Heymsfield, G. M.; Geerts, B.; Tian, L.

1999-01-01

In this paper, TRMM (Tropical Rainfall Measuring Mission Satellite) Precipitation Radar (PR) products are evaluated by means of simultaneous comparisons with data from the high-altitude ER-2 Doppler Radar (EDOP), as well as ground-based radars. The comparison is aimed primarily at the vertical reflectivity structure, which is of key importance in TRMM rain type classification and latent heating estimation. The radars used in this study have considerably different viewing geometries and resolutions, demanding non-trivial mapping procedures in common earth-relative coordinates. Mapped vertical cross sections and mean profiles of reflectivity from the PR, EDOP, and ground-based radars are compared for six cases. These cases cover a stratiform frontal rainband, convective cells of various sizes and stages, and a hurricane. For precipitating systems that are large relative to the PR footprint size, PR reflectivity profiles compare very well to high-resolution measurements thresholded to the PR minimum reflectivity, and derived variables such as bright band height and rain types are accurate, even at high PR incidence angles. It was found that for, the PR reflectivity of convective cells small relative to the PR footprint is weaker than in reality. Some of these differences can be explained by non-uniform beam filling. For other cases where strong reflectivity gradients occur within a PR footprint, the reflectivity distribution is spread out due to filtering by the PR antenna illumination pattern. In these cases, rain type classification may err and be biased towards the stratiform type, and the average reflectivity tends to be underestimated. The limited sensitivity of the PR implies that the upper regions of precipitation systems remain undetected and that the PR storm top height estimate is unreliable, usually underestimating the actual storm top height. This applies to all cases but the discrepancy is larger for smaller cells where limited sensitivity is compounded by incomplete beam filling. Users of level three TRMM PR products should be aware of this scale dependency.

Improved Performance Analysis of Free Space Optics Communication Link under Rain Conditions using EDFA Pre-amplifier

NASA Astrophysics Data System (ADS)

Singh, Mehtab

2018-04-01

Free Space Optics (FSO) also known as Optical Wireless Communication (OWC) is a communication technology in which free space/air is used as the propagation medium and optical signals are used as the information carriers. One of the most crucial factors which degrade the performance of FSO link is the signal attenuation due to different atmospheric weather conditions such as haze, rain, storm, and fog. In this paper, an improved performance analysis of a 2.5 Gbps FSO link under rain conditions has been reported using Erbium-Doped Fiber Amplifier (EDFA) as a pre-amplifier. The results show that the maximum link distance for an FSO link under rain weather conditions with acceptable performance levels (Q ˜6 and BER ≤ 10-9 in the absence of EDFA pre-amplifier is 1,250 m which increases to 1,675 m with the use of EDFA pre-amplifier.

On the utilization of hydrological modelling for road drainage design under climate and land use change.

PubMed

Kalantari, Zahra; Briel, Annemarie; Lyon, Steve W; Olofsson, Bo; Folkeson, Lennart

2014-03-15

Road drainage structures are often designed using methods that do not consider process-based representations of a landscape's hydrological response. This may create inadequately sized structures as coupled land cover and climate changes can lead to an amplified hydrological response. This study aims to quantify potential increases of runoff in response to future extreme rain events in a 61 km(2) catchment (40% forested) in southwest Sweden using a physically-based hydrological modelling approach. We simulate peak discharge and water level (stage) at two types of pipe bridges and one culvert, both of which are commonly used at Swedish road/stream intersections, under combined forest clear-cutting and future climate scenarios for 2050 and 2100. The frequency of changes in peak flow and water level varies with time (seasonality) and storm size. These changes indicate that the magnitude of peak flow and the runoff response are highly correlated to season rather than storm size. In all scenarios considered, the dimensions of the current culvert are insufficient to handle the increase in water level estimated using a physically-based modelling approach. It also appears that the water level at the pipe bridges changes differently depending on the size and timing of the storm events. The findings of the present study and the approach put forward should be considered when planning investigations on and maintenance for areas at risk of high water flows. In addition, the research highlights the utility of physically-based hydrological models to identify the appropriateness of road drainage structure dimensioning. Copyright © 2014 Elsevier B.V. All rights reserved.

Heavy thunderstorms observed over land by the Nimbus 7 scanning multichannel microwave radiometer

NASA Technical Reports Server (NTRS)

Spencer, R. W.; Olson, W. S.; Martin, D. W.; Weinman, J. A.; Santek, D. A.; Wu, R.

1983-01-01

Brightness temperatures obtained through examination of microwave data from the Nimbus 7 satellite are noted to be much lower than those expected on the strength of radiation emanating from rain-producing clouds. Very cold brightness temperature cases all coincided with heavy thunderstorm rainfall, with the cold temperatures being attributable to scattering by a layer of ice hydrometeors in the upper parts of the storms. It is accordingly suggested that brightness temperatures observed by satellite microwave radiometers can sometimes distinguish heavy rain over land.

Have Tropical Cyclones Been Feeding More Extreme Rainfall?

NASA Technical Reports Server (NTRS)

Lau, K.-M.; Zhou, Y. P.; Wu, H.-T.

2008-01-01

We have conducted a study of the relationship between tropical cyclone (TC) and extreme rain events using GPCP and TRMM rainfall data, and storm track data for July through November (JASON) in the North Atlantic (NAT) and the western North Pacific (WNP). Extreme rain events are defined in terms of percentile rainrate, and TC-rain by rainfall associated with a named TC. Results show that climatologically, 8% of rain events and 17% of the total rain amount in NAT are accounted by TCs, compared to 9% of rain events and 21% of rain amount in WNP. The fractional contribution of accumulated TC-rain to total rain, Omega, increases nearly linearly as a function of rainrate. Extending the analyses using GPCP pentad data for 1979-2005, and for the post-SSM/I period (1988-2005), we find that while there is no significant trend in the total JASON rainfall over NAT or WNP, there is a positive significant trend in heavy rain over both basins for the 1979-2005 period, but not for the post-SSM/I period. Trend analyses of Omega for both periods indicate that TCs have been feeding increasingly more to rainfall extremes in NAT, where the expansion of the warm pool area can explain slight more than 50% of the change in observed trend in total TC rainfall. In WNP, trend signals for Omega are mixed, and the long-term relationship between TC rain and warm pool areas are strongly influenced by interannual and interdecadal variability.

Estimating soil moisture exceedance probability from antecedent rainfall

NASA Astrophysics Data System (ADS)

Cronkite-Ratcliff, C.; Kalansky, J.; Stock, J. D.; Collins, B. D.

2016-12-01

The first storms of the rainy season in coastal California, USA, add moisture to soils but rarely trigger landslides. Previous workers proposed that antecedent rainfall, the cumulative seasonal rain from October 1 onwards, had to exceed specific amounts in order to trigger landsliding. Recent monitoring of soil moisture upslope of historic landslides in the San Francisco Bay Area shows that storms can cause positive pressure heads once soil moisture values exceed a threshold of volumetric water content (VWC). We propose that antecedent rainfall could be used to estimate the probability that VWC exceeds this threshold. A major challenge to estimating the probability of exceedance is that rain gauge records are frequently incomplete. We developed a stochastic model to impute (infill) missing hourly precipitation data. This model uses nearest neighbor-based conditional resampling of the gauge record using data from nearby rain gauges. Using co-located VWC measurements, imputed data can be used to estimate the probability that VWC exceeds a specific threshold for a given antecedent rainfall. The stochastic imputation model can also provide an estimate of uncertainty in the exceedance probability curve. Here we demonstrate the method using soil moisture and precipitation data from several sites located throughout Northern California. Results show a significant variability between sites in the sensitivity of VWC exceedance probability to antecedent rainfall.

Initiation of Recent Debris Flows on Mount Rainier, Washington: A Climate Warming Signal?

NASA Astrophysics Data System (ADS)

Copeland, E. A.; Kennard, P.; Nolin, A. W.; Lancaster, S. T.; Grant, G. E.

2008-12-01

The first week of November 2006 an intense rainstorm inundated the Pacific Northwest and triggered debris flows on many large volcanoes in the Cascade Range of Washington and Oregon. At Mount Rainier, Washington, 45.7 cm of rain was recorded in 36 hours; the storm was preceded by a week of light precipitation and moderate temperatures, so that rain fell on nearly-saturated ground with minimal snow cover. The November 2006 storm was exceptional in that it resulted in a 100-year flood and caused an unprecedented six-month closure of Mount Rainier National Park. It also focused inquiry as to whether debris flows from Cascade volcanoes are likely to occur more frequently in the future as glaciers recede due to climate warming, leaving unstable moraines and sediment that can act as initiation sites. We examined the recent history of debris flows from Mount Rainier using aerial photographs and field surveyed debris flow tracks. Prior to 2001, debris flows were recorded in association with rainfall or glacial outburst floods in 4 drainages, but 3 additional drainages were first impacted by debris flows in 2001, 2005, and 2006, respectively. We discovered that most of the recent debris flows initiated as small gullies in unconsolidated material at the edge of fragmented glaciers or areas of permanent snow and ice. Other initiation sites occur on steep-sided un-vegetated moraines. Of the 28 named glaciers on Mount Rainier, debris flows initiated near five glaciers in the exceptional storm of 2006 (Winthrop, Inter, Kautz-Success, Van Trump, Pyramid, and South Tahoma). Less exceptional storms, however, have also produced wide-spread debris flows: in September 2005, 15.3 cm of rain fell in 48 hours on minimal snow cover and caused debris flows in all except 2 of the glacier drainages that initiated in 2006. Debris flows from both storms initiated at elevations of 1980 to 2400 m, traveled 5 to 10 kilometers, and caused significant streambed aggradation. These results suggest a complex view of debris flow initiation. Retreat and fragmentation of glaciers create debris-covered stagnant ice masses in the steep-sided, tiered channels and expose steep edifices of unstable glacial material, both of which may promote debris flow initiation. Possible reduced snow cover and higher freezing levels during autumn storms due to climate warming may further influence debris flow initiation on the glaciated stratovolcanoes of Washington and Oregon.

Quantitative and qualitative hydrologic balance for a suburban watershed with a separate sewer system (Nantes, France).

PubMed

Ruban, V; Larrarte, F; Berthier, M; Favreau, L; Sauvourel, Y; Letellier, L; Mosisni, M L; Raimbault, G

2005-01-01

A qualitative and quantitative budget at the outlet of the storm-water runoff system of a small suburban watershed is presented together with some data regarding waste-water. 445,000 m3 (34% of the rain-water volume) were drained by the storm-water runoff system and 40,879 m3 by the waste-water system from September 2002 to March 2004. Storm-water runoff is generally not heavily polluted with regard to trace metals but concentrations occasionally exceed the standards for surface water of good quality. On the contrary, pesticides (diuron and glyphosate) have very high concentrations especially in spring and autumn when their use is maximum. As the St Joseph storm-water runoff is finally discharged into the Erdre River, measures to reduce the use of these pollutants should be considered.

The Impact of Drainage Network Structure on Flooding in a Small Urban Watershed in Metropolitan Baltimore, MD

NASA Astrophysics Data System (ADS)

Meierdiercks, K. L.; Smith, J. A.; Miller, A. J.

2006-12-01

The impact of urban development on watershed-scale hydrology is examined in a small urban watershed in the Metropolitan Baltimore area. Analyses focus on Dead Run, a 14.3 km2 tributary of the Gwynns Falls, which is the principal study watershed of the Baltimore Ecosystem Study. Field observations of rainfall and discharge have been collected for storms occurring in the 2003, 2004, and 2005 warm seasons including the flood of record for the USGS Dead Run at Franklintown gage (7 July 2004), in which 5 inches of rain fell in less than 4 hours. Dead Run has stream gages at 6 locations with drainage areas ranging from 1.2 to 14.3 km2. Hydrologic response to storm events varies greatly in each of the subwatersheds due to the diverse development types located there. These subwatersheds range in land use from medium-density residential, with and without stormwater management control, to commercial/light industrial with large impervious lots and an extensive network of stormwater management ponds. The unique response of each subwatershed is captured using field observations in conjunction with the EPA Stormwater Management Model (SWMM), which routes storm runoff over the land surface and through the drainage network of a watershed. Of particular importance to flood response is the structure of the drainage network (both surface channels and storm drain network) and its connectivity to preferential flow paths within the watershed. The Dead Run drainage network has been delineated using geospatial data derived from aerial photography and engineering planning drawings. Model analyses are used to examine the characteristics of flow paths that control flood response in urban watersheds. These analyses aim to identify patterns in urban flow pathways and use those patterns to predict response in other urban watersheds.

Assimilation of GPM GMI Rainfall Product with WRF GSI

NASA Technical Reports Server (NTRS)

Li, Xuanli; Mecikalski, John; Zavodsky, Bradley

2015-01-01

The Global Precipitation Measurement (GPM) is an international mission to provide next-generation observations of rain and snow worldwide. The GPM built on Tropical Rainfall Measuring Mission (TRMM) legacy, while the core observatory will extend the observations to higher latitudes. The GPM observations can help advance our understanding of precipitation microphysics and storm structures. Launched on February 27th, 2014, the GPM core observatory is carrying advanced instruments that can be used to quantify when, where, and how much it rains or snows around the world. Therefore, the use of GPM data in numerical modeling work is a new area and will have a broad impact in both research and operational communities. The goal of this research is to examine the methodology of assimilation of the GPM retrieved products. The data assimilation system used in this study is the community Gridpoint Statistical Interpolation (GSI) system for the Weather Research and Forecasting (WRF) model developed by the Development Testbed Center (DTC). The community GSI system runs in independently environment, yet works functionally equivalent to operational centers. With collaboration with the NASA Short-term Prediction Research and Transition (SPoRT) Center, this research explores regional assimilation of the GPM products with case studies. Our presentation will highlight our recent effort on the assimilation of the GPM product 2AGPROFGMI, the retrieved Microwave Imager (GMI) rainfall rate data for initializing a real convective storm. WRF model simulations and storm scale data assimilation experiments will be examined, emphasizing both model initialization and short-term forecast of precipitation fields and processes. In addition, discussion will be provided on the development of enhanced assimilation procedures in the GSI system with respect to other GPM products. Further details of the methodology of data assimilation, preliminary result and test on the impact of GPM data and the influence on precipitation forecast will be presented at the conference.

Analyzing post-wildfire erosional processes and topographic change using hydrologic monitoring and Structure-from-Motion photogrammetry at the storm event scale

NASA Astrophysics Data System (ADS)

Leeper, R. J.; Barth, N. C.; Gray, A. B.

2017-12-01

Hydro-geomorphic response in recently burned watersheds is highly dependent on the timing and magnitude of subsequent rainstorms. Recent advancements in surveying and monitoring techniques using Unmanned Aerial Vehicles (UAV) and Structure-from-Motion (SfM) photogrammetry can support the rapid estimation of near cm-scale topographic response of headwater catchments (ha to km2). However, surface change due to shallow erosional processes such as sheetwash and rilling remain challenging to measure at this spatial extent and the storm event scale. To address this issue, we combined repeat UAV-SfM surveys with hydrologic monitoring techniques and field investigations to characterize post-wildfire erosional processes and topographic change on a storm-by-storm basis. The Las Lomas watershed ( 15 ha) burned in the 2016 San Gabriel Complex Fire along the front range of the San Gabriel Mountains, southern California. Surveys were conducted with a consumer grade UAV; twenty-six SfM control markers; two rain gages, and two pressure transducers were installed in the watershed. The initial SfM-derived point cloud generated from 422 photos contains 258 million points; the DEM has a resolution of 2.42 cm/pixel and a point density of 17.1 pts/cm2. Rills began forming on hillslopes and minor erosion occurred within the channel network during the first low intensity storms of the rainy season. Later more intense storms resulted in substantial geomorphic change. Hydrologic data indicate that during one of the intense storms total cumulative rainfall was 58.20 mm and peak 5-min intensity was 38.4 mm/hr. Poststorm field surveys revealed evidence of debris flows, flash flooding, erosion, and fluvial aggradation in the channel network, and rill growth and gully formation on hillslopes. Analyses of the SfM models indicate erosion dominated topographic change in steep channels and on hillslopes; aggradation dominated change in low gradient channels. A contrast of 5 cm exists between field measurements and change detected by differencing the SfM models. The quantitative and qualitative data sets obtained indicate that low-cost hydrologic monitoring techniques can be combined with SfM-derived high-resolution models to rapidly characterize post-wildfire hydrologic response and erosional processes on a storm event basis.

Storm rainfall conditions for floods and debris flows from recently burned areas in southwestern Colorado and southern California

USGS Publications Warehouse

Cannon, S.H.; Gartner, J.E.; Wilson, R.C.; Bowers, J.C.; Laber, J.L.

2008-01-01

Debris flows generated during rain storms on recently burned areas have destroyed lives and property throughout the Western U.S. Field evidence indicate that unlike landslide-triggered debris flows, these events have no identifiable initiation source and can occur with little or no antecedent moisture. Using rain gage and response data from five fires in Colorado and southern California, we document the rainfall conditions that have triggered post-fire debris flows and develop empirical rainfall intensity-duration thresholds for the occurrence of debris flows and floods following wildfires in these settings. This information can provide guidance for warning systems and planning for emergency response in similar settings. Debris flows were produced from 25 recently burned basins in Colorado in response to 13 short-duration, high-intensity convective storms. Debris flows were triggered after as little as six to 10??min of storm rainfall. About 80% of the storms that generated debris flows lasted less than 3??h, with most of the rain falling in less than 1??h. The storms triggering debris flows ranged in average intensity between 1.0 and 32.0??mm/h, and had recurrence intervals of two years or less. Threshold rainfall conditions for floods and debris flows sufficiently large to pose threats to life and property from recently burned areas in south-central, and southwestern, Colorado are defined by: I = 6.5D-??0.7 and I = 9.5D-??0.7, respectively, where I = rainfall intensity (in mm/h) and D = duration (in hours). Debris flows were generated from 68 recently burned areas in southern California in response to long-duration frontal storms. The flows occurred after as little as two hours, and up to 16??h, of low-intensity (2-10??mm/h) rainfall. The storms lasted between 5.5 and 33??h, with average intensities between 1.3 and 20.4??mm/h, and had recurrence intervals of two years or less. Threshold rainfall conditions for life- and property-threatening floods and debris flows during the first winter season following fires in Ventura County, and in the San Bernardino, San Gabriel and San Jacinto Mountains of southern California are defined by I = 12.5D-0.4, and I = 7.2D-0.4, respectively. A threshold defined for flood and debris-flow conditions following a year of vegetative recovery and sediment removal for the San Bernardino, San Gabriel and San Jacinto Mountains of I = 14.0D-0.5 is approximately 25??mm/h higher than that developed for the first year following fires. The thresholds defined here are significantly lower than most identified for unburned settings, perhaps because of the difference between extremely rapid, runoff-dominated processes acting in burned areas and longer-term, infiltration-dominated processes on unburned hillslopes. Crown Copyright ?? 2007.

Map of debris flows caused by rainfall during 1996 in parts of the Reedsport and Deer Head Point quadrangles, Douglas County, southern Coast Range, Oregon

USGS Publications Warehouse

Coe, Jeffrey A.; Michael, John A.; Burgos, Marianela Mercado

2011-01-01

This 1:12,000-scale map shows an inventory of debris flows caused by rainfall during 1996 in a 94.4 km2 area in the southern Coast Range of Oregon. This map and associated digital data are part of a larger U.S. Geological Survey study of debris flows in the southern Coast Range. Available evidence indicates that the flows were triggered by a rain storm that occurred between November 17 and 19. The closest rain gage in the Coast Range (Goodwin Peak) recorded 245 mm during the storm. Maximum rainfall intensity during the storm was 13.2 mm/hr on November 18. Debris flows were photogrammetrically mapped from 1:12,000-scale aerial photographs flown in May, 1997. The inventory is presented on imagery derived from LiDAR data acquired in 2008. We classified mapped debris flows into four categories based on the type of debris-flow activity: (1) discrete slide source areas, (2) predominantly erosion, (3) predominantly transport or mixed erosion and deposition, and (4) predominantly deposition. Locations of woody-debris jams are also shown on the map. The area encompassed by debris flows is 2.1 percent of the 94.4 km2 map area.

NASA Sees Storms Affecting the Western U.S.

NASA Image and Video Library

2017-12-08

Extreme rain events have been affecting California and snow has blanketed the Pacific Northwest. This visible image from NASA's Aqua satellite on Jan. 6, 2017, at 3:35 p.m. EST (20:35 UTC) shows snow cover in the U.S. Pacific Northwest in Washington, Idaho, Oregon, northern California and Nevada. On Jan. 9, another area of low pressure moved over Oregon, where the National Weather Service is forecasting heavy snows. It was the same week last year that the West Coast endured a similar bout of very wet weather. Heavy rain affected the Pacific coast in 2016 during the same week from Jan. 5 through Jan. 7, as a progression of storm systems in the Eastern Pacific Ocean hit southern California and generated flooding and mudslides. For updated forecasts, visit the National Weather Service website at: www.weather.gov Learn more about NASA's view of the storm: go.nasa.gov/2j0xpvW Credits: NASA Goddard MODIS Rapid Response NASA image use policy. NASA Goddard Space Flight Center enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission. Follow us on Twitter Like us on Facebook Find us on Instagram

Winter storm intensity, hazards, and property losses in the New York tristate area.

PubMed

Shimkus, Cari E; Ting, Mingfang; Booth, James F; Adamo, Susana B; Madajewicz, Malgosia; Kushnir, Yochanan; Rieder, Harald E

2017-07-01

Winter storms pose numerous hazards to the Northeast United States, including rain, snow, strong wind, and flooding. These hazards can cause millions of dollars in damages from one storm alone. This study investigates meteorological intensity and impacts of winter storms from 2001 to 2014 on coastal counties in Connecticut, New Jersey, and New York and underscores the consequences of winter storms. The study selected 70 winter storms on the basis of station observations of surface wind strength, heavy precipitation, high storm tide, and snow extremes. Storm rankings differed between measures, suggesting that intensity is not easily defined with a single metric. Several storms fell into two or more categories (multiple-category storms). Following storm selection, property damages were examined to determine which types lead to high losses. The analysis of hazards (or events) and associated damages using the Storm Events Database of the National Centers for Environmental Information indicates that multiple-category storms were responsible for a greater portion of the damage. Flooding was responsible for the highest losses, but no discernible connection exists between the number of storms that afflict a county and the damage it faces. These results imply that losses may rely more on the incidence of specific hazards, infrastructure types, and property values, which vary throughout the region. © 2017 The Authors. Annals of the New York Academy of Sciences published by Wiley Periodicals Inc. on behalf of The New York Academy of Sciences.

Supertyphoon Pongsona

NASA Technical Reports Server (NTRS)

2002-01-01

[figure removed for brevity, see original site] [figure removed for brevity, see original site] Vis/NIR image close-upAIRS infrared window channelHSB microwave channel Three Different Views of Supertyphoon Pongsona, December 2002

Packing gusts of 296.1 kilometers per hour (184 miles per hour) and sustained winds of 241.4 kilometers per hour (150 miles per hour), Supertyphoon Pongsona struck the U.S. Island of Guam on Sunday, December 8. The storm cut off electricity over the entire island along with telephone and water service, and President George W. Bush declared the U.S. territory a federal disaster area. Pongsona is the third typhoon to hit Guam since June, and the second cyclone of supertyphoon status to hit in five years.

These images were made from data acquired by the Atmospheric Infrared Sounding System (AIRS) instrument suite aboard NASA's Aqua spacecraft just as the eye of the storm was about to pass over Guam.

This image was made using visible/near-infrared data using the AIRS instrument. Its 2-kilometer (1.24-mile) resolution shows fine details of the cloud structure and can be used to help interpret the other images. It confirms that the eye was not cloud free at the time the data was acquired, and pinpoints towering thunderheads rising up in several areas of the spiral arms (see figure 1 for close-up).

The image in figure 2 shows how the typhoon looks through an AIRS infrared 'window' channel, which measures the temperature of the nearest impenetrable surface. Where the sky is clear, this window channel shows the surface of the Earth, otherwise it will show cloud tops. High cold clouds appear blue, while lower warmer clouds are green through orange. The Earth's surface, where it can be seen between the clouds, is warmest and appears red. Although the storm has a clearly defined eye, it is not cloud free and therefore shows up as yellow in this infrared image.

The image in figure 3 shows how the typhoon looks through a microwave channel of the Humidity Sounder for Brazil (HSB), a component of the AIRS instrument suite. This channel, which is sensitive to humidity, clouds and rain, sees through much of the clouds and reveals some of the inner structure of the storm. Here the eye is more clearly defined than in the infrared image and appears to be very large - perhaps 80.5 kilometers (50 miles) across. Rain areas appear as blue patches, and a very intense rain cell can be seen right over Guam itself. This cell is in the leading eye wall and is probably associated with the highest wind speeds. It is likely that much of the damage in Guam was caused by this particular part of the storm.

In the near future, when estimates of the three-dimensional distribution of the temperature, humidity and clouds in the atmosphere are also routinely derived from the AIRS sounding system, it will be possible to get a unique view of the interior of destructive storms like Pongsona. The new knowledge gained will eventually make for more accurate forecasts of such events.

The Atmospheric Infrared Sounder Experiment, with its visible, infrared, and microwave detectors, provides a three-dimensional look at Earth's weather. Working in tandem, the three instruments can make simultaneous observations all the way down to the Earth's surface, even in the presence of heavy clouds. With more than 2,000 channels sensing different regions of the atmosphere, the system creates a global, 3-D map of atmospheric temperature and humidity and provides information on clouds, greenhouse gases, and many other atmospheric phenomena. The AIRS Infrared Sounder Experiment flies onboard NASA's Aqua spacecraft and is managed by NASA's Jet Propulsion Laboratory, Pasadena, Calif., under contract to NASA. JPL is a division of the California Institute of Technology in Pasadena

Satellite Video Shows Movement of Major U.S. Winter Storm

NASA Image and Video Library

2014-02-12

View a video of the storm here: bit.ly/1m9aJFY This visible image of the winter storm over the U.S. south and East Coast was taken by NOAA's GOES-13 satellite on Feb. 12 at 1855 UTC/1:55 p.m. EST. Snow covered ground can be seen over the Great Lakes region and Ohio Valley. On February 12 at 10 a.m. EST, NOAA's National Weather Service or NWS continued to issue watches and warnings from Texas to New England. Specifically, NWS cited Winter Storm Warnings and Winter Weather Advisories were in effect from eastern Texas eastward across the interior section of southeastern U.S. states and across much of the eastern seaboard including the Appalachians. Winter storm watches are in effect for portions of northern New England as well as along the western slopes of northern and central Appalachians. For updates on local forecasts, watches and warnings, visit NOAA's www.weather.gov webpage. NOAA's Weather Prediction Center or WPC noted the storm is expected to bring "freezing rain spreading into the Carolinas, significant snow accumulations are expected in the interior Mid-Atlantic states tonight into Thursday and ice storm warnings and freezing rain advisories are in effect across much of central Georgia. GOES satellites provide the kind of continuous monitoring necessary for intensive data analysis. Geostationary describes an orbit in which a satellite is always in the same position with respect to the rotating Earth. This allows GOES to hover continuously over one position on Earth's surface, appearing stationary. As a result, GOES provide a constant vigil for the atmospheric "triggers" for severe weather conditions such as tornadoes, flash floods, hail storms and hurricanes. For updated information about the storm system, visit NOAA's WPC website; www.hpc.ncep.noaa.gov/ For more information about GOES satellites, visit: www.goes.noaa.gov/ or goes.gsfc.nasa.gov/ Rob Gutro NASA's Goddard Space Flight Center Credit: NOAA/NASA GOES Project NASA image use policy. NASA Goddard Space Flight Center enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission. Follow us on Twitter Like us on Facebook Find us on Instagram

KSC-2011-2646

NASA Image and Video Library

2011-03-31

CAPE CANAVERAL, Fla. – An osprey wades in flooded grass near the Vehicle Assembly Building at NASA's Kennedy Space Center in Florida. Severe storms associated with a frontal system are moving through Central Florida, producing strong winds, heavy rain, frequent lightning and even funnel clouds. Photo credit: NASA/Ben Smegelsky

KSC-2011-2649

NASA Image and Video Library

2011-03-31

CAPE CANAVERAL, Fla. – An osprey wades in flooded grass near the Vehicle Assembly Building at NASA's Kennedy Space Center in Florida. Severe storms associated with a frontal system are moving through Central Florida, producing strong winds, heavy rain, frequent lightning and even funnel clouds. Photo credit: NASA/Ben Smegelsky

KSC-2011-2647

NASA Image and Video Library

2011-03-31

CAPE CANAVERAL, Fla. – An osprey wades in flooded grass near the Vehicle Assembly Building at NASA's Kennedy Space Center in Florida. Severe storms associated with a frontal system are moving through Central Florida, producing strong winds, heavy rain, frequent lightning and even funnel clouds. Photo credit: NASA/Ben Smegelsky

Vacuum Spheres Outside of Building 1247 NASA LaRC

NASA Image and Video Library

2013-06-07

The vacuum spheres outside of building 1247 are reflected in a pool of rain water after an unusual break in weather on Friday, which gave a brief moment of sunshine, blue skies and standing water as Tropical Storm Andrea approaches from the south.

Investigation of Mercury Wet Deposition Physicochemistry in the Ohio River Valley through Automated Sequential Sampling

EPA Science Inventory

Intra-storm variability and soluble fractionation was explored for summer-time rain events in Steubenville, Ohio to evaluate the physical processes controlling mercury (Hg) in wet deposition in this industrialized region. Comprehensive precipitation sample collection was conducte...

Climate Change Impacts on Runoff Generation for the Design of Sustainable Stormwater Infrastructure

DOT National Transportation Integrated Search

2011-06-01

Climate change over the Pacific Northwest is expected to alter the hydrological cycle, such as an increase in winter flooding potential due to more precipitation falling as snow and more frequent rain on snow events. Existing infrastructure for storm...

Significance of connectivity and post-wildfire runoff

USDA-ARS?s Scientific Manuscript database

Amplified hillslope soil loss from rain storms following wildfire results from the evolution of runoff and erosion processes across spatial scales. At point to small-plot scales, soil is detached and transported a short distance by rainsplash and sheetflow. Soil transport by water over larger scales...

Flood of January 1997 in the Carson River Basin, California and Nevada

USGS Publications Warehouse

Thomas, Karen A.; Williams, Rhea P.

1997-01-01

In late December 1996, storms built up a large snowpack (more than 180 percent of normal) in the higher altitudes of the Sierra Nevada (Daniel Greenlee, Natural Resource Conservation Service, oral commun., 1997) and also covered the valleys along the eastern Sierra Nevada. Then, a subtropical storm system originating in the central Pacific Ocean near the Hawaiian Islands brought heavy, unseasonably warm rain to the Sierra Nevada from December 30, 1996, through January 2, 1997. During this period, the Natural Resource Conservation Service recorded 16.4 inches (provisional data; Daniel Greenlee, oral commun., 1997) of precipitation at Ebbetts Pass, Calif. (8,700 feet above sea level), and the National Weather Service recorded 3.5 inches (National Oceanic and Atmospheric Administration, National Climate Data Center, written commun., 1997) at Minden (4,710 feet above sea level). Rain falling below about 10,000 feet depleted about 20 percent of the high-altitude snowpack and melted about 80 percent of the snowpack below about 7,000 feet.

Flood of July 2016 in northern Wisconsin and the Bad River Reservation

USGS Publications Warehouse

Fitzpatrick, Faith A.; Dantoin, Eric D.; Tillison, Naomi; Watson, Kara M.; Waschbusch, Robert J.; Blount, James D.

2017-06-06

Heavy rain fell across northern Wisconsin and the Bad River Reservation on July 11, 2016, as a result of several rounds of thunderstorms. The storms caused major flooding in the Bad River Basin and nearby tributaries along the south shore of Lake Superior. Rainfall totals were 8–10 inches or more and most of the rain fell in an 8-hour period. A streamgage on the Bad River near Odanah, Wisconsin, rose from 300 cubic feet per second to a record peak streamflow of 40,000 cubic feet per second in only 15 hours. Following the storms and through September 2016, personnel from the U.S. Geological Survey and Bad River Tribe Natural Resources Department recovered and documented 108 high-water marks near the Bad River Reservation. Many of these high-water marks were used to create three flood-inundation maps for the Bad River, Beartrap Creek, and Denomie Creek for the Bad River Reservation in the vicinity of the community of Odanah.

Airborne radar radiometer measurements of tropical storms

NASA Technical Reports Server (NTRS)

Kumagai, H.; Meneghini, R.; Kozu, T.; Okamoto, K.

1992-01-01

The results from an airborne radar radiometer experiment of rainfall measurement in tropical storms are presented. The experiment was conducted in the Western Pacific in September 1990 with the NASA/DC-8 aircraft which was equipped with a nadir-loking dual-frequency rain radar operating at X band and Ka band, and several channels of microwave radiometers. The X-band radar has a capability of dual-polarization reception which enables the measurements of Linear Depolarization Ratio (LDR). The data of the microwave radiometers are compared with the radar data.

A 20 Ghz Depolarization Experiment Using the ATS-6 Satellite

NASA Technical Reports Server (NTRS)

Bostian, C. W.; Manus, E. A.; Marshall, R. E.; Pendrak, H. N.; Stutzman, W. L.; Wiley, P. H.; Kauffman, S. R.

1975-01-01

A depolarization experiment using the 20 GHz downlink from the ATS-6 satellite was described. The following subjects were covered: (1) an operational summary of the experiment, (2) a description of the equipment used with emphasis on improvements made to the signal processing receiver used with the ATS-5 satellite, (3) data on depolarization and attenuation in one snow storm and two rain storms at 45 deg elevation, (4) data on low angle propagation, (5) conclusions about depolarization on satellite paths, and (6) recommendations for the depolarization portion of the CTS experiment.

ISS Pass Over Hurricane Jose and Hurricane Irma 9/8/17

NASA Image and Video Library

2017-09-08

The International Space Station passed over two major Atlantic hurricanes on Friday, Sept. 8. First, the station flew approximately 250 miles over Hurricane Jose at approximately 10:10 a.m. EDT while the Category 3 storm was in the Atlantic just east of the Caribbean. One orbit of the Earth later, the station flew over Hurricane Irma at approximately 11:40 a.m. EDT. The powerful Category 4 storm had already brought destructive wind and rain to islands across the Caribbean and is forecast to impact the Florida peninsula.

A Look at Hurricane Matthew from NASA AIRS

NASA Image and Video Library

2016-10-06

Hurricane Matthew, currently an extremely dangerous Category 4 storm on the Saffir-Simpson Hurricane Wind Scale, continues to bear down on the southeastern United States. At 11:27 a.m. PDT (2:27 p.m. EDT and 18:23 UT) today, NASA's Atmospheric Infrared Sounder (AIRS) instrument aboard NASA's Aqua satellite observed the storm as its eye was passing over the Bahamas. An AIRS false-color infrared image shows that the northeast and southwest quadrants of the storm had the coldest cloud tops, denoting the regions of the storm where the strongest precipitation was occurring at the time. Data from the Advanced Microwave Sounding Unit (AMSU), another of AIRS' suite of instruments, indicate that the northeast quadrant, which appears smaller in the infrared image, likely had the most intense rain bands at the time. The AIRS infrared image shows that at the time of the image the storm had full circulation, with a small eye surrounded by a thick eye wall and can be seen at http://photojournal.jpl.nasa.gov/catalog/PIA21092.

Proxies of Tropical Cyclone Isotope Spikes in Precipitation: Landfall Site Selection

NASA Astrophysics Data System (ADS)

Lawrence, J. R.; Maddocks, R.

2011-12-01

The human experience of climate change is not one of gradual changes in seasonal or yearly changes in temperature or rainfall. Despite that most paleoclimatic reconstructions attempt to provide just such information. Humans experience climate change on much shorter time scales. We remember hurricanes, weeks of drought or overwhelming rainy periods. Tropical cyclones produce very low isotope ratios in both rainfall and in atmospheric water vapor. Thus, climate proxies that potentially record these low isotope ratios offer the most concrete record of climate change to which humans can relate. The oxygen isotopic composition of tropical cyclone rainfall has the potential to be recorded in fresh water carbonate fossil material, cave deposits and corals. The hydrogen isotopic composition of tropical cyclone rainfall has the potential to be recorded in tree ring cellulose and organic matter in fresh water bodies. The Class of carbonate organisms known as Ostracoda form their carapaces very rapidly. Thus fresh water ephemeral ponds in the subtropics are ideal locations for isotopic studies because they commonly are totally dry when tropical cyclones make landfall. The other proxies suffer primarily from a dilution effect. The water from tropical cyclones is mixed with pre-existing water. In cave deposits tropical cyclone rains mix with soil and ground waters. In the near shore coral environment the rain mixes with seawater. For tree rings there are three sources of water: soil water, atmospheric water vapor that exchanges with leaf water and tropical cyclone rain. In lakes because of their large size rainfall runoff mixes with ground water and preexisting water in the lake. A region that shows considerable promise is Texas / Northeast Mexico. In a study of surface waters that developed from the passage of Tropical Storm Allison (2001) in SE Texas both the pond water and Ostracoda that bloomed recorded the low oxygen isotope signal of that storm (Lawrence et al, 2008). In 2010 rain from Hurricane Alex, Tropical Depression 2 and Tropical Storm Hermine flooded ephemeral ponds in south Texas. Isotopic analysis of water and fossil Ostracoda from ephemeral ponds in south Texas is planned. Cores (50 cm in length) were taken in one of these ponds where living Ostracoda were found and collected.

Assessing Hurricane Katrina Vegetation Damage at Stennis Space Center using IKONOS Image Classification Techniques

NASA Technical Reports Server (NTRS)

Spruce, Joseph P.; Ross, Kenton W.; Graham, William D.

2007-01-01

Hurricane Katrina hit southwestern Mississippi on August 29, 2005, at 9:45 a.m. CDT as a category 3 storm with surges up to approx. 9 m and sustained winds of approx. 120 mph. The hurricane's wind, rain, and flooding devastated several coastal towns, from New Orleans through Mobile. The storm also caused significant damage to infrastructure and vegetation of NASA's SSC (Stennis Space Center). Storm recovery at SSC involved not only repairs of critical infrastructure but also forest damage mitigation (via timber harvests and control burns to reduce fire risk). This presentation discusses an effort to use commercially available high spatial resolution multispectral IKONOS data for vegetation damage assessment, based on data collected over SSC on September 2, 2005.

Real-time landslide warning during heavy rainfall

USGS Publications Warehouse

Keefer, D.K.; Wilson, R.C.; Mark, R.K.; Brabb, E.E.; Brown, W. M.; Ellen, S.D.; Harp, E.L.; Wieczorek, G.F.; Alger, C.S.; Zatkin, R.S.

1987-01-01

A real-time system for issuing warnings of landslides during major storms is being developed for the San Francisco Bay region, California. The system is based on empirical and theoretical relations between rainfall and landslide initiation, geologic determination of areas susceptible to landslides, real-time monitoring of a regional network of telemetering rain gages, and National Weather Service precipitation forecasts. This system was used to issue warnings during the storms of 12 to 21 February 1986, which produced 800 millimeters of rainfall in the region. Although analysis after the storms suggests that modifications and additional developments are needed, the system successfully predicted the times of major landslide events. It could be used as a prototype for systems in other landslide-prone regions.

Event Water Balance and Recharge at the Panola Mountain Research Watershed, Georgia, U.S.A.

NASA Astrophysics Data System (ADS)

Riley, J. W.; Aulenbach, B. T.

2016-12-01

Investigating catchment storage and runoff pathways allows a better mechanistic understanding of stream flow generation processes. This information can be used to elucidate processes such as those influencing baseflow that support human consumption and ecological needs. Here we describe storm runoff water budgets from 483 rain events to determine the conditions under which precipitation infiltrates to deeper storage that supports baseflow. Further, we examine the storage and recharge behavior of different storm characteristics and antecedent conditions. We use a simple water budget approach to achieve this in which Deep Recharge = (Precipitation) - (Storm Runoff) - (Event Change in Soil Storage). Hydrograph separation was used to determine the storm periods and split storm runoff into baseflow and quickflow. Quickflow was assumed to account for the event water lost to the stream. Data from volumetric water content sensors were used to calculate the soil profile water storage and the change in water storage over the course of an event. The remaining water after these two components was assumed to represent water available for deeper recharge. The median event quickflow:precipitation ratio was 11.8%. Event soil moisture recharge in the top one meter of soil accounted for a median of 65.3% of precipitation. Quickflow and shallow soil moisture recharge accounted for a median of 77.1% of the precipitation delivered to the watershed. Water budgets indicated that 43% of the events provided water for deeper recharge. Of these events, however, only 28% provided 50 mm or more of deep recharge. Because the focus was on events, when humidity was high and the vapor pressure deficit (VPD) was low, we ignored the role of evapotranspiration. However, interception, which was not accounted for, would have resulted in less storm precipitation than was measured at the watershed rain gage. Furthermore, transpiration may have altered the post-storm water balance when VPD increased and before excess water was able to infiltrate to deeper storage. While uncertainty remains, this study provided insight into the partitioning of incoming precipitation and the conditions under which water was likely available for deeper recharge.

Rainy Weather Science.

ERIC Educational Resources Information Center

Reynolds, Karen

1996-01-01

Presents ideas on the use of rainy weather for activities in the earth, life, and physical sciences. Topics include formation and collision of raindrops, amount and distribution of rain, shedding of water by plants, mapping puddles and potholes, rainbow formation, stalking storms online, lightning, and comparing particles in the air before and…

KSC-01pp1362

NASA Image and Video Library

2001-07-19

KENNEDY SPACE CENTER, Fla. -- The P5 truss rolls into the Spaceport Florida hangar just before a rain storm. The truss eventually will be transported to the Space Station Processing Facility. The P5 is scheduled for delivery to the International Space Station on mission 12A.1 in April 2003

Response of Spartina Alterniflora to Sea Level Rise, Changing Precipitation Patterns, and Eutrophication

EPA Science Inventory

Sea level rise, precipitation, and eutrophication (3 X 3 X 2 factorial design) were simulated in tidal mesocosms in the US EPA Narragansett greenhouse. Each precipitation treatment (storm, drought, ambient rain) was represented in one of two tanks (control, fertilized). The contr...

KSC-02pd0995

NASA Image and Video Library

2002-06-18

KENNEDY SPACE CENTER, FLA. -- Black storm clouds hang over the Vehicle Assembly Building and Launch Control Center, bringing thunder and heavy rain to the area. This type of weather convinced flight control managers to wave off the two scheduled landing attempts at KSC for Endeavour, returning from mission STS-111

PROSPECTS FOR ENHANCED GROUNDWATER RECHARGE VIA INFILTRATION OF URBAN STORMWATER RUNOFF: A CASE STUDY

EPA Science Inventory

The rain garden is an urban storm water best management practice that is used to infiltrate runoff close to its source, thereby disconnecting impervious area while providing an avenue for groundwater recharge. Groundwater recharge may provide additional benefits to aquatic ecosys...

Estimation of the rain signal in the presence of large surface clutter

NASA Technical Reports Server (NTRS)

Ahamad, Atiq; Moore, Richard K.

1994-01-01

The principal limitation for the use of a spaceborne imaging SAR as a rain radar is the surface-clutter problem. Signals may be estimated in the presence of noise by averaging large numbers of independent samples. This method was applied to obtain an estimate of the rain echo by averaging a set of N(sub c) samples of the clutter in a separate measurement and subtracting the clutter estimate from the combined estimate. The number of samples required for successful estimation (within 10-20%) for off-vertical angles of incidence appears to be prohibitively large. However, by appropriately degrading the resolution in both range and azimuth, the required number of samples can be obtained. For vertical incidence, the number of samples required for successful estimation is reasonable. In estimating the clutter it was assumed that the surface echo is the same outside the rain volume as it is within the rain volume. This may be true for the forest echo, but for convective storms over the ocean the surface echo outside the rain volume is very different from that within. It is suggested that the experiment be performed with vertical incidence over forest to overcome this limitation.

Promoting nitrate removal in rain gardens | Science Inventory ...

EPA Pesticide Factsheets

Rain gardens are vegetated surface depressions, often located at low points in landscapes, designed to receive stormwater runoff from roads, roofs, and parking lots. The gardens’ sandy soils allow stormwater to drain quickly to the native soils below and eventually to groundwater. The rain garden vegetation and soils remove pollutants and nutrients from stormwater runoff through biological and physical processes such as plant uptake and sorption to soil particles. In comparison with stormwater release to receiving waters through conventional storm drain systems, infiltrating stormwater through rain gardens reduces peak flows and loadings of both pollutants and nutrients. This reduction improves the physical and biological integrity of receiving streams by reducing stream bank erosion and negative effects on stream communities. While local governments and individual homeowners are building these systems, relatively few scientific studies have documented the ability of rain gardens to remove pollutants and nutrients. This U.S. EPA long-term research project investigates: 1) the performance of rain gardens in removing pollutants, and 2) whether currently-accepted design standards can be adjusted to improve nitrate removal capabilities. Typical rain garden designs provide large removals of pollutants of concern, including heavy metals, phosphorus, total nitrogen, and ammonium. The gardens have been less successful in removing nitrate, an importan

Throughfall Monitoring Of Old Growth, Second Growth, And Cleared Vegetation Plots On Prince of Wales Island, Alaska

NASA Astrophysics Data System (ADS)

Prussian, K. M.

2006-12-01

The density of forest canopy affects the amount of rain reaching the forest floor in forested environments of Southeast Alaska. Less throughfall occurs in the second growth sites than in the old growth site and greater throughfall occurs in the clear-cut sites. More specifically, preliminary data show that SG sites received between 38 and 87% of the OG throughfall and the clear-cut sites experienced between 145 and 248% of the OG throughfall. Precipitation gages were used to monitor throughfall in each of the forested vegetation sites on Prince of Wales Island, Alaska, as an indicator of the amount of water reaching the forest floor in these different forest types. Data collected during 2004 and 2005 included 23 storms ranging from 0.2 to 10.6 inches of rain in the clear-cut forest. This monitoring is an effort to determine the affect, if any, that forest management could have on throughfall, and furthermore, lend information to forest management effects on the water balance within a watershed. Site selection focused on similarities in location, elevation, aspect, and accessibility while accounting for the three varying vegetation conditions. Data collected during 2004 and 2005 sampling seasons were in the same sampling plots, while data collected in 2006 is a duplicate set of sites. Twenty-three storms were used to determine the affect, if any, that forest management could have on throughfall, and furthermore, lend information to forest management effects on the water balance within a watershed. The second growth stand was harvested in 1979 and is currently in stem re-initiation phase with thick conifer regeneration. The clear-cut site was harvested in 1999 and contains conifer vegetation, blueberry, and salmonberry vegetation less than five feet in height. Storms were defined as events that were clearly delineated by lack of rainfall for a period of time, or similar antecedent conditions, and totaled at least .2 inches of rain at the CC site. Analysis of a storm event began prior to rainfall (in the CC site) and terminated post throughfall in the SG sites.

Illuminating wildfire erosion and deposition patterns with repeat terrestrial lidar

USGS Publications Warehouse

Rengers, Francis K.; Tucker, G.E.; Moody, J.A.; Ebel, Brian

2016-01-01

Erosion following a wildfire is much greater than background erosion in forests because of wildfire-induced changes to soil erodibility and water infiltration. While many previous studies have documented post-wildfire erosion with point and small plot-scale measurements, the spatial distribution of post-fire erosion patterns at the watershed scale remains largely unexplored. In this study lidar surveys were collected periodically in a small, first-order drainage basin over a period of 2 years following a wildfire. The study site was relatively steep with slopes ranging from 17° to > 30°. During the study period, several different types of rain storms occurred on the site including low-intensity frontal storms (2.4 mm h−1) and high-intensity convective thunderstorms (79 mm h−1). These storms were the dominant drivers of erosion. Erosion resulting from dry ravel and debris flows was notably absent at the site. Successive lidar surveys were subtracted from one another to obtain digital maps of topographic change between surveys. The results show an evolution in geomorphic response, such that the erosional response after rain storms was strongly influenced by the previous erosional events and pre-fire site morphology. Hillslope and channel roughness increased over time, and the watershed armored as coarse cobbles and boulders were exposed. The erosional response was spatially nonuniform; shallow erosion from hillslopes (87% of the study area) contributed 3 times more sediment volume than erosion from convergent areas (13% of the study area). However, the total normalized erosion depth (volume/area) was highest in convergent areas. From a detailed understanding of the spatial locations of erosion, we made inferences regarding the processes driving erosion. It appears that hillslope erosion is controlled by rain splash (for detachment) and overland flow (for transport and quasi-channelized erosion), with the sites of highest erosion corresponding to locations with the lowest roughness. By contrast, in convergent areas we found erosion caused by overland flow. Soil erosion was locally interrupted by immobile objects such as boulders, bedrock, or tree trunks, resulting in a patchy erosion network with increasing roughness over time.

Hurricane Imaging Radiometer Wind Speed and Rain Rate Retrievals during the 2010 GRIP Flight Experiment

NASA Technical Reports Server (NTRS)

Sahawneh, Saleem; Farrar, Spencer; Johnson, James; Jones, W. Linwood; Roberts, Jason; Biswas, Sayak; Cecil, Daniel

2014-01-01

Microwave remote sensing observations of hurricanes, from NOAA and USAF hurricane surveillance aircraft, provide vital data for hurricane research and operations, for forecasting the intensity and track of tropical storms. The current operational standard for hurricane wind speed and rain rate measurements is the Stepped Frequency Microwave Radiometer (SFMR), which is a nadir viewing passive microwave airborne remote sensor. The Hurricane Imaging Radiometer, HIRAD, will extend the nadir viewing SFMR capability to provide wide swath images of wind speed and rain rate, while flying on a high altitude aircraft. HIRAD was first flown in the Genesis and Rapid Intensification Processes, GRIP, NASA hurricane field experiment in 2010. This paper reports on geophysical retrieval results and provides hurricane images from GRIP flights. An overview of the HIRAD instrument and the radiative transfer theory based, wind speed/rain rate retrieval algorithm is included. Results are presented for hurricane wind speed and rain rate for Earl and Karl, with comparison to collocated SFMR retrievals and WP3D Fuselage Radar images for validation purposes.

Importance of structural stability to success of mourning dove nests

USGS Publications Warehouse

Coon, R.A.; Nichols, J.D.; Percival, H.F.

1981-01-01

Studies of nest-site selection and nesting habitats often involve a "characterization" of nests and of habitats in which nests are found. Our objective in the present work is to identify nest-site characteristics that are associated with variation in components of Mourning Dove (Zenaida macroura) fitness (e.g. the probability of a nest succeeding), as opposed to simply "characterizing" dove nest sites. If certain nest- site characteristics affect the probability that a nest will succeed, then we suspect that these characteristics will be associated with either concealment (the probability of detection by certain predators) or structural stability (the probability of eggs or entire nests falling to the ground as a result of wind, rain storms, parental activity, etc.). Although other workers agree that structural stability is an important determinant of Mourning Dove nesting success (e.g. McClure 1944: 384; Woolfenden and Rohwer 1969: 59), we are aware of no actual tests of this hypothesis.

A UK portrait of wind-induced undercatch in rainfall measurement

NASA Astrophysics Data System (ADS)

Pollock, Michael; Quinn, Paul; O'Donnell, Greg; Colli, Matteo; Dutton, Mark; Black, Andrew; Wilkinson, Mark; Kilsby, Chris; Stagnaro, Mattia; Lanza, Luca; O'Connell, Enda

2017-04-01

Rainfall is vital to life; civilisation depends upon it. Changing local and regional rainfall regimes toward more intense storm events (e.g. in the UK), increases the existing challenge of accurately measuring and modelling rainfall. Data from rain gauges, often considered to provide the most accurate practicable measure of precipitation at a point in space in time, play a critical role. They are used for, inter alia, flood forecasting and flood risk management; radar calibration and numerical weather prediction models; urban planning and drainage; and water resource management and hydrological modelling. Despite the key importance of these measurements, they remain susceptible to fundamental sources of systematic error which are often not considered when rainfall data are used. Inaccuracies in measurements are compounded in modelling applications by producing potentially misleading or incorrect results; it is therefore of great importance to understand and present uncertainty in observations. Standard practice is to mount rain gauges above the ground surface. This configuration obstructs the prevailing wind which causes an acceleration of airflow above the orifice. Precipitation is deflected away from the orifice and lands 'downstream' of the area represented by the gauge measurement, reducing its collection efficiency (CE). This phenomenon is commonly referred to as 'wind-induced undercatch'. The physical shape of a gauge bears a significant impact on its CE. Computational Fluid Dynamics (CFD) simulations are used to investigate how different shapes of precipitation gauge are affected by the wind. CFD modelling is supported by high-resolution field measurements at several exposed 'Hydro-Met' research stations in the UK. These sites are occupied by rain gauges which are scrutinised in the CFD analyses. The reference measurements at all sites are made within a WMO reference pit, where the rain gauge is mounted with its orifice at ground level and surrounded by an appropriate grid structure. 'Undercatch' exhibited within UK storms, not captured by operational gauge networks in the UK, is quantified and presented in this study. Results from CFD modelling and the field studies show that gauge shape and mounting height significantly affect the extent of the undercatch. 'Aerodynamic' gauges following a 'champagne flute' or a 'funnel' profile were demonstrated by both to have significant advantages over conventional gauge shapes, in terms of improving the CE. This study presents the latest analyses, and proposes the possible extent of rainfall underestimation within the UK, with particular reference to its hydrology.

Eureka!

ERIC Educational Resources Information Center

Villano, Matt

2009-01-01

Academic technologists at Lynn University (Florida) learned the hard way just how important a disaster recovery plan can be. Back in 2005, when Hurricane Wilma walloped the region with driving rain and 120 mile-per-hour winds, the storm debilitated Lynn's IT department, causing damage and flooding that thwarted the campus network for nearly two…

KSC-2011-2584

NASA Image and Video Library

2011-03-31

CAPE CANAVERAL, Fla. – At NASA's Kennedy Space Center in Florida, an ominous thunderstorm cloud hovers over the Vehicle Assembly Building in the Launch Complex 39 area. Severe storms associated with a frontal system are moving through Central Florida, producing strong winds, heavy rain, frequent lightning and even funnel clouds. Photo credit: NASA/Kim Shiflett

KSC-2011-2640

NASA Image and Video Library

2011-03-31

CAPE CANAVERAL, Fla. – At NASA's Kennedy Space Center in Florida, dark clouds hover over the Vehicle Assembly Building in the Launch Complex 39 area. Severe storms associated with a frontal system are moving through Central Florida, producing strong winds, heavy rain, frequent lightning and even funnel clouds. Photo credit: NASA/Jack Pfaller

KSC-2011-2641

NASA Image and Video Library

2011-03-31

CAPE CANAVERAL, Fla. – At NASA's Kennedy Space Center in Florida, dark clouds hover over the Vehicle Assembly Building in the Launch Complex 39 area. Severe storms associated with a frontal system are moving through Central Florida, producing strong winds, heavy rain, frequent lightning and even funnel clouds. Photo credit: NASA/Jack Pfaller

What Happens during a Thunderstorm?

ERIC Educational Resources Information Center

Mogil, H. Michael

2004-01-01

A thunderstorm is a localized storm accompanied by lightning and thunder. It may also have gusty winds and often brings heavy rain. Some thunderstorms can also bring tornadoes and/or hail. During winter, localized heavy snow showers may also have thunder and lightning. And, in the western United States in summer, thunderstorms may be…

TEMPORAL VARIABILITY IN PHYSICAL SPECIATION OF METALS DURING A WINTER RAIN-ON-SNOW EVENT

EPA Science Inventory

Particulate matter in urban rivers transports a significant fraction of pollutants, changes rapidly during storm events and is difficult to characterize. In this study, the physical speciation of trace metals and organic carbon in an urban river and upstream headwaters site in To...

Wet weather impact on trihalomethane formation potential in tributaries to drinking water reservoirs.

PubMed

Alkhatib, E; Peters, R

2008-04-01

During rain storm events, land surface runoff and resuspension of bottom sediments cause an increase in Trihalomethane (THM) precursors in rivers. These precursors, when chlorinated at water treatment facilities will lead to the formation of THMs and hence impact drinking water resources. In order to evaluate the wet weather impact on the potential formation of THMs, river samples were collected before, during and after three rain storms ranging from 15.2 to 24.9 mm precipitation. The samples were tested for THM formation potential and other indicators including UV254 absorbance, turbidity and volatile suspended solid (VSS). Average levels of THMs increased from 61 microg/l during dry weather to 131 microg/l during wet weather, and then went back to 81 microg/l after rain ended. Wet weather values of THM are well above the maximum contaminant level (MCL) 80 microg/l, set by EPA for drinking water. THM indicators also exhibited similar trends. Average levels increased from 0.6 to 1.8 abs; 2.6 to 6 ntu; and 7.5 to 15 mg/l respectively for UV254, turbidity and VSS. A positive correlation was observed between THM formation and THM indicators. The t-test of significance (p-value) was less than 0.05 for all indicators, and R values ranged from 0.85 to 0.92 between THMs and the indicators, and 0.72 to 0.9 among indicators themselves.

The "Weekend Effect" in Summertime U.S. Rainfall: Evidence for Midweek Intensification of Storms by Pollution

NASA Astrophysics Data System (ADS)

Bell, T. L.; Rosenfeld, D.; Kim, K.; Hahnenberger, M.

2006-05-01

Persistent and strong dependence of rain rate on the day of the week has been found in Tropical Rainfall Measuring Mission (TRMM) satellite estimates of summer afternoon rainfall over the southeast U.S. and the nearby Atlantic from 1998 to 2005. Midweek (Tue--Thu) rain rates and rain area appear to increase over land, and this increase is accompanied by a corresponding diminution of rainfall over nearby waters. Reanalysis data from atmospheric models suggest that there is a corresponding weekly variation in atmospheric winds consistent with the changes in rainfall. These variations are almost certainly caused by weekly variations in human activity. The most likely cause of the observed changes in rainfall is the well documented weekly variation in atmospheric pollution. Particulate pollution is highest in the middle of the week. Considerable observational and modeling evidence has accumulated concerning the effects of aerosols on precipitation. Most of this evidence relates to the suppression of precipitation by aerosols, but it has been argued that storms in highly unstable moist environments can be invigorated by aerosols, and some modeling studies seem to confirm this. The strong weekly cycle in rainfall observed over the southeast U.S. along with what appears to be dynamical suppression of rainfall over the nearby Atlantic, and the lack of an observable cycle over the southwest U.S., are consistent with this theory.

Weekend Effect" in Summertime U.S. Rainfall: Evidence for Midweek Intensification of Storms by Pollution

NASA Technical Reports Server (NTRS)

Bell, Thomas L.; Rosenfeld, Daniel; Kim, Kyu-Myong; Hahnenberger, Maura

2006-01-01

Persistent and strong dependence of rain rate on the day of the week has been found in Tropical Rainfall Measuring Mission (TRMM) satellite estimates of summer afternoon rainfall over the southeast U.S. and the nearby Atlantic from 1998 to 2005. Midweek (Tue-Thu) rain rates and rain area appear to increase over land, and this increase is accompanied by a corresponding diminution of rainfall over nearby waters. Reanalysis data from atmospheric models, suggest that there is a corresponding weekly variation in atmospheric winds consistent with the changes in rainfall. These variations are almost certainly caused by weekly variations in human activity. The most likely cause of the observed changes in rainfall is the well documented weekly variation in atmospheric pollution. Particulate pollution is highest in the middle of the week. Considerable observational and modeling evidence has accumulated concerning the effects of aerosols on precipitation. Most of this evidence relates to the suppression of precipitation by aerosols, but it has been argued that storms in highly unstable moist environments can be invigorated by aerosols, and some modeling studies seem to confirm this. The strong weekly cycle in rainfall observed over the southeast U.S. along with what appears to be dynamical suppression of rainfall over the nearby Atlantic, and the lack of an observable cycle over the southwest U.S., are consistent with this theory.

Tropical storms and the flood hydrology of the central Appalachians

NASA Astrophysics Data System (ADS)

Sturdevant-Rees, Paula; Smith, James A.; Morrison, Julia; Baeck, Mary Lynn

2001-08-01

Flooding from Hurricane Fran is examined as a prototype for central Appalachian flood events that dominate the upper tail of flood peak distributions at basin scales between 100 and 10,000 km2. Hurricane Fran, which resulted in 34 deaths and more than $3.2 billion in damages, made land fall on the North Carolina coast at 0000 UTC, September 6, 1996. By 1200 UTC on September 6, Fran had weakened to a tropical storm, and the center of circulation was located at the North Carolina-Virginia border. Rain bands surrounding the tropical depression produced extreme rainfall and flooding in Virginia and West Virginia, with the most intense rainfall concentrated near ridge tops in the Blue Ridge and Valley and Ridge physiographic provinces. The most severe flooding occurred in the Shenandoah River watershed of Virginia, where peak discharges exceeded the 100-year magnitude at 11 of 19 U.S. Geological Survey stream-gaging stations. The availability of high-resolution discharge and rainfall data sets provides the opportunity to study the hydrologic and hydrometeorological mechanisms associated with extreme floods produced by tropical storms. Analyses indicate that orographie enhancement of tropical storm precipitation plays a central role in the hydrology of extreme floods in the central Appalachian region. The relationships between drainage network structure and storm motion also play a major role in Appalachian flood hydrology. Runoff processes for Hurricane Fran reflected a mixture of saturation excess and infiltration excess mechanisms. Antecedent soil moisture played a significant role in the hydrology of extreme flooding from Hurricane Fran. Land use, in particular, the presence of forest cover, was of secondary importance to the terrain-based distribution of precipitation in determining extreme flood response.

Evaluation of GPM candidate algorithms on hurricane observations

NASA Astrophysics Data System (ADS)

Le, M.; Chandrasekar, C. V.

2012-12-01

The observation of precipitation on a global scale by the Tropical Rain Measuring Mission (TRMM) precipitation radar (PR) and has enabled a large scale study of precipitation over ocean, especially tropical storms. The three-dimensional downward-looking observation characteristic of the TRMM-PR makes it possible to study the vertical structure of tropical storms. The global precipitation measuring mission (GPM) will be the second mission following the success of TRMM. The GPM Mission extends tropical storm tracking and forecasting capabilities into the middle and high latitudes, covering the area from 65° S to 65°N. This orbit will provide new insight into how and why some tropical storm intensify and others weaken as they move from tropical to mid-latitude systems. The GPM core satellite will be equipped with a dual-frequency precipitation radar (DPR) operating at K_u (13.6 GHz) and K_a (35.5 GHz) band. DPR on aboard the GPM core satellite is expected to improve our knowledge of precipitation processes relative to the single-frequency (K_u band) radar used in TRMM by providing greater dynamic range, more detailed information on microphysics, and better accuracies in rainfall retrievals. New K_a band channel observation of DPR will help to improve the detection thresholds for light rain and snow relative to TRMM PR [1]. The dual-frequency signals will allow us to better distinguish regions of liquid, frozen, and mixed-phase precipitation. In the GPM era, storms could be better tracked and characterized. In support the NASA GPM mission, NASA JPL (Jet Propulsion Lab) developed the 2nd generation Airborne Precipitation Radar (APR-2) as a prototype of advanced dual-frequency space radar which emulates DPR on board the GPM core satellite before it is launched. GRIP (Genesis and Rapid Intensification Processes) is the most recent campaign of APR-2 conducted in the year 2010 located in Golf of Mexico and Caribbean sea with the major goal to better understand tropical storms and hurricanes. In this paper, the performance of GPM candidate algorithms [2][3] to perform profile classification, melting region detection as well as drop size distribution retrieval for hurricane Earl will be presented. This analysis will be compared with other storm observations that are not tropical storms. The philosophy of the algorithm is based on the vertical characteristic of measured dual-frequency ratio (DFRm), defined as the difference in measured radar reflectivities at the two frequencies. It helps our understanding of how hurricanes such as Earl form and intensify rapidly. Reference [1] T. Iguchi, R. Oki, A. Eric and Y. Furuhama, "Global precipitation measurement program and the development of dual-frequency precipitation radar," J. Commun. Res. Lab. (Japan), 49, 37-45.2002. [2] M. Le and V. Chandrasekar, Recent updates on precipitation classification and hydrometeor identification algorithm for GPM-DPR, Geoscience science and remote sensing symposium, IGARSS'2012, IEEE International, Munich, Germany. [3] M. Le ,V. Chandrasekar and S. Lim, Microphysical retrieval from dual-frequency precipitation radar board GPM, Geoscience science and remote sensing symposium, IGARSS'2010, IEEE International, Honolulu, USA.

A rain splash transport equation assimilating field and laboratory measurements

USGS Publications Warehouse

Dunne, T.; Malmon, D.V.; Mudd, S.M.

2010-01-01

Process-based models of hillslope evolution require transport equations relating sediment flux to its major controls. An equation for rain splash transport in the absence of overland flow was constructed by modifying an approach developed by Reeve (1982) and parameterizing it with measurements from single-drop laboratory experiments and simulated rainfall on a grassland in East Africa. The equation relates rain splash to hillslope gradient, the median raindrop diameter of a storm, and ground cover density; the effect of soil texture on detachability can be incorporated from other published results. The spatial and temporal applicability of such an equation for rain splash transport in the absence of overland flow on uncultivated hillslopes can be estimated from hydrological calculations. The predicted transport is lower than landscape-averaged geologic erosion rates from Kenya but is large enough to modify short, slowly eroding natural hillslopes as well as microtopographic interrill surfaces between which overland flow transports the mobilized sediment. Copyright 2010 by the American Geophysical Union. Copyright 2010 by the American Geophysical Union.

Enhanced object-based tracking algorithm for convective rain storms and cells

NASA Astrophysics Data System (ADS)

Muñoz, Carlos; Wang, Li-Pen; Willems, Patrick

2018-03-01

This paper proposes a new object-based storm tracking algorithm, based upon TITAN (Thunderstorm Identification, Tracking, Analysis and Nowcasting). TITAN is a widely-used convective storm tracking algorithm but has limitations in handling small-scale yet high-intensity storm entities due to its single-threshold identification approach. It also has difficulties to effectively track fast-moving storms because of the employed matching approach that largely relies on the overlapping areas between successive storm entities. To address these deficiencies, a number of modifications are proposed and tested in this paper. These include a two-stage multi-threshold storm identification, a new formulation for characterizing storm's physical features, and an enhanced matching technique in synergy with an optical-flow storm field tracker, as well as, according to these modifications, a more complex merging and splitting scheme. High-resolution (5-min and 529-m) radar reflectivity data for 18 storm events over Belgium are used to calibrate and evaluate the algorithm. The performance of the proposed algorithm is compared with that of the original TITAN. The results suggest that the proposed algorithm can better isolate and match convective rainfall entities, as well as to provide more reliable and detailed motion estimates. Furthermore, the improvement is found to be more significant for higher rainfall intensities. The new algorithm has the potential to serve as a basis for further applications, such as storm nowcasting and long-term stochastic spatial and temporal rainfall generation.

The role of SSTs in the development of explosive cyclogenesis: The storm of 21-22 January 2004 in the Eastern Mediterranean

NASA Astrophysics Data System (ADS)

Katsafados, P.; Mavromatidis, E.; Papadopoulos, A.; Pytharoulis, I.

2009-09-01

During the last two decades much attention has been given to the extra-tropical cyclonic systems that develop at an unusually rapid rate. The first synoptic and climatological study of such explosively developing storm has been documented by Sanders and Gyakum (1980). They defined an extra-tropical cyclone as "bomb" when its central sea-level pressure deepens by at least 1hPa per hour for 24 hours at a latitude of 60 0N. Strong sea surface temperature (SST) gradients accompanied with high surface fluxes of heat (latent and sensible) appear to characterize the favorable environment for the marine bomb development. Various modeling studies seem to suggest different roles of the SST and heat flux in forcing the extra-tropical atmosphere. Although models are sensitive to the lower boundary conditions, it is not clear if the forcing from different types of SST can significantly impact a given simulation of a rapid developing cyclonic system. To this end, comparative numerical simulations of an explosive cyclogenesis event in marine environment were performed based on a non-hydrostatic limited area model. Reanalysis and satellite-measured SSTs were both used as model lower boundary conditions. The aim of this study is to investigate the sensitivity of storm characteristics to the different SST sources. The case of 21-22 January 2004 was chosen for analysis due to its intensity and impact in the coastal areas of Southern Greece. According to the MEDEX database (MEDiteranean EXperiment) this event was among the three deepest cyclones found in the entire Mediterranean during last decades. Model simulations on high spatiotemporal resolution resolved mesoscale features triggered by the different nature of SSTs. Although the atmospheric response was significant in terms of rain bands and surface fluxes, the phase and the structure of the system were not affected by the different boundary conditions forcing. In more details, the shifted rain bands, as they were simulated with reanalysis and satellite-measured SST forcing, are related with the different representation of the transition speed of the storm. These precipitation patterns are mainly attributed to the stronger surface fluxes of heat that impose a deeper destabilization of the boundary layer. Stronger surface fluxes, with differences exceeding 150 Wm-2, were predicted when the generally warmer reanalysis SSTs were used.

Hurricane hazards: a national threat

USGS Publications Warehouse

,

2005-01-01

Hurricanes bring destructive winds, storm surge, torrential rain, flooding, and tornadoes. A single storm can wreak havoc on coastal and inland communities and on natural areas over thousands of square miles. In 2005, Hurricanes Katrina, Rita, and Wilma demonstrated the devastation that hurricanes can inflict and the importance of hurricane hazards research and preparedness. More than half of the U.S. population lives within 50 miles of a coast, and this number is increasing. Many of these areas, especially the Atlantic and Gulf coasts, will be in the direct path of future hurricanes. Hawaii is also vulnerable to hurricanes.

Texas after Tropical Storm Allison (bands 2,1,3 in R,G,B)

NASA Technical Reports Server (NTRS)

2002-01-01

This MODIS image of Texas (left), Oklahoma (top left), Louisiana (bottom right) and Arkansas (upper right) makes use of band combinations (groups of wavelengths) that make water stand out against land. In this image, the dark blue/black squiggles indicate water. The bright green area along the Texas coast is Galveston Bay, southeast of Houston. Houston was devastated in the past week from the rains from Tropical Storm Allison. The brightness of the Bay may be due to sediment runoff from all the floodwaters. Credit: Jacques Descloitres, MODIS Land Rapid Response Team

Examining the causes of a devastating debris flow

NASA Astrophysics Data System (ADS)

Balcerak, Ernie

2014-08-01

Storm-triggered landslides cause loss of life, property damage, and landscape alterations. For instance, the remnants of Hurricane Camille in 1969 caused 109 deaths in central Virginia, after 600 millimeters of rain fell in mountainous terrain in 6 hours. More recently, on 8 August 2010, a rainstorm-induced landslide devastated the Chinese county of Zhouqu, causing more than 1000 deaths. A new modeling study by Ren examines the multiple factors, natural and human caused, that came together to produce this event. Three things contribute to storm-triggered landslides: geological condition, surface loading and vegetation roots, and extreme precipitation.

Rainfall and runoff quantity and quality characteristics of four urban land-use catchments in Fresno, California, October 1981 to April 1983

USGS Publications Warehouse

Oltmann, Richard N.; Shulters, Michael V.

1989-01-01

Rainfall and runoff quantity and quality were monitored for industrial, single-dwelling residential, multiple-dwelling residential, and commercial land-use catchments during the 1981-82 and 1982-83 rain seasons. Storm-composite rainfall and discrete run6ff samples were analyzed for numerous inorganic, biological, physical, and organic constituents. Atmospheric dry-deposition and street-surface particulate samples also were collected and analyzed. With the exception of the industrial catchment, the highest runoff concentrations for most constituents occurred during the initial storm runoff and then decreased throughout the remainder of the storm, independent of hydraulic conditions. Metal concentrations were high during initial runoff, but also increased as flow increased. Constituent concentrations for the industrial catchment fluctuated greatly during storms. Statistical tests showed higher ammonia plus organic nitrogen, ammonia, pH, and phenol concentrations in rainfall at the industrial site than at the single-dwelling residential and laboratory sites. Statistical testing of runoff quality data showed higher concentrations for the industrial catchment than for the two residential and commercial catchments for most constituents. Total recoverable lead was one of the few constituents that had lower concentrations for the industrial catchment than for the other three catchments. The two residential catchments showed no significant difference in runoff concentrations for 50 of the 57 constituents used in the statistical analysis. The commercial catchment runoff concentrations for most constituents generally were similar to the residential catchments. Although constituent concentrations generally were higher for the industrial catchment than for the commercial catchment, constituent storm loads from the commercial catchment were similar to the industrial catchment because of the greater runoff volume from the highly impervious commercial catchment. Between 10 and 50 percent of the constituent runoff loads for the two residential catchments were attributed to the rainfall load, with the percentages generally considerably less for the industrial catchment. Event mean concentrations (EMC) for most constituents for all but the industrial catchment were highest for the first two or three storms of the rain season after which they became almost constant. Constituent event mean concentrations for the industrial catchment generally did not show any pattern throughout a rain season. Multiple-regression predictor equations for event mean concentrations were developed for several constituents for all sites. Average annual constituent unit loads were computed for 18 constituents for each catchment. The organophosphorus compounds, diazinon, malathion, and parathion were the most prevalent pesticides detected in rainfall. Diazinon was detected in all 54 rainfall samples. Parathion and malathion were detected in 49 and 50 samples, respectively. Other pesticides detected in rainfall included chlordane, lindane, methoxychlor, endosulfan, and 2,4-D. Of these, only methoxychlor and endosulfan were not consistently detected in runoff.

Understanding climate variability and global climate change using high-resolution GCM simulations

NASA Astrophysics Data System (ADS)

Feng, Xuelei

In this study, three climate processes are examined using long-term simulations from multiple climate models with increasing horizontal resolutions. These simulations include the European Center for Medium-range Weather Forecasts (ECMWF) atmospheric general circulation model (AGCM) runs forced with observed sea surface temperatures (SST) (the Athena runs) and a set of coupled ocean-atmosphere seasonal hindcasts (the Minerva runs). Both sets of runs use different AGCM resolutions, the highest at 16 km. A pair of the Community Climate System Model (CCSM) simulations with ocean general circulation model (OGCM) resolutions at 100 and 10 km are also examined. The higher resolution CCSM run fully resolves oceanic mesoscale eddies. The resolution influence on the precipitation climatology over the Gulf Stream (GS) region is first investigated. In the Athena simulations, the resolution increase generates enhanced mean GS precipitation moderately in both large-scale and sub-scale rainfalls in the North Atlantic, with the latter more tightly confined near the oceanic front. However, the non-eddy resolving OGCM in the Minerva runs simulates a weaker oceanic front and weakens the mean GS precipitation response. On the other hand, an increase in CCSM oceanic resolutions from non-eddy-resolving to eddy resolving regimes greatly improves the model's GS precipitation climatology, resulting in both stronger intensity and more realistic structure. Further analyses show that the improvement of the GS precipitation climatology due to resolution increases is caused by the enhanced atmospheric response to an increased SST gradient near the oceanic front, which leads to stronger surface convergence and upper level divergence. Another focus of this study is on the global warming impacts on precipitation characteristic changes using the high-resolution Athena simulations under the SST forcing from the observations and a global warming scenario. As a comparison, results from the coarse resolution simulation are also analyzed to examine the dependence on resolution. The increasing rates of globally averaged precipitation amount for the high and low resolution simulations are 1.7%/K-1 and 1.8%/K-1, respectively. The sensitivities for heavy, moderate, light and drizzle rain are 6.8, -1.2, 0.0, 0.2%/K-1 for low and 6.3, -1.5, 0.4, -0.2%/K -1 for high resolution simulations. The number of rainy days decreases in a warming scenario, by 3.4 and 4.2 day/year-1, respectively. The most sensitive response of 6.3-6.8%/K-1 for the heavy rain approaches that of the 7%/K-1 for the Clausius-Clapeyron scaling limit. During the twenty-first century simulation, the increases in precipitation are larger over high latitude and wet regions in low and mid-latitudes. Over the dry regions, such as the subtropics, the precipitation amount and frequency decrease. There is a higher occurrence of low and heavy rain from the tropics to mid-latitudes at the expense of the decreases in the frequency of moderate rain. In the third part, the inter-annual variability of the northern hemisphere storm tracks is examined. In the Athena simulations, the leading modes of the observed storm track variability are reproduced realistically by all runs. In general, the fluctuations of the model storm tracks in the North Pacific and Atlantic basins are largely independent of each other. Within each basin, the variations are characterized by the intensity change near the climatological center and the meridional shift of the storm track location. These two modes are associated with major teleconnection patterns of the low frequency atmospheric variations. These model results are not sensitive to resolution. Using the Minerva hindcast initialized in November, it is shown that a portion of the winter (December-January) storm track variability is predictable, mainly due to the influences of the atmospheric wave trains induced by the El Nino and Southern Oscillation.

Can We Untangle the Weather? Stable Water Isotope Controls on the Juneau Icefield

NASA Astrophysics Data System (ADS)

Ihle, A. C.; Keenan, E.; Yong, C.; Bridgers, S. L.; Markle, B. R.; Hamel, J.; Klein, E. S.

2017-12-01

Stable water isotopes in snow and ice provide a reliable proxy for past weather and climate. However, untangling weather and climate signals from water isotopes on the Juneau Icefield, Alaska, has proven difficult due to consistent summer melt and rain. The Juneau Icefield is a large glaciated region consisting of complex terrain and sharp climatic gradients. Here we study how topographic steepness and elevation influence stable water isotope ratios on the Juneau Icefield using vertical snowpit profiles collected from water year 2017's snowpack. As terrain steepens, we expect gradients in isotope ratios to intensify. In addition, we aim to determine how post-depositional metamorphism, particularly precipitation, affects water isotope ratios. We anticipate rain events to increase the proportion of heavy water isotopes. Lastly, we compare model output and remote sensing observations of storm origin to vertical stratigraphy of stable isotope ratios in the snowpack in order to determine if it is possible to use isotopes to identify past storm tracks on the Juneau Icefield. Snowpack isotope stratigraphy ratios can likely be linked to seasonal trends of storm characteristics. Given this enhanced understanding of how stable water isotopes behave on the Juneau Icefield, we contribute to the understanding of past weather and climate, both here and elsewhere, and explore the possibility for future deep ice cores on the Juneau Icefield.

Hurricane Matthew Hits Haiti

NASA Image and Video Library

2017-12-08

Read more from: go.nasa.gov/2duxEeZ On October 4, 2016, Hurricane Matthew made landfall on southwestern Haiti as a category-4 storm—the strongest storm to hit the Caribbean nation in more than 50 years. Just hours after landfall, the Moderate Resolution Imaging Spectroradiometer (MODIS) on NASA’s Terra satellite acquired this natural-color image. At the time, Matthew had top sustained winds of about 230 kilometers (145 miles) per hour. Earlier on October 4, temperature data collected by MODIS on NASA’s Aqua satellite revealed that the cloud tops around Matthew were very cold (at least -57° Celsius, or -70° Fahrenheit). Cold cloud tops are known to produce heavy rainfall. The National Hurricane Center called for 380 to 500 millimeters (15 to 20 inches) of rain in Southern Haiti and in the southwestern Dominican Republic. The northward movement of the storm should bring the center of Matthew over eastern Cuba late on October 4. Dangerous conditions can extend far beyond a storm’s center. According to National Hurricane Center forecasters, Matthew is “likely to produce devastating impacts from storm surge, extreme winds, heavy rains, flash floods, and/or mudslides in portions of the watch and warning areas in Haiti, Cuba, and the Bahamas.” NASA Earth Observatory image by Joshua Stevens, using MODIS data from the Land Atmosphere Near real-time Capability for EOS (LANCE). Caption by Kathryn Hansen.

The Aggregate Description of Semi-Arid Vegetation with Precipitation-Generated Soil Moisture Heterogeneity

NASA Technical Reports Server (NTRS)

White, Cary B.; Houser, Paul R.; Arain, Altaf M.; Yang, Zong-Liang; Syed, Kamran; Shuttleworth, W. James

1997-01-01

Meteorological measurements in the Walnut Gulch catchment in Arizona were used to synthesize a distributed, hourly-average time series of data across a 26.9 by 12.5 km area with a grid resolution of 480 m for a continuous 18-month period which included two seasons of monsoonal rainfall. Coupled surface-atmosphere model runs established the acceptability (for modelling purposes) of assuming uniformity in all meteorological variables other than rainfall. Rainfall was interpolated onto the grid from an array of 82 recording rain gauges. These meteorological data were used as forcing variables for an equivalent array of stand-alone Biosphere-Atmosphere Transfer Scheme (BATS) models to describe the evolution of soil moisture and surface energy fluxes in response to the prevalent, heterogeneous pattern of convective precipitation. The calculated area-average behaviour was compared with that given by a single aggregate BATS simulation forced with area-average meteorological data. Heterogeneous rainfall gives rise to significant but partly compensating differences in the transpiration and the intercepted rainfall components of total evaporation during rain storms. However, the calculated area-average surface energy fluxes given by the two simulations in rain-free conditions with strong heterogeneity in soil moisture were always close to identical, a result which is independent of whether default or site-specific vegetation and soil parameters were used. Because the spatial variability in soil moisture throughout the catchment has the same order of magnitude as the amount of rain failing in a typical convective storm (commonly 10% of the vegetation's root zone saturation) in a semi-arid environment, non-linearitv in the relationship between transpiration and the soil moisture available to the vegetation has limited influence on area-average surface fluxes.

TRMM precipitation analysis of extreme storms in South America: Bias and climatological contribution

NASA Astrophysics Data System (ADS)

Rasmussen, K. L.; Houze, R.; Zuluaga, M. D.; Choi, S. L.; Chaplin, M.

2013-12-01

The TRMM (Tropical Rainfall Measuring Mission) satellite was designed both to measure spatial and temporal variation of tropical rainfall around the globe and to understand the factors controlling the precipitation. TRMM observations have led to the realization that storms just east of the Andes in southeastern South America are among the most intense deep convection in the world. For a complete perspective of the impact of intense precipitation systems on the hydrologic cycle in South America, it is necessary to assess the contribution from various forms of extreme storms to the climatological rainfall. However, recent studies have suggested that the TRMM Precipitation Radar (PR) algorithm significantly underestimates surface rainfall in deep convection over land. Prior to investigating the climatological behavior, this research first investigates the range of the rain bias in storms containing four different types of extreme radar echoes: deep convective cores, deep and wide convective cores, wide convective cores, and broad stratiform regions over South America. The TRMM PR algorithm exhibits bias in all four extreme echo types considered here when the algorithm rates are compared to a range of conventional Z-R relations. Storms with deep convective cores, defined as high reflectivity echo volumes that extend above 10 km in altitude, show the greatest underestimation, and the bias is unrelated to their echo top height. The bias in wide convective cores, defined as high reflectivity echo volumes that extend horizontally over 1,000 km2, relates to the echo top, indicating that storms with significant mixed phase and ice hydrometeors are similarly affected by assumptions in the TRMM PR algorithm. The subtropical region tends to have more intense precipitating systems than the tropics, but the relationship between the TRMM PR rain bias and storm type is the same regardless of the climatological regime. The most extreme storms are typically not collocated with regions of high climatological precipitation. A quantitative approach that accounts for the previously described bias using TRMM PR data is employed to investigate the role of the most extreme precipitating systems on the hydrological cycle in South America. These data are first used to investigate the relative contribution of precipitation from the TRMM-identified echo cores to each separate storm in which the convective cores are embedded. The second part of the study assesses how much of the climatological rainfall in South America is accounted for by storms containing deep convective, wide convective, and broad stratiform echo components. Systems containing these echoes produce very different hydrologic responses. From a hydrologic and climatological viewpoint, this empirical knowledge is critical, as the type of runoff and flooding that may occur depends on the specific character of the convective storm and has broad implications for the hydrological cycle in this region.

Texas floods of 1940

USGS Publications Warehouse

Breeding, Seth D.

1948-01-01

Floods occurred in Texas during, June, July, and November 1940 that exceeded known stages on many small streams and at a few places on the larger streams. Stages at several stream-gaging stations exceeded the maximum known at those places since the collection of daily records began. A storm, haying its axis generally on a north-south line from Cameron to Victoria and extending across the Brazos, Colorado, Lavaca, and Guadalupe River Basins, caused heavy rainfall over a large part of south-central Texas. The maximum recorded rain of 22.7 inches for the 2-day period June 29-30 occurred at Engle. Of this amount, 17.5 inches fell in the 12-hour period between 8 p.m. June 29, and 8 a.m. June 30. Light rains fell at a number of places on June 28, and additional light rains fell at many places within the area from July 1 to 4. During the period June 28 to July 4 more than 20 inches of rain fell over an area of 300 square miles, more than 15 inches over 1,920 square miles, and more than 10 inches over 5,100 square miles. The average annual rainfall for the area experiencing the heaviest rainfall during this storm is about 35 inches. Farming is largely confined to the fertile flood plains in much of the area subjected to the record-breaking floods in June and July. Therefore these floods, coming at the height of the growing season, caused severe losses to crops. Much damage was done also to highways and railways. The city of Hallettsville suffered the greatest damage of any urban area. The Lavaca River at that place reached a stage 8 feet higher than ever known before, drowned several people, destroyed many homes, and submerged almost the entire business district. The maximum discharge there was 93,100 second-feet from a drainage area of 101 square miles. Dry Creek near Smithville produced a maximum discharge of 1,879 second-feet from an area of 1.48 square miles and a runoff of 11.3 inches in a 2-day period from a rainfall of 19.5 inches. The area in the Colorado River Basin between Smithville and La Grange, amounting to 550 square miles, had an average rainfall of 19.3 inches, of which 11.5 inches appeared as runoff. The maximum discharge at La Grange was 182,000 second-feet, with much the greater part coming from below Smithville. This is probably a record-breaking flood for the area between Smithville and La Grange, but stages as much as 16 feet higher have occurred at La Grange. Heavy rainfall over the east half of Texas November 21-26 caused large floods in all streams in Texas east of the Guadalupe River. The maximum recorded rainfall for the 2-day period November 24-25 was 20.46 inches at Hempstead, of which 16.00 inches fell in 24 hours or less. The storm occurred during the period November 20-26, with the greater part of the rain falling November 23-25. During the period November 20-26, rainfall in Texas amounted to more than 15 inches over an area of 3,380 square miles, and 'to more than 10 inches over an area of 17,570 square miles. The average annual rainfall for the area in Texas experiencing more than 10 inches of rain during this storm ranges from 501 inches on the east border of the State to 35 inches near the west edge of the area. The study of this storm for the purposes of this report is limited to the San Jacinto River Basin, which had an average rainfall of 13.6 inches. This basin has an area of 2,791 square miles above the gaging station near Huffman and is typical in topographic and hydrologic features of much of eastern Texas. The stage reached at the gage near Huffman was about 1 foot higher than known before, the maximum discharge was 253,000 second-feet, and the runoff from the storm amounted to 8.8 inches. The November flood came after crops had been harvested, and its damage was mainly the destruction of highways and railways and the drowning of livestock. The storage reservoirs on the Colorado River located well upstream from the storm areas herein studied had very little effect on

Stalling Tropical Cyclones over the Atlantic Basin

NASA Astrophysics Data System (ADS)

Nielsen-Gammon, J. W.; Emanuel, K.

2017-12-01

Hurricane Harvey produced massive amounts of rain over southeast Texas and southwest Louisiana. Average storm total rainfall amounts over a 10,000 square mile (26,000 square km) area exceeded 30 inches (750 mm). An important aspect of the storm that contributed to the large rainfall totals was its unusual motion. The storm stalled shortly after making landfall, then moved back offshore before once again making landfall five days later. This storm motion permitted heavy rainfall to occur in the same general area for an extended period of time. The unusual nature of this event motivates an investigation into the characteristics and potential climate change influences on stalled tropical cyclones in the Atlantic basin using the HURDAT 2 storm track database for 1866-2016 and downscaled tropical cyclones driven by simulations of present and future climate. The motion of cyclones is quantified as the size of a circle circumscribing all storm locations during a given length of time. For a three-day period, Harvey remained inside a circle with a radius of 123 km. This ranks within the top 0.6% of slowest-moving historical storm instances. Among the 2% of slowest-moving storm instances prior to Harvey, only 13 involved storms that stalled near the continental United States coast, where they may have produced substantial rainfall onshore while tapping into marine moisture. Only two such storms stalled in the month of September, in contrast to 20 September stalls out of the 36 storms that stalled over the nearby open Atlantic. Just four of the stalled coastal storms were hurricanes, implying a return frequency for such storms of much less than once per decade. The synoptic setting of these storms is examined for common features, and historical and projected trends in occurrences of stalled storms near the coast and farther offshore are investigated.

Analysis of warm convective rain events in Catalonia

NASA Astrophysics Data System (ADS)

Ballart, D.; Figuerola, F.; Aran, M.; Rigo, T.

2009-09-01

Between the end of September and November, events with high amounts of rainfall are quite common in Catalonia. The high sea surface temperature of the Mediterranean Sea near to the Catalan Coast is one of the most important factors that help to the development of this type of storms. Some of these events have particular characteristics: elevated rain rate during short time periods, not very deep convection and low lightning activity. Consequently, the use of remote sensing tools for the surveillance is quite useless or limited. With reference to the high rain efficiency, this is caused by internal mechanisms of the clouds, and also by the air mass where the precipitation structure is developed. As aforementioned, the contribution of the sea to the air mass is very relevant, not only by the increase of the big condensation nuclei, but also by high temperature of the low layers of the atmosphere, where are allowed clouds with 5 or 6 km of particles in liquid phase. In fact, the freezing level into these clouds can be detected by -15ºC. Due to these characteristics, this type of rainy structures can produce high quantities of rainfall in a relatively brief period of time, and, in the case to be quasi-stationary, precipitation values at surface could be very important. From the point of view of remote sensing tools, the cloud nature implies that the different tools and methodologies commonly used for the analysis of heavy rain events are not useful. This is caused by the following features: lightning are rarely observed, the top temperatures of clouds are not cold enough to be enhanced in the satellite imagery, and, finally, reflectivity radar values are lower than other heavy rain cases. The third point to take into account is the vulnerability of the affected areas. An elevated percentage of the Catalan population lives in the coastal region. In the central coast of Catalonia, the urban areas are surrounded by a not very high mountain range with small basins and steep slopes. These factors increase the number of flash floods and the risk indexes. In the present study it is showed the general characteristics of the warm rain events observed in Catalonia, using meteorological, pluviometric, thermodynamic, and remote sensing data. Beside this, other heavy rain events with different features have been analyzed with the purpose of identify the main differences and to improve the knowledge in order to provide enough information for surveillance tasks

Introducing stochastics into the simulation of convective precipitation events

NASA Astrophysics Data System (ADS)

Pistotnik, Georg

2010-05-01

In a joint project, the Central Institute for Meteorology and Geodynamics (ZAMG) and the Vienna University of Technology aimed to characterize strong precipitation events and their impact in the Bucklige Welt region in Eastern Austria. Both the region's hydrological and meteorological characteristics, namely its composition of virtually countless small catchments with short response times and a high frequency of summertime convective storms, cause the occurrence of flooding to be strictly tied to convective rainfall events, which is why this study has been focused on this type of precipitation. The meteorological database consists of the ZAMG's high-resolution analysis and nowcasting system INCA ("Integrated Nowcasting through Comprehensive Analysis"), which provides a set of precipitation analyses generated by a statistically optimized combination of rain gauge measurements and radar data with a temporal resolution of 15 minutes and a spatial resolution of 1 kilometre. An intensity threshold of 3.8mm/15min has been used to classify any observed precipitation as a convective one, thus extracting 245 convection days with a total number of almost 1600 individual storm events over the project region out of the 5-year data set from 2003 to 2007. Consecutive analyses were used to compute the motion of these storms, a complex process that could not be completely automatized; due to the repeated occurrence of storm splits or coalescences, a manual control of the automatically provided "suggestion" of movement had to be performed in order to merge two or more precipitation maxima to a single storm if necessary, thus yielding the smoothest and most plausible storm tracks and ensuring a high quality of the database. In the first part of the project, distributions for all characteristic parameters have been derived, including the number of storms per day, their place and time of initiation, their motion, lifetime, maximum intensity and maximum "cell volume" (i.e. overall precipitation per time step). Both components of the mean motion as well as of its deviations could be approximated by normal distributions, whereas the number of storms per day, their lifetime, maximum intensity and maximum cell volume roughly followed exponential distributions. The shapes of the convective cells were approximated by Gaussian bells with the peak intensity and the cell volume as boundary conditions. The temporal courses of the peak intensities and cell volumes were assumed to follow parabolas which are symmetric with respect to the half of the lifetime. In the second part of the project, these distributions were used to drive a random generator that allows simulating an arbitrary number of convection days in order to obtain pseudo time series of convective precipitation for each grid point. An algorithm to create correlated samples of random numbers enabled to also account for the observed correlation between some of the parameters, i.e. lifetime and maximum intensity or maximum cell volume. The spatial structures of the return periods of simulated convective precipitation events may provide valuable additional information when being assimilated to the time series measured by the (unfortunately rather sparse) rain gauges in this region. Thus, further studies have to investigate to what extent the "convection simulator" is able to reproduce these time series. Some iterative fine-tuning of the parameters' distributions as well as an extension of the database to a longer time span may further improve the results and enable to simulate realistic spatio-temporal convection scenarios ("design storms") that have the potential to feed hydrological models and, together with vegetation and soil characteristics, hopefully enable to better assess and regionalize the torrent hazard over the project region.

Drop Size Distribution Measurements Supporting the NASA Global Precipitation Measurement Mission: Infrastructure and Preliminary Results

NASA Technical Reports Server (NTRS)

Petersen, Walter A.; Carey, Lawerence D.; Gatlin, Patrick N.; Wingo, Matthew; Tokay, Ali; Wolff, David B.; Bringi, V. N.

2011-01-01

Global Precipitation Measurement Mission (GPM) retrieval algorithm validation requires datasets that characterize the 4-D structure, variability, and correlation properties of hydrometeor particle size distributions (PSD) and accumulations over satellite fields of view (5 -- 50 km). Key to this process is the combined use of disdrometer and polarimetric radar platforms. Here the disdrometer measurements serve as a reference for up-scaling dual-polarimetric radar observations of the PSD to the much larger volumetric sampling domain of the radar. The PSD observations thus derived provide a much larger data set for assessing DSD variability, and satellite-based precipitation retrieval algorithm assumptions, in all three spatial dimensions for a range of storm types and seasons. As one component of this effort, the GPM Ground Validation program recently acquired five 3rd generation 2D Video disdrometers as part of its Disdrometer and Radar Observations of Precipitation Facility (DROP), currently hosted in northern Alabama by the NASA Marshall Space Flight Center and the University of Alabama in Huntsville. These next-generation 2DVDs were operated and evaluated in different phases of data collection under the scanning domain of the UAH ARMOR C-band dual-polarimetric radar. During this period approximately 7500 minutes of PSD data were collected and processed to create gamma size distribution parameters using a truncated method of moments approach. After creating the gamma parameter datasets the DSDs were then used as input to T-matrix code for computation of polarimetric radar moments at C-band. The combined dataset was then analyzed with two basic objectives in mind: 1) the investigation of seasonal variability in the rain PSD parameters as observed by the 2DVDs; 2) the use of combined polarimetric moments and observed gamma distribution parameters in a functional form to retrieve PSD parameters in 4-D using the ARMOR radar for precipitation occurring in different seasons and for different rain system types. Preliminary results suggest that seasonal variations in the DSD parameters do occur, but are most pronounced when comparing tropical PSDs to either winter or summer convective precipitation. For example the previously documented shift to relatively smaller drop diameters in higher number concentrations for equivalent rain rate bins was observed in tropical storm rainbands occurring over Huntsville. On a more inter seasonal basis empirical fits between parameters such as D0 and ZDR do not appear to exhibit robust seasonal biases- i.e., one fit seems to work for all seasons within acceptable standard error (O[10%]) for estimates of D0. In polarimetric retrievals of the vertical variability in PSD (rain layer) for a tropical rainband we find that the Do varies with height when partitioned by specified precipitation categories (e.g., convective or stratiform, heavy and light stratiform etc.) but this variation is of order 10-20% and is smaller than the difference in D0 observed between the basic delineation of convective and stratiform precipitation types. Currently we are expanding our analysis of the vertical structure of the PSD to include several seasonally and/or dynamically-different storm system types (e.g., winter convection and stratiform events; summer mid-latitude convective etc.) sampled by ARMOR. The study will present the results of our combined analyses.

76 FR 66629 - Establishment of the Pine Mountain-Cloverdale Peak Viticultural Area

Federal Register 2010, 2011, 2012, 2013, 2014

2011-10-27

... explains. The petition states that local growers report that Pine Mountain vineyards are naturally free of.... Southern storms often stall over Pine Mountain and the Mayacmas range, dropping more rain than in other..., and very well to excessively well-drained. Also, these mountain soils include large amounts of sand...

KSC-01pp1364

NASA Image and Video Library

2001-07-19

KENNEDY SPACE CENTER, Fla. -- As night approaches, the P5 truss rolls away from the Spaceport Florida hangar where it waited out a rain storm. The truss is being transported to the Space Station Processing Facility. The P5 is scheduled for delivery to the International Space Station on mission 12A.1 in April 2003

20. Photocopied August 1978. CANAL SECTION III, LOOKING SOUTH, AUGUST ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

20. Photocopied August 1978. CANAL SECTION III, LOOKING SOUTH, AUGUST OR SEPTEMBER 1900, FOLLOWING A MAJOR BANK SLIDE. SLIDES LIKE THIS ONE WERE FAIRLY FREQUENT FOLLOWING RAIN STORMS BEFORE THE CANAL WALLS WERE TIMBER LINED IN THE EARTH SECTIONS. (64) - Michigan Lake Superior Power Company, Portage Street, Sault Ste. Marie, Chippewa County, MI

Dynamic gauge adjustment of high-resolution X-band radar data for convective rain storms: Model-based evaluation against measured combined sewer overflow

NASA Astrophysics Data System (ADS)

Borup, Morten; Grum, Morten; Linde, Jens Jørgen; Mikkelsen, Peter Steen

2016-08-01

Numerous studies have shown that radar rainfall estimates need to be adjusted against rain gauge measurements in order to be useful for hydrological modelling. In the current study we investigate if adjustment can improve radar rainfall estimates to the point where they can be used for modelling overflows from urban drainage systems, and we furthermore investigate the importance of the aggregation period of the adjustment scheme. This is done by continuously adjusting X-band radar data based on the previous 5-30 min of rain data recorded by multiple rain gauges and propagating the rainfall estimates through a hydraulic urban drainage model. The model is built entirely from physical data, without any calibration, to avoid bias towards any specific type of rainfall estimate. The performance is assessed by comparing measured and modelled water levels at a weir downstream of a highly impermeable, well defined, 64 ha urban catchment, for nine overflow generating rain events. The dynamically adjusted radar data perform best when the aggregation period is as small as 10-20 min, in which case it performs much better than static adjusted radar data and data from rain gauges situated 2-3 km away.

Satellite Views Early Thanksgiving Travel Trouble Areas in U.S.

NASA Image and Video Library

2017-12-08

This NOAA's GOES satellite infrared image taken on Nov. 25 at 11:45 UTC (6:45 a.m. EST) shows two main weather systems over the U.S. Credit: NASA/NOAA GOES Project As the U.S. Thanksgiving holiday approaches this Thursday, November 27, NOAA's GOES-East and GOES-West satellites are keeping a weather eye out for storms that may affect early travelers. In an image from Nov. 25, the satellites show an active weather pattern is in place for travelers across the central and eastern U.S. NOAA's GOES-East satellite provides visible and infrared images over the eastern U.S. and the Atlantic Ocean, while NOAA's GOES-West satellite covers the western U.S. and Pacific Ocean from its fixed orbit in space. Data from both satellites were combined at NASA's GOES Project to create a full view of the U.S. on Nov. 25 at 11:45 UTC (6:45 a.m. EST). The image shows clouds associated with cold front stretching from the Gulf of Mexico over northern Florida and along the U.S. East coast to eastern Canada. Clouds associated with another area of low pressure are in the northern Rockies and northwestern U.S. To create the image, NASA/NOAA's GOES Project takes the cloud data from NOAA's GOES-East satellite and overlays it on a true-color image of land and ocean created by data from the Moderate Resolution Imaging Spectroradiometer, or MODIS, instrument that flies aboard NASA's Aqua and Terra satellites. Together, those data created the entire picture of the storm and show its movement. After the storm system passes, the snow on the ground becomes visible. NOAA's National Weather Service Weather Prediction Center said "a storm system will develop off the coast of the Carolinas early Wednesday (Nov. 25) and strengthen as it moves rapidly up the East Coast Wednesday into early Thursday (Nov. 26). Heavy snow is likely to begin in the central Appalachians early Wednesday morning, spreading northeast through the interior Mid-Atlantic into New England by Wednesday night. Winter Storm Watches are in effect for these areas." For travelers in the western U.S., the Northern Rocky Mountains are expected to receive more snow from the north side of a stationary frontal boundary. South of the boundary rain showers will affect the lower valley. The National Weather Service calls for cold weather to continue in the northern Plains and Upper Midwest as a Canadian surface high pressure rules the weather. The U.S. Southwest will experience nice weather for mid-week. In the Pacific Northwest, the National Weather Service noted that a warm front will bring rain, heavy at times, to the Cascades today and tonight. There will be a break in the heavier rains on Wednesday, then another period of heavy rain for the Cascades Wednesday night through Friday morning as a cold front slowly drags through the area. NOAA's GOES satellites provide the kind of continuous monitoring necessary for intensive data analysis. Geostationary describes an orbit in which a satellite is always in the same position with respect to the rotating Earth. This allows GOES to hover continuously over one position on Earth's surface, appearing stationary. As a result, GOES provide a constant vigil for the atmospheric triggers for severe weather conditions such as tornadoes, flash floods, hail storms and hurricanes.

Radar Observation of Large Attenuation in Convective Storms: Implications for the Dropsize Distribution

NASA Technical Reports Server (NTRS)

Tian, Lin; Heymsfield, G. M.; Srivastava, R. C.

2000-01-01

Airborne meteorological radars typically operate at attenuating wavelengths. The path integrated attenuation (PIA) can be estimated using the surface reference technique (SRT). In this method, an initial value is determined for the radar cross section of the earth surface in a rain-free area in relatively close proximity to the rain cloud. During subsequent observations of precipitation any decrease 'in the observed surface cross section from the reference value s assumed to be a result of the two-way attenuation along the propagation path. In this paper we present selected instances of high PIA observed over land by an airborne radar. The observations were taken in Brazil and Florida during TRMM (Tropical Rainfall Measurement Mission) field campaigns. We compared these observations with collocated and nearly simultaneous ground-based radar observations by an S-band radar that is not subject to significant attenuation. In this preliminary evaluation, a systematic difference in the attenuation in the two storms is attributed to a difference in the raindrop size distributions; this is supported by observations of ZDR (differential reflectivity).

Soil slip/debris flow localized by site attributes and wind-driven rain in the San Francisco Bay region storm of January 1982

USGS Publications Warehouse

Pike, R.J.; Sobieszczyk, S.

2008-01-01

GIS analysis at 30-m resolution reveals that effectiveness of slope-destabilizing processes in the San Francisco Bay area varies with compass direction. Nearly half the soil slip/debris flows mapped after the catastrophic rainstorm of 3-5 January 1982 occurred on slopes that face S to WSW, whereas fewer than one-quarter have a northerly aspect. Azimuthal analysis of hillside properties for susceptible terrain near the city of Oakland suggests that the skewed aspect of these landslides primarily reflects vegetation type, ridge and valley alignment, and storm-wind direction. Bedrock geology, soil expansivity, and terrain height and gradient also were influential but less so; the role of surface curvature is not wholly resolved. Normalising soil-slip aspect by that of the region's NNW-striking topography shifts the modal azimuth of soil-slip aspect from SW to SE, the direction of origin of winds during the 1982 storm-but opposite that of the prevailing WNW winds. Wind from a constant direction increases rainfall on windward slopes while diminishing it on leeward slopes, generating a modelled difference in hydrologically effective rainfall of up to 2:1 on steep hillsides in the Oakland area. This contrast is consistent with numerical simulations of wind-driven rain and with rainfall thresholds for debris-flow activity. We conclude that storm winds from the SE in January 1982 raised the vulnerability of the Bay region's many S-facing hillsides, most of which are covered in shallow-rooted shrub and grass that offer minimal resistance to soil slip. Wind-driven rainfall also appears to have controlled debris-flow location in a major 1998 storm and probably others. Incorporating this overlooked influence into GIS models of debris-flow likelihood would improve predictions of the hazard in central California and elsewhere.

A Process-Based Insight into the Severity of 'Super' Storm Desmond

NASA Astrophysics Data System (ADS)

Matthews, Tom; Murphy, Conor; Gerard, McCarthy; Rob, Wilby

2017-04-01

Climate warming is projected to increase winter rainfall and societally-impactful flood frequency across the British-Irish Isles (BI). The dynamical explanation for this change is linked to the North Atlantic (NA) storm track, with projections indicating both an enhanced frequency of wintertime extratropical cyclones ('cyclones'), and an increase in their average precipitation. The latter is, in part, a result of more intense moisture transport in cyclones' warm sectors by 'Atmospheric Rivers' (ARs), thermodynamically-driven by enhanced absolute humidity consistent with the Clausius-Clapeyron relation. It is against this backdrop that we scrutinise the physical drivers of the record-breaking rain and flood event associated with 'Storm Desmond' in December, 2015. We find that more than 3,500 km2 experienced rainfall in excess of the mean annual maximum during the storm's passage. The exceptional rain amounts were due to an AR more intense than any other in our observational record (1979-2015). However, we find that its unparalleled strength was as much a consequence of strong wind speeds as high humidity, so its severity cannot be attributed so simply to climate warming. This position is made clearer through a Lagrangian air mass tracking procedure, where we show that most (67%) of the moisture that precipitated out over BI during Desmond's passage evaporated from sea surfaces that were cooler than their 1951-1980 average. We therefore conclude that 1) the process-based observational approach applied here can provide valuable insight into climate change attribution assessments; and 2) Storm Desmond - despite being the most severe on record - was perhaps moderated by the anomalously cool NA sea-surface temperatures, which may have suppressed evaporation and vapour transport. The capacity for an even more impactful AR should SSTs in the sub-polar NA return to even their 20th Century averages, given otherwise identical synoptic circulation, should therefore be appreciated by planners and policy makers alike.

Flood of May 26-27, 1984 in Tulsa, Oklahoma

USGS Publications Warehouse

Bergman, DeRoy L.; Tortorelli, Robert L.

1988-01-01

The greatest flood disaster in the history of Tulsa, Oklahoma occurred during 8 hours from 2030 hours May 26 to 0430 hours May 27, 1984, as a result of intense rainfall centered over the metropolitan area. Storms of the magnitude that caused this flood are not uncommon to the southern great plains. Such storms are seldom documented in large urban areas. Total rainfall depth and rainfall distribution in the Tulsa metropolitan area during the May 26-27 storm were recorded by 16 recording rain gages. This report presents location of recording rain gages with corresponding rainfall histograms and mass curves, lines of equal rainfall depth (map A), and flood magnitudes and inundated areas of selected streams within the city (map B). The limits of the study areas (fig. 1) are the corporate boundaries of Tulsa, an area of about 185 square miles. Streams draining the city are: Dirty Butter, Coal, and Mingo Creeks which drain northward into Bird Creek along the northern boundary of the city; and Cherry, Crow, Harlow, Joe Haikey, Fry, Vensel, Fred, and Mooser Creeks which flow into the Arkansas River along the southern part of the city. Flooding along Haikey, Fry, Fred, Vensel, and Mooser Creeks was not documented for this report. The Arkansas River is regulated by Keystone Dam upstream from Tulsa (fig. 1). The Arkansas River remained below flood stage during the storm. Flooded areas in Tulsa (map B) were delineated on the topographic maps using flood profiles based on surveys of high-water marks identified immediately after the flood. The flood boundaries show the limits of stream flooding. Additional areas flooded because of overfilled storm drains or by sheet runoff are not shown in this report. Data presented in this report, including rainfall duration and frequency, and flood discharges and elevations, provide city officials and consultants a technical basis for making flood-plain management decisions.

Flood Losses Associated with Winter Storms in the U.S. Northeast

NASA Astrophysics Data System (ADS)

Ting, M.; Shimkus, C.

2015-12-01

Winter storms pose a number of hazards to coastal communities in the U.S. Northeast including heavy rain, snow, strong wind, cold temperatures, and flooding. These hazards can cause millions in property damages from one storm alone. This study addresses the impacts of winter storms from 2001 - 2012 on coastal counties in the U.S. Northeast and underscores the significant economic consequences extreme winter storms have on property. The analysis on the types of hazards (floods, strong wind, snow, etc.) and associated damage from the National Climatic Data Center Storm Events Database indicates that floods were responsible for the highest damages. This finding suggests that winter storm vulnerability could grow in the future as precipitation intensity increases and sea level rise exacerbate flood losses. Flood loss maps are constructed based on damage amount, which can be compared to the flood exposure maps constructed by the NOAA Office of Coastal Management. Interesting agreements and discrepancies exist between the two methods, which warrant further examination. Furthermore, flood losses often came from storms characterized as heavy precipitation storms and strong surge storms, and sometimes both, illustrating the compounding effect of flood risks in the region. While New Jersey counties experienced the most damage per unit area, there is no discernable connection between population density and damage amount, which suggests that societal impacts may rely less on population characteristics and more on infrastructure types and property values, which vary throughout the region.

Impacts on the deep-sea ecosystem by a severe coastal storm.

PubMed

Sanchez-Vidal, Anna; Canals, Miquel; Calafat, Antoni M; Lastras, Galderic; Pedrosa-Pàmies, Rut; Menéndez, Melisa; Medina, Raúl; Company, Joan B; Hereu, Bernat; Romero, Javier; Alcoverro, Teresa

2012-01-01

Major coastal storms, associated with strong winds, high waves and intensified currents, and occasionally with heavy rains and flash floods, are mostly known because of the serious damage they can cause along the shoreline and the threats they pose to navigation. However, there is a profound lack of knowledge on the deep-sea impacts of severe coastal storms. Concurrent measurements of key parameters along the coast and in the deep-sea are extremely rare. Here we present a unique data set showing how one of the most extreme coastal storms of the last decades lashing the Western Mediterranean Sea rapidly impacted the deep-sea ecosystem. The storm peaked the 26(th) of December 2008 leading to the remobilization of a shallow-water reservoir of marine organic carbon associated with fine particles and resulting in its redistribution across the deep basin. The storm also initiated the movement of large amounts of coarse shelf sediment, which abraded and buried benthic communities. Our findings demonstrate, first, that severe coastal storms are highly efficient in transporting organic carbon from shallow water to deep water, thus contributing to its sequestration and, second, that natural, intermittent atmospheric drivers sensitive to global climate change have the potential to tremendously impact the largest and least known ecosystem on Earth, the deep-sea ecosystem.

Impacts on the Deep-Sea Ecosystem by a Severe Coastal Storm

PubMed Central

Sanchez-Vidal, Anna; Canals, Miquel; Calafat, Antoni M.; Lastras, Galderic; Pedrosa-Pàmies, Rut; Menéndez, Melisa; Medina, Raúl; Company, Joan B.; Hereu, Bernat; Romero, Javier; Alcoverro, Teresa

2012-01-01

Major coastal storms, associated with strong winds, high waves and intensified currents, and occasionally with heavy rains and flash floods, are mostly known because of the serious damage they can cause along the shoreline and the threats they pose to navigation. However, there is a profound lack of knowledge on the deep-sea impacts of severe coastal storms. Concurrent measurements of key parameters along the coast and in the deep-sea are extremely rare. Here we present a unique data set showing how one of the most extreme coastal storms of the last decades lashing the Western Mediterranean Sea rapidly impacted the deep-sea ecosystem. The storm peaked the 26th of December 2008 leading to the remobilization of a shallow-water reservoir of marine organic carbon associated with fine particles and resulting in its redistribution across the deep basin. The storm also initiated the movement of large amounts of coarse shelf sediment, which abraded and buried benthic communities. Our findings demonstrate, first, that severe coastal storms are highly efficient in transporting organic carbon from shallow water to deep water, thus contributing to its sequestration and, second, that natural, intermittent atmospheric drivers sensitive to global climate change have the potential to tremendously impact the largest and least known ecosystem on Earth, the deep-sea ecosystem. PMID:22295084

Frequency of extreme Sahelian storms tripled since 1982 in satellite observations.

PubMed

Taylor, Christopher M; Belušić, Danijel; Guichard, Françoise; Parker, Douglas J; Vischel, Théo; Bock, Olivier; Harris, Phil P; Janicot, Serge; Klein, Cornelia; Panthou, Gérémy

2017-04-26

The hydrological cycle is expected to intensify under global warming, with studies reporting more frequent extreme rain events in many regions of the world, and predicting increases in future flood frequency. Such early, predominantly mid-latitude observations are essential because of shortcomings within climate models in their depiction of convective rainfall. A globally important group of intense storms-mesoscale convective systems (MCSs)-poses a particular challenge, because they organize dynamically on spatial scales that cannot be resolved by conventional climate models. Here, we use 35 years of satellite observations from the West African Sahel to reveal a persistent increase in the frequency of the most intense MCSs. Sahelian storms are some of the most powerful on the planet, and rain gauges in this region have recorded a rise in 'extreme' daily rainfall totals. We find that intense MCS frequency is only weakly related to the multidecadal recovery of Sahel annual rainfall, but is highly correlated with global land temperatures. Analysis of trends across Africa reveals that MCS intensification is limited to a narrow band south of the Sahara desert. During this period, wet-season Sahelian temperatures have not risen, ruling out the possibility that rainfall has intensified in response to locally warmer conditions. On the other hand, the meridional temperature gradient spanning the Sahel has increased in recent decades, consistent with anthropogenic forcing driving enhanced Saharan warming. We argue that Saharan warming intensifies convection within Sahelian MCSs through increased wind shear and changes to the Saharan air layer. The meridional gradient is projected to strengthen throughout the twenty-first century, suggesting that the Sahel will experience particularly marked increases in extreme rain. The remarkably rapid intensification of Sahelian MCSs since the 1980s sheds new light on the response of organized tropical convection to global warming, and challenges conventional projections made by general circulation models.

Impacts of Synoptic Weather Patterns on Snow Albedo at Sites in New England

NASA Astrophysics Data System (ADS)

Adolph, A. C.; Albert, M. R.; Lazarcik, J.; Dibb, J. E.; Amante, J.; Price, A. N.

2015-12-01

Winter snow in the northeastern United States has changed over the last several decades, resulting in shallower snow packs, fewer days of snow cover and increasing precipitation falling as rain in the winter. In addition to these changes which cause reductions in surface albedo, increasing winter temperatures also lead to more rapid snow grain growth, resulting in decreased snow reflectivity. We present in-situ measurements and analyses to test the sensitivity of seasonal snow albedo to varying weather conditions at sites in New England. In particular, we investigate the impact of temperature on snow albedo through melt and grain growth, the impact of precipitation event frequency on albedo through snow "freshening," and the impact of storm path on snow structure and snow albedo. Over three winter seasons between 2013 and 2015, in-situ snow characterization measurements were made at three non-forested sites across New Hampshire. These near-daily measurements include spectrally resolved albedo, snow optical grain size determined through contact spectroscopy, snow depth, snow density and local meteorological parameters. Combining this information with storm tracks derived from HYSPLIT modeling, we quantify the current sensitivity of northeastern US snow albedo to temperature as well as precipitation type, frequency and path. Our analysis shows that southerly winter storms result in snow with a significantly lower albedo than storms which come from across the continental US or the Atlantic Ocean. Interannual variability in temperature and statewide spatial variability in snowfall rates at our sites show the relative importance of snowfall amount and temperatures in albedo evolution over the course of the winter.

Classification of Snowfall Events and Their Effect on Canopy Interception Efficiency in a Temperate Montane Forest.

NASA Astrophysics Data System (ADS)

Roth, T. R.; Nolin, A. W.

2015-12-01

Forest canopies intercept as much as 60% of snowfall in maritime environments, while processes of sublimation and melt can reduce the amount of snow transferred from the canopy to the ground. This research examines canopy interception efficiency (CIE) as a function of forest and event-scale snowfall characteristics. We use a 4-year dataset of continuous meteorological measurements and monthly snow surveys from the Forest Elevation Snow Transect (ForEST) network that has forested and open sites at three elevations spanning the rain-snow transition zone to the upper seasonal snow zone. Over 150 individual storms were classified by forest and storm type characteristics (e.g. forest density, vegetation type, air temperature, snowfall amount, storm duration, wind speed, and storm direction). The between-site comparisons showed that, as expected, CIE was highest for the lower elevation (warmer) sites with higher forest density compared with the higher elevation sites where storm temperatures were colder, trees were smaller and forests were less dense. Within-site comparisons based on storm type show that this classification system can be used to predict CIE.Our results suggest that the coupling of forest type and storm type information can improve estimates of canopy interception. Understanding the effects of temperature and storm type in temperate montane forests is also valuable for future estimates of canopy interception under a warming climate.

Floods of January-February 1963 in California and Nevada

USGS Publications Warehouse

Rantz, S.E.; Harris, E.E.

1963-01-01

Widespread flooding occurred in central California and northwestern Nevada during January 31 - February 1, 1963, as a result of intense precipitation of about 72 hours duration. The flood-producing storm was of the warm type, with precipitation falling as rain at altitudes as high as 8,000 feet. The heavy precipitation, totaling as much as 20 inches or more in the Sierra Nevada, fell on frozen ground or on the sparse snowpack that existed in the higher altitudes. The response of runoff to rainfall was dramatic, as streams throughout the area rose rapidly. Hardest hit were the basins of the American, Yuba, and Truckee Rivers, where flood peaks either reached record-breaking heights or rivalled the discharges attained in the memorable floods of November 1950 and December 1955. Because of the relatively short duration of the storm, the volume of flood flow in 1963 was not outstanding. Ten deaths were attributed to the storm or flood. Preliminary estimates indicate damage in excess of $16 million in foothill and valley areas, but no attempt has yet been made to assess the heavy damage to highways and drainage structures in the mountain areas. The U. S. Army, Corps of Engineirs estimates that its operation of flood-control facilities prevented additional damage of $236 million. Other reservoirs, operated primarily for water conservation or power production, were also instrumental in preventing damage.

Advanced Microwave Precipitation Radiometer (AMPR) for remote observation of precipitation

NASA Technical Reports Server (NTRS)

Galliano, J. A.; Platt, R. H.

1990-01-01

The design, development, and tests of the Advanced Microwave Precipitation Radiometer (AMPR) operating in the 10 to 85 GHz range specifically for precipitation retrieval and mesoscale storm system studies from a high altitude aircraft platform (i.e., ER-2) are described. The primary goals of AMPR are the exploitation of the scattering signal of precipitation at frequencies near 10, 19, 37, and 85 GHz together to unambiguously retrieve precipitation and storm structure and intensity information in support of proposed and planned space sensors in geostationary and low earth orbit, as well as storm-related field experiments. The development of AMPR will have an important impact on the interpretation of microwave radiances for rain retrievals over both land and ocean for the following reasons: (1) A scanning instrument, such as AMPR, will allow the unambiguous detection and analysis of features in two dimensional space, allowing an improved interpretation of signals in terms of cloud features, and microphysical and radiative processes; (2) AMPR will offer more accurate comparisons with ground-based radar data by feature matching since the navigation of the ER-2 platform can be expected to drift 3 to 4 km per hour of flight time; and (3) AMPR will allow underflights of the SSM/I satellite instrument with enough spatial coverage at the same frequencies to make meaningful comparisons of the data for precipitation studies.

Rainy Day: A Remote Sensing-Driven Extreme Rainfall Simulation Approach for Hazard Assessment

NASA Astrophysics Data System (ADS)

Wright, Daniel; Yatheendradas, Soni; Peters-Lidard, Christa; Kirschbaum, Dalia; Ayalew, Tibebu; Mantilla, Ricardo; Krajewski, Witold

2015-04-01

Progress on the assessment of rainfall-driven hazards such as floods and landslides has been hampered by the challenge of characterizing the frequency, intensity, and structure of extreme rainfall at the watershed or hillslope scale. Conventional approaches rely on simplifying assumptions and are strongly dependent on the location, the availability of long-term rain gage measurements, and the subjectivity of the analyst. Regional and global-scale rainfall remote sensing products provide an alternative, but are limited by relatively short (~15-year) observational records. To overcome this, we have coupled these remote sensing products with a space-time resampling framework known as stochastic storm transposition (SST). SST "lengthens" the rainfall record by resampling from a catalog of observed storms from a user-defined region, effectively recreating the regional extreme rainfall hydroclimate. This coupling has been codified in Rainy Day, a Python-based platform for quickly generating large numbers of probabilistic extreme rainfall "scenarios" at any point on the globe. Rainy Day is readily compatible with any gridded rainfall dataset. The user can optionally incorporate regional rain gage or weather radar measurements for bias correction using the Precipitation Uncertainties for Satellite Hydrology (PUSH) framework. Results from Rainy Day using the CMORPH satellite precipitation product are compared with local observations in two examples. The first example is peak discharge estimation in a medium-sized (~4000 square km) watershed in the central United States performed using CUENCAS, a parsimonious physically-based distributed hydrologic model. The second example is rainfall frequency analysis for Saint Lucia, a small volcanic island in the eastern Caribbean that is prone to landslides and flash floods. The distinct rainfall hydroclimates of the two example sites illustrate the flexibility of the approach and its usefulness for hazard analysis in data-poor regions.

Towards the Consideration of Surface and Environment variables for a Microwave Precipitation Algorithm Over Land

NASA Astrophysics Data System (ADS)

Wang, N. Y.; You, Y.; Ferraro, R. R.; Guch, I.

2014-12-01

Microwave satellite remote sensing of precipitation over land is a challenging problem due to the highly variable land surface emissivity, which, if not properly accounted for, can be much greater than the precipitation signal itself, especially in light rain/snow conditions. Additionally, surfaces such as arid land, deserts and snow cover have brightness temperatures characteristics similar to precipitation Ongoing work by NASA's GPM microwave radiometer team is constructing databases for the GPROF algorithm through a variety of means, however, there is much uncertainty as to what is the optimal information needed for the wide array of sensors in the GPM constellation, including examination of regional conditions. The at-launch database focuses on stratification by emissivity class, surface temperature and total precipitable water (TPW). We'll perform sensitivity studies to determine the potential role of environmental factors such as land surface temperature, surface elevation, and relative humidity and storm morphology such as storm vertical structure, height, and ice thickness to improve precipitation estimation over land, including rain and snow. In other words, what information outside of the satellite radiances can help describe the background and subsequent departures from it that are active precipitating regions? It is likely that this information will be a function of the various precipitation regimes. Statistical methods such as Principal Component Analysis (PCA) will be utilized in this task. Databases from a variety of sources are being constructed. They include existing satellite microwave measurements of precipitating and non-precipitating conditions, ground radar precipitation rate estimates, surface emissivity climatology from satellites, surface temperature and TPW from NWP reanalysis. Results from the analysis of these databases with respect to the microwave precipitation sensitivity to the variety of environmental conditions in different climate regimes will be discussed.

More frequent intense and long-lived storms dominate the springtime trend in central US rainfall

PubMed Central

Feng, Zhe; Leung, L. Ruby; Hagos, Samson; Houze, Robert A.; Burleyson, Casey D.; Balaguru, Karthik

2016-01-01

The changes in extreme rainfall associated with a warming climate have drawn significant attention in recent years. Mounting evidence shows that sub-daily convective rainfall extremes are increasing faster than the rate of change in the atmospheric precipitable water capacity with a warming climate. However, the response of extreme precipitation depends on the type of storm supported by the meteorological environment. Here using long-term satellite, surface radar and rain-gauge network data and atmospheric reanalyses, we show that the observed increases in springtime total and extreme rainfall in the central United States are dominated by mesoscale convective systems (MCSs), the largest type of convective storm, with increased frequency and intensity of long-lasting MCSs. A strengthening of the southerly low-level jet and its associated moisture transport in the Central/Northern Great Plains, in the overall climatology and particularly on days with long-lasting MCSs, accounts for the changes in the precipitation produced by these storms. PMID:27834368

More frequent intense and long-lived storms dominate the springtime trend in central US rainfall

DOE PAGES

Feng, Zhe; Leung, L. Ruby; Hagos, Samson M.; ...

2016-11-11

Here, the changes in extreme rainfall associated with a warming climate have drawn significant attention in recent years. Mounting evidence shows that sub-daily convective rainfall extremes are increasing faster than the rate of change in the atmospheric precipitable water capacity with a warming climate. However, the response of extreme precipitation depends on the type of storm supported by the meteorological environment. Here using long-term satellite, surface radar and rain-gauge network data and atmospheric reanalyses, we show that the observed increases in springtime total and extreme rainfall in 36 the central U.S. are dominated by mesoscale convective systems (MCSs), the largestmore » type of convective storm, with increased frequency and intensity of long-lasting MCSs. A strengthening of the southerly low-level jet and its associated moisture transport in the Central/Northern Great Plains, in the overall climatology and particularly on days with long-lasting MCSs, accounts for the changes in the precipitation produced by these storms.« less

More frequent intense and long-lived storms dominate the springtime trend in central US rainfall

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

Feng, Zhe; Leung, L. Ruby; Hagos, Samson M.

Here, the changes in extreme rainfall associated with a warming climate have drawn significant attention in recent years. Mounting evidence shows that sub-daily convective rainfall extremes are increasing faster than the rate of change in the atmospheric precipitable water capacity with a warming climate. However, the response of extreme precipitation depends on the type of storm supported by the meteorological environment. Here using long-term satellite, surface radar and rain-gauge network data and atmospheric reanalyses, we show that the observed increases in springtime total and extreme rainfall in 36 the central U.S. are dominated by mesoscale convective systems (MCSs), the largestmore » type of convective storm, with increased frequency and intensity of long-lasting MCSs. A strengthening of the southerly low-level jet and its associated moisture transport in the Central/Northern Great Plains, in the overall climatology and particularly on days with long-lasting MCSs, accounts for the changes in the precipitation produced by these storms.« less

Use the High-Resolution Numerical Model to Simulate Typhoon Morakot 2009

NASA Technical Reports Server (NTRS)

Tao, Wei-Kuo; Shi, Jainn J.; Lin, Pay-Liam

2010-01-01

Typhoon Morakot struck Taiwan on the night of Friday August 7th, 2009 as a category 2 storm with sustained winds of 85 knots (92 mph). Although the center made landfall in Hualien county along the central cast coast of Taiwan and passed over the central northern part of the island, it was southern Taiwan that received the worst effects of the storm where locally as Much as 2200 mm (2.2 m) of rain were reported, resulting in the worst flooding there in 50 years. The result of the enormous amount of rain has been massive flooding and devastating mudslides. More than 600 people are confirmed dead. In this paper, we will present the results from high-resolution (2-km) WRF for this typhoon case. The results showed that the model captured both in terms of maximum rainfall area and intensity. The model results also showed that the heavy amounts of rain over the southern portion of the island is due to persistent southwesterly flow associated with Morakot and it's circulation was able to draw up copious amounts of moisture from the South China Sea into southern Taiwan where it was able to interact with the steep topography. In the paper, we will also present results from sensitivity test of terrain heights and SST on the precipitation processes (rainfall) associated with Typhoon Morakot (2009), In addition, we will present high-resolution visualization (36 second and 2-km) to show the evolution of Typhoon Morakot.

Analysis with SfM on-motion method of July 2015 extreme rainfall impacts on the S-charl valley road in the Canton of Graubünden, Switzerland

NASA Astrophysics Data System (ADS)

Voumard, Jérémie; Jaboyedoff, Michel

2016-04-01

The 22-23th July 2015, two severe storms at one day interval have caused in Scuol, lower Engadine (Canton of Graubünden, Switzerland). The static storm cells produced up to 150 mm rain precipitations in three hours generating several debris flow. On 22 July 2015, three buildings in the Pradella hamlet near Scuol were damaged by a debris flow. People of two holiday camps, 100 children and 40 adults, were evacuated. Nobody was injured but the buildings damages are important. A day after, about 200 mm rain in a short time were measured in the same area. A car was been swept away by a debris flow in the Scuol village and its driver could escape at the last moment. The S-charl valley was isolated during more than one week by seven big debris flows and several little ones. About 100 people, in majority holidaymakers, were blocked in the S-charl hamlet without power supply during few days. Until the swiss army built a provisional emergency bridge to open the valley access, the only way to access the S-charl valley was by helicopter. Overall damages -roads infrastructures, buildings, drinking water supply, power supply and other- are estimated to one million Swiss Francs and the debris flow volume is estimated to 100'00 cubic meters. The S-charl valley roadsides were photographed fifteen days before the extreme storm event from an on-motion vehicle. The same roadsides were photographed twenty days after the event with the same acquisition methodology. 3D point clouds from Structure of Motion (SfM) from the -before and after event- pictures have been produced and compared. Thus, is was possible to evaluate the number of debris flows that occurred in the S-charl valley and estimate their volume in the roadsides. This study case allows to evaluate the low-cost SfM on-motion methodology and to give theirs main advantages and disadvantages when it is used to estimate changes roadsides due to a natural hazard event.

Floods in Kansas City, Missouri and Kansas, September 12-13, 1977

USGS Publications Warehouse

Hauth, Leland D.; Carswell, William J.

1978-01-01

The storm of September 12-13, 1977, produced as much as 16 inches of rainfall in the Kansas City, Missouri-Kansas area, left 25 persons dead, many homeless, and caused over 50 million dollars in damages.Data from National Weather Service recording rain gages indicate the storm came in two bursts within 24 hours. Flood hydrographs developed from streamflow records in the area also reflect the two events, with the second yielding the greater runoff.Peak discharges were determined during and after flood at gaging stations and selected miscellaneous locations. Peak discharges in areas of great rainfall depths were well over the criteria for the 100-year flood.

Hydrologic response for a high-elevation storm in the South Dakota Black Hills

USGS Publications Warehouse

Bunkers, Matthew J.; Smith, Melissa; Driscoll, Daniel G.; Hoogestraat, Galen K.

2015-01-01

A group of thunderstorms produced >4 in of rain during four periods of progressively more intense rainfall across a small part of a relatively high-elevation area of the northern Black Hills on 5 August 2014. The resulting hydrologic response was noteworthy in two very small headwater drainage basins, where the measured peak flows are by far the largest—relative to drainage area—ever documented for the high-elevation Limestone Plateau area. However, peak flows attenuated quickly in a downstream direction owing to the storms tracking perpendicular to the drainage direction, moderately dry antecedent conditions, and progressive widening of the valley bottoms.

Tracking rainfall impulses through progressively larger drainage basins in steep forested terrain

Treesearch

R. R. Ziemer; R. M. Rice

1990-01-01

Abstract - The precision of timing devices in modern electronic data loggers makes it possible to study the routing of water through small drainage basins having rapid responses to hydrologic impulses. Storm hyetographs were measured using digital tipping bucket rain gauges and their routing was observed at headwater piezometers located mid-slope, above a swale, and...

The Journey to Recovery

ERIC Educational Resources Information Center

Reiman, Mary

2012-01-01

When 250 employees of Lincoln Public Schools (LPS) in Lincoln, Nebraska, left their workspaces in the administration building on Friday, May 25, 2011, they thought the only thing that was significant was that it was the last day of the 2010-2011 school year. However, on Monday evening, May 30, 2011, during a wind and rain storm, the 90,000 square…

NOAA's world-class weather and climate prediction center opens at

Science.gov Websites

StumbleUpon Digg More Destinations NOAA's world-class weather and climate prediction center opens at currents and large-scale rain and snow storms. Billions of earth observations from around the world flow operations. Investing in this center is an investment in our human capital, serving as a world class facility

Climatic Change and Dynamics of Northern Hemisphere Storm-tracks: Changes in Transient Eddies Behavior

NASA Astrophysics Data System (ADS)

Martynova, Yuliya; Krupchatnikov, Vladimir

2013-04-01

An evidence of our understanding of the general circulation is whether we can predict changes in the general circulation that might be associated with past or future climate changes. Changes in the location, intensity or seasonality of major climatological features of the general circulation could be more important than average temperature changes, particularly where these changes could affect local hydrology, energy balances, etc. Under these major climatological features we assume the poleward expansion of the tropical circulation (Hadley circulation), static stability (changes in the vertical temperature structure of the atmosphere), role of SST forcing, sea ice extension, extratropical eddies behavior. We have a question: would the climate change significantly affect the location and intensity of midlatitude storm-tracks and associated jets? Mean-flow interaction in midlatitudes produces low-frequency variations in the latitude of the jets. It is reasonable to think that a modest climate change might significantly affects the jets location and their associated storm tracks. The storm-tracks are defined as the region of strong baroclinicity (maximum meridional temperature gradient), which are determined on the basis of eddy statistics like eddy fluxes of angular momentum, energy, and water (with the use of high-bandpass filter). In the Northern Hemisphere, there are two major storms: in the region of Atlantic and Pacific. The storm-tracks play important role in the dynamics of weather and climate. They affect the global energy cycle and the hydrological cycle, and as a result they bring heavy rains and other hazardous weather phenomena in the middle latitudes. The recent increase in global tropopause heights is closely associated with systematic temperature changes below and above the tropopause. Temperature increases in the troposphere and decreases in the stratosphere. The pattern of warming and cooling also affects the zonal wind structure in the region of the subtropical upper troposphere and lower stratosphere (UTLS). Extratropical tropospheric eddies play a central role in this mechanism. The eddies tend to move eastward with the zonal flow and equatorward toward the subtropics until they reach their critical latitudes, where their phase speed equals the speed of the background zonal flow. This work is partially supported by the Ministry of education and science of the Russian Federation (con-tract #8345), SB RAS project VIII.80.2.1, RFBR grant #11-05-01190a, and integrated project SB RAS #131.

Distributions of typical contaminant species in urban short-term storm runoff and their fates during rain events: a case of Xiamen City.

PubMed

Wei, Qunshan; Zhu, Gefu; Wu, Peng; Cui, Li; Zhang, Kaisong; Zhou, Jingjing; Zhang, Wenru

2010-01-01

The pollutants in urban storm runoff, which lead to an non-point source contamination of water environment around cities, are of great concerns. The distributions of typical contaminants and the variations of their species in short term storm runoff from different land surfaces in Xiamen City were investigated. The concentrations of various contaminants, including organic matter, nutrients (i.e., N and P) and heavy metals, were significantly higher in parking lot and road runoff than those in roof and lawn runoff. The early runoff samples from traffic road and parking lot contained much high total nitrogen (TN 6-19 mg/L) and total phosphorus (TP 1-3 mg/L). A large proportion (around 60%) of TN existed as total dissolved nitrogen (TDN) species in most runoff. The percentage of TDN and the percentage of total dissolved phosphorus remained relatively stable during the rain events and did not decrease as dramatically as TN and TP. In addition, only parking lot and road runoff were contaminated by heavy metals, and both Pb (25-120 microg/L) and Zn (0.1-1.2 mg/L) were major heavy metals contaminating both runoff. Soluble Pb and Zn were predominantly existed as labile complex species (50%-99%), which may be adsorbed onto the surfaces of suspended particles and could be easily released out when pH decreased. This would have the great impact to the environment.

Preparation and response in case of natural disasters: Cuban programs and experience.

PubMed

Mas Bermejo, Pedro

2006-01-01

Inadequate preparation for national disasters is frequently particularly devastating in lower income countries. The Cuba's location has a diversity of potential natural disasters, including hurricanes, non-tropical depressions, tropical storms, tropical cyclones, and severe local storms, all with intense rains and winds, earthquakes and droughts. Cuban preparation, at all levels, is geared to these predominant threats. Planning for natural disasters is integral to the political and economic life of Cuba, nationally and locally. On several occasions, United Nations (UN) officials have pointed to Cuba as a model for developing countries preparing for hurricanes and other natural disasters. A global policy for managing the risks of natural disasters could improve continuity of assistance for development and reduce the necessity of humanitarian aid. Planning in advance of disasters is a feasible way of helping people, by reducing expenses of emergencies, recuperation, and reconstruction. As climate changes accelerate, many researchers fear a period of irreversible and uncontrollable change. While the atmosphere continues to warm, it generates more intense rains, more frequent heat waves, and more ferocious storms. Thus, achieving better protection of developing countries from an increasing onslaught of natural disasters will only grow in importance. Even though Cuba's contribution to know-how has been recognized by United Nations' officials, progress toward more adequate preparation worldwide has been slow. To support other countries beyond conveying the lessons, Cuba now offers specially trained personnel to cooperate immediately with any country suffering a natural disaster.

Satellite passive microwave rain rate measurement over croplands during spring, summer and fall

NASA Technical Reports Server (NTRS)

Spencer, R. W.

1984-01-01

Rain-rate algorithms for spring, summer and fall that have been developed from comparisons between the brightness temperatures measured by the Nimbus-7 Scanning Multichannel Microwave Radiometer (SMMR) and rain rates derived from operational WSR-57 radars over land are described. Data were utilized from a total of 25 SMMR passes and 234 radars, resulting in about 12,000 observations of about 1600 sq/km areas. Multiple correlation coefficients of 0.63, 0.80 and 0.75 are achieved for the spring, summer and fall algorithms, respectively. Most of this information is in the form of multifrequency contrast in brightness temperature, which is interpreted as a measurement of the degree to which the land-emitted radiation is attenuated by the rain systems. The SMMR 37-GHz channel has more information on rain rate than any other channel. By combining the lower frequency channels with the 37-GHz observations, variations in land and precipitation thermometric temperatures can be removed, leaving rain attenuation as the major effect on brightness temperature. Polarization screening at 37 GHz is found to be sufficient to screen out cases of wet ground, which is only important when the ground is relatively vegetation free. Heavy rain cases are found to be significant part of the algorithms' success, because of the strong microwve signatures (low-brightness temperatures) that result from the presence of precipitation-sized ice in the upper portions of heavily precipitating storms. If IR data are combined with the summer microwave data, an improved (0.85) correlation with radar rain rates is achieved.

Strong Extratropical Cyclone Over the US Midwest

NASA Image and Video Library

2010-10-29

NASA image acquired October 26, 2010 The storm that swept across the center of the United States on October 26 and October 27, 2010, was memorable to those who experienced it because of its strong winds, rain, hail, and widespread tornadoes. Meteorologists get excited about the storm because it set a record for the lowest pressure (not associated with a hurricane) measured over land in the continental United States. At 5:13 p.m. CDT, the weather station in Bigfork, Minnesota recorded 955.2 millibars (28.21 inches of pressure). Pressure is one indicator of a storm’s strength, and this measurement corresponds to the pressure seen in a Category 3 hurricane. This image, taken by the GOES satellite on October 26, shows the storm system circling around the area of extreme low pressure. Such extratropical cyclones form over the United States in the spring and fall, when the temperature difference from north to south is large. Warm, high-pressure air rushes toward the cooler, low-pressure air in the north. Because the Earth is rotating, the air moving in ends up circling the area of low pressure, creating the cyclone shown in the image. The intensity of the storm is determined by the pressure difference between the center and the outer edges. Extreme low pressure in the center of the storm, therefore, is an indicator that the storm was very intense. The animation shows the storm developing starting late on October 25 and running through October 27. The cyclone formed very quickly on October 26, taking a distinctive comma shape as the day went on. The storm developed so quickly, in fact, that it is classified as a bomb, an extremely fast developing storm (dropping at least one millibar of pressure per hour for 24 hours), more common over water than land. The storm was also huge. Though the area of low pressure is centered over the Upper Midwest, the storm reached from the Gulf of Mexico into Canada, and from the Rocky Mountains to the Atlantic Ocean. Extratropical cyclones bring an array of unsettled weather, including strong wind, rain, hail, and tornadoes, and this cyclone brought all of that. On October 26–27, winds gusted up to 78 miles per hour in Michigan, with high winds throughout the Midwest. The National Weather Service reported 61 tornadoes over the two days. Heavy snow also fell in the north. NASA Earth Observatory imagery created by Jesse Allen, using imagery provided courtesy of the NASA GOES Project Science Office. Caption by Holli RIebeek. Instrument: GOES Credit: NASA Earth Observatory NASA Goddard Space Flight Center enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission. Follow us on Twitter Join us on Facebook

The influence of particle size on the first flush strength of urban stormwater runoff.

PubMed

Morgan, D; Johnston, P; Osei, K; Gill, L

2017-10-01

The presence of a first flush (FF) of suspended solids (SS) in stormwater runoff has important implications for the design of treatment facilities, as does the particle size of solids. Whilst numerous studies have examined the FF behaviour of SS, few have disaggregated FF trends by particle size. In this study, the FF behaviour of SS was investigated in five size ranges, sampled from an urban stormwater drainage system located in Dublin, Ireland. A weak FF was exhibited in the gross fraction of SS, with just two events from 14 transporting more than 50% of the SS mass in the first 25% of runoff, implying that treatment structures should be capable of removing SS throughout the storm event. In the majority of rain events, the FF strength increased with decreasing particle size, probably related to the lower intensities required to dislodge solids at the onset of rainfall. Although FF strength was correlated with rain event characteristics, prediction intervals were too broad to confirm FF presence based on rainfall data alone. Therefore, the design of smaller treatment volumes based on an assumption of FF must be justified by local monitoring data.

Applications of Hobbyist Electronics in Monitoring Stemflow Processes: Preliminary Insights and Results

NASA Astrophysics Data System (ADS)

Carlyle-Moses, D. E.; Turner, B.; Hill, D. J.

2016-12-01

Leveraging the power and adaptability of inexpensive, accessible hobbyist electronics it has been possible to gain insights into the processes governing stemflow. The sensor platform utilizes an Arduino® microcontroller equipped with an ultrasonic sensor and wetness sensor as well as a GPS unit for accurate timestamps. The wetness sensor, which is attached to the terminus of a collection tube diverting water entering the stemflow collar to a collection vessel, provides the precise time in which stemflow commences. In turn, this time can be compared with the time stamp record of a high precision tipping-bucket rain gauge so that the rain depth required for stemflow generation can be derived. In addition, the ultrasonic sensor mounted above the stemflow collection vessel monitors changes in water depth over time. The changes in water depth are then converted to volumetric changes allowing for reasonable approximations of stemflow flow rates throughout the storm event. As a trial, the stemflow monitoring platform was deployed from May 1 to June 30, 2016 on an ornamental Green Ash (Fraxinus pennsylvanica Marsh.) tree on the grounds of Thompson Rivers University in Kamloops, British Columbia, Canada (500 40' 25" N, 1200 21' 50" W). The tree was in full-leaf condition, was 7.4 m in height and had a diameter at breast height of 10.8 cm. Rain totaled 77.2 mm during the study and was distributed over 15 events (mean = 5.1 mm, range = 0.2 - 14.3 mm), with the five smallest rain events (0.2 - 1.3 mm) not producing stemflow. The study period funneling ratio was 14.0 (event range = 0.0 - 40.0). Regression analysis revealed that for events in which stemflow was produced, rainfall depth explained only 50.2 percent of the variation in event stemflow volumes. The variant nature of stemflow in our study was a consequence of both highly variable mean event flow rates once stemflow had commenced (mean = 0.197 L / mm of rain, coefficient of variation = 0.67, range = 0.009 - 0.444 L / mm), as well as widely differing rain depth thresholds required for stemflow generation (mean = 2.4 mm, coefficient of variation = 0.58, range = 0.8 - 5.2 mm). Future work, including expanding the study (longer study period and more trees) and examining the role of storm meteorology on both threshold rain depths and stemflow rates will be discussed.

Active and passive microwave measurements in Hurricane Allen

NASA Technical Reports Server (NTRS)

Delnore, V. E.; Bahn, G. S.; Grantham, W. L.; Harrington, R. F.; Jones, W. L.

1985-01-01

The NASA Langley Research Center analysis of the airborne microwave remote sensing measurements of Hurricane Allen obtained on August 5 and 8, 1980 is summarized. The instruments were the C-band stepped frequency microwave radiometer and the Ku-band airborne microwave scatterometer. They were carried aboard a NOAA aircraft making storm penetrations at an altitude of 3000 m and are sensitive to rain rate, surface wind speed, and surface wind vector. The wind speed is calculated from the increase in antenna brightness temperature above the estimated calm sea value. The rain rate is obtained from the difference between antenna temperature increases measured at two frequencies, and wind vector is determined from the sea surface normalized radar cross section measured at several azimuths. Comparison wind data were provided from the inertial navigation systems aboard both the C-130 aircraft at 3000 m and a second NOAA aircraft (a P-3) operating between 500 and 1500 m. Comparison rain rate data were obtained with a rain radar aboard the P-3. Evaluation of the surface winds obtained with the two microwave instruments was limited to comparisons with each other and with the flight level winds. Two important conclusions are drawn from these comparisons: (1) the radiometer is accurate when predicting flight level wind speeds and rain; and (2) the scatterometer produces well behaved and consistent wind vectors for the rain free periods.

Flood of July 1-2, 1987, in north-central Ohio

USGS Publications Warehouse

Mayo, R.I.; Mangus, J.P.

1989-01-01

During the night of July 1 and early morning of July 2, 1987, an intense summer storm produced flooding on headwater streams of the Scioto, Sandusky, and Mohican River in north-central Ohio. The heaviest flooding and resulting flood damage occurred in a five-county area in the north-central part of the state. From 3 to nearby 6 inches of rain fell in less than 10 hours on rain-saturated soil, and produced flooding that resulted in more than $20 million in damages. Estimated peak discharged for several of the small streams affected ranged from 1 to 2 1/2 times the magnitude of the 50-year flood of these sites.

Characteristics of the overflow pollution of storm drains with inappropriate sewage entry.

PubMed

Yin, Hailong; Lu, Yi; Xu, Zuxin; Li, Huaizheng; Schwegler, Benedict R

2017-02-01

To probe the overflow pollution of separate storm drains with inappropriate sewage entries, in terms of the relationship between sewage entries and the corresponding dry-weather and wet-weather overflow, the monitoring activities were conducted in a storm drainage system in the Shanghai downtown area (374 ha). In this study site, samples from inappropriately entered dry-weather sewage and the overflow due to storm pumps operation on dry-weather and wet-weather days were collected and then monitored for six water quality constituents. It was found that overflow concentrations of dry-weather period could be higher than those of wet-weather period; under wet-weather period, the overflow concentrations of storm drains were close to or even higher than that of combined sewers. Relatively strong first flush mostly occurred under heavy rain that satisfied critical rainfall amount, maximum rainfall intensity, and maximum pumping discharge, while almost no first flush effect or only weak first flush effect was found for the other rainfall events. Such phenomenon was attributed to lower in-line pipe storage as compared to that of the combined sewers, and serious sediment accumulation within the storm pipes due to sewage entry. For this kind of system, treating a continuous overflow rate is a better strategy than treating the maximum amount of early part of the overflow. Correcting the key inappropriate sewage entries into storm drains should also be focused.

Tropical Storm Ana off the Carolinas

NASA Image and Video Library

2015-05-14

At about 6:00 a.m. EDT (10:00 UTC) on May 10, 2015, Tropical Storm Ana made landfall between Myrtle Beach and North Myrtle Beach, South Carolina. One day earlier, on the morning of May 9, the Moderate Resolution Imaging Spectroradiometer (MODIS) on NASA’s Terra satellite acquired this true-color image of the storm off the coast of the Carolinas. At the time, Ana had just evolved from a subtropical storm to a tropical storm with maximum sustained winds of 93 kilometers (58 miles) per hour. Ana’s life ashore was brief – the storm was downgraded to a tropical depression at 2:00 p.m. EDT (14:00 UTC) on May 10. During that time, parts of South Carolina and eastern North Carolina was drenched with heavy rain – some areas reported over 6 inches of rainfall – and heavy winds. A water spout was reported in Dare County, North Carolina, and the storm contributed to significant beach erosion along the coast. Credit: NASA/GSFC/Jeff Schmaltz/MODIS Land Rapid Response Team NASA image use policy. NASA Goddard Space Flight Center enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission. Follow us on Twitter Like us on Facebook Find us on Instagram

Microphysics, Meteorology, Microwave and Modeling of Mediterranean Storms: The M(sup 5) Problem

NASA Technical Reports Server (NTRS)

Smith, Eric A.; Fiorino, Steven; Mugnai, Alberto; Panegrossi, Giulia; Tripoli, Gregory; Starr, David (Technical Monitor)

2001-01-01

Comprehensive understanding of the microphysical nature of Mediterranean storms requires a combination of in situ meteorological data analysis and radar-passive microwave data analysis, effectively integrated with numerical modeling studies at various scales, particularly from synoptic scale down to mesoscale. The microphysical properties of and their controls on severe storms are intrinsically related to meteorological processes under which storms have evolved, processes which eventually select and control the dominant microphysical properties themselves. Insofar as hazardous Mediterranean storms, highlighted by the September 25-28/1992 Genova flood event, the October 5-7/1998 Friuli flood event, and the October 13-15/2000 Piemonte flood event (all taking place in northern Italy), developing a comprehensive microphysical interpretation requires an understanding of the multiple phases of storm evolution and the heterogeneous nature of precipitation fields within the storm domains. This involves convective development, stratiform transition and decay, orographic lifting, and sloped frontal lifting proc esses. This also involves vertical motions and thermodynamical instabilities governing physical processes that determine details of the liquid/ice water contents, size distributions, and fall rates of the various modes of hydrometeors found within the storm environments. This paper presents detailed 4-dimensional analyses of the microphysical elements of the three severe Mediterranean storms identified above, investigated with the aid of SSM/I and TRMM satellite measurements (and other remote sensing measurements). The analyses are guided by nonhydrostatic mesoscale model simulations at high resolution of the intense rain producing portions of the storm environments. The results emphasize how meteorological controls taking place at the large scale, coupled with localized terrain controls, ultimately determine the most salient features of the bulk microphysical properties of the storms. These results have bearing on precipitation remote sensing from space, and the role of modeling in designing precipitation retrieval algorithms.

Characterizing the Relationships Among Lightning and Storm Parameters: Lightning as a Proxy Variable

NASA Technical Reports Server (NTRS)

Goodman, S. J.; Raghavan, R.; William, E.; Weber, M.; Boldi, B.; Matlin, A.; Wolfson, M.; Hodanish, S.; Sharp. D.

1997-01-01

We have gained important insights from prior studies that have suggested relationships between lightning and storm growth, decay, convective rain flux, vertical distribution of storm mass and echo volume in the region, and storm energetics. A study was initiated in the Summer of 1996 to determine how total (in-cloud plus ground) lightning observations might provide added knowledge to the forecaster in the determination and identification of severe thunderstorms and weather hazards in real-time. The Melbourne Weather Office was selected as a primary site to conduct this study because Melbourne is the only site in the world with continuous and open access to total lightning (LDAR) data and a Doppler (WSR-88D) radar. A Lightning Imaging Sensor Data Applications Demonstration (LISDAD) system was integrated into the forecaster's workstation during the Summer 1996 to allow the forecaster to interact in real-time with the multi-sensor data being displayed. LISDAD currently ingests LDAR data, the cloud-to-ground National Lightning Detection Network (NLDN) data, and the Melbourne radar data in f real-time. The interactive features provide the duty forecaster the ability to perform quick diagnostics on storm cells of interest. Upon selection of a storm cell, a pop-up box appears displaying the time-history of various storm parameters (e.g., maximum radar reflectivity, height of maximum reflectivity, echo-top height, NLDN and LDAR lightning flash rates, storm-based vertically integrated liquid water content). This product is archived to aid on detailed post-analysis.

A vision-based tool for the control of hydraulic structures in sewer systems

NASA Astrophysics Data System (ADS)

Nguyen, L.; Sage, D.; Kayal, S.; Jeanbourquin, D.; Rossi, L.

2009-04-01

During rain events, the total amount of the wastewater/storm-water mixture cannot be treated in the wastewater treatment plant; the overflowed water goes directly into the environment (lakes, rivers, streams) via devices called combined sewers overflows (CSOs). This water is untreated and is recognized as an important source of pollution. In most cases, the quantity of overflowed water is unknown due to high hydraulic turbulences during rain events; this quantity is often significant. For this reason, the monitoring of the water flow and the water level is of crucial environmental importance. Robust monitoring of sewer systems is a challenging task to achieve. Indeed, the environment inside sewers systems is inherently harsh and hostile: constant humidity of 100%, fast and large water level changes, corrosive atmosphere, presence of gas, difficult access, solid debris inside the flow. A flow monitoring based on traditional probes placed inside the water (such as Doppler flow meter) is difficult to conduct because of the solid material transported by the flow. Probes placed outside the flow such as ultrasonic water level probes are often used; however the measurement is generally done on only one particular point. Experience has shown that the water level in CSOs during rain events is far from being constant due to hydraulic turbulences. Thus, such probes output uncertain information. Moreover, a check of the data reliability is impossible to achieve. The HydroPix system proposes a novel approach to the monitoring of sewers based on video images, without contact with the water flow. The goal of this system is to provide a monitoring tool for wastewater system managers (end-users). The hardware was chosen in order to suit the harsh conditions of sewers system: Cameras are 100% waterproof and corrosion-resistant; Infra-red LED illumination systems are used (waterproof, low power consumption); A waterproof case contains the registration and communication system. The monitoring software has the following requirements: visual analysis of particular hydraulic behavior, automatic vision-based flow measurements, automatic alarm system for particular events (overflows, risk of flooding, etc), database for data management (images, events, measurements, etc.), ability to be controlled remotely. The software is implemented in modular server/client architecture under LabVIEW development system. We have conducted conclusive in situ tests in various sewers configurations (CSOs, storm-water sewerage, WWTP); they have shown the ability of the HydroPix to perform accurate monitoring of hydraulic structures. Visual information demonstrated a better understanding of the flow behavior in complex and difficult environment.

Large Eddy Simulations of Severe Convection Induced Turbulence

NASA Technical Reports Server (NTRS)

Ahmad, Nash'at; Proctor, Fred

2011-01-01

Convective storms can pose a serious risk to aviation operations since they are often accompanied by turbulence, heavy rain, hail, icing, lightning, strong winds, and poor visibility. They can cause major delays in air traffic due to the re-routing of flights, and by disrupting operations at the airports in the vicinity of the storm system. In this study, the Terminal Area Simulation System is used to simulate five different convective events ranging from a mesoscale convective complex to isolated storms. The occurrence of convection induced turbulence is analyzed from these simulations. The validation of model results with the radar data and other observations is reported and an aircraft-centric turbulence hazard metric calculated for each case is discussed. The turbulence analysis showed that large pockets of significant turbulence hazard can be found in regions of low radar reflectivity. Moderate and severe turbulence was often found in building cumulus turrets and overshooting tops.

Weak linkage between the heaviest rainfall and tallest storms.

PubMed

Hamada, Atsushi; Takayabu, Yukari N; Liu, Chuntao; Zipser, Edward J

2015-02-24

Conventionally, the heaviest rainfall has been linked to the tallest, most intense convective storms. However, the global picture of the linkage between extreme rainfall and convection remains unclear. Here we analyse an 11-year record of spaceborne precipitation radar observations and establish that a relatively small fraction of extreme convective events produces extreme rainfall rates in any region of the tropics and subtropics. Robust differences between extreme rainfall and convective events are found in the rainfall characteristics and environmental conditions, irrespective of region; most extreme rainfall events are characterized by less intense convection with intense radar echoes not extending to extremely high altitudes. Rainfall characteristics and environmental conditions both indicate the importance of warm-rain processes in producing extreme rainfall rates. Our results demonstrate that, even in regions where severe convective storms are representative extreme weather events, the heaviest rainfall events are mostly associated with less intense convection.

Thirty-one years of debris-flow observation and monitoring near La Honda, California, USA

USGS Publications Warehouse

Wieczorek, G.F.; Wilson, R.C.; Ellen, S.D.; Reid, M.E.; Jayko, A.S.

2007-01-01

From 1975 until 2006,18 intense storms triggered at least 248 debris flows within 10 km2 northwest of the town of La Honda within the Santa Cruz Mountains, California. In addition to mapping debris flows and other types of landslides, studies included soil sampling and geologic mapping, piezometric and tensiometer monitoring, and rainfall measurement and recording. From 1985 until 1995, a system with radio telemetered rain gages and piezometers within the La Honda region was used for issuing six debris-flow warnings within the San Francisco Bay region through the NOAA ALERT system. Depending upon the relative intensity of rainfall during storms, debris flows were generated from deep slumps, shallow slumps, shallow slides in colluvium and shallow slides over bedrock. Analysis shows the storms with abundant antecedent rainfall followed by several days of steady heavy intense rainfall triggered the most abundant debris flows. ?? 2007 millpress.

Effect of Watershed Cover on Overland Flow from a Major Storm in Southwestern Wisconsin

Treesearch

Richard S. Sartz

1969-01-01

A runoff study in the Driftless Area showed that both total flow and peak rate of flow from a 3-hour, 4-inch rain were strongly affected by the watershed cover. Peak flows ranged from 2.42 inches per hour for alfalfa meadow to 0.010 inch per hour for undisturbed forested watersheds was surprisingly similar.

Earth Observations taken by the Expedition Seven crew

NASA Image and Video Library

2003-07-15

ISS007-E-10239 (15 July 2003) --- The crew of the International Space Station had a great seat from which to observe tropical storm Claudette as she turned into a hurricane and came ashore with high winds and heavy rains that drenched their Houston home base and other Texas areas. This digital image was recorded at 13:25:10 GMT, July 15, 2003.

Earth Observations taken by the Expedition Seven crew

NASA Image and Video Library

2003-07-15

ISS007-E-10246 (15 July 2003) --- The crew of the International Space Station had a great seat from which to observe tropical storm Claudette as she turned into a hurricane and came ashore with high winds and heavy rains that drenched their Houston home base and other Texas areas. This digital image was recorded at 13:26:54 GMT, July 15, 2003

Earth Observations taken by the Expedition Seven crew

NASA Image and Video Library

2003-07-15

ISS007-E-10245 (15 July 2003) --- The crew of the International Space Station had a great seat from which to observe tropical storm Claudette as she turned into a hurricane and came ashore with high winds and heavy rains that drenched their Houston home base and other Texas areas. This digital image was recorded at 13:26:41 GMT, July 15, 2003

Soil-water relations of shallow forested soils during flash floods in West Virginia

Treesearch

James H. Patric

1981-01-01

On May 24, 1978, heavy rain caused flash flooding on densely forested land near Parsons, in Tucker County, West Virginia. Poststorm evidences of soil and water behavior were examined in detail on soils related to the Dekalb and Leetonia series. Other flash floods struck seven forested sections of the state in August. Less detailed observation after these storms...

Reverse auction results for implementation of decentralized retrofit best management practices in a small urban watershed (Cincinnati OH)Participatory storm water management and sustainability – what are the connections?

EPA Science Inventory

Urban stormwater is typically conveyed to centralized infrastructure, and there is great potential for reducing stormwater runoff quantity through decentralization. In this case we hypothesize that smaller-scale retrofit best management practices (BMPs) such as rain gardens and r...

Processess involved in the dispersal of Xanthomonas citri pv. citri from canker-infected citrus canopies, and in the infection of citrus foliage

USDA-ARS?s Scientific Manuscript database

Citrus canker (Xanthomonas citri subsp. citri, Xcc) is now considered endemic in Florida, and epidemics result in yield loss and market penalties both in Florida and elsewhere, where the pathogen occurs and susceptible citrus is cultivated. The bacterium is dispersed in rain splash, and storms with...

Processes involved in the dispersal of Xanthomonas citri pv. citri from canker-infectd citrus canopies, and in the infection of citrus foliage

USDA-ARS?s Scientific Manuscript database

Citrus canker (Xanthomonas citri subsp. citri, Xcc) is now considered endemic in Florida, and epidemics result in yield loss and market penalties both in Florida, and elsewhere where the pathogen occurs, and susceptible citrus is cultivated. The bacterium is dispersed in rain splash, and storms wit...

The depth-dependence of rain noise in the Philippine Sea.

PubMed

Barclay, David R; Buckingham, Michael J

2013-05-01

During the Philippine Sea experiment in May 2009, Deep Sound, a free-falling instrument platform, descended to a depth of 5.1 km and then returned to the surface. Two vertically aligned hydrophones monitored the ambient noise continuously throughout the descent and ascent. A heavy rainstorm passed over the area during the deployment, the noise from which was recorded over a frequency band from 5 Hz to 40 kHz. Eight kilometers from the deployment site, a rain gauge on board the R/V Kilo Moana provided estimates of the rainfall rate. The power spectral density of the rain noise shows two peaks around 5 and 30 kHz, elevated by as much as 20 dB above the background level, even at depths as great as 5 km. Periods of high noise intensity in the acoustic data correlate well with the rainfall rates recovered from the rain gauge. The vertical coherence function of the rain noise has well-defined zeros between 1 and 20 kHz, which are characteristic of a localized source on the sea surface. A curve-fitting procedure yields the vertical directional density function of the noise, which is sharply peaked, accurately tracking the storm as it passed over the sensor station.

Geochemistry of the Mattole River in Northern California

USGS Publications Warehouse

Kennedy, Vance C.; Malcolm, Ronald L.

1977-01-01

The chemical composition of streams can vary greatly with changing discharge during storm runoff. These chemical changes are related to the pathways of various water parcels from the time they fall as rain until they enter the stream, and to the interactions between water and sediment during transport downstream. In order to understand better the chemical variations during storms, an extensive investigation was made of the Mattole River, a chemically clean coastal stream in Mendocino County, California. The Mattole drains a topographically mature basin of 620 sw km which has relief of about 1200 m, a long summer dry season, and mean annual rainfall of about 2300 mm. The stream flow is composed of seasonally varying proportions of four flow components, namely, surface runoff, quick-return flow (rainfall having brief and intimate contact with the soil before entering the surface drainage), delayed-return flow, and base runoff. Each component is identified by its characteristic chemistry and by the time delay between rainfall and entrance into the stream. Information is also presented on rain chemistry, adsorption reactions of suspended sediments in the fresh and brackish environments, and compositional variation of river sediments with particle size. (Woodard-USGS)

Convective Mode and Mesoscale Heavy Rainfall Forecast Challenges during a High-Impact Weather Period along the Gulf Coast and Florida from 17-20 May 2016

NASA Astrophysics Data System (ADS)

Bosart, L. F.; Wallace, B. C.

2017-12-01

Two high-impact convective storm forecast challenges occurred between 17-20 May 2016 during NOAA's Hazardous Weather Testbed Spring Forecast Experiment (SFE) at the Storm Prediction Center. The first forecast challenge was 286 mm of unexpected record-breaking rain that fell on Vero Beach (VRB), Florida, between 1500 UTC 17 May and 0600 UTC 18 May, more than doubling the previous May daily rainfall record. The record rains in VRB occurred subsequent to the formation of a massive MCS over the central Gulf of Mexico between 0900-1000 UTC 17 May. This MCS, linked to the earlier convection associated with an anomalously strong subtropical jet (STJ) over the Gulf of Mexico, moved east-northeastward toward Florida. The second forecast challenge was a large MCS that formed over the Mexican mountains near the Texas-Mexican border, moved eastward and grew upscale prior to 1200 UTC 19 May. This MCS further strengthened offshore after 1800 UTC 19 May beneath the STJ. SPC SFE participants expected this MCS to move east-northeastward and bring heavy rain due to training echoes along the Gulf coast as far eastward as the Florida panhandle. Instead, this MCS transitioned into a bowing MCS that resembled a low-end derecho and produced a 4-6 hPa cold pool with widespread surface wind gusts between 35-50 kt. Both MCS events occurred in a large-scale baroclinic environment along the northern Gulf coast. Both MCS events responded to antecedent convection within this favorable large-scale environment. Rainfall amounts with the first heavy rain-producing MCS were severely underestimated by models and forecasters alike. The second MCS produced the greatest forecaster angst because rainfall totals were forecast too high (MCS propagated too fast) and severe wind reports were much more widespread than anticipated (because of cold pool formation). This presentation will attempt to untangle what happened and why it happened.

Inter-Comparison of CHARM Data and WSR-88D Storm Integrated Rainfall

NASA Technical Reports Server (NTRS)

Jedlovec, Gary J.; Meyer, Paul J.; Guillory, Anthony R.; Stellman, Keith; Limaye, Ashutosh; Arnold, James E. (Technical Monitor)

2002-01-01

A localized precipitation network has been established over a 4000 sq km region of northern Alabama in support of local weather and climate research at the Global Hydrology and Climate Center (GHCC) in Huntsville. This Cooperative Huntsville-Area Rainfall Measurement (CHARM) network is comprised of over 80 volunteers who manually take daily rainfall measurements from 85 sites. The network also incorporates 20 automated gauges that report data at 1-5 minute intervals on a 24 h a day basis. The average spacing of the gauges in the network is about 6 kin, however coverage in some regions benefit from gauges every 1-2 km. The 24 h rainfall totals from the CHARM network have been used to validate Stage III rainfall estimates of daily and storm totals derived from the WSR-88D radars that cover northern Alabama. The Stage III rainfall product is produced by the Lower Mississippi River Forecast Center (LMRFC) in support of their daily forecast operations. The intercomparisons between the local rain gauge and the radar estimates have been useful to understand the accuracy and utility of the Stage III data. Recently, the Stage III and CHARM rainfall measurements have been combined to produce an hourly rainfall dataset at each CHARM observation site. The procedure matches each CHARM site with a time sequence of Stage III radar estimates of precipitation. Hourly stage III rainfall estimates were used to partition the rain gauge values to the time interval over which they occurred. The new hourly rain gauge dataset is validated at selected points where 1-5 minute rainfall measurements have been made. This procedure greatly enhances the utility of the CHARM data for local weather and hydrologic modeling studies. The conference paper will present highlights of the Stage III intercomparison and some examples of the combined radar / rain gauge product demonstrating its accuracy and utility in deriving an hourly rainfall product from the 24 h CHARM totals.

Endurance of Australian dry-savannah cyanobacteria regulated by extra-cellular polysaccharides - EPS and environment

NASA Astrophysics Data System (ADS)

Williams, W.; Budel, B.; Reichenberger, H.; Rose, N.

2012-04-01

Cyanobacterial crusts are an important driver of ecosystem function throughout Queensland's dry savannah. Annually there is very little rainfall during the winter-dry season. In the summer-wet season build-up early storms precede its onset; days are low in humidity with high ambient (>40°C) and soil surface temperatures (60-74°C). In the wet season monsoon rains and tropical storms result in vast flooded plains and ephemeral wetlands, leaving the ground saturated for several weeks. At Boodjamulla National Park (NW Qld), cyanobacterial crusts were sampled during the dry season, after 125 days without rain. An Imaging PAM (Walz) was used to determine the resurrection and quantum yield of Photosystem II (PSII). The crusts were periodically watered for ten days and multiple PAM measurements were made on a daily basis. PSII in cyanobacteria showed no signs of resurrection; however new Nostoc colonies emerged on the eighth day. Microscopic examination revealed other cyanobacteria remained in a desiccated state and EPS seemed hydrophobic. In the following dry season, crust samples were preserved at 40°C at low humidity. During the wet season these samples were reintroduced into their natural environment of high humidity and subject to periodic rains. The resurrection of PSII commenced within two hours of the first rainfall and was fully functional within 24 hours at which time existing cyanobacterial cells rapidly re-hydrated and EPS exhibited hydrophilicity. These are the first field studies demonstrating the environmental conditions controlling the function of cyanobacterial EPS and the resurrection of PSII. Mass EPS production occurs several times throughout the wet season. Eventually, as the humidity drops, temperatures remain high and sunny conditions prevail the EPS hardens and dries forming thick hydrophobic polymeric surfaces. As temperatures rise and fall, crusts crack and curl, then start to disintegrate after the first rains of the wet season before new crusts start to grow.

Observed Recent Trends in Tropical Cyclone Rainfall Over Major Ocean Basins

NASA Technical Reports Server (NTRS)

Lau, K. M.; Zhou, Y. P.

2011-01-01

In this study, we use Tropical Rainfall Measuring Mission (TRMM) and Global Precipitation Climatology Project (GPCP) rainfall data together with historical storm track records to examine the trend of tropical cyclone (TC) rainfall in major ocean basins during recent decades (1980-2007). We find that accumulated total rainfall along storm tracks for all tropical cyclones shows a weak positive trend over the whole tropics. However, total rainfall associated with weak storms, and intense storms (Category 4-5) both show significant positive trends, while total rainfall associated with intermediate storms (Category1-3) show a significant negative trend. Storm intensity defined as total rain produced per unit storm also shows increasing trend for all storm types. Basin-wide, from the first half (1980-1993) to the second half (1994-2007) of the data period, the North Atlantic shows the pronounced increase in TC number and TC rainfall while the Northeast Pacific shows a significant decrease in all storm types. Except for the Northeast Pacific, all other major basins (North Atlantic, Northwest Pacific, Southern Oceans, and Northern Indian Ocean) show a significant increase in total number and rainfall amount in Category 4-5 storms. Overall, trends in TC rainfall in different ocean basins are consistent with long-term changes in the ambient large-scale environment, including SST, vertical wind shear, sea level pressure, mid-tropospheric humidity, and Maximum Potential Intensity (MPI). Notably the pronounced positive (negative) trend of TC rainfall in the North Atlantic (Northeast Pacific) appears to be related to the most (least) rapid increase in SST and MPI, and the largest decrease (increase) in vertical wind shear in the region, relative to other ocean basins.

Evolution of lightning in an isolated hailstorm of moderate size in the tropics

NASA Astrophysics Data System (ADS)

Kamra, A. K.; Pawar, S. D.

2007-10-01

Evolution of lightning activity in a tropical hailstorm of moderate size that developed in the premonsoon season at Pune (18°32'N, 73°51'E, 559 m above sea level) is studied from the measurements of surface electric field, the Maxwell current and thunder. Total flash rate is counted from the electric field record, and the cloud-to-ground (CG) flash rate is estimated from the visual observations. Precise timings of their occurrence were confirmed from the observations of overshoot in the Maxwell current records. The storm exhibited an almost constant rate of one CG flash every 1 to 2 min over the whole life time of the storm. The ratio of intracloud (IC) to CG flashes (IC/CG) increased with the increase in total flash rate. In the convective stage of the storm, field changes from consecutive flashes were generally found to alternate in polarity. Moreover, in this stage, field changes occur in pairs, the first field change of each pair being of negative polarity and the second one of positive polarity. The two field changes in a pair occur with an average time difference of 14.3 ± 8.4 s while two consecutive pairs appear after 29.3 ± 9.1 s. In between the convective and mature stages, our observations suggest the occurrence of the phenomenon of rain gush and the field excursion associated with falling precipitation. Development of the mature stage was marked with rapid transitions in the surface electric field and the Maxwell current polarities from negative to positive. Further, total flash rate and IC/CG ratio sharply increase, and the lightning-induced electric field changes become almost exclusively of negative polarity. Observations suggest possibly a lifting up of the charging region in mature stage of the storm. The dissipating stage of the storm witnessed hail and rain showers, sharp transition of electric field and the Maxwell current from positive to negative polarity and occurrence of a few positive CG discharges. Our observations are consistent with the general belief that that some lightning flashes, by neutralizing and depositing charge in the region of opposite polarity, change the charge distribution so as to trigger another discharge in the storm.

Scavenging of ammonia by raindrops in Saturn's great storm clouds

NASA Astrophysics Data System (ADS)

Delitsky, M. L.; Baines, Kevin

2016-10-01

Observations of the great Saturn storms of 2010-2011 by Cassini instruments showed a very large depletion in atmospheric ammonia. While dynamics will play a role, the very high solubility of ammonia in water may be another important contributor to ammonia depletion in storms. Ammonia exists in Earth's atmosphere and rainstorms dissolve ammonia to a great degree, leaving almost no NH3 in the atmosphere. Studies by Elperin et al (2011, 2013) show that scavenging of ammonia is greatest as a rainstorm starts and lessens as raindrops fall, tapering off to almost zero by the time the rain reaches the ground (Elperin et al 2009). Ammonia is reaching saturation as it dissolves in the aqueous solution. As concentration increases, NH3 is then converted to aqueous species (NH3)x.(H2O)y (Max and Chapados 2013).Ammonia has the highest solubility in water compared to all other gases in the Saturn atmosphere. The Henry's Law constant for NH3 in water is 60 M/atm at 25 C. For H2S, it is 0.001 M/atm. In Saturn storms, it is "raining UP": As water-laden storm clouds convectively rise, ammonia gas will be scavenged and go into solution to a great degree, whilst all the other gases remain mostly in the gas phase. Aqueous ammonia acts as an antifreeze: if ammonia is dissolved in water cloud droplets to the limit of its solubility, as water droplets rise, they can stay liquid (and continue to scavenge NH3) to well below their normal freezing point of 0 Celsius (273 K). The freezing point for a 30 wt % water-ammonia solution is ~189 K. The pressure level where T = 189 K is at 2.8 bars. The normal freezing point of water occurs at the 9 bar pressure level in Saturn's atmosphere. 2.8 bars occurs at the -51 km altitude (below the 1 bar level). 9 bars is at the -130 km level: a difference of 79 km. A water droplet containing 30 wt% NH3 can move upwards from 9 bars to 2.8 bars (79 km) and still remain liquid, only freezing above that altitude. Calculations by the E-AIM model show that ammonia becomes the dominant species as the water droplets rise and cool. Ammonia will be effectively depleted as it is scavenged into water droplets in Saturn's storms.

RainyDay: An Online, Open-Source Tool for Physically-based Rainfall and Flood Frequency Analysis

NASA Astrophysics Data System (ADS)

Wright, D.; Yu, G.; Holman, K. D.

2017-12-01

Flood frequency analysis in ungaged or changing watersheds typically requires rainfall intensity-duration-frequency (IDF) curves combined with hydrologic models. IDF curves only depict point-scale rainfall depth, while true rainstorms exhibit complex spatial and temporal structures. Floods result from these rainfall structures interacting with watershed features such as land cover, soils, and variable antecedent conditions as well as river channel processes. Thus, IDF curves are traditionally combined with a variety of "design storm" assumptions such as area reduction factors and idealized rainfall space-time distributions to translate rainfall depths into inputs that are suitable for flood hydrologic modeling. The impacts of such assumptions are relatively poorly understood. Meanwhile, modern precipitation estimates from gridded weather radar, grid-interpolated rain gages, satellites, and numerical weather models provide more realistic depictions of rainfall space-time structure. Usage of such datasets for rainfall and flood frequency analysis, however, are hindered by relatively short record lengths. We present RainyDay, an open-source stochastic storm transposition (SST) framework for generating large numbers of realistic rainfall "scenarios." SST "lengthens" the rainfall record by temporal resampling and geospatial transposition of observed storms to extract space-time information from regional gridded rainfall data. Relatively short (10-15 year) records of bias-corrected radar rainfall data are sufficient to estimate rainfall and flood events with much longer recurrence intervals including 100-year and 500-year events. We describe the SST methodology as implemented in RainyDay and compare rainfall IDF results from RainyDay to conventional estimates from NOAA Atlas 14. Then, we demonstrate some of the flood frequency analysis properties that are possible when RainyDay is integrated with a distributed hydrologic model, including robust estimation of flood hazards in a changing watershed. The U.S. Bureau of Reclamation is supporting the development of a web-based variant of RainyDay, a "beta" version of which is available at http://her.cee.wisc.edu/projects/rainyday/.

Benefits and limitations of using the weather radar for the definition of rainfall thresholds for debris flows. Case study from Catalonia (Spain).

NASA Astrophysics Data System (ADS)

Abancó, C.; Hürlimann, M.; Sempere, D.; Berenguer, M.

2012-04-01

Torrential processes such as debris flows or hyperconcentrated flows are fast movements formed by a mix of water and different amounts of unsorted solid material. They occur in steep torrents and suppose a high risk for the human settlements. Rainfall is the most common triggering factor for debris flows. The rainfall threshold defines the rainfall conditions that, when reached or exceeded, are likely to provoke one or more events. Many different types of empirical rainfall thresholds for landslide triggering have been defined. Direct measurements of rainfall data are normally not available from a point next to or in the surroundings of the initiation area of the landslide. For this reason, most of the thresholds published for debris flows have been established by data measured at the nearest rain gauges (often located several km far from the landslide). Only in very few cases, the rainfall data to analyse the triggering conditions of the debris flows have been obtained by weather (Doppler) radar. Radar devices present certain limitations in mountainous regions due to undesired reboots, but their main advantage is that radar data can be obtained for any point of the territory. The objective of this work was to test the use of the weather radar data for the definition of rainfall thresholds for debris-flow triggering. Thus, rainfall data obtained from 3 to 5 rain gauges and from radar were compared for a dataset of events occurred in Catalonia (Spain). The goal was to determine in which cases the description of the rainfall episode (in particular the maximum intensity) had been more accurate. The analysed dataset consists of: 1) three events occurred in the Rebaixader debris-flow monitoring station (Axial Pyrenees) including two hyperconcentrated flows and one debris flow; 2) one debris-flow event occurred in the Port Ainé ski resort (Axial Pyrenees); 3) one debris-flow event in Montserrat (Mediterranean Coastal range). The comparison of the hyetographs from the different devices showed that the reliability of the radar is higher for short, high intensity storms more than for long lasting, medium intensity ones. Additionally, the best fit corresponds to the situations where the storm nucleus is located near the source area of the debris flow. The results of the comparison between different rain gauges show similar trends. The ones located in the same valley as the debris flow usually show good results, but if there are orographic elements in-between the debris-flow torrent and the rain gauge or the distance is large, the results can imply a great error in the definition of rainfall intensity. Therefore, we can state that the reliability of the use of the weather radar to define rainfall thresholds is strongly depending on the type of the storm and the distance between the source area and the nucleus of the storm.

Hydrological Modeling of Rainfall-Watershed-Bioretention System with EPA SWMM

NASA Astrophysics Data System (ADS)

gülbaz, sezar; melek kazezyılmaz-alhan, cevza

2016-04-01

Water resources should be protected for the sustainability of water supply and water quality. Human activities such as high urbanization with lack of infrastructure system and uncontrolled agricultural facilities adversely affect the water resources. Therefore, recent techniques should be investigated in detail to avoid present and future problems like flood, drought and water pollution. Low Impact Development-Best Management Practice (LID-BMP) is such a technique to manage storm water runoff and quality. There are several LID storm water BMPs such as bioretention facilities, rain gardens, storm water wetlands, vegetated rooftops, rain barrels, vegetative swales and permeable pavements. Bioretention is a type of Low Impact Developments (LIDs) implemented to diminish adverse effects of urbanization by reducing peak flows over the surface and improving surface water quality simultaneously. Different soil types in different ratios are considered in bioretention design which affects the performance of bioretention systems. Therefore, in this study, a hydrologic model for bioretention is developed by using Environmental Protection Agency Storm Water Management Model (EPA SWMM). Part of the input data is supplied to the hydrologic model by experimental setup called Rainfall-Watershed-Bioretention (RWB). RWB System is developed to investigate the relation among rainfall, watershed and bioretention. This setup consists of three main parts which are artificial rainfall system, drainage area and four bioretention columns with different soil mixture. EPA SWMM is a dynamic simulation model for the surface runoff which develops on a watershed during a rainfall event. The model is commonly used to plan, analyze, and control storm water runoff, to design drainage system components and to evaluate watershed management of both urban and rural areas. Furthermore, EPA SWMM is a well-known program to model LID-Bioretention in the literature. Therefore, EPA SWMM is employed in drainage and bioretention modeling. Calibration of hydrologic model is made using part of the measured data in RWB System for drainage area and for each bioretention column separately. Finally, performance of the model is evaluated by comparing the model results with the experimental data collected in RWB system.

Numerical study of Tallinn storm-water system flooding conditions using CFD simulations of multi-phase flow in a large-scale inverted siphon

NASA Astrophysics Data System (ADS)

Kaur, K.; Laanearu, J.; Annus, I.

2017-10-01

The numerical experiments are carried out for qualitative and quantitative interpretation of a multi-phase flow processes associated with malfunctioning of the Tallinn storm-water system during rain storms. The investigations are focused on the single-line inverted siphon, which is used as under-road connection of pipes of the storm-water system under interest. A multi-phase flow solver of Computational Fluid Dynamics software OpenFOAM is used for simulating the three-phase flow dynamics in the hydraulic system. The CFD simulations are performed with different inflow rates under same initial conditions. The computational results are compared essentially in two cases 1) design flow rate and 2) larger flow rate, for emptying the initially filled inverted siphon from a slurry-fluid. The larger flow-rate situations are under particular interest to detected possible flooding. In this regard, it is anticipated that the CFD solutions provide an important insight to functioning of inverted siphon under a restricted water-flow conditions at simultaneous presence of air and slurry-fluid.

Rain in the U.S. Midwest

NASA Technical Reports Server (NTRS)

2007-01-01

The powerful storms that moved across the U.S. Midwest during the first week of May 2007 brought wind, hail, tornadoes, and drenching rain. This image shows rainfall totals over parts of Oklahoma, Kansas, and Nebraska between May 1 and May 8, based in part on measurements made by the Tropical Rainfall Measuring Mission (TRMM) satellite. More than 400 millimeters (15.7 inches) of rain fell over some regions, corresponding with locations where the National Weather Service reported severe weather. A wide swath of red and orange (between 240 and 400 millimeters of rain) arcs in a clockwise direction from western Oklahoma, through central Kansas, and into southeastern Nebraska. The reddish-orange bull's-eye over southeastern Louisiana is evidence of the torrential rains that pounded visitors to the annual New Orleans Jazz Festival. South-central Texas' Edward Plateau was soaked with more than 240 millimeters of rain during the period, as well. From May 4 to May 8, the National Weather Service received approximately 683 reports of severe weather, 140 of which were reports of tornadoes, including the massive F5 tornado that devastated the city of Greensburg, Kansas. Beyond the damaging winds and tornadoes, the torrential rain triggered extensive flooding throughout the Central Plains. On the evening of May 7, flood warnings were in effect from South Dakota to southern Texas, and by May 8, the Hydrologic Information Center reported moderate to major flooding at 53 stream gauge sites in South Dakota, Iowa, Kansas, Nebraska, Missouri, and Arkansas. The floods could be as severe as the 1993 flood, one of the costliest floods in U.S. history, reported the Associated Press.

Structure and Evolution of Band-shaped Convective Rainbands in Typhoon Marokot (2009)

NASA Astrophysics Data System (ADS)

Zhang, Y.

2012-12-01

Typhoon Morakot struck Taiwan on the night of Friday 7 August 2009 as a Category 1 storm (with sustained winds of 80 knots). Although the center made landfall in Hualien county along the central east coast of Taiwan, it was southern Taiwan that received the heaviest rainfall (2878 mm of rain in three days), resulting in the worst flooding over Taiwan in 50 years. This record-breaking rainfall is produced by the continuous impingement of typhoon rainbands with the steep terrain along the southern Central Mountain Range (CMR). In this study, rainband structures of Typhoon Morakot (2009) are analyzed and compared with the observations using outputs from the cloud-resolving WRF model with high spatial resolution (1-km horizontal grid spacing). The characteristics of the unique band-shaped convective rainband in TC Morakot are explained with respect to the following details: (i) horizontal shape, (ii) structure, and (iii) development and evolution process. The kinematic and precipitation structures of convective-scale elements in the Morakot rainbands are analyzed and compared with those of Hurricanes Katrina and Rita (2005).

Hurricane Agnes rainfall and floods, June-July 1972

USGS Publications Warehouse

Bailey, James F.; Patterson, James Lee; Paulhus, Joseph Louis Hornore

1975-01-01

Hurricane Agnes originated in the Caribbean Sea region in mid-June. Circulation barely reached hurricane intensity for a brief period in the Gulf of Mexico. The storm crossed the Florida Panhandle coastline on June 19, 1972, and followed an unusually extended overland trajectory combining with an extratropical system to bring very heavy rain from the Carolinas northward to New York. This torrential rain followed the abnormally wet May weather in the Middle Atlantic States and set the stage for the subsequent major flooding. The record-breaking floods occurred in the Middle Atlantic States in late June and early July 1972. Many streams in the affected area experienced peak discharges several times the previous maxima of record. Estimated recurrence intervals of peak flows at many gaging stations on major rivers and their tributaries exceeded 100 years. The suspended-sediment concentration and load of most flooded streams were also unusually high. The widespread flooding from this storm caused Agnes to be called the most destructive hurricane in United States history, claiming 117 lives and causing damage estimated at $3.1 billion in 12 States. Damage was particularly high in New York, Pennsylvania, Maryland, and Virginia. The detailed life history of Hurricane Agnes, including the tropical depression and tropical storm stages, is traced. Associated rainfalls are analyzed and compared with climatologic recurrence values. These are followed by a detailed description of the flood and streamflows of each affected basin. A summary of peak stages and discharges and comparison data for previous floods at 989 stations are presented. Deaths and flood damage estimates are compiled.

Two Perspectives on Keith

NASA Technical Reports Server (NTRS)

2002-01-01

Tropical storm Keith was born on Sept. 29 in the Caribbean, off the east coast of Honduras, and reached hurricane Category 3 intensity (winds in excess of 111 miles per hour) on Oct. 1. Hurricane Keith made landfall on Mexico's Yucatan Peninsula and northeastern Belize on Oct. 2, packing winds as high as 135 miles per hour and a storm surge of up to 6 feet above normal tide levels. Although the storm quickly weakened in intensity to a tropical storm (65 miles per hour), it moved slowly inland and dumped large amounts of rain on the region--exceeding 15 inches in some areas within a 24-hour period. Authorities in the area are warning residents of the potential for flooding and mudslides. NASA and NOAA satellites captured images of Hurricane Keith on Oct. 2 shortly after it made landfall. The image on the left is a combination of NOAA GOES and NASA QuikScat data superimposed. The white cloud structure was produced using GOES data, while the colored arrows showing wind speed and direction were created using QuikScat data. Red and purple arrows show winds as high as 25 meters per second (56 miles per hour). (Note that QuikScat only measures winds over the ocean; units are given in meters per second.) The image on the right was created using data from the Microwave Imager (TMI) aboard NASA's Tropical Rainfall Measuring Mission (TRMM). That sensor has the ability to peer within a storm and detect rainfall, seen here as red and green blobs. The red blobs show higher rainfall rates (up to 2 inches per hour), and greens show lower rainfall rates (1 inch per hour). Scientists are using data from these sensors to study how hurricane form, and grow and diminish in intensity during their lifetimes. For more information, see Hurricanes: The Greatest Storms on Earth. QuikScat image by William Daffer, courtesy of NASA's Jet Propulsion Laboratory TRMM image by Tom Bridgman, Goddard SVS; data courtesy TRMM Science Team at NASA's Goddard Space Flight Center

Extreme Rainfall from Hurricane Harvey (2017): Intercomparisons of WRF Simulations and Polarimetric Radar Fields

NASA Astrophysics Data System (ADS)

Yang, L.; Smith, J. A.; Liu, M.; Baeck, M. L.; Chaney, M. M.; Su, Y.

2017-12-01

Hurricane Harvey made landfall on 25 August 2017 and produced more than a meter of rain during a four-day period over eastern Texas, making it the wettest tropical cyclone on record in the United States. Extreme rainfall from Harvey was predominantly related to the dynamics and structure of outer rain bands. In this study, we provide details of the extreme rainfall produced by Hurricane Harvey. The principal research questions that motivate this study are: (1) what are the key microphysical properties of extreme rainfall from landfalling tropical cyclones and (2) what are the capabilities and deficiencies of existing bulk microphysics parameterizations from the physical models in capturing them. Our analyses are centered on intercomparisons of high-resolution simulations using the Weather Research and Forecasting (WRF) model and polarimetric radar fields from KHGX (Houston, Texas) WSR-88D. The WRF simulations accurately capture the track and intensity of Hurricane Harvey. Multi-rainband structure and its key evolution features are also well represented in the simulations. Two microphysics parameterizations (WSM6 and WDM6) are tested in this study. Radar reflectivity and differential reflectivity fields simulated by the WRF model are compared with polarimetric radar observations. An important feature for the extreme rainfall from Hurricane Harvey is the sharp boundary of spatial rainfall accumulation along the coast (with torrential rainfall distributed over Houston and its surrounding inland areas). We will examine the role of land-sea contrasts in dictating storm structure and evolution from both WRF simulations and polarimetric radar fields. Implications for improving hurricane rainfall forecasts and estimates will be provided.

The Tropical Convective Spectrum. Part 1; Archetypal Vertical Structures

NASA Technical Reports Server (NTRS)

Boccippio, Dennis J.; Petersen, Walter A.; Cecil, Daniel J.

2005-01-01

A taxonomy of tropical convective and stratiform vertical structures is constructed through cluster analysis of 3 yr of Tropical Rainfall Measuring Mission (TRMM) "warm-season" (surface temperature greater than 10 C) precipitation radar (PR) vertical profiles, their surface rainfall, and associated radar-based classifiers (convective/ stratiform and brightband existence). Twenty-five archetypal profile types are identified, including nine convective types, eight stratiform types, two mixed types, and six anvil/fragment types (nonprecipitating anvils and sheared deep convective profiles). These profile types are then hierarchically clustered into 10 similar families, which can be further combined, providing an objective and physical reduction of the highly multivariate PR data space that retains vertical structure information. The taxonomy allows for description of any storm or local convective spectrum by the profile types or families. The analysis provides a quasi-independent corroboration of the TRMM 2A23 convective/ stratiform classification. The global frequency of occurrence and contribution to rainfall for the profile types are presented, demonstrating primary rainfall contribution by midlevel glaciated convection (27%) and similar depth decaying/stratiform stages (28%-31%). Profiles of these types exhibit similar 37- and 85-GHz passive microwave brightness temperatures but differ greatly in their frequency of occurrence and mean rain rates, underscoring the importance to passive microwave rain retrieval of convective/stratiform discrimination by other means, such as polarization or texture techniques, or incorporation of lightning observations. Close correspondence is found between deep convective profile frequency and annualized lightning production, and pixel-level lightning occurrence likelihood directly tracks the estimated mean ice water path within profile types.

Electrical and Hydrometeor Structure of Thunderstorms that produce Upward Lightning

NASA Astrophysics Data System (ADS)

dos Santos Souza, J. C.; Albrecht, R. I.; Lang, T. J.; Saba, M. M.; Warner, T. A.; Schumann, C.

2017-12-01

Upward lightning (UL) flashes at tall structures have been reported to be initiated by in-cloud branching of a parent positive cloud-to-ground (CG) or intracloud (IC) lightning during the decaying stages of thunderstorms, and associated with stratiform precipitation. This in-cloud branching of the parent CG lightning into lower layers of the stratiform precipitation, as well as other situational modes of UL triggering, are indicative of a lower charge center. The objective of this study is to determine the hydrometeor characteristics of thunderstorms that produce UL, especially at the lower layers of the stratiform region where the bidirectional leader of the parent CG or IC lightning propagates through. We investigated 17 thunderstorms that produced 56 UL flashes in São Paulo, SP, Brazil and 10 thunderstorms (27 UL) from the UPLIGHTS field experiment in Rapid City, SD, USA. We used polarimetric radar data and 3D lighting mapping or the combination of total (i.e., intracloud and cloud-to-ground) and cloud-to-ground lightning strokes data. The Hydrometeor Identification for the thunderstorms of this study consider the information from polarimetric variables ZH, ZDR, KDP and RHOHV to infer radar echoes into rain (light, medium, heavy), hail, dry snow, wet snow, ice crystals, graupel and rain-hail mixtures. Charge structure is inferred by the 3D very-high-frequency (VHF) Lightning Mapping Array by monitoring lightning propagation closely in time and space and constructing vertical histograms of VHF source density. The results of this research project are important to increase the understanding of the phenomenon, the storm evolution and the predictability of UL.

The disposition of snow caught by conifer crowns

Treesearch

Donald R. Satterlund; Harold F. Haupt

1970-01-01

Snow interception studies during the warm winters of 1966-1967 and 1967-1968 in northern Idaho revealed that Douglas fir and western white pine saplings caught about one third of the snow that fell in 22 storms. More than 80% of the snow initially caught in the crowns ultimately reached the ground being washed off by subsequent rain, falling by direct mass release, or...

Precipitation-snowmelt timing and snowmelt augmentation of large peak flow events, western Cascades, Oregon

Treesearch

Keith Jennings; Julia A. Jones

2015-01-01

This study tested multiple hydrologic mechanisms to explain snowpack dynamics in extreme rain-on-snow floods, which occur widely in the temperate and polar regions. We examined 26, 10 day large storm events over the period 1992–2012 in the H.J. Andrews Experimental Forest in western Oregon, using statistical analyses (regression, ANOVA, and wavelet coherence) of hourly...

KSC-2013-2815

NASA Image and Video Library

2013-06-17

CAPE CANAVERAL, Fla. -- An ominous storm cloud hovers over Launch Complex 39 at NASA's Kennedy Space Center in Florida. The massive, 525-foot-tall facility at left is the Vehicle Assembly Building. Florida summers are known for their dynamic weather patterns with the start of the Atlantic hurricane season and the onset of afternoon thunderstorms that bring with them heavy rain, frequent lightning and occasionally even tornadoes. Photo credit: NASA/Jim Grossmann

Earth Observations taken by the Expedition Seven crew

NASA Image and Video Library

2003-07-15

ISS007-E-10244 (15 July 2003) --- The Expedition 7 crew onboard the International Space Station (ISS) had a great seat from which to observe tropical storm Claudette as she turned into a hurricane and came ashore with high winds and heavy rains that drenched their Houston home base and other Texas areas. This digital image was recorded at 13:26:41 GMT, July 15, 2003.

Respiratory disease and particulate air pollution in Santiago Chile: Contribution of erosion particles from fine sediments

Treesearch

Pablo A. Garcia-Chevesich; Sergio Alvarado; Daniel G. Neary; Rodrigo Valdes; Juan Valdes; Juan Jose Aguirre; Marcelo Mena; Roberto Pizarro; Paolo Jofre; Mauricio Vera; Claudio Olivares

2014-01-01

Air pollution in Santiago is a serious problem every winter, causing thousands of cases of breathing problems within the population. With more than 6 million people and almost two million vehicles, this large city receives rainfall only during winters. Depending on the frequency of storms, statistics show that every time it rains, air quality improves for a couple of...

Colors after the Storms

NASA Image and Video Library

2015-10-26

Damaging heavy rains fell on South Carolina in the southeastern United States at the beginning of October 2015. Much of that water had, by mid October, flowed into the Atlantic Ocean bringing with it heavy loads of sediment, nutrients, and dissolved organic material. The above VIIRS image shows the runoff as it interacts with ocean currents on October 15, 2015. Credit: NASA/Goddard/SuomiNPP/VIIRS via NASA's OceanColor

When lightning strikes: bolting down the facts & fiction.

PubMed

Usatch, Ben

2009-04-01

MYTH: There's no danger from lightning until the rain starts. FACT: Lightning often precedes the storm by up to 10 miles. A reasonable guideline is the "30-30 rule," by which you count the seconds between the flash and the thunder. If the time span is less than 30 seconds, seek shelter. Additionally, wait a full 30 minutes from last lightning flash to resume outdoor activities.

Trading Space for Time in Design Storm Estimation Using Radar Data

NASA Astrophysics Data System (ADS)

Haberlandt, U.; Berndt, C.

2017-12-01

Intensity-duration-frequency (IDF) curves are frequently used for the derivation of design storms. These curves are usually estimated from rain gauges and are valid for extreme rainfall at local observed points. Two common problems are involved. Regionalization of rainfall statistics for unobserved locations and the use of areal reduction factors (ARF) for the adjustment to larger catchments are required. Weather radar data are available with large spatial coverage and high resolution in space and could be used for a direct derivation of areal design storms for any location and catchment size. However, one problem with radar data is the relatively short observation period for the estimation of extreme events. This study deals with the estimation of area-intensity-duration-frequency (AIDF) curves and areal-reduction-factors (ARF) directly from weather radar data. The main objective is to answer the question if it is possible to trade space for time in the estimation of both characteristics to compensate for the short radar observation periods. In addition, a stratification of the temporal sample according to annual temperature indices is tried to distinguish "colder" and "warmer" climate years. This might eventually show a way for predicting future changes in AIDF curves and ARFs. First, radar data are adjusted with rainfall observations from the daily station network. Thereafter, AIDF curves and ARFs are calculated for different spatial and temporal sample sizes. The AIDF and ARFs are compared regarding their temporal and spatial variability considering also the temperature conditions. In order to reduce spatial variability a grouping of locations according to their climatological and physiographical characteristics is carried out. The data used for this study cover about 20 years of observations from the radar device located near Hanover in Northern Germany and 500 non-recording rain gauges as well as a set of 8 recording rain gauges for validation. AIDF curves and ARFS are analyzed for rainfall durations from 5 minutes to 24 hours and return periods from 1 year to 30 years. It is hypothesized, that the spatial variability of AIDF and ARF characteristics decreases with increasing sample size, grouping and normalization and is finally comparable to temporal variability.

New generation of meteorology cameras

NASA Astrophysics Data System (ADS)

Janout, Petr; Blažek, Martin; Páta, Petr

2017-12-01

A new generation of the WILLIAM (WIde-field aLL-sky Image Analyzing Monitoring system) camera includes new features such as monitoring of rain and storm clouds during the day observation. Development of the new generation of weather monitoring cameras responds to the demand for monitoring of sudden weather changes. However, new WILLIAM cameras are ready to process acquired image data immediately, release warning against sudden torrential rains, and send it to user's cell phone and email. Actual weather conditions are determined from image data, and results of image processing are complemented by data from sensors of temperature, humidity, and atmospheric pressure. In this paper, we present the architecture, image data processing algorithms of mentioned monitoring camera and spatially-variant model of imaging system aberrations based on Zernike polynomials.

Surface-water hydrologic data for the Houston metropolitan area, Texas, water years 1990-95

USGS Publications Warehouse

Sneck-Fahrer, Debra A.; Liscum, Fred; East, Jeffery W.

2003-01-01

During water years 1990–95, data were collected at 24 U.S. Geological Survey streamflow-gaging stations, 21 rain gages, and 6 water-quality stations in the Houston metropolitan area, Texas. The data were collected as part of the Houston Urban Runoff Program, which began in water year 1964. Annual peaks were defined for the 24 streamflow-gaging stations in the study area. All stations had 10 or more years of record. Precipitation data from the 21 rain gages and discharge or stage data from 23 streamflow-gaging stations are available to develop storm hydrographs. One-hundred thirty-four samples were collected at six water-quality stations. The samples were analyzed for about 80 water-quality properties and constituents.

Annual monsoon rains recorded by Jurassic dunes.

PubMed

Loope, D B; Rowe, C M; Joeckel, R M

2001-07-05

Pangaea, the largest landmass in the Earth's history, was nearly bisected by the Equator during the late Palaeozoic and early Mesozoic eras. Modelling experiments and stratigraphic studies have suggested that the supercontinent generated a monsoonal atmospheric circulation that led to extreme seasonality, but direct evidence for annual rainfall periodicity has been lacking. In the Mesozoic era, about 190 million years ago, thick deposits of wind-blown sand accumulated in dunes of a vast, low-latitude desert at Pangaea's western margin. These deposits are now situated in the southwestern USA. Here we analyse slump masses in the annual depositional cycles within these deposits, which have been described for some outcrops of the Navajo Sandstone. Twenty-four slumps, which were generated by heavy rainfall, appear within one interval representing 36 years of dune migration. We interpret the positions of 20 of these masses to indicate slumping during summer monsoon rains, with the other four having been the result of winter storms. The slumped lee faces of these Jurassic dunes therefore represent a prehistoric record of yearly rain events.

Observations of C-Band Brightness Temperatures and Ocean Surface Wind Speed and Rain Rate from the Hurricane Imaging Radiometer (HIRAD) during GRIP and HS3

NASA Technical Reports Server (NTRS)

Miller, Timothy L.; James, M. W.; Roberts, J. B.; Biswas, S.; Jones, W. L.; Johnson, J.; Farrar, S.; Ruf, C. S.; Uhlhorn, E. W.; Atlas, R.;

A new Grid Product of Tropical Cyclone Precipitation (TCP) for North America from 1930 to 2013

NASA Astrophysics Data System (ADS)

Zhu, L.

2015-12-01

We first developed a new method that collects daily TCP by using historical storm tracks and precipitation observation based on daily rain gauges in both U.S. and Mexico and calibrated it with satellite precipitation observation. We used a parametrized wind field to correct the possible under-estimations of precipitation in rain gauges. Grid interpolation parameters were optimized by testing different historical rain gauge densities and comparing our grid estimation of TCP and the observation from TRMM Multi-satellite Precipitation Analysis (3B42) by for the data available period from 1998 to 2013. The calibrated method was then used for the whole 94 years of TCP estimation. The preliminary result shows that the frequency of TCP events does not have significant change but the TCP intensity has significant increasing trends, especially in certain locations in North Carolina and Yucatan Peninsula in Mexico. This new long term TCP climatology can potentially assist model calibration and disaster prevention/mitigation.

Floods of June 1965 in South Platte River basin, Colorado

USGS Publications Warehouse

Matthai, Howard Frederick

1969-01-01

Heavy, intense rains in three areas on three different days caused outstanding floods on many streams in the South Platte River basin from Plum Creek, just south of Denver, downstream to the Colorado-Nebraska State line. The flood-producing storms followed a relatively wet period, and rainfall of as much as 14 inches in a few hours was reported. The storms occurred over the Greeley-Sterling area on June 14-15, over the Plum Creek and Cherry Creek basins on June 16, and over the headwaters of Kiowa and Bijou Creeks on June 17 after heavy rains on June 15. The flood crest did not pass Julesburg, in the northeast corner of Colorado, until June 20. Previous record high discharges on many tributaries with drainage areas on the plains were exceeded, sometimes severalfold. The six principal tributaries carrying snowmelt runoff were contributing, but not significant, factors in the floods. The attenuation of the peak flow by channel storage as the flood passed through Denver was considerable; yet the peak discharge of 40,300 cfs (cubic feet per second) of the South Platte River at Denver was 1.8 times the previously recorded high of 22,000 cfs in a period of record starting in 1889. The 1965 peak would have been still higher except that all flow from Cherry Creek was stored in Cherry Creek Reservoir. Six persons were drowned, and two other deaths were attributed to the storms. The total damage amounted to $508.2 million, and about 75 percent of this occurred in the Denver metropolitan area. Descriptions of the storms and floods, detailed streamflow records, and information on damages, flood profiles, inundated areas, and flood frequency are included in this report. Several comparisons of the magnitude of the flood are made, and all indicate that an outstanding hydrologic event occurred.

Return period curves for extreme 5-min rainfall amounts at the Barcelona urban network

NASA Astrophysics Data System (ADS)

Lana, X.; Casas-Castillo, M. C.; Serra, C.; Rodríguez-Solà, R.; Redaño, A.; Burgueño, A.; Martínez, M. D.

2018-03-01

Heavy rainfall episodes are relatively common in the conurbation of Barcelona and neighbouring cities (NE Spain), usually due to storms generated by convective phenomena in summer and eastern and south-eastern advections in autumn. Prevention of local flood episodes and right design of urban drainage have to take into account the rainfall intensity spread instead of a simple evaluation of daily rainfall amounts. The database comes from 5-min rain amounts recorded by tipping buckets in the Barcelona urban network along the years 1994-2009. From these data, extreme 5-min rain amounts are selected applying the peaks-over-threshold method for thresholds derived from both 95% percentile and the mean excess plot. The return period curves are derived from their statistical distribution for every gauge, describing with detail expected extreme 5-min rain amounts across the urban network. These curves are compared with those derived from annual extreme time series. In this way, areas in Barcelona submitted to different levels of flood risk from the point of view of rainfall intensity are detected. Additionally, global time trends on extreme 5-min rain amounts are quantified for the whole network and found as not statistically significant.

Improvement of Storm Forecasts Using Gridded Bayesian Linear Regression for Northeast United States

NASA Astrophysics Data System (ADS)

Yang, J.; Astitha, M.; Schwartz, C. S.

2017-12-01

Bayesian linear regression (BLR) is a post-processing technique in which regression coefficients are derived and used to correct raw forecasts based on pairs of observation-model values. This study presents the development and application of a gridded Bayesian linear regression (GBLR) as a new post-processing technique to improve numerical weather prediction (NWP) of rain and wind storm forecasts over northeast United States. Ten controlled variables produced from ten ensemble members of the National Center for Atmospheric Research (NCAR) real-time prediction system are used for a GBLR model. In the GBLR framework, leave-one-storm-out cross-validation is utilized to study the performances of the post-processing technique in a database composed of 92 storms. To estimate the regression coefficients of the GBLR, optimization procedures that minimize the systematic and random error of predicted atmospheric variables (wind speed, precipitation, etc.) are implemented for the modeled-observed pairs of training storms. The regression coefficients calculated for meteorological stations of the National Weather Service are interpolated back to the model domain. An analysis of forecast improvements based on error reductions during the storms will demonstrate the value of GBLR approach. This presentation will also illustrate how the variances are optimized for the training partition in GBLR and discuss the verification strategy for grid points where no observations are available. The new post-processing technique is successful in improving wind speed and precipitation storm forecasts using past event-based data and has the potential to be implemented in real-time.

Study of Extreme Weather Hazards Using GRACE

NASA Astrophysics Data System (ADS)

Zhang, Y.; Shum, C. K.; Shang, K.; Guo, J.; Schwartz, F. W.; Akyılmaz, O.; Feng, W.; Forootan, E.; LIU, G.; Zhong, M.

2017-12-01

Extreme weather events significantly affect humans and economics in the region. Synoptic and timely observations of these abrupt meteoro-hydrological hazards would benefit disaster management and improve storm forecasting. Contemporary processing of the Gravity Recovery and Climate Experiment (GRACE) twin-satellite data at monthly sampling would miss or under-sample abrupt events such as large ice storms with durations much shorter than a month. Here, we employ the energy balance approach processing GRACE Level 1 data, which is flexible to allow sub-monthly solutions at daily sampling covering the genesis and evolution of large winter storms. We studied the 2008 Southeast China snow and ice storm, which lasted from mid-January to mid-February, and affected 21 out of China's 34 provinces with heavy snows, ice and freezing rains, caused extensive damage and transportation disruption, displaced nearly 1.7 million people, and claimed 129 lives. We also investigated the devastating North America blizzard which occurred during late January through mid-February 2010. The massive accumulations of snow and ice in both storms slightly changed the gravity field of the Earth, and were sensitive to the GRACE satellite measurements, manifested as transient terrestrial water storage (TWS) change. We compared our solutions with other available high temporal frequency GRACE solutions. The GRACE observed total storage change for both storms are in good agreement with in situ precipitation measurements, and with GRACE observations clearly show the complex genesis, decline, strengthening and melting phases depicting the detailed evolution of these example large snow storms.

Mitigating the health impacts of a natural disaster--the June 2007 long-weekend storm in the Hunter region of New South Wales.

PubMed

Cretikos, Michelle A; Merritt, Tony D; Main, Kelly; Eastwood, Keith; Winn, Linda; Moran, Lucille; Durrheim, David N

A severe storm that began on Thursday, 7 June 2007 brought heavy rains and gale-force winds to Newcastle, Gosford, Wyong, Sydney, and the Hunter Valley region of New South Wales. The storm caused widespread flooding and damage to houses, businesses, schools and health care facilities, and damaged critical infrastructure. Ten people died as a result of the storm, and approximately 6000 residents were evacuated. A natural disaster was declared in 19 local government areas, with damage expected to reach $1.5 billion. Additional demands were made on clinical health services, and interruption of the electricity supply to over 200,000 homes and businesses, interruption of water and gas supplies, and sewerage system pump failures presented substantial public health threats. A public health emergency operations centre was established by the Hunter New England Area Health Service to coordinate surveillance activities, respond to acute public health issues and prevent disease outbreaks. Public health activities focused on providing advice, cooperating with emergency service agencies, monitoring water quality and availability, preventing illness from sewage-contaminated flood water, assessing environmental health risks, coordinating the local government public health response, and surveillance for storm-related illness and disease outbreaks, including gastroenteritis. The local ABC (Australian Broadcasting Corporation) radio station played a key role in disseminating public health advice. A household survey conducted within a fortnight of the storm established that household preparedness and storm warning systems could be improved.

Physical aspects of Hurricane Hugo in Puerto Rico

USGS Publications Warehouse

Scatena, F.N.; Larsen, Matthew C.

1991-01-01

On 18 September 1989 the western part ofHurricane Hugo crossed eastern Puerto Rico and the Luquillo Experimental Forest (LEF). Storm-facing slopes on the northeastern part of the island that were within 15 km of the eye and received greater than 200 mm of rain were most affected by the storm. In the LEF and nearby area, recurrence intervals associated with Hurricane Hugo were 50 yr for wind velocity, 10 to 31 yr for stream discharge, and 5 yr for rainfall intensity. To compare the magnitudes of the six hurricanes to pass over PuertoRico since 1899, 3 indices were developed using the standardized values of the product of: the maximum sustained wind speed at San Juan squared and storm duration; the square of the product of the maximum sustained wind velocity at San Juan and the ratio of the distance between the hurricane eye and San Juan to the distance between the eye and percentage of average annual rainfall delivered by the storm. Based on these indices, HurricaneHugo was of moderate intensity. However, because of the path of Hurricane Hugo, only one of these six storms (the 1932 storm) caused more damage to the LEF than Hurricane Hugo. Hurricanes of Hugo's magnitude are estimated to pass over the LEF once every 50-60 yr, on average. 

Effect of storm events on riverine nitrogen dynamics in a subtropical watershed, southeastern China.

PubMed

Chen, Nengwang; Wu, Jiezhong; Hong, Huasheng

2012-08-01

Rain storms are predicted to increase in the subtropical region due to climate change. However, the effects of storm events on riverine nitrogen (N) dynamics are poorly understood. In this study, the riverine N dynamics and storm effects in a large subtropical river (North Jiulong River, southeastern China) were investigated through continuous sampling of two storm events which occurred in June 2010 and June 2011. The results disclosed a strong linkage between N dynamics and hydrological controls and watershed characteristics. The extreme storm in June 2010 resulted in more fluctuations in N concentrations, loads, and composition, compared with the moderate storm in June 2011. There were contrasting patterns (e.g., the hysteresis effect) between nitrate and ammonium behavior in storm runoff, reflecting their different supply source and transport mechanism. Overall, nitrate supply originated from subsurface runoff and was dominated by within-channel mobilization, while ammonium was mainly from over-land sources and flushed by surface runoff. Extreme storm runoff (2010) caused a four-fold increase in dissolved inorganic N fluxes (DIN), with a greater fraction of ammonium (up to 30% of DIN) compared with the moderate storm and background flow condition (less than 15%). Storm-driven sharp increases of N loads and changes in nutrient stoichiometry (more ammonium) might have been connected with algal blooms in the adjacent estuary and Xiamen Bay. Combined with the background flow measurement of N gradients along the main river and a stream together with anthropogenic N load information, the interactive effect of hydrological and biogeochemical process on riverine N was preliminarily revealed. Current results suggested that storm runoff N was controlled by rainfall, hydrological condition, antecedent soil moisture, spatial variability of land-based N source, and damming. These findings could be used as a reference for future water quality monitoring programs and the development of a pollution mitigation strategy. Copyright © 2012 Elsevier B.V. All rights reserved.

Modeling urban flood risk territories for Riga city

NASA Astrophysics Data System (ADS)

Piliksere, A.; Sennikovs, J.; Virbulis, J.; Bethers, U.; Bethers, P.; Valainis, A.

2012-04-01

Riga, the capital of Latvia, is located on River Daugava at the Gulf of Riga. The main flooding risks of Riga city are: (1) storm caused water setup in South part of Gulf of Riga (storm event), (2) water level increase caused by Daugava River discharge maximums (spring snow melting event) and (3) strong rainfall or rapid snow melting in densely populated urban areas. The first two flooding factors were discussed previously (Piliksere et al, 2011). The aims of the study were (1) the identification of the flood risk situations in densely populated areas, (2) the quantification of the flooding scenarios caused by rain and snow melting events of different return periods nowadays, in the near future (2021-2050), far future (2071-2100) taking into account the projections of climate change, (3) estimation of groundwater level for Riga city, (4) the building and calibration of the hydrological mathematical model based on SWMM (EPA, 2004) for the domain potentially vulnerable for rain and snow melt flooding events, (5) the calculation of rain and snow melting flood events with different return periods, (6) mapping the potentially flooded areas on a fine grid. The time series of short term precipitation events during warm time period of year (id est. rain events) were analyzed for 35 year long time period. Annual maxima of precipitation intensity for events with different duration (5 min; 15 min; 1h; 3h; 6h; 12h; 1 day; 2 days; 4 days; 10 days) were calculated. The time series of long term simultaneous precipitation data and observations of the reduction of thickness of snow cover were analyzed for 27 year long time period. Snow thawing periods were detected and maximum of snow melting intensity for events with different intensity (1day; 2 days; 4 days; 7 days; 10 days) were calculated. According to the occurrence probability six scenarios for each event for nowadays, near and far future with return period once in 5, 10, 20, 50, 100 and 200 years were constructed based on the Gumbell extreme value analysis. The hydrological modelling driven by the temperature and precipitation data series from regional climate models were used for evaluation of rain event maximums in the future periods. The usage of the climate model data in hydrological models causes systematic errors; therefore the bias correction method (Sennikovs, Bethers, 2009) was applied for determination of the future rainfall intensities. SWMM model was built for the urban area. Objects of hydraulic importance (manifold, penstock, ditch, pumping station, weir, well, catchment sub-basin etc.) were included in the model. There exist pure rain sewage system and mixed rain-water/household sewage system in Riga. Sewage system with wastewater load proportional to population density was taken account and calibrated. Model system was calibrated for a real rain event against the water flux time series into sewage treatment plant of Riga. High resolution (~1.5 points per square meter) digital terrain map was used as the base for finite element mesh for the geospatial mapping of results of hydraulic calculations. Main results of study are (1) detection of the hot spots of densely populated urban areas; (2) identification of the weak chains of the melioration and sewage systems; (3) mapping the elevation of ground water mainly caused by snow melting. A.Piliksere, A.Valainis, J.Seņņikovs, (2011), A flood risk assessment for Riga city taking account climate changes, EGU, Vienna, Austria. EPA, (2004), Storm water management model. User's manual version 5.0. US Environmental Protection Agency J.Sennikovs, U.Bethers, (2009), Statistical downscaling method of regional climate model results for hydrological modelling. 18th World IMACS/MODSIM Congress, Cairns, Australia.

Relationship between convective precipitation and lightning activity using radar quantitative precipitation estimates and total lightning data

NASA Astrophysics Data System (ADS)

Pineda, N.; Rigo, T.; Bech, J.; Argemí, O.

2009-09-01

Thunderstorms can be characterized by both rainfall and lightning. The relationship between convective precipitation and lightning activity may be used as an indicator of the rainfall regime. Besides, a better knowledge of local thunderstorm phenomenology can be very useful to assess weather surveillance tasks. Two types of approach can be distinguished in the bibliography when analyzing the rainfall and lightning activity. On one hand, rain yields (ratio of rain mass to cloud-to-ground flash over a common area) calculated for long temporal and spatial domains and using rain-gauge records to estimate the amounts of precipitation. On the other hand, a case-by-case approach has been used in many studies to analyze the relationship between convective precipitation and lightning in individual storms, using weather radar data to estimate rainfall volumes. Considering a local thunderstorm case study approach, the relation between rainfall and lightning is usually quantified as the Rainfall-Lightning ratio (RLR). This ratio estimates the convective rainfall volume per lightning flash. Intense storms tend to produce lower RLR values than moderate storms, but the range of RLR found in diverse studies is quite wide. This relationship depends on thunderstorm type, local climatology, convective regime, type of lightning flashes considered, oceanic and continental storms, etc. The objective of this paper is to analyze the relationship between convective precipitation and lightning in a case-by-case approach, by means of daily radar-derived quantitative precipitation estimates (QPE) and total lightning data, obtained from observations of the Servei Meteorològic de Catalunya remote sensing systems, which covers an area of approximately 50000 km2 in the NE of the Iberian Peninsula. The analyzed dataset is composed by 45 thunderstorm days from April to October 2008. A good daily correlation has been found between the radar QPE and the CG flash counts (best linear fit with a R^2=0.74). The daily RLR found has a mean value of 86 10^3m3 rainfall volume per CG flash. The daily range of variation is quite wide, as it goes from 19 to 222 10^3m3 per CG flash. This variation has a seasonal component, related to changes in the convective regime. Summer days (July to middle September) had a mean RLR of 57 10^3m3 rainfall volume per CG flash, while from middle September to the end of October the rainfall volume per CG flash doubles (mean of 125 10^3m3 per CG flash).

Spatial and temporal features of heavy rainstorm events in Calabria, Southern Italy

NASA Astrophysics Data System (ADS)

Terranova, Oreste Giuseppe; Gariano, Stefano Luigi; Greco, Raffaele

2015-04-01

Heavy rainstorms often induce flash floods, shallow landslides and debris flows, which cause several damage to manmade infrastructures and loss of lives. The analysis of spatial distribution and temporal features of intense rainfall events is a fundamental step for a better understanding of the phenomena and for its possible prediction. The present study is an attempt to improve, from a statistical point of view, the understanding at sub-hourly scale of the temporal and spatial structure of intense rainfall events, by examining those that have hit Calabria (Southern Italy) in the years 1998-2008. More in detail, a considerable amount of series with high temporal detail (5 min) related to 155 sites (one rain gauge per less than 100 sq km), were analysed. First, more than 152 thousands rainfall events, separated by at least 6 hours of dry weather, were recognized. Then, less than a third (45,533) were selected, since denoted as erosive. Finally, several heavy rainstorm events (HREs) were chosen by considering the rainfall events recorded simultaneously at different rain gauges, even non-contiguous, within the region. In particular, this further selection was conducted, based on heuristic threshold values of cumulated rainfall (≥ 100 mm), maximum intensity (≥ 50 mm/h), and kinetic energy (≥ 29 MJ/ha). Therefore, 25 distinct HREs, including all the well-known catastrophic geo-hydrological events, were subjected to thorough investigation. The obtained HREs, automatically classified according to their structure in time, were analysed as regards both spatial and temporal evolution. At this end, the 25 HREs were distinguished as widespread (17) or localized (8), if the affected area is ≥ 500 sq km or < 500 sq km, respectively. In particular, the temporal storm structure was described by means of the standardized rainfall profile (rainfall amount vs. duration, in terms on cumulative percentages). Then, a 4-digit binary shape code was adopted to automatically identify the shape of the profile (Terranova and Iaquinta, 2011; Terranova and Gariano, 2014). HREs have different spatial extents and temporal patterns. A wide spatial extent of the events does not imply damage proportionally high. Generally, a peak at the beginning of the event (thunderstorm-type) characterizes localized events. On the contrary, widespread events present mixed temporal structures with peaks localized in the last half of their duration. The proposed method improves the knowledge regarding the input of rainfall-runoff watershed models. These models can benefit from design storms, based on the synthesis of recorded rainstorms, having a time structure integrated with the results of the spatial analysis. The notable size of the employed sample, including data with a very detailed time resolution that relate to several rain gauges well distributed throughout the region, gives robustness to the obtained results. References O.G. Terranova, and P. Iaquinta.: Temporal properties of rainfall events in Calabria (southern Italy). Nat. Hazards Earth Syst. Sci., 11, 751-757, 2011. O.G. Terranova, and S.L. Gariano.: Rainstorms able to induce flash floods in a Mediterranean-climate region (Calabria, southern Italy). Nat. Hazards Earth Syst. Sci., 14, 2423-2434, 2014.

A real-time control strategy for separation of highly polluted storm water based on UV-Vis online measurements--from theory to operation.

PubMed

Hoppe, H; Messmann, S; Giga, A; Gruening, H

2011-01-01

'Classical' real-time control (RTC) strategies in sewer systems are based on water level and flow measurements with the goal of activation of retention volume. The control system rule of 'clean (storm water) runoff into the receiving water - polluted runoff into the treatment plant' has been thwarted by rough operating conditions and lack of measurements. Due to the specific boundary conditions in the city of Wuppertal's separate sewer system (clean stream water is mixed with polluted storm water runoff) a more sophisticated--pollution-based--approach was needed. In addition the requirements to be met by the treatment of storm water runoff have become more stringent in recent years. To separate the highly-polluted storm water runoff during rain events from the cleaner stream flow a pollution-based real-time control (P-RTC) system was developed and installed. This paper describes the measurement and P-RTC equipment, the definition of total suspended solids as the pollution-indicating parameter, the serviceability of the system, and also gives a cost assessment. A sensitivity analysis and pollution load calculations have been carried out in order to improve the P-RTC algorithm. An examination of actual measurements clearly shows the ecological and economic advantages of the P-RTC strategy.

Uncertainties on the definition of critical rainfall patterns for debris-flows triggering. Results from the Rebaixader monitoring site (Central Pyrenees)

NASA Astrophysics Data System (ADS)

Hürlimann, Marcel; Abancó, Clàudia; Moya, Jose; Berenguer, Marc

2015-04-01

Empirical rainfall thresholds are a widespread technique in debris-flow hazard assessment and can be established by statistical analysis of historic data. Typically, data from one or several rain gauges located nearby the affected catchment is used to define the triggering conditions. However, this procedure has been demonstrated not to be accurate enough due to the spatial variability of convective rainstorms. In 2009, a monitoring system was installed in the Rebaixader catchment, Central Pyrenees (Spain). Since then, 28 torrential flows (debris flows and debris floods) have occurred and rainfall data of 25 of them are available with a 5-minutes frequency of recording ("event rainfalls"). Other 142 rainfalls that did not trigger events ("no event rainfalls) were also collected and analysed. The goal of this work was threefold: a) characterize rainfall episodes in the Rebaixader catchment and compare rainfall data that triggered torrential events and others that did not; b) define and test Intensity-Duration (ID) thresholds using rainfall data measured inside the catchment; c) estimate the uncertainty derived from the use of rain gauges located outside the catchment based on the spatial correlation depicted by radar rainfall maps. The results of the statistical analysis showed that the parameters that more distinguish between the two populations of rainfalls are the rainfall intensities, the mean rainfall and the total precipitation. On the other side, the storm duration and the antecedent rainfall are not significantly different between "event rainfalls" and "no event rainfalls". Four different ID rainfall thresholds were derived based on the dataset of the first 5 years and tested using the 2014 dataset. The results of the test indicated that the threshold corresponding to the 90% percentile showed the best performance. Weather radar data was used to analyse the spatial variability of the triggering rainfalls. The analysis indicates that rain gauges outside the catchment may be considered useful or not to describe the rainfall depending on the type of rainfall. For widespread rainfalls, further rain gauges can give a reliable measurement, because the spatial correlation decreases slowly with the distance between the rain gauge and the debris-flow initiation area. Contrarily, local storm cells show higher space-time variability and, therefore, representative rainfall measurements are obtained only by the closest rain gauges. In conclusion, the definition of rainfall thresholds is a delicate task. When the rainfall records are coming from gauges that are outside the catchment under consideration, the data should be carefully analysed and crosschecked with radar data (especially for small convective cells).

The impact of a prominent rain shadow on flooding in California's Santa Cruz Mountains: A CALJET case study and sensitivity to the ENSO cycle

USGS Publications Warehouse

Ralph, F.M.; Neiman, P.J.; Kingsmill, D.E.; Persson, P.O.G.; White, A.B.; Strem, E.T.; Andrews, E.D.; Antweiler, Ronald C.

2003-01-01

Data from the California Land-Falling Jets Experiment (CALJET) are used to explore the causes of variations in flood severity in adjacent coastal watersheds within the Santa Cruz Mountains on 2-3 February 1998. While Pescadero Creek (rural) experienced its flood of record, the adjacent San Lorenzo Creek (heavily populated), attained only its fourth-highest flow. This difference resulted from conditions present while the warm sector of the storm, with its associated low-level jet, high moisture content, and weak static stability, was overhead. Rainfall in the warm sector was dominated by orographic forcing. While the wind speed strongly modulated rain rates on windward slopes, the wind direction positioned the edge of a rain shadow cast by the Santa Lucia Mountains partially over the San Lorenzo basin, thus protecting the city of Santa Cruz from a more severe flood. Roughly 26% ?? 9% of the streamflow at flood peak on Pescadero Creek resulted from the warm-sector rainfall. Without this rainfall, the peak flow on Pescadero Creek would likely not have attained record status. These results are complemented by a climatological analysis based on ???50-yr-duration streamflow records for these and two other nearby windward watersheds situated ???20 to 40 km farther to the east, and a comparison of this climatological analysis with composites of NCEP-NCAR reanalysis fields. The westernmost watersheds were found to have their greatest floods during El Nin??o winters, while the easternmost watersheds peaked during non-El Nin??o episodes. These results are consistent with the case study, that showed that the composite 925-mb, meridionally oriented wind direction during El Nin??os favors a rain shadow over the eastern watersheds. During non-El Nin??o periods, the composite, zonally oriented wind direction indicates that the sheltering effect of the rain shadow on the eastern watersheds is reduced, while weaker winds, less water vapor, and stronger stratification reduce the peak runoff in the western watersheds relative to El Nin??o periods. These case study and climatological results illustrate the importance of conditions in the moisture-rich warm sector of landfalling Pacific winter storms. Although many other variables can influence flooding, this study shows that variations of ??10?? in wind direction can modulate the location of orographically enhanced floods. While terrain can increase predictability (e.g., rainfall typically increases with altitude), the predictability is reduced when conditions are near a threshold separating different regimes (e.g., in or out of a rain shadow ).

Changing character of rainfall in eastern China, 1951-2007.

PubMed

Day, Jesse A; Fung, Inez; Liu, Weihan

2018-02-27

The topography and continental configuration of East Asia favor the year-round existence of storm tracks that extend thousands of kilometers from China into the northwestern Pacific Ocean, producing zonally elongated patterns of rainfall that we call "frontal rain events." In spring and early summer (known as "Meiyu Season"), frontal rainfall intensifies and shifts northward during a series of stages collectively known as the East Asian summer monsoon. Using a technique called the Frontal Rain Event Detection Algorithm, we create a daily catalog of all frontal rain events in east China during 1951-2007, quantify their attributes, and classify all rainfall on each day as either frontal, resulting from large-scale convergence, or nonfrontal, produced by local buoyancy, topography, or typhoons. Our climatology shows that the East Asian summer monsoon consists of a series of coupled changes in frontal rain event frequency, latitude, and daily accumulation. Furthermore, decadal changes in the amount and distribution of rainfall in east China are overwhelmingly due to changes in frontal rainfall. We attribute the "South Flood-North Drought" pattern observed beginning in the 1980s to changes in the frequency of frontal rain events, while the years 1994-2007 witnessed an uptick in event daily accumulation relative to the rest of the study years. This particular signature may reflect the relative impacts of global warming, aerosol loading, and natural variability on regional rainfall, potentially via shifting the East Asian jet stream.

Comparison of storm response of streams in small, unmined and valley-filled watersheds, 1999-2001, Ballard fork, West Virginia

USGS Publications Warehouse

Messinger, Terence

2003-01-01

During storms when rainfall intensity exceeded about 1 inch per hour, peak unit runoff from the Unnamed Tributary (surface-mined and filled) Watershed exceeded peak unit runoff from the Spring Branch (unmined) Watershed in the Ballard Fork Watershed in southern West Virginia. During most storms, those with intensity less than about 1 inch per hour, peak unit (area-normalized) flows were greater from the Spring Branch Watershed than the Unnamed Tributary Watershed. One storm that produced less than an inch of rain before flow from the previous storm had receded caused peak unit flow from the Unnamed Tributary Watershed to exceed peak unit flow from the Spring Branch Watershed. Peak unit flow was usually similar in Spring Branch and Ballard Fork. Peak unit flows are expected to decrease with increasing watershed size in homogeneous watersheds; drainage area and proportion of the three watersheds covered by valley fills are 0.19 square mile (mi?) and 44 percent for the Unnamed Tributary Watershed, 0.53 mi? and 0 percent for the Spring Branch Watershed, and 2.12 mi? and 12 percent for the Ballard Fork Watershed. Following all storms with sufficient rainfall intensity, about 0.25 inches per hour, the storm hydrograph from the Unnamed Tributary Watershed showed a double peak, as a sharp initial rise was followed by a decrease in flow and then a delayed secondary peak of water that had apparently flowed through the valley fill. Hortonian (excess overland) flow may be important in the Unnamed Tributary Watershed during intense storms, and may cause the initial peak on the rising arm of storm hydrographs; the water composing the initial peaks may be conveyed by drainage structures on the mine. Ballard Fork and Spring Branch had hydrographs with single peaks, typical of elsewhere in West Virginia. During all storms with 1-hour rainfall greater than 0.75 inches or 24-hour rainfall greater than 1.75 inches during which all stream gages recorded a complete record, the Unnamed Tributary yielded the most total unit flow. In three selected major storms, total unit flow from the Unnamed Tributary during recessions exceeded storm flow, and its total unit flow was greatest among the streams during all three recessions. Runoff patterns from the mined watershed are influenced by the compaction of soils on the mine, the apparent low maximum rate of infiltration into the valley fill compared to that in the unmined, forested watershed, storage of water in the valley fill, and the absence of interception from trees and leaf litter. No storms during this study produced 1-hour or 24-hour rainfall in excess of the 5-year return period, and streamflow during this study never exceeded a magnitude equivalent to the 1.5-year return period; relative peak unit flow among the three streams in this study could be different in larger storms. Rainfall-runoff relations on altered landscapes are site-specific, and aspects of mining and reclamation practice that affect storm response may vary among mines.

A cold air outbreak over the Norwegian Sea observed with the Tiros-N Operational Vertical Sounder (TOVS) and the Special Sensor Microwave/Imager (SSM/I)

NASA Technical Reports Server (NTRS)

Claud, Chantal; Katsaros, Kristina B.; Petty, Grant W.; Chedin, Alain; Scott, Noelle A.

1992-01-01

Until recently, the scarcity of meteorological observations over polar areas has limited studies of high-latitude weather systems, but now data from polar orbiting satellites offer a new opportunity to observe and describe these systems. TOVS data have been used successfully for delineating synoptic and subsynoptic systems, since they provide the vertical temperature structure of the atmosphere; SSM/I observations have proved valuable for analyzing storms through water vapor and rain determinations. These positive results prompted simultaneous analysis of TOVS and SSM/I observations obtained during a cold air outbreak over the Norwegian Sea. After a description of the instruments and the retrieval schemes, the mutually supporting information from these two independent instruments is discussed. Implications for the monitoring of polar lows are presented.

A cold air outbreak over the Norwegian Sea observed with the Tiros-N Operational Vertical Sounder (TOVS) and the Special Sensor Microwave/Imager (SSM/I)

NASA Technical Reports Server (NTRS)

Claud, Chantal; Katsaros, Kristina B.; Petty, Grant W.; Chedin, Alain; Scott, Noelle A.

1992-01-01

Until recently, the scarcity of meteorological observations over polar areas has limited studies of high latitude weather systems, but now data from polar orbiting satellites offer a new opportunity to observe and describe these systems. TOVS data were used successfully for delineating synoptic and subsynoptic systems since they provide the vertical temperature structure of the atmosphere: SSM/I observations have proved valuable for analyzing storms through water vapor and rain determinations. These positive results prompted us to analyze simultaneous TOVS and SSM/I observations obtained during a cold air outbreak over the Norwegian Sea. After a description of the instruments and the retrieval schemes, the mutually supporting information from these two independent instruments is discussed. Implications for the monitoring of polar lows are presented.

Convective Radio Occultations Final Campaign Summary

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

Biondi, R.

2016-03-01

Deep convective systems are destructive weather phenomena that annually cause many deaths and injuries as well as much damage, thereby accounting for major economic losses in several countries. The number and intensity of such phenomena have increased over the last decades in some areas of the globe. Damage is mostly caused by strong winds and heavy rain parameters that are strongly connected to the structure of the particular storm. Convection over land is usually stronger and deeper than over the ocean and some convective systems, known as supercells, also develop tornadoes through processes that remain mostly unclear. The intensity forecastmore » and monitoring of convective systems is one of the major challenges for meteorology because in situ measurements during extreme events are too sparse or unreliable and most ongoing satellite missions do not provide suitable time/space coverage.« less

Atmospheric surface and boundary layers of the Amazon Basin

NASA Technical Reports Server (NTRS)

Garstang, Michael

1987-01-01

Three phases of work were performed: design of and preparation for the Amazon Boundary Layer Experiment (ABLE 2-A); execution of the ABLE 2-A field program; and analysis of the ABLE 2-A data. Three areas of experiment design were dealt with: surface based meteorological measurements; aircraft missions; and project meteorological support. The primary goal was to obtain a good description of the structure of the atmosphere immediately above the rain forest canopy (top of canopy to a few thousand meters), to describe this region during the growing daytime phase of the boundary layer; and to examine the nighttime stratified state. A secondary objective was to examine the role that deep convective storms play in the vertical transport of heat, water vapor, and other trace gases. While significant progress was made, much of the analysis remains to be done.

A Study on Feasibility of Dual-Wavelength Radar for Identification of Hydrometeor Phases

NASA Technical Reports Server (NTRS)

Liao, Liang; Meneghini, Robert

2010-01-01

An important objective for the Dual-wavelength Ku-/Ka-band Precipitation Radar (DPR) that will be on board the Global Precipitation Measuring (GPM) core satellite, is to identify the phase state of hydrometeors along the range direction. To assess this, radar signatures are simulated in snow and rain to explore the relation between the differential frequency ratio (DFR), defined as the difference of radar reflectivity factors between Ku- and Ka-bands, and the radar reflectivity factor at Ku-band, ZKu, for different hydrometeor types. Model simulations indicate that there is clear separation between snow and rain in the ZKu-DFR plane assuming that the snow follows the Gunn-Marshall size distribution (1958) and rain follows the Marshall-Palmer size distribution (1948). In an effort to verify the simulated results, the data collected by the Airborne Second Generation Precipitation Radar (APR-2) in the Wakasa Bay AMSR-E campaign are employed. Using the signatures of Linear Depolarization Ratio (LDR) at Ku-band, the APR-2 data can be easily divided into the regions of snow, mixed phase and rain for stratiform storms. These results are then superimposed onto the theoretical curves computed from the model in the ZKu-DFR plane. It has been found that in 90% of the cases, snow and rain can be distinguished if the Ku-band radar reflectivity exceeds 18 dBZ (the minimum detectable level of GPM DPR at Ku-band). This is also the case for snow and mixed-phase hydrometeors. Although snow can be easily distinguished from rain and melting hydrometeors by using Ku- and Ka-band radar, the rain and mixed-phase particles are not always separable. It is concluded that Ku- and Ka-band dual-wavelength radar might provide a potential means to identify the phase state of hydrometeors.

Advances in planetary geology

NASA Technical Reports Server (NTRS)

1983-01-01

Topics discussed include: (1) Martian global tectonics; (2) the origin and evolution of a circular and an irregular lunar mare; (3) stratigraphy of Oceanus Procellarum basalts: sources and styles of emplacement; (4) the tectonic evolution of the Oceanus Procellarum Basin; (5) charting the Southern Seas: the evolution of the Lunar Mare Australe; (6) the stratigraphy of Mare Imbrium; and (7) Storms and rains: a comparison of the Lunar Mare Imbrium and Oceanus Procellarum.

1975 Annual Typhoon Report

DTIC Science & Technology

1995-01-01

southwest monsoon. Tropical Cyclone 24-75 formed just off the southwest tip of the Indian subcontinent. 3X tracked northwest and dissipated over water ...Tropical Cyclone 33-75 formed in late November and described an erratic track in the southwest portion of the Bay. The storm dissipated over water ...Leyte leaving 15 dead rains were spawned over the caused widespread flooding Choppy waters near capsized a crowded motorboat and 30 missing. FIGURE 4

Modelling of green roofs' hydrologic performance using EPA's SWMM.

PubMed

Burszta-Adamiak, E; Mrowiec, M

2013-01-01

Green roofs significantly affect the increase in water retention and thus the management of rain water in urban areas. In Poland, as in many other European countries, excess rainwater resulting from snowmelt and heavy rainfall contributes to the development of local flooding in urban areas. Opportunities to reduce surface runoff and reduce flood risks are among the reasons why green roofs are more likely to be used also in this country. However, there are relatively few data on their in situ performance. In this study the storm water performance was simulated for the green roofs experimental plots using the Storm Water Management Model (SWMM) with Low Impact Development (LID) Controls module (version 5.0.022). The model consists of many parameters for a particular layer of green roofs but simulation results were unsatisfactory considering the hydrologic response of the green roofs. For the majority of the tested rain events, the Nash coefficient had negative values. It indicates a weak fit between observed and measured flow-rates. Therefore complexity of the LID module does not affect the increase of its accuracy. Further research at a technical scale is needed to determine the role of the green roof slope, vegetation cover and drying process during the inter-event periods.

Characterization of carbohydrates in rainwater from the southeastern North Carolina.

PubMed

Mullaugh, Katherine M; Byrd, Jade N; Avery, G Brooks; Mead, Ralph N; Willey, Joan D; Kieber, Robert J

2014-07-01

Carbohydrates have been widely reported in atmospheric aerosols, but have not previously been quantified in rainwater. We have identified and quantified a series of 11 specific compounds including monosaccharides (glucose, fructose, arabinose, galactose and pinitol), disaccharides (sucrose and trehalose), sugar alcohols (arabitol, dulcitol and mannitol) and the anhydrosaccharide levoglucosan. Rainwater analyzed in this study includes 52 distinct precipitation events in Wilmington, NC between June 2011 and October 2012. Our analysis indicates carbohydrates typically contribute <1% of total dissolved organic carbon in rain, but can account for as much as 10-35% during periods of high pollen or local fires. Concentrations of individual carbohydrates reached as high as 5.8 μM, with glucose and sucrose typically being the predominant species. The distribution of carbohydrates exhibited a distinct seasonal pattern, with higher concentrations of most carbohydrates, especially sucrose, in spring and summer, driven primarily by increased biogenic inputs during the growing season. Concentrations of carbohydrates were an order of magnitude higher in storms of terrestrial origin compared to marine events, further supporting a terrestrial biogenic origin of most species. Sequential sampling of Hurricane Irene showed significant quantities of carbohydrates present at the end of the storm when air mass back trajectories traversed over land. The highest level of levoglucosan, a compound associated with biomass burning, was detected in rain with an air mass back trajectory that traveled over a region affected by wildfires. When compared to aerosol concentrations reported by others, the sugar concentrations in rain demonstrate wet deposition is an important removal mechanism of this water-soluble and bioavailable fraction of atmospheric particulate organic matter. Copyright © 2014 Elsevier Ltd. All rights reserved.

Summary of floods in the United States during 1958

USGS Publications Warehouse

Hendricks, E.L.

1964-01-01

This report describes the most outstanding floods that occurred in the United States during 1958.A series of storms from January 23 to February 16 brought large amounts of precipitation to northern California and produced damaging floods, particularly in the Lower Sacramento Valley where losses totaled about \\$12 million.Major floods, notable because of the large area affected, occurred on many small streams in central and south Texas, following heavy general rains in late February. Extensive flooding occurred along the Gulf Coastal plain on the lower reaches of the major streams from the Brazos River to the Nueces River. Two lives were lost, and property damage exceeded \\$1 million.Damaging floods of April 1-7 followed one of the wettest winters in California history. Swollen streams overflowed their banks throughout the central part of the State, and discharge peaks on many streams exceeded those .of the floods of December 1955. Most severely flooded was the San Francisco Bay area. Total flood damage was estimated at \\$23 million.The storms and floods of April-May in Louisiana and adjacent States outranked all other floods in the United States during 1958 with respect to intensity of rain over a large area, number of streams having maximum discharge of record, rare occurrence of peaks, and great amount (\\$21 million) of resultant damage.Heavy rains on June 8-15 caused one of the greatest summer floods of record in central Indiana. Peak discharges were high and of rare occurrences. Failure of numerous levees along the Wabash River caused great damage. Crop damage alone was estimated at \\$48 million.Intense rains of July 1-2 caused record-breaking floods in southwestern Iowa. Rapid rises and the great magnitude of the floods on small streams resulted in 18 deaths and many injuries. Six towns and cities along the East Nishnabotna River and its tributaries were particularly hard hit; rural damage was also high. Total damage was estimated at \\$15 million.Heavy rains (as much as 40 inches during the last 2 weeks in September) from the middle of September to the middle of October caused destructive floods along the Rio Grande in Texas and Mexico. Many communities were isolated by the flood waters, and damage to crops was great.In addition to the 7 floods mentioned above, 21 others of lesser magnitude are reported in this annual summary.

Hurricane Isabel, Amount of Atmospheric Water Vapor Observed By AIRS

NASA Technical Reports Server (NTRS)

2003-01-01

[figure removed for brevity, see original site] Figure 1

These false-color images show the amount of atmospheric water vapor observed by AIRS two weeks prior to the passage of Hurricane Isabel, and then when it was a Category 5 storm. The region shown includes parts of South America and the West Indies. Puerto Rico is the large island below the upper left corner.

Total water vapor represents the depth of a layer if all the water vapor in the atmosphere were to condense and fall to the surface. The color bar on the right sides of the plots give the thickness of this layer in millimeters (mm). The first image, from August 28, shows typical tropical water vapor amounts over the ocean: between roughly 25 and 50 mm, or 1 to 2 inches. The highest values of roughly 80 mm, seen as a red blob over South America, corresponds to intense thunderstorms. Thunderstorms pull in water vapor from surrounding regions and concentrate it, with much of it then falling as rain.

Figure 1 shows total water during the passage of Hurricane Isabel on September 13. The storm is apparent: the ring of moderate values surrounding a very strong maximum of 100 mm. Total water of more than 80 mm is unusual, and these values correspond to the intense thunderstorms contained within Isabel. The thunderstorms--and the large values of total water--are fed by evaporation from the ocean in the hurricane's high winds. The water vapor near the center of the storm does not remain there long, since hurricane rain rates as high 50 mm (2 inches) per hour imply rapid cycling of the water we observe. Away from the storm the amount of total water vapor is rather low, associated with fair weather where air that ascended near the storm's eye returns to earth, having dropped its moisture as rain. Also seen in the second images are two small regions of about 70 mm of total water over south America. These are yet more thunderstorms, though likely much more benign than those in Isabel.

The Atmospheric Infrared Sounder Experiment, with its visible, infrared, and microwave detectors, provides a three-dimensional look at Earth's weather. Working in tandem, the three instruments can make simultaneous observations all the way down to the Earth's surface, even in the presence of heavy clouds. With more than 2,000 channels sensing different regions of the atmosphere, the system creates a global, 3-D map of atmospheric temperature and humidity and provides information on clouds, greenhouse gases, and many other atmospheric phenomena. The AIRS Infrared Sounder Experiment flies onboard NASA's Aqua spacecraft and is managed by NASA's Jet Propulsion Laboratory, Pasadena, Calif., under contract to NASA. JPL is a division of the California Institute of Technology in Pasadena.

Super Typhoon Halong off Taiwan

NASA Technical Reports Server (NTRS)

2002-01-01

On July 14, 2002, Super Typhoon Halong was east of Taiwan (left edge) in the western Pacific Ocean. At the time this image was taken the storm was a Category 4 hurricane, with maximum sustained winds of 115 knots (132 miles per hour), but as recently as July 12, winds were at 135 knots (155 miles per hour). Halong has moved northwards and pounded Okinawa, Japan, with heavy rain and high winds, just days after tropical Storm Chataan hit the country, creating flooding and killing several people. The storm is expected to be a continuing threat on Monday and Tuesday. This image was acquired by the Moderate Resolution Imaging Spectroradiometer (MODIS) on the Terra satellite on July 14, 2002. Please note that the high-resolution scene provided here is 500 meters per pixel. For a copy of the scene at the sensor's fullest resolution, visit the MODIS Rapid Response Image Gallery. Image courtesy Jacques Descloitres, MODIS Land Rapid Response Team at NASA GSFC

An Examination of Selected Historical Rainfall-Induced Debris-Flow Events within the Central and Southern Appalachian Mountains of the Eastern United States

USGS Publications Warehouse

Wieczorek, Gerald F.; Eaton, L. Scott; Morgan, Benjamin A.; Wooten, R.M.; Morrissey, M.

2009-01-01

Generally, every several years, heavy amounts of rainfall trigger a large number of debris flows within the central and southern Appalachian Mountains of the Eastern United States. These types of landslides damage buildings, disrupt infrastructure, and occasionally injure and kill people. One of the first large debris flows was described in Pennsylvania in August 1779. The most destructive event occurred during August 19-20, 1969, in Nelson County, Va. During a period of 8 hours, 710 to 800 milimeters of rain triggered more than 3,000 landslides, killing more than 150 people. As the population increases in this region, future storms will likely increase the risks of property damage and loss of life. We provide a general overview of debris flows in the Appalachians, using a compilation of 19 storm events for which rainfall, duration of the storm, and descriptions of the resulting landslides have been substantially documented.

Deciphering the expression of climate change within the Lower Colorado River basin by stochastic simulation of convective rainfall

NASA Astrophysics Data System (ADS)

Bliss Singer, Michael; Michaelides, Katerina

2017-10-01

In drylands, convective rainstorms typically control runoff, streamflow, water supply and flood risk to human populations, and ecological water availability at multiple spatial scales. Since drainage basin water balance is sensitive to climate, it is important to improve characterization of convective rainstorms in a manner that enables statistical assessment of rainfall at high spatial and temporal resolution, and the prediction of plausible manifestations of climate change. Here we present a simple rainstorm generator, STORM, for convective storm simulation. It was created using data from a rain gauge network in one dryland drainage basin, but is applicable anywhere. We employ STORM to assess watershed rainfall under climate change simulations that reflect differences in wetness/storminess, and thus provide insight into observed or projected regional hydrologic trends. Our analysis documents historical, regional climate change manifesting as a multidecadal decline in rainfall intensity, which we suggest has negatively impacted ephemeral runoff in the Lower Colorado River basin, but has not contributed substantially to regional negative streamflow trends.

The Complex Relationship Between Heavy Storms and Floods: Implication on Stormwater Drainage design and Management

NASA Astrophysics Data System (ADS)

Demissie, Y.; Mortuza, M. R.; Moges, E.; Yan, E.; Li, H. Y.

2017-12-01

Due to the lack of historical and future streamflow data for flood frequency analysis at or near most drainage sites, it is a common practice to directly estimate the design flood (maximum discharge or volume of stream for a given return period) based on storm frequency analysis and the resulted Intensity-Duration-Frequency (IDF) curves. Such analysis assumes a direct relationship between storms and floods with, for example, the 10-year rainfall expected to produce the 10-year flood. However, in reality, a storm is just one factor among the many other hydrological and metrological factors that can affect the peak flow and hydrograph. Consequently, a heavy storm does not necessarily always lead to flooding or a flood events with the same frequency. This is evident by the observed difference in the seasonality of heavy storms and floods in most regions. In order to understand site specific causal-effect relationship between heavy storms and floods and improve the flood analysis for stormwater drainage design and management, we have examined the contributions of various factors that affect floods using statistical and information theory methods. Based on the identified dominant causal-effect relationships, hydrologic and probability analyses were conducted to develop the runoff IDF curves taking into consideration the snowmelt and rain-on-snow effect, the difference in the storm and flood seasonality, soil moisture conditions, and catchment potential for flash and riverine flooding. The approach was demonstrated using data from military installations located in different parts of the United States. The accuracy of the flood frequency analysis and the resulted runoff IDF curves were evaluated based on the runoff IDF curves developed from streamflow measurements.

September 2013 Storm and Flood Assessment Report

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

Walterscheid, J. C.

2015-12-21

Between September 10 and 17, 2013, New Mexico and Colorado received a historically large amount of precipitation (Figure 1). This report assesses the damage caused by flooding along with estimated costs to repair the damage at Los Alamos National Laboratory (the Laboratory) on the Pajarito Plateau. Los Alamos County, New Mexico, received between 200% and 600% of the normal precipitation for this time period (Figure 2), and the Laboratory received approximately 450% percent of its average precipitation for September (Figure 3). As a result, the Laboratory was inundated with rain, including the extremely large, greater-than-1000-yr return period event that occurredmore » between September 12 and 13 (Table 1). With saturated antecedent soil conditions from the September 10 storm, when the September 12 to September 13 storm hit, the flooding was disastrous to the Laboratory’s environmental infrastructure, including access roads, gage stations, watershed controls, control measures installed under the National Pollutant Discharge Elimination System Permit (hereafter, the Individual Permit), and groundwater monitoring wells (Figures 4 through 21). From September 16 to October 1, 2013, the Laboratory completed field assessments of environmental infrastructure and generated descriptions and estimates of the damage, which are presented in spreadsheets in Attachments 1 to 4 of this report. Section 2 of this report contains damage assessments by watershed, including access roads, gage stations, watershed controls, and control measures installed under the Individual Permit. Section 3 contains damage assessments of monitoring wells by the groundwater monitoring groups as established in the Interim Facility-Wide Groundwater Monitoring Plan for Monitoring Year 2014. Section 4 addresses damage and loss of automated samplers. Section 5 addresses sediment sampling needs, and Section 6 is the summary of estimated recovery costs from the significant rain and flooding during September 2013.« less

Storm-scale dynamics of bacterial community composition in throughfall and stemflow

NASA Astrophysics Data System (ADS)

Van Stan, J. T., II; Teachey, M. E.; Pound, P.; Ottesen, E. A.

2017-12-01

Transport of bacteria between ecosystem spheres can significantly affect microbially-mediated biogeochemical processes. During rainfall, there is a large, temporally-concentrated exchange of bacteria between the forest phyllosphere and the pedosphere by rain dripping from canopy surfaces, as throughfall (TF), and draining to the stem, as stemflow (SF). Many phyllosphere bacteria possibly transported by TF and SF have been linked to important litter and soil processes (like cyanobacteria and actinobacteria). Despite this, no work has applied high throughput DNA sequencing to assess the community composition of bacteria transported by TF and SF. We characterized bacterial community composition for TF and SF from an epiphyte-laden (Tillandsia usneoides L., Spanish moss) southern live oak (Quercus virginiana) forest in southeastern Georgia (USA) to address two hypotheses: that bacterial community composition will differ between (1) TF and SF, and (2) TF sampled beneath bare and epiphyte-laden canopy. Variability in family-level bacterial abundance, Bray-Curtis dissimilarity, and Shannon diversity index was greater between storms than between net rainfall fluxes. In fact, TF and SF bacterial communities were relatively similar for individual storms and may be driven by pre-storm atmospheric deposition rather than the communities affixed to leaves, bark, and epiphyte surfaces.

Tropical Storm Yagi in the North Pacific Ocean

NASA Image and Video Library

2017-12-08

In early June, Tropical storm Yagi developed from Tropical Depression 03W in the Western North Pacific Ocean. The Moderate Resolution Imaging Spectroradiometer (MODIS) aboard NASA’s Terra satellite captured this true-color image on June 10 at 1:55 UTC (9:55 P.M.) as the storm was spinning near 25.0 north and 135.2 east, or about 396 miles (637 km) west of Iwo Jima, Japan. At that time, the storm had maximum sustained winds 51.7 mph (83.3 km/h). The image shows a tightly-wrapped circulation, a clouded eye and storm bands reached furthest out in the northeast quadrant. The tropical depression first formed on June 6 east of the Philippines, and intensified on the weekend of June 8-9, when it was given the name of Yagi. Also known as Dante, the storm reached the maximum wind speeds on June 10 and 11, after which it began to weaken as it moved into cooler waters. On June 14, Yagi’s remnants passed about 200 miles south of Tokyo, and brought soaking rains to the coastline of Japan’s Honshu Island. Credit: NASA/GSFC/Jeff Schmaltz/MODIS Land Rapid Response Team NASA image use policy. NASA Goddard Space Flight Center enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission. Follow us on Twitter Like us on Facebook Find us on Instagram

Atmosphere-Wave-Ocean Coupling from Regional to Global Earth System Models for High-Impact Extreme Weather Prediction

NASA Astrophysics Data System (ADS)

Chen, S. S.; Curcic, M.

2017-12-01

The need for acurrate and integrated impact forecasts of extreme wind, rain, waves, and storm surge is growing as coastal population and built environment expand worldwide. A key limiting factor in forecasting impacts of extreme weather events associated with tropical cycle and winter storms is fully coupled atmosphere-wave-ocean model interface with explicit momentum and energy exchange. It is not only critical for accurate prediction of storm intensity, but also provides coherent wind, rian, ocean waves and currents forecasts for forcing for storm surge. The Unified Wave INterface (UWIN) has been developed for coupling of the atmosphere-wave-ocean models. UWIN couples the atmosphere, wave, and ocean models using the Earth System Modeling Framework (ESMF). It is a physically based and computationally efficient coupling sytem that is flexible to use in a multi-model system and portable for transition to the next generation global Earth system prediction mdoels. This standardized coupling framework allows researchers to develop and test air-sea coupling parameterizations and coupled data assimilation, and to better facilitate research-to-operation activities. It has been used and extensively tested and verified in regional coupled model forecasts of tropical cycles and winter storms (Chen and Curcic 2016, Curcic et al. 2016, and Judt et al. 2016). We will present 1) an overview of UWIN and its applications in fully coupled atmosphere-wave-ocean model predictions of hurricanes and coastal winter storms, and 2) implenmentation of UWIN in the NASA GMAO GEOS-5.

Climate scenarios for California

USGS Publications Warehouse

Cayan, Daniel R.; Maurer, Ed; Dettinger, Mike; Tyree, Mary; Hayhoe, Katharine; Bonfils, Celine; Duffy, Phil; Santer, Ben

2006-01-01

In all of the simulations, most precipitation continues to occur in winter, with virtually all derived from North Pacific winter storms. Relatively little change in overall precipitation is projected. Climate warming has a profound influence in diminishing snow accumulations, because there is more rain and less snow, and earlier snowmelt. These snow losses increase as the warming increases, so that they are most severe under climate changes projected by the more sensitive model with the higher GHG emissions.

KSC-08pd2552

NASA Image and Video Library

2008-09-05

CAPE CANAVERAL, Fla. – A missing part of a panel on the southeast corner of the Vehicle Assembly Building at NASA's Kennedy Space Center is minor damage caused by Tropical Storm Hanna as it passed Florida’s east coast. The panel bent a UHF antenna on the roof of the Launch Control Center. Hanna kept well offshore, bearing only bursts of rain and wind along the coastline as it moved north. Photo credit: NASA/Jack Pfaller

Rainfall and Erosion Response Following a Southern California Wildfire

NASA Astrophysics Data System (ADS)

Wohlgemuth, P. M.; Robichaud, P. R.; Brown, R. E.

2011-12-01

Wildfire renders landscapes susceptible to flooding and accelerated surface erosion. Consumption of the vegetation canopy and the litter or duff layer removes resistances to the agents of erosion. Moreover, changes in soil properties can restrict infiltration, increasing the effectiveness of the driving forces of rainsplash and surface runoff. However, it is unclear whether surface erosion varies linearly with rainfall amounts and intensities or if thresholds exist beyond which erosion increases in a different trajectory. The Santiago Fire burned over 11000 ha in northeastern Orange County, California in October 2007. The burn area consists of a deeply dissected mountain block underlain by sedimentary and metamorphic rocks that produce erosive soils. Regional erosion and sediment transport is triggered by winter cyclonic storms. Recording raingages were deployed across a vertical gradient within the burned area and silt fences were constructed to monitor hillslope erosion. During the study period initial storms were characterized by moderate rainfall (amounts less than 25 mm with peak 10-minute intensities of less than 10 mm per hr). Surface erosion was concomitantly minor, less than 0.4 Mg per ha. However, an unusual thunderstorm in late May 2008 produced spatially variable rainfall and consequent surface erosion across the study area. The raingage at a lower elevation site measured 41.4 mm of rain for this storm with a peak 10-minute intensity of 81 mm per hr. The silt fences were overtopped, yielding a minimum value of 18.5 Mg per ha. In contrast, the raingage at an upper elevation site recorded 19.6 mm of rain with a peak 10-minute intensity of 50 mm per hr. Surface erosion in the higher elevation sites was negligible (0.1 Mg per ha). Subsequently, individual storms exceeded 100 mm of rainfall but peak 10-minute intensities never approached those of the May thunderstorm. Erosion was moderate (mostly less than 5 Mg per ha), albeit influenced by the presence of regrowing vegetation. We therefore believe that surface erosion in the immediate postfire environment is more related to storm intensity than rainfall amount. Even allowing for site-to-site differences and site changes over the first postfire winter season, it is clear that some threshold in erosion response was crossed at the lower elevation sites during the May 2008 thunderstorm. We suggest that this represents a threshold of peak 10-minute intensity of between 50 and 80 mm per hr.

Pollen resistance to water in 80 angiosperm species: flower structures protect rain-susceptible pollen.

PubMed

Mao, Yun-Yun; Huang, Shuang-Quan

2009-08-01

Flowers exhibit adaptive responses to biotic and abiotic factors. It remains unclear whether pollen susceptibility to rain damage plays a role in the evolution of floral form. We investigated flower performance in rain and compared pollen longevity in dry conditions, pure water and solutions with different sucrose concentrations in 80 flowering species from 46 families with diverse floral shapes and pollination modes. A pollen viability test showed that pollen longevity in all studied species was greatly reduced by wetting. We found that pollen of species with complete protection by flower structures was susceptible to water damage and a high proportion of resistant pollen occurred in unprotected species. Flowers whose structures expose pollen to rain may also reduce rain damage through temporal patterns of pollen presentation. This prediction was supported by our direct measurement of pollen presentation duration on rainy days. Our observations showed that variation in pollen performance in water was associated with differences in floral forms. Water-resistant pollen and extended pollen presentation duration were favored by selection via rain contact in species in which pollen was not protected from rain. These findings support the functional hypothesis that flower structures protect susceptible pollen from rain, demonstrating that rain acts as a force shaping floral form.

Relationships between Hg Air-surface exchange, Soil Moisture and Precipitation at a Background Vegetated Site in South-Eastern Australia.

NASA Astrophysics Data System (ADS)

Macsween, K.; Edwards, G. C.

2017-12-01

Despite many decades of research, the controlling mechanisms of mercury (Hg) air-surface exhange are still poorly understood. Particularly in Australian ecosystems where there are few anthropogenic inputs. A clear understanding of these mechanisms is vital for accurate representation in the global Hg models, particularly regarding re-emission. Water is known to have a considerable influence on Hg exchange within a terrestrial ecosystem. Precipitation has been found to cause spikes is Hg emissions during the initial stages of rain event. While, Soil moisture content is known to enhance fluxes between 15 and 30% Volumetric soil water (VSW), above which fluxes become suppressed. Few field experiments exist to verify these dominantly laboratory or controlled experiments. Here we present work looking at Hg fluxes over an 8-month period at a vegetated background site. The aim of this study is to identify how changes to precipitation intensity and duration, coupled with variable soil moisture content may influence Hg flux across seasons. As well as the influence of other meteorological variables. Experimentation was undertaken using aerodynamic gradient micrometeorological flux method, avoiding disruption to the surface, soil moisture probes and rain gauge measurements to monitor alterations to substrate conditions. Meteorological and air chemistry variables were also measured concurrently throughout the duration of the study. During the study period, South-Eastern Australia experienced several intense east coast low storm systems during the Autumn and Spring months and an unusually dry winter. VSW rarely reached above 30% even following the intense rainfall experienced during the east coast lows. The generally dry conditions throughout winter resulted in an initial spike in Hg emissions when rainfall occurred. Fluxes decreased shortly after the rain began but remained slightly elevated. Given the reduced net radiation and cooler temperatures experienced during the winter months soils took several days to dry out, resulting in slightly enhanced fluxes for the days preceding rainfall. It is thought that seasonality of rainfall has a significant impact of Hg air-surface exchange trends, both through increased recovery times once rain has past and through the increased occurrence of major storm events.

The study of Merydunal and Zonal Index and its relationships with Cyclone Gonu

NASA Astrophysics Data System (ADS)

Ezzatian, Victoria

2010-05-01

Distinguish the integrated natural disaster management is basic, also there happens rarely during 100 years. Cyclone Gonu, an unusually strong tropical cyclone, developed in the eastern part of the Arabian Sea on June 1st. The cyclone made landfall in Oman on the 6th with maximum sustained winds near 148 km/hr. A few days prior to landfall, Gonu had intensified to a powerful super cyclonic storm with maximum sustained winds near 260 km/hr on the 5th, becoming the first documented super cyclone in the Arabian Sea and tied for the strongest cyclone in the North Indian Ocean. After making landfall in Oman, Gonu moved through the Gulf of Oman making a second landfall in Iran. Tropical Cyclone Gonu affected more than 20,000 people and was responsible for 49 fatalities and 27 missing people in Oman. Gonu brought heavy rainfall which caused floods and landslides. Meanwhile in Iran 5 fatalities were reported and 9 people remain missing. Tropical cyclones as strong as Gonu are rare in the Arabian Sea. Severe thunderstorms, associated with an outer band of the tropical cyclone Yemyin , produced heavy rains and winds during June 23-25. The storms produced heavy rains which caused floodings and destroyed thousands of homes .Tropical Cyclone Yemyin developed as a depression in the Bay of Bengal on the 21st and made landfall in India's southern state on the 22nd. Yemyin brought heavy rain in the southern parts of India, leaving over 254 mm of rain. After crossing over India, Yemyin moved into the Arabian Sea and began moving towards the northwest. On June 26, the cyclone intensified and maximum sustained winds reached 93 km/hr. The cyclone was responsible for at least 21 fatalities in the Baluchistan province. Meanwhile in Afghanistan, Yemyin produced heavy rainfall which prompted floods that were responsible for 56 deaths and left thousands of people homeless . Because of these happenings we decided surveying the synoptic patterns in this month. Key words: Tropical cyclones, Tropical Cyclone Gonu, merridional index, zonal index .

Validation of Rain Rate Retrievals for the Airborne Hurricane Imaging Radiometer (HIRAD)

NASA Technical Reports Server (NTRS)

Jacob, Maria Marta; Salemirad, Matin; Jones, W. Linwood; Biswas, Sayak; Cecil, Daniel

2015-01-01

The NASA Hurricane and Severe Storm Sentinel (HS3) mission is an aircraft field measurements program using NASA's unmanned Global Hawk aircraft system for remote sensing and in situ observations of Atlantic and Caribbean Sea hurricanes. One of the principal microwave instruments is the Hurricane Imaging Radiometer (HIRAD), which measures surface wind speeds and rain rates. For validation of the HIRAD wind speed measurement in hurricanes, there exists a comprehensive set of comparisons with the Stepped Frequency Microwave Radiometer (SFMR) with in situ GPS dropwindsondes [1]. However, for rain rate measurements, there are only indirect correlations with rain imagery from other HS3 remote sensors (e.g., the dual-frequency Ka- & Ku-band doppler radar, HIWRAP), which is only qualitative in nature. However, this paper presents results from an unplanned rain rate measurement validation opportunity that occurred in 2013, when HIRAD flew over an intense tropical squall line that was simultaneously observed by the Tampa NEXRAD meteorological radar (Fig. 1). During this experiment, Global Hawk flying at an altitude of 18 km made 3 passes over the rapidly propagating thunderstorm, while the TAMPA NEXRAD perform volume scans on a 5-minute interval. Using the well-documented NEXRAD Z-R relationship, 2D images of rain rate (mm/hr) were obtained at two altitudes (3 km & 6 km), which serve as surface truth for the HIRAD rain rate retrievals. A preliminary comparison of HIRAD rain rate retrievals (image) for the first pass and the corresponding closest NEXRAD rain image is presented in Fig. 2 & 3. This paper describes the HIRAD instrument, which 1D synthetic-aperture thinned array radiometer (STAR) developed by NASA Marshall Space Flight Center [2]. The rain rate retrieval algorithm, developed by Amarin et al. [3], is based on the maximum likelihood estimation (MLE) technique, which compares the observed Tb's at the HIRAD operating frequencies of 4, 5, 6 and 6.6 GHz with corresponding theoretical Tb values from a forward radiative transfer model (RTM). The optimum solution is the integrated rain rate that minimizes the difference between RTM and observed values. Because the excess Tb from rain comes from the direct upwelling and the indirect reflected downwelling paths through the atmosphere, there are several assumptions made for the 2D rain distribution in the antenna incident plane (crosstrack to flight direction). The opportunity to knowing 2D rain surface truth from NEXRAD at two different altitudes will enable a comprehensive evaluation to be preformed and reported in this paper.

Operation of a real-time warning system for debris flows in the San Francisco bay area, California

USGS Publications Warehouse

Wilson, Raymond C.; Mark, Robert K.; Barbato, Gary; ,

1993-01-01

The United States Geological Survey (USGS) and the National Weather Service (NWS) have developed an operational warning system for debris flows during severe rainstorms in the San Francisco Bay region. The NWS makes quantitative forecasts of precipitation from storm systems approaching the Bay area and coordinates a regional network of radio-telemetered rain gages. The USGS has formulated thresholds for the intensity and duration of rainfall required to initiate debris flows. The first successful public warnings were issued during a severe storm sequence in February 1986. Continued operation of the warning system since 1986 has provided valuable working experience in rainfall forecasting and monitoring, refined rainfall thresholds, and streamlined procedures for issuing public warnings. Advisory statements issued since 1986 are summarized.

Development and testing of highway storm-sewer flow measurement and recording system

USGS Publications Warehouse

Kilpatrick, F.A.; Kaehrle, W.R.; Hardee, Jack; Cordes, E.H.; Landers, M.N.

1985-01-01

A comprehensive study and development of measuring instruments and techniques for measuring all components of flow in a storm-sewer drainage system was undertaken by the U.S. Geological Survey under the sponsorship of the Federal Highway Administration. The study involved laboratory and field calibration and testing of measuring flumes, pipe insert meters, weirs, electromagnetic velocity meters as well as the development and calibration of pneumatic-bubbler pressure transducer head measuring systems. Tracer-dilution and acoustic flow meter measurements were used in field verification tests. A single micrologger was used to record data from all the above instruments as well as from a tipping-bucket rain gage and also to activate on command the electromagnetic velocity meter and tracer-dilution systems. (Author 's abstract)

Supertyphoon Nepartak Barreling Toward Taiwan Viewed by NASA MISR

NASA Image and Video Library

2016-07-08

Typhoon Nepartak, the first large typhoon in the northwest Pacific this season, is currently taking aim at the east coast of Taiwan. Over the past few days, Nepartak has rapidly gained strength, growing from a tropical storm to the equivalent of a Category 5 hurricane with sustained wind speeds of more than 160 miles (258 kilometers) per hour. Taiwan's Central Weather Bureau has issued a torrential rain warning, bracing for likely flooding as 5 to 15 inches (13 to 38 centimeters) of rain are expected to fall over Taiwan during the storm's passage. Waves of up to 40 feet (12 meters) are predicted on the coast as the typhoon approaches, and air and train travel have been severely impacted. The typhoon is currently moving at about 10 miles per hour (16 kilometers) to the west-northwest, and is predicted to pass over Taiwan within the next day and then hit the coast of mainland China. Central and eastern China are poorly situated to absorb the rainfall from Nepartak after suffering the effects of severe monsoon flooding, which has killed at least 140 people in the past week. The Multi-angle Imaging SpectroRadiometer (MISR) instrument aboard NASA's Terra satellite captured this view of Typhoon Nepartak on July 7, 2016, at 10:30 a.m. local time (2:30 a.m. UTC). On the left is an image from the nadir (vertical pointing) camera, which shows the central portion of Nepartak and the storm's eye. The image is about 235 miles (378 kilometers) across. The island of Manila in the Philippines, about 250 miles (400 kilometers) south of Taiwan, is visible to the southwest of the eye. The image shows that Nepartak's center is extremely compact, rather than broken up into spiral bands as is more typical of typhoons. This means that the storm may retain more of its strength as it passes over land. MISR uses nine cameras to capture images of the typhoon from different angles. This provides a stereographic view, which can be used to determine the height of the storm's cloud tops. These heights are plotted in the middle panel, superimposed on the image. This shows that the cloud tops are relatively low, about 2.5 miles (4 kilometers), in the eye, but much higher, up to 12.5 miles (20 kilometers), just outside it. By tracking the motion of clouds as they are viewed by each of the nine cameras over about seven minutes, it is possible to also derive how fast the clouds are moving due to wind. These wind vectors are superimposed on the image in the right panel. The length of each arrow shows the wind speed at that location (compare to the 45 miles per hour or 20 meters per second arrow in the legend), and the color shows the height at which the wind is being computed. The motion of the low-level winds (red and yellow arrows) is counterclockwise, while the motion of the high winds (blue and purple arrows) is mostly clockwise. This is because hurricanes draw in warm, moist air at low altitudes, which then flows upward around the eye, releases its moisture as rain, and moves outward at high altitudes. As is typical of these types of storm systems, the inflowing low winds and the outflowing high winds spin in different directions. http://photojournal.jpl.nasa.gov/catalog/PIA20719

A field study to evaluate runoff quality from green roofs.

PubMed

Vijayaraghavan, K; Joshi, U M; Balasubramanian, R

2012-03-15

Green (vegetated) roofs are emerging as practical strategies to improve the environmental quality of cities. However, the impact of green roofs on the storm water quality remains a topic of concern to city planners and environmental policy makers. This study investigated whether green roofs act as a source or a sink of various metals (Na, K, Ca, Mg, Al, Fe, Cu, Cd, Pb, Zn, Mn, Cr, Ni, Li and Co), inorganic anions (NO3-, NO2-, PO4(3-), SO4(2-), Cl-, F- and Br-) and cation (NH4+). A series of green roof assemblies were constructed. Four different real rain events and several artificial rain events were considered for the study. Results showed that concentrations of most of the chemical components in runoff were highest during the beginning of rain events and subsided in the subsequent rain events. Some of the important components present in the runoff include Na, K, Ca, Mg, Li, Fe, Al, Cu, NO3-, PO4(3-) and SO4(2-). However, the concentration of these chemical components in the roof runoff strongly depends on the nature of substrates used in the green roof and the volume of rain. Based on the USEPA standards for freshwater quality, we conclude that the green roof used in this study is reasonably effective except that the runoff contains significant amounts of NO3- and PO4(3-). Copyright © 2011 Elsevier Ltd. All rights reserved.

Changing character of rainfall in eastern China, 1951–2007

NASA Astrophysics Data System (ADS)

Day, Jesse A.; Fung, Inez; Liu, Weihan

2018-03-01

The topography and continental configuration of East Asia favor the year-round existence of storm tracks that extend thousands of kilometers from China into the northwestern Pacific Ocean, producing zonally elongated patterns of rainfall that we call “frontal rain events.” In spring and early summer (known as “Meiyu Season”), frontal rainfall intensifies and shifts northward during a series of stages collectively known as the East Asian summer monsoon. Using a technique called the Frontal Rain Event Detection Algorithm, we create a daily catalog of all frontal rain events in east China during 1951–2007, quantify their attributes, and classify all rainfall on each day as either frontal, resulting from large-scale convergence, or nonfrontal, produced by local buoyancy, topography, or typhoons. Our climatology shows that the East Asian summer monsoon consists of a series of coupled changes in frontal rain event frequency, latitude, and daily accumulation. Furthermore, decadal changes in the amount and distribution of rainfall in east China are overwhelmingly due to changes in frontal rainfall. We attribute the “South Flood–North Drought” pattern observed beginning in the 1980s to changes in the frequency of frontal rain events, while the years 1994–2007 witnessed an uptick in event daily accumulation relative to the rest of the study years. This particular signature may reflect the relative impacts of global warming, aerosol loading, and natural variability on regional rainfall, potentially via shifting the East Asian jet stream.

Protective broadband window coatings

NASA Astrophysics Data System (ADS)

Askinazi, Joel; Narayanan, Authi A.

1997-06-01

Optical windows employed in current and future airborne and ground based optical sensor systems are required to provide long service life under extreme environmental conditions including blowing sand and high speed rain. State of the art sensor systems are employing common aperture windows which must provide optical bandpasses from the TV to the LWIR. Operation Desert Storm experience indicates that current optical coatings provide limited environmental protection which adversely affects window life cycle cost. Most of these production coatings also have limited optical bandpasses (LWIR, MWIR, or TV-NIR). A family of optical coatings has been developed which provide a significant increase in rain and sand impact protection to current optical window materials. These coatings can also be tailored to provide either narrow optical bandwidth (e.g., LWIR) or broadband transmittance (TV- LWIR). They have been applied to a number of standard optical window materials. These coating have successfully completed airborne rain and sand abrasion test with minimal impact on optical window performance. Test results are presented. Low cost service life is anticipated as well as the ability to operate windows in even more taxing environments than currently feasible.

Using NDVI to measure precipitation in semi-arid landscapes

USGS Publications Warehouse

Birtwhistle, Amy N.; Laituri, Melinda; Bledsoe, Brian; Friedman, Jonathan M.

2016-01-01

Measuring precipitation in semi-arid landscapes is important for understanding the processes related to rainfall and run-off; however, measuring precipitation accurately can often be challenging especially within remote regions where precipitation instruments are scarce. Typically, rain-gauges are sparsely distributed and research comparing rain-gauge and RADAR precipitation estimates reveal that RADAR data are often misleading, especially for monsoon season convective storms. This study investigates an alternative way to map the spatial and temporal variation of precipitation inputs along ephemeral stream channels using Normalized Difference Vegetation Index (NDVI) derived from Landsat Thematic Mapper imagery. NDVI values from 26 years of pre- and post-monsoon season Landsat imagery were derived across Yuma Proving Ground (YPG), a region covering 3,367 km2 of semiarid landscapes in southwestern Arizona, USA. The change in NDVI from a pre-to post-monsoon season image along ephemeral stream channels explained 73% of the variance in annual monsoonal precipitation totals from a nearby rain-gauge. In addition, large seasonal changes in NDVI along channels were useful in determining when and where flow events have occurred.

Preliminary results from multiparameter airborne rain radar measurement in the western Pacific

NASA Technical Reports Server (NTRS)

Kumagai, Hiroshi; Meneghini, Robert; Kozu, Toshiaki

1993-01-01

Preliminary results are presented from multiparameter airborne radar measurements of tropical storms. The experiment was conducted in the western Pacific in September 1990 with the NASA DC-8 aircraft that was equipped with a dual-wavelength radar at X and Ka bands and several microwave radiometers. The modification to dual-polarization at X-band radar enabled measurements of the linear depolarization ratio (LDR). Vertical profiles of dual-polarization and dual-frequency observables for an example of stratiform rain and three examples of convective rain cells are examined. It is shown that at nadir incidence the LDR measurement often can be used to distinguish the phase states of the hydrometeors and to identify the melting layer. In addition to the information concerning particle shape and orientation from LDR, the ratio of the radar reflectivity factors in two frequency bands (X and Ka bands) provides insight into particle size. The capabilities of dual-wavelength and dual-polarization radar in the identification of particle size and phase will be important considerations in the design of future spaceborne weather radars.

Changes in the TRMM Version-5 and Version-6 Precipitation Radar Products Due to Orbit Boost

NASA Technical Reports Server (NTRS)

Liao, Liang; Meneghini, Robert

2010-01-01

The performance of the version-5 and version-6 Tropical Rainfall Measuring Mission (TRMM) Precipitation Radar (PR) products before and after the satellite orbit boost is assessed through a series of comparisons with Weather Surveillance Radar (WSR)-88D ground-based radar in Melbourne, Florida. Analysis of the comparisons of radar reflectivity near the storm top from the ground radar and both versions of the PR indicates that the PR bias relative to the WSR radar at Melbourne is on the order of 1dB for both pre- and post-boost periods, indicating that the PR products maintain accurate calibration after the orbit boost. Comparisons with the WSR-88D near-surface reflectivity factors indicate that both versions of the PR products accurately correct for attenuation in stratiform rain. However, in convective rain, both versions exhibit negative biases in the near-surface radar reflectivity with version-6 products having larger negative biases than version-5. Rain rate comparisons between the ground and space radars show similar characteristics

Storm water contamination and its effect on the quality of urban surface waters.

PubMed

Barałkiewicz, Danuta; Chudzińska, Maria; Szpakowska, Barbara; Świerk, Dariusz; Gołdyn, Ryszard; Dondajewska, Renata

2014-10-01

We studied the effect of storm water drained by the sewerage system and discharged into a river and a small reservoir, on the example of five catchments located within the boundaries of the city of Poznań (Poland). These catchments differed both in terms of their surface area and land use (single- and multi-family housing, industrial areas). The aim of the analyses was to explain to what extent pollutants found in storm water runoff from the studied catchments affected the quality of surface waters and whether it threatened the aquatic organisms. Only some of the 14 studied variables and 22 chemical elements were important for the water quality of the river, i.e., pH, TSS, rain intensity, temperature, conductivity, dissolved oxygen, organic matter content, Al, Cu, Pb, Zn, Fe, Cd, Ni, Se, and Tl. The most serious threat to biota in the receiver came from the copper contamination of storm water runoff. Of all samples below the sewerage outflow, 74% exceeded the mean acute value for Daphnia species. Some of them exceeded safe concentrations for other aquatic organisms. Only the outlet from the industrial area with the highest impervious surface had a substantial influence on the water quality of the river. A reservoir situated in the river course had an important influence on the elimination of storm water pollution, despite the very short residence time of its water.

Investigating NWP initialization sensitivities in heavy precipitation events

NASA Astrophysics Data System (ADS)

Frediani, M. E. B.; Anagnostou, E. N.; Papadopoulos, A.

2010-09-01

This study aims to investigate the effect of different types of model initialization applied to extreme storms simulations. Storms with extreme precipitation can usually produce flash floods that cause several damages to the society. Lives and property are destroyed from the landslides when they could be speared if forecasted a few hours in advance. The forecasts depend on several factors; among them the initialization fields play an important role. These fields are the starting point for the simulation and therefore it controls the quality of the forecast. This study evaluates the sensitivities of WRF to the initialization from two perspectives, (1) resolution and (2) initial atmospheric fields. Two storms that lead to flash flood are simulated. The first one happened in Northeast Italy in 04/09/2009 (NI), and the second in Germany, in 02/06/2008 (GE). These storms present contrasting characteristics, NI was a maritime originated storm enhanced by local orography while GE was a typical summer convection. Three different sources of atmospheric fields defining the initial conditions are applied: (a) ECMWF operational analysis at resolution of 0.25 deg, (b) GFS operational analysis at 0.5deg and (c) LAPS analysis at ~15km, produced operationally at HCMR. The rainfall forecasted is compared against in situ ground radar and surface rain gauges observations through a set of quantitative precipitation forecast scores.

Quantitative estimation of Tropical Rainfall Mapping Mission precipitation radar signals from ground-based polarimetric radar observations

NASA Astrophysics Data System (ADS)

Bolen, Steven M.; Chandrasekar, V.

2003-06-01

The Tropical Rainfall Mapping Mission (TRMM) is the first mission dedicated to measuring rainfall from space using radar. The precipitation radar (PR) is one of several instruments aboard the TRMM satellite that is operating in a nearly circular orbit with nominal altitude of 350 km, inclination of 35°, and period of 91.5 min. The PR is a single-frequency Ku-band instrument that is designed to yield information about the vertical storm structure so as to gain insight into the intensity and distribution of rainfall. Attenuation effects on PR measurements, however, can be significant and as high as 10-15 dB. This can seriously impair the accuracy of rain rate retrieval algorithms derived from PR signal returns. Quantitative estimation of PR attenuation is made along the PR beam via ground-based polarimetric observations to validate attenuation correction procedures used by the PR. The reflectivity (Zh) at horizontal polarization and specific differential phase (Kdp) are found along the beam from S-band ground radar measurements, and theoretical modeling is used to determine the expected specific attenuation (k) along the space-Earth path at Ku-band frequency from these measurements. A theoretical k-Kdp relationship is determined for rain when Kdp ≥ 0.5°/km, and a power law relationship, k = a Zhb, is determined for light rain and other types of hydrometers encountered along the path. After alignment and resolution volume matching is made between ground and PR measurements, the two-way path-integrated attenuation (PIA) is calculated along the PR propagation path by integrating the specific attenuation along the path. The PR reflectivity derived after removing the PIA is also compared against ground radar observations.

Satellite Video Shows Movement of Major U.S. Winter Storm

NASA Image and Video Library

2014-02-12

A new NASA video of NOAA's GOES satellite imagery shows three days of movement of the massive winter storm that stretches from the southern U.S. to the northeast. Visible and infrared imagery from NOAA's GOES-East or GOES-13 satellite from Feb. 10 at 1815 UTC/1:15 p.m. EST to Feb. 12 to 1845 UTC/1:45 p.m. EST were compiled into a video made by NASA/NOAA's GOES Project at NASA's Goddard Space Flight Center in Greenbelt, Md. In the video, viewers can see the development and movement of the clouds associated with the progression of the frontal system and related low pressure areas that make up the massive storm. The video also shows the snow covered ground over the Great Lakes region and Ohio Valley that stretches to northern New England. The clouds and fallen snow data from NOAA's GOES-East satellite were overlaid on a true-color image of land and ocean created by data from the Moderate Resolution Imaging Spectroradiometer or MODIS instrument that flies aboard NASA's Aqua and Terra satellites. On February 12 at 10 a.m. EST, NOAA's National Weather Service or NWS continued to issue watches and warnings from Texas to New England. Specifically, NWS cited Winter Storm Warnings and Winter Weather Advisories were in effect from eastern Texas eastward across the interior section of southeastern U.S. states and across much of the eastern seaboard including the Appalachians. Winter storm watches are in effect for portions of northern New England as well as along the western slopes of northern and central Appalachians. For updates on local forecasts, watches and warnings, visit NOAA's www.weather.gov webpage. NOAA's Weather Prediction Center or WPC noted the storm is expected to bring "freezing rain spreading into the Carolinas, significant snow accumulations are expected in the interior Mid-Atlantic states tonight into Thursday and ice storm warnings and freezing rain advisories are in effect across much of central Georgia. GOES satellites provide the kind of continuous monitoring necessary for intensive data analysis. Geostationary describes an orbit in which a satellite is always in the same position with respect to the rotating Earth. This allows GOES to hover continuously over one position on Earth's surface, appearing stationary. As a result, GOES provide a constant vigil for the atmospheric "triggers" for severe weather conditions such as tornadoes, flash floods, hail storms and hurricanes. For updated information about the storm system, visit NOAA's WPC website; www.hpc.ncep.noaa.gov/ For more information about GOES satellites, visit: www.goes.noaa.gov/ or goes.gsfc.nasa.gov/ Rob Gutro NASA's Goddard Space Flight Center Credit: NOAA/NASA GOES Project NASA image use policy. NASA Goddard Space Flight Center enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission. Follow us on Twitter Like us on Facebook Find us on Instagram

Statistical Analysis of the Polarimetric Cloud Analysis and Seeding Test (POLCAST) Field Projects

NASA Astrophysics Data System (ADS)

Ekness, Jamie Lynn

The North Dakota farming industry brings in more than $4.1 billion annually in cash receipts. Unfortunately, agriculture sales vary significantly from year to year, which is due in large part to weather events such as hail storms and droughts. One method to mitigate drought is to use hygroscopic seeding to increase the precipitation efficiency of clouds. The North Dakota Atmospheric Research Board (NDARB) sponsored the Polarimetric Cloud Analysis and Seeding Test (POLCAST) research project to determine the effectiveness of hygroscopic seeding in North Dakota. The POLCAST field projects obtained airborne and radar observations, while conducting randomized cloud seeding. The Thunderstorm Identification Tracking and Nowcasting (TITAN) program is used to analyze radar data (33 usable cases) in determining differences in the duration of the storm, rain rate and total rain amount between seeded and non-seeded clouds. The single ratio of seeded to non-seeded cases is 1.56 (0.28 mm/0.18 mm) or 56% increase for the average hourly rainfall during the first 60 minutes after target selection. A seeding effect is indicated with the lifetime of the storms increasing by 41 % between seeded and non-seeded clouds for the first 60 minutes past seeding decision. A double ratio statistic, a comparison of radar derived rain amount of the last 40 minutes of a case (seed/non-seed), compared to the first 20 minutes (seed/non-seed), is used to account for the natural variability of the cloud system and gives a double ratio of 1.85. The Mann-Whitney test on the double ratio of seeded to non-seeded cases (33 cases) gives a significance (p-value) of 0.063. Bootstrapping analysis of the POLCAST set indicates that 50 cases would provide statistically significant results based on the Mann-Whitney test of the double ratio. All the statistical analysis conducted on the POLCAST data set show that hygroscopic seeding in North Dakota does increase precipitation. While an additional POLCAST field project would be necessary to obtain standardly accepted statistically significant results (p < 0.5) for the double ratio of precipitation amount, the obtained p-value of 0.063 is close and considering the positive result from other hygroscopic seeding experiments, the North Dakota Cloud Modification Project should consider implementation of hygroscopic seeding.

Quantifying Precipitation Undercatch in a Semi-arid Watershed in Southeastern Arizona

NASA Astrophysics Data System (ADS)

Demaria, E. M.; Keefer, T.; Goodrich, D. C.; Heilman, P.; Smith, J. R.; Radford, C. D.; Kautz, M. A.

2017-12-01

The observed difference in precipitation measured at above ground level (AGL) and ground-surface (PIT) rain gauges is referred to as wind-induced undercatch (U). Quantification of U is important to accurately assess the water balance and eco-hydrologic response of watersheds and for the modeling of precipitation driven processes. U is a well-known phenomenon having been documented for over one hundred years. Neff (1977), among many others, provides historical perspective on the "Jevons" effect, the increase in U with increasing height of the rain gauge above the earth's surface. U is primarily an effect of wind on precipitation whereby wind and precipitation particles interact such that U increases with increasing wind velocity and increases with smaller and lighter particles, liquid and solid. In recent decades much research on U has been undertaken in field, laboratory, and numeric modeling studies in the U.S. and Europe (e.g. Sieck et al. 2007). Much variability of U is exhibited by years, seasons and storm events. The Walnut Gulch Experimental Watershed and Long Term Agro-ecosystem Research (LTAR) site located in southeastern Arizona has been measuring precipitation at a AGL and PIT rain gauge, wind profiles, and drop size distribution for the period 2010-2015. Our results show that the cumulative precipitation difference between AGL and PIT average 6% for the six year period, but vary from 1% to 12% annually and more so seasonally. Although winter (Nov 1 - Mar 31) has greater U expressed as percentage, more than 2/3 of the total U amount occurs in summer (Jun 15-Oct 15), in the same proportion as seasonal precipitation. Regression estimated event U is greater than daily and cumulative, but may be much greater for individual storm events. The undercatch amount is linearly related to storm event intensity, increasing with increasing intensity, but the U percentage is non-linearly related and increases with decreasing intensity. In agreement with previous studies, U percentage is greater for shorter intervals, greater in winter during non-convective events than summer convective events at low intensities, and greater for faster wind speeds. Similar results are found for U amount for winter events and for wind speeds, but U amount is greater for longer intervals.

Identification of atmospheric fronts over the ocean with microwave measurements of water vapor and rain

NASA Technical Reports Server (NTRS)

Katsaros, Kristina B.; Bhatti, Iftekhar; Mcmurdie, Lynn A.; Patty, Grant W.

1989-01-01

This paper describes some basic research techniques and algorithms developed to diagnose fronts in cyclonic storms over the ocean with data from satellite-borne microwave radiometers. Methods are developed for flagging strong gradients in integrated atmospheric water vapor and the presence of rain by using data from the SSMR on board the polar orbiting Seasat and Nimbus-7 satellites. Examination of 65 frontal systems showed that the water vapor gradient flag correctly identified 86 percent of the fronts, while the precipitation flagged 91 percent. The two types of flags emphasize different portions of the cyclone and are therefore complementary. Ultimately, these techniques are intended for operational use with data from the Special Sensor Microwave Imager which was launched in June 1987 on a satellite in the Defense Meteorological Satellite Program (DMSP).

Observations of C-band Brightness Temperature from the Hurricane Imaging Radiometer (HIRAD) During GRIP

NASA Technical Reports Server (NTRS)

Miller, Timothy L.; James, M. W.; Roberts, J. B.; Buckley, C. D.; Jones, W. L.; Biswas, S.; May, C.; Ruf, C. S.; Uhlhorn, E. W.; Atlas, R.;

Tropical Storm Gaemi approaching Vietnam

NASA Image and Video Library

2017-12-08

It is easy to see the effect of the strong northeasterly wind shear battering Tropical Storm Gaemi in satellite imagery from NASA. This true-color image acquired on Oct. 5 shows a large oval-shaped area of showers and thunderstorms associated with the storm, southwest of the exposed center of circulation. NASA's Aqua satellite passed over Tropical Storm Gaemi as it was approaching Vietnam on Oct. 5, 2012 at 0550 UTC (1:50 a.m. EDT). A true-color image of the storm was captured by the Moderate Resolution Imaging Spectroradiometer (MODIS) instrument and shows bulk of showers and thunderstorms were clearly to the southwest of the center. The circulation center appears as a ring of concentric bands of clouds northeast of the large rounded area of clouds and showers associated with the storm. On Tuesday, October 5, 2012 at 1500 UTC (11 a.m. EDT), Tropical Storm Gaemi still had maximum sustained winds near 35 knots (40 mph/65 km/h) as it did 24 hours before. It was located 425 nautical miles (489 miles/787 km) east of Hue, Vietnam near 14.7 North latitude and 117.7 East longitude. Early on October 7, Tropical Storm Gaemi made landfall over Vietnam with wind speeds reported at 34 mph (55 mph), and bringing rainfall of more than 4 inches in some areas of Vietnam. Once ashore, the storm quickly moved inland and rapidly weakened as it headed towards Cambodia. With winds reduced, Gaemi served primarily as a rainmaker, but the rain may bring flooding and landslides to the region. Credit: NASA/GSFC/Jeff Schmaltz/MODIS Land Rapid Response Team NASA image use policy. NASA Goddard Space Flight Center enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission. Follow us on Twitter Like us on Facebook Find us on Instagram

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

A. M. Sexton,; A. M. Sadeghi,; X. Zhang,

The value of watershed-scale, hydrologic and water quality models to ecosystem management is increasingly evident as more programs adopt these tools to evaluate the effectiveness of different management scenarios and their impact on the environment. Quality of precipitation data is critical for appropriate application of watershed models. In small watersheds, where no dense rain gauge network is available, modelers are faced with a dilemma to choose between different data sets. In this study, we used the German Branch (GB) watershed (~50 km 2), which is included in the USDA Conservation Effects Assessment Project (CEAP), to examine the implications of usingmore » surface rain gauge and next-generation radar (NEXRAD) precipitation data sets on the performance of the Soil and Water Assessment Tool (SWAT). The GB watershed is located in the Coastal Plain of Maryland on the eastern shore of Chesapeake Bay. Stream flow estimation results using surface rain gauge data seem to indicate the importance of using rain gauges within the same direction as the storm pattern with respect to the watershed. In the absence of a spatially representative network of rain gauges within the watershed, NEXRAD data produced good estimates of stream flow at the outlet of the watershed. Three NEXRAD datasets, including (1)*non-corrected (NC), (2) bias-corrected (BC), and (3) inverse distance weighted (IDW) corrected NEXRAD data, were produced. Nash-Sutcliffe efficiency coefficients for daily stream flow simulation using these three NEXRAD data ranged from 0.46 to 0.58 during calibration and from 0.68 to 0.76 during validation. Overall, correcting NEXRAD with rain gauge data is promising to produce better hydrologic modeling results. Given the multiple precipitation datasets and corresponding simulations, we explored the combination of the multiple simulations using Bayesian model averaging.« less

Understanding the role of fog in forest hydrology: Stable isotopes as tools for determining input and partitioning of cloud water in montane forests

USGS Publications Warehouse

Scholl, M.; Eugster, W.; Burkard, R.

2011-01-01

Understanding the hydrology of tropical montane cloud forests (TMCF) has become essential as deforestation of mountain areas proceeds at an increased rate worldwide. Passive and active cloud-water collectors, throughfall and stemflow collectors, visibility or droplet size measurements, and micrometeorological sensors are typically used to measure the fog water inputs to ecosystems. In addition, stable isotopes may be used as a natural tracer for fog and rain. Previous studies have shown that the isotopic signature of fog tends to be more enriched in the heavier isotopes 2H and 18O than that of rain, due to differences in condensation temperature and history. Differences between fog and rain isotopes are largest when rain is from synoptic-scale storms, and fog or orographic cloud water is generated locally. Smaller isotopic differences have been observed between rain and fog on mountains with orographic clouds, but only a few studies have been conducted. Quantifying fog deposition using isotope methods is more difficult in forests receiving mixed precipitation, because of limitations in the ability of sampling equipment to separate fog from rain, and because fog and rain may, under some conditions, have similar isotopic composition. This article describes the various types of fog most relevant to montane cloud forests and the importance of fog water deposition in the hydrologic budget. A brief overview of isotope hydrology provides the background needed to understand isotope applications in cloud forests. A summary of previous work explains isotopic differences between rain and fog in different environments, and how monitoring the isotopic signature of surface water, soil water and tree xylem water can yield estimates of the contribution of fog water to streamflow, groundwater recharge and transpiration. Next, instrumentation to measure fog and rain, and methods to determine isotopic concentrations in plant and soil water are discussed. The article concludes with the identification of some of the more pressing research questions in this field and offers various suggestions for future research. ?? 2010 This article is a US Government work and is in the public domain in the USA.

Freeze-thaw processes and intense winter rainfall: The one-two punch for high streambank legacy sediment and nutrient loads from Mid-Atlantic watersheds

NASA Astrophysics Data System (ADS)

Inamdar, S. P.; Johnson, E. R.; Rowland, R. D.; Walter, R. C.; Merritts, D.

2017-12-01

Historic and contemporary anthropogenic soil erosion combined with early-American milldams resulted in large deposits of legacy sediments in the valley bottoms of Piedmont watersheds of the eastern US. Breaching of milldams subsequently yielded highly incised streams with exposed vertical streambanks that are vulnerable to erosion. Streambank erosion is attributed to fluvial scouring, freeze-thaw processes and mass wasting. While streambanks represent a large reservoir of fine sediments and nutrients, there is considerable uncertainty about the contribution of these sources to watershed nonpoint source pollution. Using high-frequency hydrologic, sediment, and turbidity data we show that freeze-thaw events followed by intense winter rainstorms can export unusually high concentrations of suspended sediment and particulate nutrients from watersheds. Data from a 12 ha forested, Piedmont, stream following an intense rain event (54 mm) on February 2016 yielded suspended sediment and particulate nutrient (organic carbon and nitrogen) concentrations and exports that exceeded those from tropical storms Irene, Lee, and Sandy that had much greater rainfall and discharge amounts, but which occurred later in the year. A similar response was also observed with regards to turbidity data for USGS stream monitoring locations at Brandywine Creek (813 km2) and White Clay Creek (153 km2). We hypothesize that much of the sediment export associated with winter storms is likely due to erosion of streambank sediments and was driven by the coupled occurrence of freeze-thaw conditions and intense rainfall events. We propose that freeze-thaw erosion represents an important and underappreciated mechanism in streams that "recharges" the sediment supply, which then is available for flushing by moderate to large storms. Future climate projections indicate increased intensification of storm events and increased variability of winter temperatures. Freeze-thaw cycles coupled with winter rain events could increase erosion and transport of streambank sediments with detrimental consequences for water quality and health of downstream aquatic ecosystems. This study underscores the need to better understand the mechanisms of legacy sediment erosion and transport along with appropriate restoration strategies.

CoCoRaHS: A Community Science Program Providing Valuable Precipitation Data to Guide Decision Making

NASA Astrophysics Data System (ADS)

Robinson, D. A.; Doesken, N.

2017-12-01

CoCoRaHS is an acronym for the Community Collaborative Rain, Hail and Snow Network. It is long-running, community-based network of volunteers working together to measure and map precipitation (rain, hail and snow). Precipitation is an ideal element for public engagement because it affects everyone, it is so variable in time and space and it impacts so many things. By using a standard precipitation gauge, stressing training and education, utilizing an interactive website, and having observations undergo quality assurance, the CoCoRaHS program provides high-quality data for natural resource, education and research applications. The program currently operates in all states, Canada and the Bahamas. It originated with the Colorado Climate Center at Colorado State University in 1998 due in part to the Fort Collins flood a year prior. Upwards of 12,000 observers submit observations each day. Observations meet federal guidelines and are archived at the U.S. National Centers for Environmental Information. Because of excellent spatial coverage, data quality, practical relevance, and accessibility, CoCoRaHS observations are used by a wide variety of organizations and individuals. The U.S. National Weather Service, hydrologists, emergency managers, city utilities (water supply, storm water), insurance adjusters, the U.S. Department of Agriculture, engineers, mosquito control commissions, ranchers and farmers, outdoor and recreation interests, teachers and students are just some examples of those who use CoCoRaHS data in making well-informed, meaningful decisions. Some examples of community applications and the science utility of CoCoRaHS observations include storm warnings, water supply and demand forecasts, disaster declarations (drought, winter storm, etc.), drought and food production assessments, calibration/validation of remote sensing, infrastructure evaluation and potential redesign (ice and snow loading, bridge, storm and sewer design), recreation planning, and environmental education. This presentation will demonstrate a growing trust in volunteered data and that the CoCoRaHS program succeeds in striking a balance between education, local interest, community service and service to science.

Francis E. Walter Dam and Reservoir Project, Water Quality Data Report (RCS-DAEN-CWE-15).

DTIC Science & Technology

1980-12-01

downstream, as well as within, the lake. Analysis of these samples rives an understanding of the effect of the lake on water quality: • . The...regulation, are available for analysis . Water quality data;I (temperature, dissolved oxygen, conductivity, pH, phosphorous, total dissolved solids...depresses the pH following a rain storm. If the source of tre acid water is Fhallow lakes and swamps~lignin and tannin concentrations would be high

Evaluation of SEASAT-A SMMR derived wind speed measurements

NASA Technical Reports Server (NTRS)

1982-01-01

Wind speeds derived from versions of the least-squares and regression algorithms developed after the JASIN Workshop were evaluated. The accuracy of scanning multichannel microwave radiometer (SMMR) wind retrievals was determined in terms of the intrinsic accuracy of a baseline surface truth data set in favorable conditions. Effects which degrade the wind retrievals or introduce biases were identified and assessed. The performance of the SMMR in storms was ascertained with particular emphasis on the effects of rain.

TEMPEST-D Spacecraft

NASA Image and Video Library

2018-05-17

The complete TEMPEST-D spacecraft shown with the solar panels deployed. RainCube, CubeRRT and TEMPEST-D are currently integrated aboard Orbital ATKs Cygnus spacecraft and are awaiting launch on an Antares rocket. After the CubeSats have arrived at the station, they will be deployed into low-Earth orbit and will begin their missions to test these new technologies useful for predicting weather, ensuring data quality, and helping researchers better understand storms. https://photojournal.jpl.nasa.gov/catalog/PIA22458

ISS Passes Over Hurricane Irma 9/6/2017

NASA Image and Video Library

2017-09-06

The International Space Station’s external cameras captured another dramatic view of Hurricane Irma as it made landfall in the Caribbean Sept. 6. The powerful Category 5 storm with sustained winds of 185 mph made landfall on several islands while continuing on a westward track. Irma is expected to bring severe wind and rain to several islands in the Caribbean over the next several days with the potential to impact the Florida peninsula by week’s end.

Design and hydraulic characteristics of a field-scale bi-phasic bioretention rain garden system for storm water management.

PubMed

Yang, H; Florence, D C; McCoy, E L; Dick, W A; Grewal, P S

2009-01-01

A field-scale bioretention rain garden system was constructed using a novel bi-phasic (i.e. sequence of anaerobic to aerobic) concept for improving retention and removal of storm water runoff pollutants. Hydraulic tests with bromide tracer and simulated runoff pollutants (nitrate-N, phosphate-P, Cu, Pb, and Zn) were performed in the system under a simulated continuous rainfall. The objectives of the tests were (1) to determine hydraulic characteristics of the system, and (2) to evaluate the movement of runoff pollutants through the system. For the 180 mm/24 h rainfall, the bi-phasic bioretention system effectively reduced both peak flow (approximately 70%) and runoff volume (approximately 42%). The breakthrough curves (BTCs) of bromide tracer suggest that the transport pattern of the system is similar to dispersed plug flow under this large runoff event. The BTCs of bromide showed mean 10% and 90% breakthrough times of 5.7 h and 12.5 h, respectively. Under the continuous rainfall, a significantly different transport pattern was found between each runoff pollutant. Nitrate-N was easily transported through the system with potential leaching risk from the initial soil medium, whereas phosphate-P and metals were significantly retained indicating sorption-mediated transport. These findings support the importance of hydraulics, in combination with the soil medium, when creating bioretention systems for bioremediation that are effective for various rainfall sizes and intervals.

Evaluating the Capability of Grass Swale for the Rainfall Runoff Reduction from an Urban Parking Lot, Seoul, Korea

PubMed Central

Shafique, Muhammad; Kim, Reeho; Kyung-Ho, Kwon

2018-01-01

This field study elaborates the role of grass swale in the management of stormwater in an urban parking lot. Grass swale was constructed by using different vegetations and local soil media in the parking lot of Mapu-gu Seoul, Korea. In this study, rainfall runoff was first retained in soil and the vegetation layers of the grass swale, and then infiltrated rainwater was collected with the help of underground perforated pipe, and passed to an underground storage trench. In this way, grass swale detained a large amount of rainwater for a longer period of time and delayed peak discharge. In this field study, various real storm events were monitored and the research results were analyzed to evaluate the performance of grass swale for managing rainfall runoff in an urban area. From the analysis of field experiments, grass swale showed the significant rainfall runoff retention in different rain events. Grass swale markedly reduced total rainfall runoff volume and peak flow during the small storm events of intensity about 30 mm/h. From the analysis, on average rainfall runoff retention from the grass swale was found around 40 to 75% during the various small rain events. From the results, we can say that grass swale is a stormwater mitigation practice which can help avoid flash flooding problems in urban areas. PMID:29547567

Responses of Spartina alterniflora to Multiple Stressors ...

EPA Pesticide Factsheets

Coastal wetlands, well recognized for their ecosystem services, have faced many threats throughout the United States and elsewhere. Managers require good information on responses of wetlands to the combined stressors that these habitats experience, or may in the future as a result of climate change, and few studies have explored the effect of multiple stressors on wetlands. We conducted a 4-month mesocosm study to analyze the multiple stressor effects of precipitation changes, sea level rise, and eutrophication on the salt marsh plant Spartina alterniflora. Pots containing plants in a soil matrix were positioned in tanks and received Narragansett Bay (RI) water. The mesocosms simulated three precipitation levels (ambient daily rain, biweekly storm, and drought); three elevation levels, low (15 cm below mean high water (MHW)), middle (MHW), and high (15 cm above MHW); and two nutrient enrichment levels (unenriched and nutrient-enriched bay water). Our results demonstrate storm and drought stressors led to significantly less above- and belowground biomass than those in ambient rain conditions. Plants that were flooded at the low elevation had less belowground biomass, fine roots, and S. alterniflora shoots. Nutrients had no detectable effect on total above- and belowground biomass, but the enriched pots had higher stem counts and more fine roots than unenriched pots, in addition to greater CO2 emission rates. However, the unenriched pots had significantly more co

Evaluating the Capability of Grass Swale for the Rainfall Runoff Reduction from an Urban Parking Lot, Seoul, Korea.

PubMed

Shafique, Muhammad; Kim, Reeho; Kyung-Ho, Kwon

2018-03-16

This field study elaborates the role of grass swale in the management of stormwater in an urban parking lot. Grass swale was constructed by using different vegetations and local soil media in the parking lot of Mapu-gu Seoul, Korea. In this study, rainfall runoff was first retained in soil and the vegetation layers of the grass swale, and then infiltrated rainwater was collected with the help of underground perforated pipe, and passed to an underground storage trench. In this way, grass swale detained a large amount of rainwater for a longer period of time and delayed peak discharge. In this field study, various real storm events were monitored and the research results were analyzed to evaluate the performance of grass swale for managing rainfall runoff in an urban area. From the analysis of field experiments, grass swale showed the significant rainfall runoff retention in different rain events. Grass swale markedly reduced total rainfall runoff volume and peak flow during the small storm events of intensity about 30 mm/h. From the analysis, on average rainfall runoff retention from the grass swale was found around 40 to 75% during the various small rain events. From the results, we can say that grass swale is a stormwater mitigation practice which can help avoid flash flooding problems in urban areas.

Floodplain rehabilitation as a hedge against hydroclimatic uncertainty in a migration corridor of threatened steelhead.

PubMed

Boughton, David A; Pike, Andrew S

2013-12-01

A strategy for recovering endangered species during climate change is to restore ecosystem processes that moderate effects of climate shifts. In mid-latitudes, storm patterns may shift their intensity, duration, and frequency. These shifts threaten flooding in human communities and reduce migration windows (conditions suitable for migration after a storm) for fish. Rehabilitation of historic floodplains can in principle reduce these threats via transient storage of storm water, but no one has quantified the benefit of floodplain rehabilitation for migrating fish, a widespread biota with conservation and economic value. We used simple models to quantify migration opportunity for a threatened migratory fish, steelhead (Oncorhynchus mykiss), in an episodic rain-fed river system, the Pajaro River in central California. We combined flow models, bioenergetic models, and existing climate projections to estimate the sensitivity of migration windows to altered storm patterns under alternate scenarios of floodplain rehabilitation. Generally, migration opportunities were insensitive to warming, weakly sensitive to duration or intensity of storms, and proportionately sensitive to frequency of storms. The rehabilitation strategy expanded migration windows by 16-28% regardless of climate outcomes. Warmer conditions raised the energy cost of migrating, but not enough to matter biologically. Novel findings were that fewer storms appeared to pose a bigger threat to migrating steelhead than warmer or smaller storms and that floodplain rehabilitation lessened the risk from fewer or smaller storms across all plausible hydroclimatic outcomes. It follows that statistical downscaling methods may mischaracterize risk, depending on how they resolve overall precipitation shifts into changes of storm frequency as opposed to storm size. Moreover, anticipating effects of climate shifts that are irreducibly uncertain (here, rainfall) may be more important than anticipating effects of relatively predictable changes such as warming. This highlights a need to credibly identify strategies of ecosystem rehabilitation that are robust to uncertainty. Rehabilitación de Planicies Inundables como Cerco contra la Incertidumbre Hidroclimática en un Corredor Migratorio de Oncorhynchus mykiss, Especie Amenazada. © 2013 Society for Conservation Biology No claim to original US government works.

The case for a southeastern Australian Dust Bowl, 1895-1945

NASA Astrophysics Data System (ADS)

Cattle, Stephen R.

2016-06-01

Australia has an anecdotal history of severe wind erosion and dust storm activity, but there has been no lasting public perception of periods of extreme dust storm activity in this country, such as that developed in the USA following the Dust Bowl of the 1930s. Newspaper accounts of droughts and dust storms in southeastern (SE) Australia between 1895 and 1945 suggest that, at various times, the scale of these events was comparable to those experienced in the USA Dust Bowl. During this 50-year period, average annual rainfall values in this region were substantially below long-term averages, air temperatures were distinctly warmer, marginal lands were actively cropped and grazed, and rabbits were a burgeoning grazing pest. From the beginning of the Federation Drought of 1895-1902, dust storm activity increased markedly, with the downwind coastal cities of Sydney and Melbourne experiencing dust hazes, dust storms and falls of red rain relatively regularly. Between 1935 and 1945, Sydney and Melbourne received ten and nine long-distance dust events, respectively, with the years of 1938 and 1944/45 being the most intensely dusty. Entire topsoil horizons were blown away, sand drift was extreme, and crops and sheep flocks were destroyed. Although these periods of extreme dust storm activity were not as sustained as those experienced in the USA in the mid-1930s, there is a strong case to support the contention that SE Australia experienced its own extended, somewhat episodic version of a Dust Bowl, with a similar combination of causal factors and landscape effects.

Influence of land use on the quantity and quality of runoff along Israel's coastal strip

NASA Astrophysics Data System (ADS)

Goldshleger, Naftaly; Asaf, Lior; Maor, Alon; Garzuzi, Jamil Jamil

2013-04-01

This study presents an analysis of the quantity and quality of urban runoff from various land uses by remote-sensing and GIS technology coupled with hydrological and chemical monitoring. The study areas were located in the cities of Herzliya and Ra'anana, in Israel's coastal plain, where extensive urbanization has taken place over the last 30 years. Land uses in urban basins were analyzed; rain and runoff were measured and sampled at measurement stations representing different land uses (residential, industrial, commercial, roads, gas station). The aim was to analyze land uses by different remote-sensing and GIS techniques, to evaluate the quality and quantity of urban storm water from various land uses, and to verify a method for predicting the impact of urban land uses on quantity and quality of urban storm water. The quality of urban storm water from residential areas was generally very high, and the water is suitable for reuse or direct recharge into the local aquifer. In light of the serious state of the Israeli water sector and the large amounts of unused runoff produced by Israel's cities, together with the high quality of urban storm water drained from the residential areas, it is important to exploit this water source

Priority pollutants in urban stormwater: part 1 - case of separate storm sewers.

PubMed

Zgheib, Sally; Moilleron, Régis; Chebbo, Ghassan

2012-12-15

Organic and mineral pollutants have become part of today's urban environment. During a rain event, stormwater quality as well as the corresponding contaminant loads is affected by both atmospheric deposition and the various types of impervious surfaces (roads, rooftops, parking lots etc.) on which runoff occurs. This study provides results on stormwater pollution in Paris and its suburbs from three separate storm sewers (n=20 samples). These results show that the stormwater had been contaminated by 55 chemical substances out of the 88 investigated. A particular attention was given to stormwater particle contamination. Concentrations are provided for: metals, PAHs, PCBs, organotins, alkylphenols, phthalates, pesticides, and VOCs. Our findings are among the first available in the literature since the relevant analyses were all conducted on both the particulate (P) and dissolved (D) phases. For most substances, particles from the three storm sewers were more heavily contaminated than dredged sediments and settleable particles from the Seine River. As a consequence of this finding, the release of untreated stormwater discharges may impact the receiving waters and contribute to sediment contamination. Copyright © 2011 Elsevier Ltd. All rights reserved.

Seasonal Variability of Precipitation Extremes in New York City

NASA Astrophysics Data System (ADS)

Polanco, W.

2016-12-01

Precipitation extremes can have very important impacts, and it is not known as to how precipitation extremes might change with global warming. New York City is located in the mid-latitude region where there are specific storms that can cause precipitation extremes, predominantly, hurricanes, extratropical cyclones, and quasi-linear convective systems. These storms preferentially occur during different seasons. Therefore, to understand how these different storms relate to precipitation extremes, this study examines NYC precipitation extremes per season. First, NOAA weather station data from January 1979 to December 2014 from the three NYC airports (JFK, LaGuardia and Newark) will be analyzed to derive the climatology, the counts of non-rain events, and the counts of extreme precipitation events. Next, a multi-station average will be used to compare the precipitation events that occur in Spring, Summer, and Fall. The precipitation strength will be compared as well as the temperature anomalies for each season. Then, using reanalysis, composites of the sea level pressure and temperature fields will be calculated for the top events from each season.

Rainfall and runoff quantity and quality data collected at four urban land-use catchments in Fresno, California, October 1981-April 1983

USGS Publications Warehouse

Oltmann, R.N.; Guay, J.R.; Shay, J.M.

1987-01-01

Data were collected as part of the National Urban Runoff Program to characterize urban runoff in Fresno, California. Rainfall-runoff quantity and quality data are included along with atmospheric dry-deposition and street-surface particulate quality data. The data are presented in figures and tables that reflect four land uses: industrial, single-dwelling residential, multiple-dwelling residential, and commercial. A total of 255 storms were monitored for rainfall and runoff quantity. Runoff samples from 112 of these storms were analyzed for physical, organic, inorganic, and biological constituents. The majority of the remaining storms have pH and specific conductance data only. Ninety-two composite rain samples were collected. Of these, 63 were analyzed for physical, inorganic, and (or) organic constituents. The remaining rainfall samples have pH and specific conductance data only. Nineteen atmospheric deposition and 21 street-particulate samples were collected and analyzed for inorganic and organic constituents. The report also details equipment utilization and operation, and discusses data collection methods. (USGS)

A review of the bioretention system for sustainable storm water management in urban areas

NASA Astrophysics Data System (ADS)

Shafique, Muhammad

2016-10-01

Bioretention basins/rain garden is a very suitable low-impact development (LID) practice for storm water management around the globe. By using this practice in urban areas, flash flooding problems can be decreased and the environment of an area can be improved. The concept of bioretention was introduced a few decades ago and has been proven to be the best management practice (BMP) for storm water in urban areas. Due to urbanisation, natural surface areas are converted into hard surfaces such as roads, through which water cannot infiltrate into the ground. Due to this, infiltration decreases and surface run-off increases, which causes depletion of ground water continuously. In this study, we mainly explain the bioretention concept and its function as derived from different studies. This review includes different scientists' results for the performance of the bioretention system at different locations. A summary of the research findings by different scientists on the performance of bioretention systems is also provided, including the hydrologic and water quality performances. Finally, future work necessary to enhance the performance and widespread use of bioretention systems is also explained.

Losses Assessment of Crops due to Typhoon Disaster in China Coastal Areas —— A Case Study of Zhanjiang City, Guangdong Province

NASA Astrophysics Data System (ADS)

Mo, W.; Fang, W.

2015-12-01

Vulnerability which quantifies the loss ratio under different hazard intensity is an important feature of the natural disaster system and has important significance to natural disaster risk assessment. Agriculture is an outdoor industry with high risk of meteorological disasters. The strong winds, heavy rain and storm surge are main typhoon hazard factors to crops. To provide a quantitative research method for the loss evaluation of crops due to typhoon disaster we first revised two vulnerability curves for crops under comprehensive intensity of typhoon based on the simulated hazard data and loss data related to historical typhoon events landing on China from 1949 to 2014；and then established a storm surge vulnerability matrix of crops regarding Zhanjiang City of Guangdong Province as the study area ; finally, we put forward three storm surge fragility curves for crops representing different states of loss. The results can effectively describe the typhoon vulnerability for crops in China coastal areas so as to provide the input to post-disaster loss assessments and catastrophe modeling applications.

Characteristics of peak streamflows and extent of inundation in areas of West Virginia and southwestern Virginia affected by flooding, June 2016

USGS Publications Warehouse

Austin, Samuel H.; Watson, Kara M.; Lotspeich, R. Russell; Cauller, Stephen J.; White , Jeremy S.; Wicklein, Shaun M.

2017-11-17

Heavy rainfall occurred across central and southern West Virginia in June 2016 as a result of repeated rounds of torrential thunderstorms. The storms caused major flooding and flash flooding in central and southern West Virginia with Kanawha, Fayette, Nicholas, and Greenbrier Counties among the hardest hit. Over the duration of the storms, from 8 to 9.37 inches of rain was reported in areas in Greenbrier County. Peak streamflows were the highest on record at 7 locations, and streamflows at 18 locations ranked in the top five for the period of record at U.S. Geological Survey streamflow-gaging stations used in this study. Following the storms, U.S. Geological Survey hydrographers identified and documented 422 high-water marks in West Virginia, noting location and height of the water above land surface. Many of these high-water marks were used to create flood-inundation maps for selected communities of West Virginia that experienced flooding in June 2016. Digital datasets of the inundation areas, mapping boundaries, and water depth rasters are available online.

The Role of Fog in Ecosystem Hydrology: Initial Results from Investigations Using Stable Isotopes of Water in Hawaiian Cloud Forests

NASA Astrophysics Data System (ADS)

Scholl, M. A.; Gingerich, S. B.; Giambelluca, T. W.; Nullet, M. A.; Loope, L. L.

2002-05-01

The role of fog drip in cloud forest ecosystems is being investigated at two sites, one each on the windward and leeward sides of East Maui, Hawaii. The study involves using the different isotopic signatures of fog (cloud water) and rain to trace fog through the forest water cycle, as well as comparing relative amounts of fog, rain, and throughfall. At each site, volume of rain, fog plus rain, and throughfall is recorded hourly. Stable isotope samples of rain, fog, soil water, stream water, and tree sap are collected monthly, and each site has a visibility sensor and weather station. The windward site, at 1950 m altitude, is enveloped by orographic clouds under trade wind conditions almost every day. This site is near the upper boundary of extensive forested mountain slopes that are a major watershed for the island. Volume data suggest that fog drip (compared to rain as measured by a standard gage) contributes substantially to the forest water budget on the windward side. Tree sap deuterium composition was consistently similar to fog composition for samples analyzed thus far, while soil water was isotopically lighter, possibly reflecting a mixture of fog with rain or shallow groundwater. The leeward site, at 1220 m, is often in a cloud bank under trade wind conditions. During the summer the major source of precipitation is cloud water; rainfall generally occurs during winter storms. Scattered cloud forest remnants persist at this site despite degradation of extensive native forest by ungulate browsing, plant invasion, and fire. Here, fog drip was a smaller proportion of the total precipitation than at the windward site, but exceeded rainfall for some precipitation events. Unlike the windward site, tree sap and soil water had similar isotopic composition. The information gained from this study underscores the importance of trees and shrubs in extracting cloud water that contributes to soil moisture, groundwater recharge, and stream flow in watersheds.

Lightning location relative to storm structure in a supercell storm and a multicell storm

NASA Technical Reports Server (NTRS)

Ray, Peter S.; Macgorman, Donald R.; Rust, W. David; Taylor, William L.; Rasmussen, Lisa Walters

1987-01-01

Relationships between lightning location and storm structure are examined for one radar volume scan in each of two mature, severe storms. One of these storms had characteristics of a supercell storm, and the other was a multicell storm. Data were analyzed from dual-Doppler radar and dual-VHF lightning-mapping systems. The distributions of VHF impulse sources were compared with radar reflectivity, vertical air velocity, and their respective gradients. In the supercell storm, lightning tended to occur along streamlines above and down-shear of the updraft and reflectivity cores; VHF impulse sources were most concentrated in reflectivities between 30 and 40 dBZ and were distributed uniformly with respect to updraft speed. In the multicell storm, on the other hand, lightning tended to coincide with the vertical reflectivity and updraft core and with the diverging streamlines near the top of the storm. The results suggest that the location of lightning in these severe storms were most directly associated with the wind field structure relative to updraft and reflectivity cores. Since the magnitude and vertical shear of the environmental wind are fundamental in determining the reflectivity and wind field structure of a storm, it is suggested that these environmental parameters are also fundamental in determining lightning location.

KSC-06pd1038

NASA Image and Video Library

2006-06-13

KENNEDY SPACE CENTER, FLA. - During a break in the rain storms from Tropical Storm Alberto, the STS-121 crew arrives at NASA's Kennedy Space Center aboard a Grumman G2 aircraft to take part in a Terminal Countdown Demonstration Test, or TCDT. Greeting the crew is Shuttle Launch Director Mike Leinbach, here shaking hands with Mission Specialist Thomas Reiter, who represents the European Space Agency. Other crew members are Mission Commander Steven Lindsey, Pilot Mark Kelly, and Mission Specialists Piers Sellers, Michael Fossum, Lisa Nowak and Stephanie Wilson. Over several days, the crew will practice emergency egress from the pad and suit up in their orange flight suits for the simulated countdown to launch. Space Shuttle Discovery is designated to launch July 1 on mission STS-121. It will carry supplies to the International Space Station. Photo credit: NASA/Kim Shiflett

Thunderstorms and flooding of August 17, 2007, with a context provided by a history of other large storm and flood events in the Black Hills area of South Dakota

USGS Publications Warehouse

Driscoll, Daniel G.; Bunkers, Matthew J.; Carter, Janet M.; Stamm, John F.; Williamson, Joyce E.

2010-01-01

The Black Hills area of western South Dakota has a history of damaging flash floods that have resulted primarily from exceptionally strong rain-producing thunderstorms. The best known example is the catastrophic storm system of June 9-10, 1972, which caused severe flooding in several major drainages near Rapid City and resulted in 238 deaths. More recently, severe thunderstorms caused flash flooding near Piedmont and Hermosa on August 17, 2007. Obtaining a thorough understanding of peak-flow characteristics for low-probability floods will require a comprehensive long-term approach involving (1) documentation of scientific information for extreme events such as these; (2) long-term collection of systematic peak-flow records; and (3) regional assessments of a wide variety of peak-flow information. To that end, the U.S. Geological Survey cooperated with the South Dakota Department of Transportation and National Weather Service to produce this report, which provides documentation regarding the August 17, 2007, storm and associated flooding and provides a context through examination of other large storm and flood events in the Black Hills area. The area affected by the August 17, 2007, storms and associated flooding generally was within the area affected by the larger storm of June 9-10, 1972. The maximum observed 2007 precipitation totals of between 10.00 and 10.50 inches occurred within about 2-3 hours in a small area about 5 miles west of Hermosa. The maximum documented precipitation amount in 1972 was 15.0 inches, and precipitation totals of 10.0 inches or more were documented for 34 locations within an area of about 76 square miles. A peak flow of less than 1 cubic foot per second occurred upstream from the 2007 storm extent for streamflow-gaging station 06404000 (Battle Creek near Keystone); whereas, the 1972 peak flow of 26,200 cubic feet per second was large, relative to the drainage area of only 58.6 square miles. Farther downstream along Battle Creek, a 2007 flow of 26,000 cubic feet per second was generated entirely within an intervening drainage area of only 44.4 square miles. An especially large flow of 44,100 cubic feet per second was documented for this location in 1972. The 2007 peak flow of 18,600 cubic feet per second for Battle Creek at Hermosa (station 06406000) was only slightly smaller than the 1972 peak flow of 21,400 cubic feet per second. Peak-flow values from 2007 for three sites with small drainage areas (less than 1.0 square mile) plot close to a regional envelope curve, indicating exceptionally large flow values, relative to drainage area. Physiographic factors that affect flooding in the area were examined. The limestone headwater hydrogeologic setting (within and near the Limestone Plateau area on the western flank of the Black Hills) has distinctively suppressed peak-flow characteristics for small recurrence intervals. Uncertainty is large, however, regarding characteristics for large recurrence intervals (low-probability floods) because of a dearth of information regarding the potential for generation of exceptionally strong rain-producing thunderstorms. In contrast, the greatest potential for exceptionally damaging floods is around the flanks of the rest of the Black Hills area because of steep topography and limited potential for attenuation of flood peaks in narrow canyons. Climatological factors that affect area flooding also were examined. Area thunderstorms are largely terrain-driven, especially with respect to their requisite upward motion, which can be initiated by orographic lifting effects, thermally enhanced circulations, and obstacle effects. Several other meteorological processes are influential in the development of especially heavy precipitation for the area, including storm cell training, storm anchoring or regeneration, storm mergers, supercell development, and weak upper-level air flow. A composite of storm total precipitation amounts for 13 recent individual storm events indicates

Observations During GRIP from HIRAD: Images of C-Band Brightness Temperatures and Ocean Surface Wind Speed and Rain Rate

NASA Technical Reports Server (NTRS)

Miller, Timothy L.; James, M. W.; Jones, W. L.; Ruf, C. S.; Uhlhorn, E. W.; Biswas, S.; May, C.; Shah, G.; Black, P.; Buckley, C. D.

2012-01-01

HIRAD (Hurricane Imaging Radiometer) flew on the WB-57 during NASA s GRIP (Genesis and Rapid Intensification Processes) campaign in August - September of 2010. HIRAD is a new C-band radiometer using a synthetic thinned array radiometer (STAR) technology to obtain cross-track resolution of approximately 3 degrees, out to approximately 60 degrees to each side of nadir. By obtaining measurements of emissions at 4, 5, 6, and 6.6 GHz, observations of ocean surface wind speed and rain rate can be inferred. This technique has been used for many years by precursor instruments, including the Stepped Frequency Microwave Radiometer (SFMR), which has been flying on the NOAA and USAF hurricane reconnaissance aircraft for several years. The advantage of HIRAD over SFMR is that HIRAD can observe a +/- 60-degree swath, rather than a single footprint at nadir angle. Results from the flights during the GRIP campaign will be shown, including images of brightness temperatures, wind speed, and rain rate. To the extent possible, comparisons will be made with observations from other instruments on the GRIP campaign, for which HIRAD observations are either directly comparable or are complementary. Features such as storm eye and eyewall, location of vortex wind and rain maxima, and indications of dynamical features such as the merging of a weaker outer wind/rain maximum with the main vortex may be seen in the data. Potential impacts on operational ocean surface wind analyses and on numerical weather forecasts will also be discussed.

Satellite Sees Major Winter Storm Ready to Wallop Mid-Atlantic

NASA Image and Video Library

2014-03-02

A major winter storm is poised to wallop the Mid-Atlantic and bring large amounts of snow to cities including Baltimore, Md., Washington, D.C. area on March 2 and 3, according to NOAA's National Weather Service. NOAA's GOES-East satellite captured this image of the clouds associated with the winter storm as it continued moving east toward those cities. On March 2, the National Weather Prediction Center in College Park, Md. noted that there is a slight risk for severe thunderstorms over parts of the western Gulf Coast and the Lower Mississippi Valley as a result of the southern portion of the system. The update at 7 a.m. EST noted that freezing rain/sleet is possible over parts of the lower Mississippi Valley and parts of the central Appalachians, while eastern Texas and the lower Mississippi Valley into the Ohio Valley are expected to experience heavy rain. The NWS Short Range Forecast Discussion stated "A strong storm over the Southern Plains/Lower Mississippi Valley will advance northeastward along a quasi-stationary front to off the Southern Mid-Atlantic Coast by Monday evening. Moisture from the Gulf of Mexico will overrun and pool along the associated front producing an area of snow extending from the Central Plains into the Northeast." The clouds are associated with a cold from that stretches from eastern Maine through Maryland and west into the Tennessee Valley. The low pressure center associated with the front was located over Arkansas. At NASA/NOAA's GOES Project at NASA's Goddard Space Flight Center in Greenbelt, Md. the cloud data from NOAA's GOES-East satellite were overlaid on a true-color image of land and ocean created by data from the Moderate Resolution Imaging Spectroradiometer or MODIS instrument that flies aboard NASA's Aqua and Terra satellites. Together, those data created the entire picture of the position of this major winter storm. GOES satellites provide the kind of continuous monitoring necessary for intensive data analysis. Geostationary describes an orbit in which a satellite is always in the same position with respect to the rotating Earth. This allows GOES to hover continuously over one position on Earth's surface, appearing stationary. As a result, GOES provide a constant vigil for the atmospheric "triggers" for severe weather conditions such as tornadoes, flash floods, hail storms and hurricanes. For updated information about the storm system, visit NOAA's NWS website: www.weather.gov For more information about GOES satellites, visit: www.goes.noaa.gov/ or goes.gsfc.nasa.gov/ Rob Gutro NASA Goddard Space Flight Center, Greenbelt, Md. NASA image use policy. NASA Goddard Space Flight Center enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission. Follow us on Twitter Like us on Facebook Find us on Instagram

Convective weather hazards in the Twin Cities Metropolitan Area, MN

NASA Astrophysics Data System (ADS)

Blumenfeld, Kenneth A.

This dissertation investigates the frequency and intensity of severe convective storms, and their associated hazards, in the Twin Cities Metropolitan Area (TCMA), Minnesota. Using public severe weather reports databases and high spatial density rain gauge data, annual frequencies and return-periods are calculated for tornadoes, damaging winds, large hail, and flood-inducing rainfall. The hypothesis that severe thunderstorms and tornadoes are less likely in the central TCMA than in surrounding areas also is examined, and techniques for estimating 100-year rainfall amounts are developed and discussed. This research finds that: (i) storms capable of significant damage somewhere within the TCMA recur annually (sometimes multiple times per year), while storms virtually certain to cause such damage recur every 2-3 years; (ii) though severe weather reports data are not amenable to classical comparative statistical testing, careful treatment of them suggests all types and intensity categories of severe convective weather have been and should continue to be approximately as common in the central TCMA as in surrounding areas; and (iii) applications of Generalized Extreme Value (GEV) statistics and areal analyses of rainfall data lead to significantly larger (25-50%) estimates of 100-year rainfall amounts in the TCMA and parts of Minnesota than those currently published and used for precipitation design. The growth of the TCMA, the popular sentiment that downtown areas somehow deter severe storms and tornadoes, and the prior underestimation of extreme rainfall thresholds for precipitation design, all act to enhance local susceptibility to hazards from severe convective storms.

Relative effects on a low-volume road system of landslides resulting from episodic storms in northern Idaho

USGS Publications Warehouse

McClelland, D.E.; Foltz, R.B.; Falter, C.M.; Wilson, W.D.; Cundy, T.; Schuster, R.L.; Saurbier, J.; Rabe, C.; Heinemann, R.

1999-01-01

In late November to early December 1995 and February 1996, northern Idaho was hit by heavy rains on a deep snowpack, resulting in two flood and landslide events of historic magnitude. Each of these storms was larger than the previous significant storm, which occurred in January 1974. A study was initiated by the U.S. Department of Agriculture Forest Service to survey and study the effects of the resultant landslides on the Clearwater National Forest, including the effects on the aquatic ecosystem. The results of this study were compared with the estimated average natural sediment resulting from landslides to evaluate the incremental impacts of these recent episodic landslides. They were also compared with the results of a study conducted on the landslides resulting from the January 1974 storm to determine if the landscape was responding more severely to large storms as a result of Forest Service management activities over the past 21 years. The general results of this study indicate that, of the Forest Service management activities, roads are the major contributor; however, they contribute less sediment than natural landslides. The total resultant sediment appears to be within the transport capacity of the aquatic system, and the landslide response in 1974 was similar to the 1995-1996 response. The results of the aquatic ecosystem study were generally mixed, with some habitat parameters indicating degradation, some unchanged, and some improved as a result of the flooding or flooding with landslide sediment.

Geomorphic effects of large debris flows and flash floods, northern Venezuela, 1999

USGS Publications Warehouse

Larsen, M.C.; Wieczorek, G.F.

2006-01-01

A rare, high-magnitude storm in northern Venezuela in December 1999 triggered debris flows and flash floods, and caused one of the worst natural disasters in the recorded history of the Americas. Some 15,000 people were killed. The debris flows and floods inundated coastal communities on alluvial fans at the mouths of a coastal mountain drainage network and destroyed property estimated at more than $2 billion. Landslides were abundant and widespread on steep slopes within areas underlain by schist and gneiss from near the coast to slightly over the crest of the mountain range. Some hillsides were entirely denuded by single or coalescing failures, which formed massive debris flows in river channels flowing out onto densely populated alluvial fans at the coast. The massive amount of sediment derived from 24 watersheds along 50 km of the coast during the storm and deposited on alluvial fans and beaches has been estimated at 15 to 20 million m3. Sediment yield for the 1999 storm from the approximately 200 km2 drainage area of watersheds upstream of the alluvial fans was as much as 100,000 m3/km2. Rapid economic development in this dynamic geomorphic environment close to the capital city of Caracas, in combination with a severe rain storm, resulted in the death of approximately 5% of the population (300,000 total prior to the storm) in the northern Venezuelan state of Vargas. ?? 2006 Gebru??der Borntraeger.

Assessing the Predictability of Convection using Ensemble Data Assimilation of Simulated Radar Observations in an LETKF system

NASA Astrophysics Data System (ADS)

Lange, Heiner; Craig, George

2014-05-01

This study uses the Local Ensemble Transform Kalman Filter (LETKF) to perform storm-scale Data Assimilation of simulated Doppler radar observations into the non-hydrostatic, convection-permitting COSMO model. In perfect model experiments (OSSEs), it is investigated how the limited predictability of convective storms affects precipitation forecasts. The study compares a fine analysis scheme with small RMS errors to a coarse scheme that allows for errors in position, shape and occurrence of storms in the ensemble. The coarse scheme uses superobservations, a coarser grid for analysis weights, a larger localization radius and larger observation error that allow a broadening of the Gaussian error statistics. Three hour forecasts of convective systems (with typical lifetimes exceeding 6 hours) from the detailed analyses of the fine scheme are found to be advantageous to those of the coarse scheme during the first 1-2 hours, with respect to the predicted storm positions. After 3 hours in the convective regime used here, the forecast quality of the two schemes appears indiscernible, judging by RMSE and verification methods for rain-fields and objects. It is concluded that, for operational assimilation systems, the analysis scheme might not necessarily need to be detailed to the grid scale of the model. Depending on the forecast lead time, and on the presence of orographic or synoptic forcing that enhance the predictability of storm occurrences, analyses from a coarser scheme might suffice.

KSC-08pd2551

NASA Image and Video Library

2008-09-05

CAPE CANAVERAL, Fla. – A minor effect of Tropical Storm Hanna as it passed Florida’s east coast, part of a panel on the Vehicle Assembly Building at NASA's Kennedy Space Center came off in a burst of high wind, causing minor damage to a UHF antenna on the roof of the Launch Control Center. The panel is on the southeast corner of the VAB. Hanna kept well offshore, bearing only bursts of rain and wind along the coastline as it moved north. Photo credit: NASA/Jack Pfaller

Rail and Motor Outloading Capability Study, Fort Chaffee, Arkansas,

DTIC Science & Technology

1978-11-01

instructors at Fort Eustis, Virginia, indicated that, to avoid wasted man - hours, there should be no more than eight men per crew, regardless of experience...level, total men per Man has to walk to front of vehicle as guide vehicle and to straighten bridge PL’s. Delays if all vehicles not at site at loading...vehicle (Storm, rain not included in total time) MILVAN married together 6-8 Some older cars have trailer hitches which Some 20-ft semis and man crew

February 2015 Leaves Its Mark on the Eastern U.S.

NASA Image and Video Library

2015-03-04

Freezing rain is in the forecast from Texas to the mid-Mississippi Valley and into the Carolinas with temperatures 20-40 degrees below normal across parts of the central and southern U.S. on Friday, extending February's icy grip on the eastern half of the U.S. This image from the Suomi NPP satellite's VIIRS instrument shows the snow cover left by February's series of east coast storms, taken around 1830Z on February 27, 2015. Credit: NASA/NOAA/NPP/VIIRS Via: NASA Earth Observatory

Satellite Eyes New England Winter Storm Breaking Records

NASA Image and Video Library

2015-02-09

Another large snowstorm affecting New England was dropping more snow on the region and breaking records on February 9, as NOAA's GOES-East satellite captured an image of the clouds associated with the storm system. On Feb. 9, NOAA's National Weather Service in Boston, Massachusetts noted that "The 30-day snowfall total at Boston ending 7 a.m. this morning is 61.6 inches. This exceeds the previous maximum 30 day snowfall total on record at Boston, which was 58.8 inches ending Feb 7 1978." The GOES-East image was created by NASA/NOAA's GOES Project at NASA's Goddard Space Flight Center in Greenbelt, Maryland. It showed a blanket of clouds over the U.S. northeast that stretched down to the Mid-Atlantic where there was no snow on the ground in Washington, D.C. NOAA's National Weather Service Weather Prediction Center provided a look at the extent of the storm system and noted "Heavy snow will impact portions of New York State and New England as the new week begins. Freezing rain will spread from western Pennsylvania to Long Island, with rain for the mid-Atlantic states." The low pressure area bringing the snow to the northeast was located in central Pennsylvania. A cold front extended southward from the low across the Tennessee Valley while a stationary boundary extended eastward from the low across the central mid-Atlantic. To create the image, NASA/NOAA's GOES Project takes the cloud data from NOAA's GOES-East satellite and overlays it on a true-color image of land and ocean created by data from the Moderate Resolution Imaging Spectroradiometer, or MODIS, instrument that flies aboard NASA's Aqua and Terra satellites. Together, those data created the entire picture of the storm. NOAA's GOES satellites provide the kind of continuous monitoring necessary for intensive data analysis. Geostationary describes an orbit in which a satellite is always in the same position with respect to the rotating Earth. This allows GOES to hover continuously over one position on Earth's surface, appearing stationary. As a result, GOES provide a constant vigil for the atmospheric triggers for severe weather conditions such as tornadoes, flash floods, hail storms and hurricanes. For updated information about the storm system, visit NOAA's NWS website: www.weather.gov For more information about GOES satellites, visit: www.goes.noaa.gov/ or goes.gsfc.nasa.gov/ Rob Gutro NASA's Goddard Space Flight Center Credit: NOAA/NASA GOES Project NASA image use policy. NASA Goddard Space Flight Center enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission. Follow us on Twitter Like us on Facebook Find us on Instagram

Coupled effects of wind-storms and drought on tree mortality across 115 forest stands from the Western Alps and the Jura mountains.

PubMed

Csilléry, Katalin; Kunstler, Georges; Courbaud, Benoît; Allard, Denis; Lassègues, Pierre; Haslinger, Klaus; Gardiner, Barry

2017-12-01

Damage due to wind-storms and droughts is increasing in many temperate forests, yet little is known about the long-term roles of these key climatic factors in forest dynamics and in the carbon budget. The objective of this study was to estimate individual and coupled effects of droughts and wind-storms on adult tree mortality across a 31-year period in 115 managed, mixed coniferous forest stands from the Western Alps and the Jura mountains. For each stand, yearly mortality was inferred from management records, yearly drought from interpolated fields of monthly temperature, precipitation and soil water holding capacity, and wind-storms from interpolated fields of daily maximum wind speed. We performed a thorough model selection based on a leave-one-out cross-validation of the time series. We compared different critical wind speeds (CWSs) for damage, wind-storm, and stand variables and statistical models. We found that a model including stand characteristics, drought, and storm strength using a CWS of 25 ms -1 performed the best across most stands. Using this best model, we found that drought increased damage risk only in the most southerly forests, and its effect is generally maintained for up to 2 years. Storm strength increased damage risk in all forests in a relatively uniform way. In some stands, we found positive interaction between drought and storm strength most likely because drought weakens trees, and they became more prone to stem breakage under wind-loading. In other stands, we found negative interaction between drought and storm strength, where excessive rain likely leads to soil water saturation making trees more susceptible to overturning in a wind-storm. Our results stress that temporal data are essential to make valid inferences about ecological impacts of disturbance events, and that making inferences about disturbance agents separately can be of limited validity. Under projected future climatic conditions, the direction and strength of these ecological interactions could also change. © 2017 John Wiley & Sons Ltd.

Assessing health impacts of the December 2013 Ice storm in Ontario, Canada.

PubMed

Rajaram, Nikhil; Hohenadel, Karin; Gattoni, Laera; Khan, Yasmin; Birk-Urovitz, Elizabeth; Li, Lennon; Schwartz, Brian

2016-07-11

Ice, or freezing rain storms have the potential to affect human health and disrupt normal functioning of a community. The purpose of this study was to assess acute health impacts of an ice storm that occurred in December 2013 in Toronto, Ontario, Canada. Data on emergency department visits were obtained from the National Ambulatory Care Reporting System. Rates of visits in Toronto during the storm period (December 21, 2013 - January 1, 2014) were compared to rates occurring on the same dates in the previous five years (historical comparison) and compared to those in a major unaffected city, Ottawa, Ontario (geographic comparison). Overall visits and rates for three categories of interest (cardiac conditions, environmental causes and injuries) were assessed. Rate ratios were calculated using Poisson regression with population counts as an offset. Absolute counts of carbon monoxide poisoning were compared descriptively in a sub-analysis. During the 2013 storm period, there were 34 549 visits to EDs in Toronto (12.46 per 1000 population) compared with 10 794 visits in Ottawa (11.55 per 1000 population). When considering year and geography separately, rates of several types of ED visits were higher in the storm year than in previous years in both Toronto and Ottawa. Considering year and geography together, rates in the storm year were higher for overall ED visits (RR: 1.10, 95 % CI: 1.09-1.11) and for visits due to environmental causes (RR: 2.52, 95 % CI: 2.21-2.87) compared to previous years regardless of city. For injuries, visit rates were higher in the storm year in both Toronto and Ottawa, but the increase in Toronto was significantly greater than the increase in Ottawa, indicating a significant interaction between geography and year (RR: 1.23, 95 % CI: 1.16-1.30). This suggests that the main health impact of the 2013 Ice Storm was an increase in ED visits for injuries, while other increases could have been due to severe weather across Ontario at that time. This study is one of the first to use a population-level database and regression modeling of emergency visit codes to identify acute impacts resulting from ice storms.

Tropical Storm Yagi off Japan

NASA Image and Video Library

2017-12-08

On Tuesday, June 11, 2013 Tropical Storm Yagi spun in the North Pacific Ocean just south of Japan. The Moderate Resolution Imaging Spectroradiometer (MODIS) aboard NASA’s Aqua satellite captured this beautiful true-color image of the storm on that same date at 4:10 UTC (1:10 p.m. Japan local time). The image shows a clear apostrophe-shaped cyclone, with a closed eye and somewhat elliptical shape. The clouds associated with the northern fringes of the storm draped over southeastern coastal Japan, and a long “tail” (or band) of thunderstorms fed into the center from the south. Multispectral imagery also showed tight bands of thunderstorms wrapping into the center of the storm, although the building of thunderstorms was weakening around the center. Near the same time as the image was captured, the Joint Typhoon Warning Center announced that vertical wind shear was starting to take a toll on Yagi. Northwesterly wind shear had caused the system to tilt slightly with the upper-level center displaced about 20 nautical miles east of the low-level center. Tropical Storm Yagi developed from Tropical Depression 03W in the Western North Pacific Ocean on June 6, and intensified the weekend of June 8-9, when it reached Tropical Storm status and was given the name Yagi. Also known as Dante, the storm reached the maximum wind speeds on June 10 and 11, after which it began to weaken as it moved into cooler waters. On June 14, Yagi’s remnants passed about 200 miles south of Tokyo, and brought soaking rains to the coastline of Japan’s Honshu Island. Credit: NASA/GSFC/Jeff Schmaltz/MODIS Land Rapid Response Team NASA image use policy. NASA Goddard Space Flight Center enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission. Follow us on Twitter Like us on Facebook Find us on Instagram

Experimental Marvin Windshield Effects on Precipitation Records in Leadville, Colorado

USGS Publications Warehouse

Jarrett, Robert D.; Crow, Loren W.

1988-01-01

An evaluation of the Leadville, Colorado, precipitation records that include a reported record-breaking storm (and flood) at higher elevations in the Rocky Mountains has indicated that the use of an experimental Marvin windshield (designed to decrease the effects of wind on precipitation-gage catchment of snow during winter) resulted in substantially overregistered summer precipitation for 1919 to 1938. The July monthly precipitation for these years was over-registered by an average of 157 percent of the long-term July monthly precipitation at Leadville. The cause of the overregistration of precipitation was the almost 4-foot-top-diameter cone-shaped windshield that had the effect of 'funneling' hail and rain splash into the rain gage. Other nearby precipitation gages, which did not use this Marvin windshield, did not have this trend of increased precipitation for the same period. Streamflow records from the Leadville area also do not indicate an increase in streamflow from 1919 to 1938.

Satellite techniques yield insight into devastating rainfall from Hurricane Mitch

NASA Astrophysics Data System (ADS)

Ferraro, R.; Vicente, G.; Ba, M.; Gruber, A.; Scofield, R.; Li, Q.; Weldon, R.

Hurricane Mitch may prove to be one of the most devastating tropical cyclones to affect the western hemisphere. Heavy rains over Central America from October 28, 1998, to November 1, 1998, caused widespread flooding and mud slides in Nicaragua and Honduras resulting in thousands of deaths and missing persons. News reports indicated entire towns being swept away, destruction of national economies and infrastructure, and widespread disease in the aftermath of the storm, which some estimates suggested dropped as much as 1300 mm of rain.However, in view of the widespread damage it is difficult to determine the actual amounts and distribution of rainfall. More accurate means of determining the rainfall associated with Mitch are vital for diagnosing and understanding the evolution of this disaster and for developing new mitigation strategies for future tropical cyclones. Satellite data may prove to be a reliable resource for accurate rainfall analysis and have yielded apparently reliable figures for Hurricane Mitch.