Long-term trend of satellite-observed significant wave height and impact on ecosystem in the East/Japan Sea

NASA Astrophysics Data System (ADS)

Woo, Hye-Jin; Park, Kyung-Ae

2017-09-01

Significant wave height (SWH) data of nine satellite altimeters were validated with in-situ SWH measurements from buoy stations in the East/Japan Sea (EJS) and the Northwest Pacific Ocean. The spatial and temporal variability of extreme SWHs was investigated by defining the 90th, 95th, and 99th percentiles based on percentile analysis. The annual mean of extreme SWHs was dramatically increased by 3.45 m in the EJS, which is significantly higher than the normal mean of about 1.44 m. The spatial distributions of SWHs showed significantly higher values in the eastern region of the EJS than those in the western part. Characteristic seasonality was found from the time-series SWHs with high SWHs (>2.5 m) in winter but low values (<1 m) in summer. The trends of the normal and extreme (99th percentile) SWHs in the EJS had a positive value of 0.0056 m year-1 and 0.0125 m year-1, respectively. The long-term trend demonstrated that higher SWH values were more extreme with time during the past decades. The predominant spatial distinctions between the coastal regions in the marginal seas of the Northwest Pacific Ocean and open ocean regions were presented. In spring, both normal and extreme SWHs showed substantially increasing trends in the EJS. Finally, we first presented the impact of the long-term trend of extreme SWHs on the marine ecosystem through vertical mixing enhancement in the upper ocean of the EJS.

Extreme sea storm in the Mediterranean Sea. Trends during the 2nd half of the 20th century.

NASA Astrophysics Data System (ADS)

Pino, C.; Lionello, P.; Galati, M. B.

2009-04-01

Extreme sea storm in the Mediterranean Sea. Trends during the 2nd half of the 20th century Piero Lionello, University of Salento, piero.lionello@unisalento.it Maria Barbara Galati, University of Salento, mariabarbara.galati@unisalento.it Cosimo Pino, University of Salento, pino@le.infn.it The analysis of extreme Significant Wave Height (SWH) values and their trend is crucial for planning and managing coastal defences and off-shore activities. The analysis provided by this study covers a 44-year long period (1958-2001). First the WW3 (Wave Watch 3) model forced with the REMO-Hipocas regional model wind fields has been used for the hindcast of extreme SWH values over the Mediterranean basin with a 0.25 deg lat-lon resolution. Subsequently, the model results have been processed with an ad hoc software to detect storms. GEV analysis has been perfomed and a set of indicators for extreme SWH have been computed, using the Mann Kendall test for assessing statistical significance of trends for different parameter such as the number of extreme events, their duration and their intensity. Results suggest a transition towards weaker extremes and a milder climate over most of the Mediterranean Sea.

Validation of Cryosat-2 SAR Wind and Wave Products

NASA Astrophysics Data System (ADS)

Abdalla, Saleh; Dinardo, Salvatore; Benveniste, Jerome; Janssen, Peter

2016-08-01

Significant wave height (SWH) and surface wind speed (WS) products from the CryoSat-2 Synthetic Aperture Radar (SAR) Mode are validated against operational ECMWF atmospheric and wave model results in addition to available observations from buoys, platforms and other altimeters. The SAMOSA ocean model SAR data processed in the ESRIN G-POD service using SAR Versatile Altimetric Toolkit for Ocean Research & Exploitation (SARvatore). The data cover two geographic boxes: one in the northeast Atlantic Ocean extending from 32°N to 70°N and from 20°W to the prime meridian (NE Atlantic Box) for the period from 6 September 2010 to 30 June 2014 and the other is in eastern Pacific extending from 2.5°S to 25.5°S and from 160°W to 85°W (Pacific Box) for the period from 7 May 2012 to 30 June 2014. The amount of data is limited by the CryoSat SAR mode acquisition capability over ocean but high enough to ensure robustness and significance of the results (Sentinel-3 will operate in SAR mode over the whole ocean). The results show that the quality of both SWH and WS products is very high.

SWH trends and links to large scale teleconnection patterns in the Mediterranean Sea

NASA Astrophysics Data System (ADS)

Lionello, P.; Pino, C.; Galati, M. B.

2010-09-01

This study analyzes the SWH field in the Mediterranean Sea using a multidecadal simulations (1958-2001) carried out using the WAM (WAve Model) forced by the REMO-HIPOCAS wind fields. The simulations are validated against satellite altimeter data. Several mid-latitude patterns are linked to the SWH field in the Mediterranean. Considering the mean monthly SWH values, EA (Eastern Atlantic pattern) exerts the largest influence, while NAO and other patterns have a smaller but comparable effect. Severe SWH conditions have been characterized using the 95percentile of daily SWH maxima. NAO is important mainly for high SWH conditions in winter with significant correlation in December, January and March, but also EA, SCA (SCAndinavian) and EA-WR (Eastern Atlantic-Western Russia) play an important role. In general, both SWH high and mean values are modulated by several patterns, with an important variability in space and at monthly level so that no single pattern can be attributed a dominant role along the whole annual cycle and all the mentioned patterns are important for at least few months in the year. Significant trends of SWH are present only in sparse areas and suggest mostly a minor decrease of storm intensity, The statistics of extremes and high SWH values is substantially steady during the second half of the 20th century.

The wind sea and swell waves climate in the Nordic seas

NASA Astrophysics Data System (ADS)

Semedo, Alvaro; Vettor, Roberto; Breivik, Øyvind; Sterl, Andreas; Reistad, Magnar; Soares, Carlos Guedes; Lima, Daniela

2015-02-01

A detailed climatology of wind sea and swell waves in the Nordic Seas (North Sea, Norwegian Sea, and Barents Sea), based on the high-resolution reanalysis NORA10, developed by the Norwegian Meteorological Institute, is presented. The higher resolution of the wind forcing fields, and the wave model (10 km in both cases), along with the inclusion of the bottom effect, allowed a better description of the wind sea and swell features, compared to previous global studies. The spatial patterns of the swell-dominated regional wave fields are shown to be different from the open ocean, due to coastal geometry, fetch dimensions, and island sheltering. Nevertheless, swell waves are still more prevalent and carry more energy in the Nordic Seas, with the exception of the North Sea. The influence of the North Atlantic Oscillation on the winter regional wind sea and swell patterns is also presented. The analysis of the decadal trends of wind sea and swell heights during the NORA10 period (1958-2001) shows that the long-term trends of the total significant wave height (SWH) in the Nordic Seas are mostly due to swell and to the wave propagation effect.

Assessing wave climate trends in the Bay of Biscay through an intercomparison of wave hindcasts and reanalyses

NASA Astrophysics Data System (ADS)

Paris, F.; Lecacheux, S.; Idier, D.; Charles, E.

2014-09-01

The Bay of Biscay, located in the Northeast Atlantic Ocean, is exposed to energetic waves coming from the open ocean that have crucial effects on the coast. Knowledge of the wave climate and trends in this region are critical to better understand the last decade's evolution of coastal hazards and morphology and to anticipate their potential future changes. This study aims to characterize the long-term trends of the present wave climate over the second half of the twentieth century in the Bay of Biscay through a robust and homogeneous intercomparison of five-wave datasets (Corrected ERA-40 (C-ERA-40), ECMWF Reanalysis Interim (ERA-Interim), Bay Of Biscay Wave Atlas (BOBWA-10kH), ANEMOC, and Bertin and Dodet 2010)). The comparison of the quality of the datasets against offshore and nearshore measurements reveals that at offshore locations, global reanalyses slightly underestimate wave heights, while regional hindcasts overestimate wave heights, especially for the highest quantiles. At coastal locations, BOBWA-10kH is the dataset that compares the best with observations. Concerning long time-scale features, the comparison highlights that the main significant trends are similarly present in the five datasets, especially during summer for which there is an increase of significant wave heights and mean wave periods (up to +15 cm and +0.6 s over the period 1970-2001) as well as a southerly shift of wave directions (around -0.4° year-1). Over the same period, an increase of high quantiles of wave heights during the autumn season (around 3 cm year-1 for 90th quantile of significant wave heights (SWH90)) is also apparent. During winter, significant trends are much lower than during summer and autumn despite a slight increase of wave heights and periods during 1958-2001. These trends can be related to modifications in the wave-type occurrence. Finally, the trends common to the five datasets are discussed by analyzing the similarities with centennial trends issued from longer time-scale studies and exploring the various factors that could explain them.

Prediction of Significant Wave Heights in the Tropics at Sub-seasonal Time Scales

NASA Astrophysics Data System (ADS)

Kinter, J. L.; Shukla, R. P.; Shin, C. S.

2017-12-01

Skillfully predicting the 14-day mean significant wave height (SWH) forecasts at 3 weeks lead-time over the Western Pacific and Indian Oceans has been demonstrated using the WAVEWATCH-3 (WW3) model coupled to a modified version of the National Centers for Environmental Prediction (NCEP) Climate Forecast System, version 2 (CFSv2). In this paper, we present results on the effect of the Madden Julian Oscillation (MJO) events and El Niño and the Southern Oscillation (ENSO) on such predictions. Forecasts initialized with multiple ocean analyses in both January and May for 1979-2008 are evaluated. A significant anomaly correlation of predicted and observed SWH anomalies (SWHA) at 3 weeks lead-time is found over portions of the domain in both January and May cases. The model successfully predicts almost all the important features of the observed SWHA during El Niño events in January, including negative SWHA in the central Indian Ocean and northern western tropical Pacific, and positive SWHA over the southern Ocean and western Pacific. The model also reproduces the spatial pattern of the inverse relationship between SWHA and sea level pressure anomalies during both composite El Niño and La Niña events at 3 weeks lead-time. The model successfully predicts the sign and magnitude of SWHA in May over the Bay of Bengal and South China Sea in composites of phases 2 and 6 of MJO. The observed leading mode of SWHA in May and the third mode of SWHA in January are influenced by the combined effects of MJO and ENSO. Analysis of the mechanisms for these relationships is described.

Sub-seasonal prediction of significant wave heights over the Western Pacific and Indian Oceans, part II: The impact of ENSO and MJO

NASA Astrophysics Data System (ADS)

Shukla, Ravi P.; Kinter, James L.; Shin, Chul-Su

2018-03-01

This study evaluates the effect of El Niño and the Southern Oscillation (ENSO) and Madden Julian Oscillation (MJO) events on 14-day mean significant wave height (SWH) at 3 weeks lead time (Wk34) over the Western Pacific and Indian Oceans using the National Centers for Environmental Prediction (NCEP) Climate Forecast System, version 2 (CFSv2). The WAVEWATCH-3 (WW3) model is forced with daily 10m-winds predicted by a modified version of CFSv2 that is initialized with multiple ocean analyses in both January and May for 1979-2008. A significant anomaly correlation of predicted and observed SWH anomalies (SWHA) at Wk34 lead-time is found over portions of the domain, including the central western Pacific, South China Sea (SCS), Bay of Bengal (BOB) and southern Indian Ocean (IO) in January cases, and over BOB, equatorial western Pacific, the Maritime Continent and southern IO in May cases. The model successfully predicts almost all the important features of the observed composite SWHA during El Niño events in January, including negative SWHA in the central IO where westerly wind anomalies act on an easterly mean state, and positive SWHA over the southern Ocean (SO) where westerly wind anomalies act on a westerly mean state. The model successfully predicts the sign and magnitude of SWHA at Wk34 lead-time in May over the BOB and SCS in composites of combined phases-2-3 and phases-6-7 of MJO. The observed leading mode of SWHA in May and the third mode of SWHA in January are influenced by the combined effects of ENSO and MJO. Based on spatial and temporal correlations, the spatial patterns of SWHA in the model at Wk34 in both January and May are in good agreement with the observations over the equatorial western Pacific, equatorial and southern IO, and SO.

Inverse Regional Modeling with Adjoint-Free Technique

NASA Astrophysics Data System (ADS)

Yaremchuk, M.; Martin, P.; Panteleev, G.; Beattie, C.

2016-02-01

The ongoing parallelization trend in computer technologies facilitates the use ensemble methods in geophysical data assimilation. Of particular interest are ensemble techniques which do not require the development of tangent linear numerical models and their adjoints for optimization. These ``adjoint-free'' methods minimize the cost function within the sequence of subspaces spanned by a carefully chosen sets perturbations of the control variables. In this presentation, an adjoint-free variational technique (a4dVar) is demonstrated in an application estimating initial conditions of two numerical models: the Navy Coastal Ocean Model (NCOM), and the surface wave model (WAM). With the NCOM, performance of both adjoint and adjoint-free 4dVar data assimilation techniques is compared in application to the hydrographic surveys and velocity observations collected in the Adriatic Sea in 2006. Numerical experiments have shown that a4dVar is capable of providing forecast skill similar to that of conventional 4dVar at comparable computational expense while being less susceptible to excitation of ageostrophic modes that are not supported by observations. Adjoint-free technique constrained by the WAM model is tested in a series of data assimilation experiments with synthetic observations in the southern Chukchi Sea. The types of considered observations are directional spectra estimated from point measurements by stationary buoys, significant wave height (SWH) observations by coastal high-frequency radars and along-track SWH observations by satellite altimeters. The a4dVar forecast skill is shown to be 30-40% better than the skill of the sequential assimilaiton method based on optimal interpolation which is currently used in operations. Prospects of further development of the a4dVar methods in regional applications are discussed.

A rat model of hypohidrotic ectodermal dysplasia carries a missense mutation in the Edaradd gene

PubMed Central

2011-01-01

Background Hypohidrotic ectodermal dysplasia (HED) is a congenital disorder characterized by sparse hair, oligodontia, and inability to sweat. It is caused by mutations in any of three Eda pathway genes: ectodysplasin (Eda), Eda receptor (Edar), and Edar-associated death domain (Edaradd), which encode ligand, receptor, and intracellular adaptor molecule, respectively. The Eda signaling pathway activates NF-κB, which is central to ectodermal differentiation. Although the causative genes and the molecular pathway affecting HED have been identified, no curative treatment for HED has been established. Previously, we found a rat spontaneous mutation that caused defects in hair follicles and named it sparse-and-wavy (swh). Here, we have established the swh rat as the first rat model of HED and successfully identified the swh mutation. Results The swh/swh rat showed sparse hair, abnormal morphology of teeth, and absence of sweat glands. The ectoderm-derived glands, meibomian, preputial, and tongue glands, were absent. We mapped the swh mutation to the most telomeric part of rat Chr 7 and found a Pro153Ser missense mutation in the Edaradd gene. This mutation was located in the death domain of EDARADD, which is crucial for signal transduction and resulted in failure to activate NF-κB. Conclusions These findings suggest that swh is a loss-of-function mutation in the rat Edaradd and indicate that the swh/swh rat would be an excellent animal model of HED that could be used to investigate the pathological basis of the disease and the development of new therapies. PMID:22013926

Longitudinal analysis of standardized test scores of students in the Science Writing Heuristic approach

NASA Astrophysics Data System (ADS)

Chanlen, Niphon

The purpose of this study was to examine the longitudinal impacts of the Science Writing Heuristic (SWH) approach on student science achievement measured by the Iowa Test of Basic Skills (ITBS). A number of studies have reported positive impact of an inquiry-based instruction on student achievement, critical thinking skills, reasoning skills, attitude toward science, etc. So far, studies have focused on exploring how an intervention affects student achievement using teacher/researcher-generated measurement. Only a few studies have attempted to explore the long-term impacts of an intervention on student science achievement measured by standardized tests. The students' science and reading ITBS data was collected from 2000 to 2011 from a school district which had adopted the SWH approach as the main approach in science classrooms since 2002. The data consisted of 12,350 data points from 3,039 students. The multilevel model for change with discontinuity in elevation and slope technique was used to analyze changes in student science achievement growth trajectories prior and after adopting the SWH approach. The results showed that the SWH approach positively impacted students by initially raising science achievement scores. The initial impact was maintained and gradually increased when students were continuously exposed to the SWH approach. Disadvantaged students who were at risk of having low science achievement had bigger benefits from experience with the SWH approach. As a result, existing problematic achievement gaps were narrowed down. Moreover, students who started experience with the SWH approach as early as elementary school seemed to have better science achievement growth compared to students who started experiencing with the SWH approach only in high school. The results found in this study not only confirmed the positive impacts of the SWH approach on student achievement, but also demonstrated additive impacts found when students had longitudinal experiences with the approach. By engaging in the argument-based classrooms where teachers value students' prior knowledge, encourage students to take control of their learning, and provide non-threatening environment for students to developing big ideas through negotiation, student's achievement can be enhanced. The results also started to shed some light on sustainability of the SWH approach within the school district.

Flow and form in rehabilitation of large-river ecosystems: an example from the Lower Missouri River

USGS Publications Warehouse

Jacobson, R.B.; Galat, D.L.

2006-01-01

On large, intensively engineered rivers like the Lower Missouri, the template of the physical habitat is determined by the nearly independent interaction of channel form and flow regime. We evaluated the interaction between flow and form by modeling four combinations of modern and historical channel form and modern and historical flow regimes. The analysis used shallow, slow water (shallow-water habitat, SWH, defined as depths between 0 and 1.5 m, and current velocities between 0 and 0.75 m/s) as an indicator of habitat that has been lost on many intensively engineered rivers and one that is thought to be especially important in rearing of young fishes. Two-dimensional hydrodynamic models for modern and historical channels of the Lower Missouri River at Hermann, Missouri, indicate substantial differences between the two channels in total availability and spatial characteristics of SWH. In the modern channel, SWH is maximized at extremely low flows and in overbank flows, whereas the historical channel had substantially more SWH at all discharges and SWH increased with increasing discharge. The historical channel form produced 3-7 times the SWH area of the modern channel regardless of flow regime. The effect of flow regime is evident in increased within-year SWH variability with the natural flow regime, including significant seasonal peaks of SWH associated with spring flooding. Comparison with other reaches along the Lower Missouri River indicates that a) channel form is the dominant control of the availability of habitat even in reaches where the hydrograph is more intensively altered, and b) rehabilitation projects that move toward the historical condition can be successful in increasing topographic diversity and thereby decreasing sensitivity of the availability of habitat to flow regime. The relative efficacy of managing flow and form in creating SWH is useful information toward achieving socially acceptable rehabilitation of the ecosystem in large river systems.

Impact of Guided-Inquiry-Based Instruction with a Writing and Reflection Emphasis on Chemistry Students' Critical Thinking Abilities

ERIC Educational Resources Information Center

Gupta, Tanya; Burke, K. A.; Mehta, Akash; Greenbowe, Thomas J.

2015-01-01

The Science Writing Heuristic (SWH) laboratory instruction approach has been used successfully over a decade to engage students in laboratory activities. SWH-based instruction emphasizes knowledge construction through individual writing and reflection, and collaborative learning as a group. In the SWH approach, writing is a core component of…

Effects of the Science Writing Heuristic Approach on the Quality of Prospective Science Teachers' Argumentative Writing and Their Understanding of Scientific Argumentation

ERIC Educational Resources Information Center

Yaman, Fatma

2018-01-01

This study investigates the effect of the science writing heuristic (SWH) approach on the quality of prospective science teachers' (PSTs) argumentative writing and their understanding of the components of argumentation in the SWH approach and their own learning. Ten SWH approach activities were implemented during the semester. The study was…

Serological evidence of pig-to-human influenza virus transmission on Thai swine farms.

PubMed

Kitikoon, Pravina; Sreta, Donruethai; Tuanudom, Ranida; Amonsin, Alongkorn; Suradhat, Sanipa; Oraveerakul, Kanisak; Poovorawan, Yong; Thanawongnuwech, Roongroje

2011-03-24

We investigated influenza interspecies transmission in two commercial swine farms in Thailand. Sera from swine-exposed workers (n=78), age-matched non-swine-exposed healthy people (n=60) and swine populations in both farms (n=85) were studied. Hemagglutination-inhibition (HI) assay was performed on Thai swine H1 viruses (swH1N1 and swH1N2) isolated from both farms. Thai human H1N1 (huH1N1) and pandemic H1N1 2009 (pH1N1) were also used as test antigens. The hemagglutinin (HA) 1 genes of swH1N1 and swH1N2 viruses were sequenced and shown to be genetically distinct from the Thai huH1N1 and pH1N1 viruses. Evidence of pig-to-human influenza virus transmission was found in farm workers with increased odds of elevated antibody titers to both swH1N1 (OR 42.63, 95% CI, 14.65-124) and swH1N2 (OR 58, 95% CI, 13.12-256.3) viruses. No evidence of human-to-pig influenza virus transmission was detected in this study. Copyright © 2010 Elsevier B.V. All rights reserved.

Scottish Women's Hospitals--the 90th anniversary of their work in Serbia.

PubMed

Mikić, Zelimir

2005-01-01

The Scottish Women's Hospitals (SWH), a unique health institution in the history of medicine, staffed entirely by women, was founded soon after the outbreak of the First World War, August 12, 1914 in Edinburgh, by the National Union of Women's Suffrage Societies. The founder and the main driving force behind this organisation was Dr. Elsie Inglis (1864-1917). Although her proposition to the British War Office had been rejected, she offered her services to the Allies (France, Belgium, Russia and Serbia). The first 200 bed SWH unit was sent to France in November 1914, and soon after followed other units, so at the end there were 13 very well equipped SWH units working in the various theatres of war in Belgium, Serbia, Russia, Rumania and Greece. The first unit of SWH came to Serbia in early January 1915, and was located at Kragujevac. Soon after, three other SWH units arrived to Serbia and were stationed at Mladenovac, Valjevo and Lazarevac. It was an enormous help to Serbia, full of wounded and sick people, due to the dreadful typhus epidemic which was devastating the country. A large SWH unit, attached to the Southern Slav Volunteer Division, had worked on the Dobrudja front, and there were three hospitals and a special transport unit on the Salonika Front, which were all engaged in the treatment of Serbian wounded soldiers until the end of the First World War. Two other SWH units, located in France, were treating the Serbian refugees. Serving bravely and honorably on the various theatres of war, the legendary Scottish Women's Hospitals made enormous contributions to the allied war efforts, and helped Serbian people a great deal.

Accurate numerical forward model for optimal retracking of SIRAL2 SAR echoes over open ocean

NASA Astrophysics Data System (ADS)

Phalippou, L.; Demeestere, F.

2011-12-01

The SAR mode of SIRAL-2 on board Cryosat-2 has been designed to measure primarily sea-ice and continental ice (Wingham et al. 2005). In 2005, K. Raney (KR, 2005) pointed out the improvements brought by SAR altimeter for open ocean. KR results were mostly based on 'rule of thumb' considerations on speckle noise reduction due to the higher PRF and to speckle decorrelation after SAR processing. In 2007, Phalippou and Enjolras (PE,2007) provided the theoretical background for optimal retracking of SAR echoes over ocean with a focus on the forward modelling of the power-waveforms. The accuracies of geophysical parameters (range, significant wave heights, and backscattering coefficient) retrieved from SAR altimeter data were derived accounting for SAR echo shape and speckle noise accurate modelling. The step forward to optimal retracking using numerical forward model (NFM) was also pointed out. NFM of the power waveform avoids analytical approximation, a warranty to minimise the geophysical dependent biases in the retrieval. NFM have been used for many years, in operational meteorology in particular, for retrieving temperature and humidity profiles from IR and microwave radiometers as the radiative transfer function is complex (Eyre, 1989). So far this technique was not used in the field of ocean conventional altimetry as analytical models (e.g. Brown's model for instance) were found to give sufficient accuracy. However, although NFM seems desirable even for conventional nadir altimetry, it becomes inevitable if one wish to process SAR altimeter data as the transfer function is too complex to be approximated by a simple analytical function. This was clearly demonstrated in PE 2007. The paper describes the background to SAR data retracking over open ocean. Since PE 2007 improvements have been brought to the forward model and it is shown that the altimeter on-ground and in flight characterisation (e.g antenna pattern range impulse response, azimuth impulse response, altimeter transfer function) can be accurately accounted for, in order to minimise the systematic errors in the retrieval. The paper presents the retrieval of range and SWH for several Cryosat 2 orbits arcs, spanning different sea state conditions. The retrieval results are found to be in excellent agreement with the noise expectations derived from the Cramer-Rao bounds (see PE 2007.). The improvement upon conventional Low Resolution mode is about a factor of two in range. Improvements in SWH accuracy is also discussed. Comparisons with the MSL and conventional LRM-like retracking is also shown. Finally, the paper will give some insights for future oceanic altimetry missions. References : Wingham et al., 2005 : CryoSat: A mission to determine the fluctuations in Earth's land and marine ice fields. Advances in Space Research 37 (2006) 841-871 Raney, R.K. 2005 : Resolution and precision ofa delayDoppler Radar Altimeter, Proc IEEE OCEANS 2005. Phalippou L, V. Enjolras 2007 : Re-tracking of SAR altimeter ocean power waveforms and related accuracies of Sea surface Height, significant wave height and wind speed. Proc IEEE IGARSS 2007. Eyre, J. 1989 : Inversion of cloudy satellite radiances by non linear estimation : Theory and simulation for TOVS. Quaterly Journal of the Royal Meteorological Society, 115, pp1001-1026.

The effect of restructuring student writing in the general chemistry laboratory on student understanding of chemistry and on students' approach to the laboratory course

NASA Astrophysics Data System (ADS)

Rudd, James Andrew, II

Many students encounter difficulties engaging with laboratory-based instruction, and reviews of research have indicated that the value of such instruction is not clearly evident. Traditional forms of writing associated with laboratory activities are commonly in a style used by professional scientists to communicate developed explanations. Students probably lack the interpretative skills of a professional, and writing in this style may not support students in learning how to develop scientific explanations. The Science Writing Heuristic (SWH) is an inquiry-based approach to laboratory instruction designed in part to promote student ability in developing such explanations. However, there is not a convincing body of evidence for the superiority of inquiry-based laboratory instruction in chemistry. In a series of studies, the performance of students using the SWH student template in place of the standard laboratory report format was compared to the performance of students using the standard format. The standard reports had Title, Purpose, Procedure, Data & Observations, Calculations & Graphs, and Discussion sections. The SWH reports had Beginning Questions & Ideas, Tests & Procedures, Observations, Claims, Evidence, and Reflection sections. The pilot study produced evidence that using the SWH improved the quality of laboratory reports, improved student performance on a laboratory exam, and improved student approach to laboratory work. A main study found that SWH students statistically exhibited a better understanding of physical equilibrium when written explanations and equations were analyzed on a lecture exam and performed descriptively better on a physical equilibrium practical exam task. In another main study, the activities covering the general equilibrium concept were restructured as an additional change, and it was found that SWH students exhibited a better understanding of chemical equilibrium as shown by statistically greater success in overcoming the common confusion of interpreting equilibrium as equal concentrations and by statistically better performance when explaining aspects of chemical equilibrium. Both main studies found that students and instructors spent less time on the SWH reports and that students preferred the SWH approach because it increased their level of mental engagement. The studies supported the conclusion that inquiry-based laboratory instruction benefits student learning and attitudes.

Co-infection of classic swine H1N1 influenza virus in pigs persistently infected with porcine rubulavirus.

PubMed

Rivera-Benitez, José Francisco; De la Luz-Armendáriz, Jazmín; Saavedra-Montañez, Manuel; Jasso-Escutia, Miguel Ángel; Sánchez-Betancourt, Ivan; Pérez-Torres, Armando; Reyes-Leyva, Julio; Hernández, Jesús; Martínez-Lara, Atalo; Ramírez-Mendoza, Humberto

2016-02-29

Porcine rubulavirus (PorPV) and swine influenza virus infection causes respiratory disease in pigs. PorPV persistent infection could facilitate the establishment of secondary infections. The aim of this study was to analyse the pathogenicity of classic swine H1N1 influenza virus (swH1N1) in growing pigs persistently infected with porcine rubulavirus. Conventional six-week-old pigs were intranasally inoculated with PorPV, swH1N1, or PorPV/swH1N1. A mock-infected group was included. The co-infection with swH1N1 was at 44 days post-infection (DPI), right after clinical signs of PorPV infection had stopped. The pigs of the co-infection group presented an increase of clinical signs compared to the simple infection groups. In all infected groups, the most recurrent lung lesion was hyperplasia of the bronchiolar-associated lymphoid tissue and interstitial pneumonia. By means of immunohistochemical evaluation it was possible to demonstrate the presence of the two viral agents infecting simultaneously the bronchiolar epithelium. Viral excretion of PorPV in nasal and oral fluid was recorded at 28 and 52 DPI, respectively. PorPV persisted in several samples from respiratory tissues (RT), secondary lymphoid organs (SLO), and bronchoalveolar lavage fluid (BALF). For swH1N1, the viral excretion in nasal fluids was significantly higher in single-infected swH1N1 pigs than in the co-infected group. However, the co-infection group exhibited an increase in the presence of swH1N1 in RT, SLO, and BALF at two days after co-infection. In conclusion, the results obtained confirm an increase in the clinical signs of infection, and PorPV was observed to impact the spread of swH1N1 in analysed tissues in the early stage of co-infection, although viral shedding was not enhanced. In the present study, the interaction of swH1N1 infection is demonstrated in pigs persistently infected with PorPV. Copyright © 2016 Elsevier B.V. All rights reserved.

Retrospective swine influenza serological surveillance in the four highest pig density provinces of Thailand before the introduction of the 2009 pandemic Influenza A virus subtype H1N1 using various antibody detection assays.

PubMed

Sreta, Donruethai; Jittimanee, Suphattra; Charoenvisal, Nataya; Amonsin, Alongkorn; Kitikoon, Pravina; Thanawongnuwech, Roongroje

2013-01-01

Genetic characterization of the hemagglutinin gene of the 6 selected Thai Swine influenza virus (SIV) isolates (4 H1 and 2 H3 isolates) used in the establishment of a hemagglutination inhibition (HI) assay was analyzed. Based on the phylogenetic analysis, Thai SIVs could be divided into 3 clusters of the H1 viruses (clusters I and II belonging to classical swine H1α, and cluster III belonging to classical swine H1γ), and 2 clusters of the H3 viruses both belonging to human-like 1970s. The serological results indicated that swH1N1-06 (H1 cluster I) is a suitable representative SIV for the HI test antigen to detect H1 SIV-specific antibodies in the Thai swine population, while both swH3N2-05 and swH3N2-07 should be used for Thai H3 SIV-specific antibody detection. The HI test results of swine sera collected from pigs in the 4 highest pig population provinces of Thailand indicated that the percentage of pigs seropositive to swH3N2-07 was highest compared to swH1N1-06, swH1N1-09, and swH3N2-05 (85.4%, 50.1%, 18.6%, and 15.8%, respectively). It should be noted that countries lacking SIV genetic information should be concerned with determining the most suitable HI test antigens to use when performing the tests due to the genetic variation and limited cross-reaction of SIVs. The results of the current study demonstrated that HI tests should be implemented with the suitable field strains as the representative test antigen to ascertain accurate SIV serostatus in Thailand and that test antigens should be genetically analyzed and compared with circulating strains regularly.

Using the science writing heuristic approach as a tool for assessing and promoting students' conceptual understanding and perceptions in the general chemistry laboratory

NASA Astrophysics Data System (ADS)

Mohammad, Elham Ghazi

This thesis reports on a study that examined the impact of implementing SWH (inquiry-based approach) in a general chemistry lab on non-science-major students' understanding of chemistry concepts and students' perceptions toward writing in science and implementing SWH. This study was conducted in a large university in the Midwest of the United States in a college freshman chemistry laboratory for non-science-major students. The research framework is presented including the following: the qualitative research design with the observation as data collection method for this design and the criteria for teacher level of implementation and the ranking mechanism; and the quantitative research design with data collection and analysis methods including pre- and post-conceptual exams, lecture question, open-ended surveys. This research was based on a quasi-experimental mixed-method design a focus on student performance on higher order conceptual questions, and open-ended survey at the end of semester about their perception toward writing to learn ad implementing SWH. Results from the qualitative and quantitative component indicated that implementing SWH approach has notably enhanced both male and female conceptual understanding and perception toward chemistry and implementing SWH. It is known that there is gender gap in science, where female have lower perception and self confident toward science. Interestingly, my findings have showed that implementing SWH helped closing the gap between male and female who started the semester with a statistically significant lower level of conceptual understanding of chemistry concepts among females than males.

Evaluation of stormwater harvesting sites using multi criteria decision methodology

NASA Astrophysics Data System (ADS)

Inamdar, P. M.; Sharma, A. K.; Cook, Stephen; Perera, B. J. C.

2018-07-01

Selection of suitable urban stormwater harvesting sites and associated project planning are often complex due to spatial, temporal, economic, environmental and social factors, and related various other variables. This paper is aimed at developing a comprehensive methodology framework for evaluating of stormwater harvesting sites in urban areas using Multi Criteria Decision Analysis (MCDA). At the first phase, framework selects potential stormwater harvesting (SWH) sites using spatial characteristics in a GIS environment. In second phase, MCDA methodology is used for evaluating and ranking of SWH sites in multi-objective and multi-stakeholder environment. The paper briefly describes first phase of framework and focuses chiefly on the second phase of framework. The application of the methodology is also demonstrated over a case study comprising of the local government area, City of Melbourne (CoM), Australia for the benefit of wider water professionals engaged in this area. Nine performance measures (PMs) were identified to characterise the objectives and system performance related to the eight alternative SWH sites for the demonstration of the application of developed methodology. To reflect the stakeholder interests in the current study, four stakeholder participant groups were identified, namely, water authorities (WA), academics (AC), consultants (CS), and councils (CL). The decision analysis methodology broadly consisted of deriving PROMETHEE II rankings of eight alternative SWH sites in the CoM case study, under two distinct group decision making scenarios. The major innovation of this work is the development and application of comprehensive methodology framework that assists in the selection of potential sites for SWH, and facilitates the ranking in multi-objective and multi-stakeholder environment. It is expected that the proposed methodology will assist the water professionals and managers with better knowledge that will reduce the subjectivity in the selection and evaluation of SWH sites.

Enhancing science literacy through implementation of writing-to-learn strategies: Exploratory studies in high school biology

NASA Astrophysics Data System (ADS)

Hohenshell, Liesl Marie

Some evidence of benefits from writing-to-learn techniques exists; however, more research is needed describing the instructional context used to support learning through writing and the quality of learning that results from particular tasks. This dissertation includes three papers, building on past research linking inquiry, social negotiation, and writing strategies to enhance scientific literacy skills of high school biology students. The interactive constructivist position informed the pedagogical approach for two empirical, classroom-based studies utilizing mixed methods to identify quantitative differences in learning outcomes and students' perceptions of writing tasks. The first paper reports students with planned writing activities communicated biotechnology content better in textbook explanations to a younger audience, but did not score better on tests than students who had delayed planning experiences. Students with two writing experiences as opposed to one, completing a newspaper article, scored better on conceptual questions both after writing and on a test 8 weeks later. The difference in treatments initially impacted males compared to females, but this effect disappeared with subsequent writing. The second paper reports two parallel studies of students completing two different writing types, laboratory and summary reports. Three comparison groups were used, Control students wrote in a traditional format, while SWH group students used the Science Writing Heuristic (SWH) during guided inquiry laboratories. Control students wrote summary reports to the teacher, while SWH students wrote either to the teacher or to peers (Peer Review group). On conceptual questions, findings indicated that after laboratory writing SWH females performed better compared to SWH males and Control females; and as a group SWH students performed better than Control students on a test following summary reports (Study 1). These results were not replicated in Study 2. An open-ended survey revealed findings that persisted in both studies; compared to Control students, SWH students were more likely to describe learning as they were writing and to report distinct thinking was required in completing the two writing types. Students' comments across studies provide support for using non-traditional writing tasks as a means to assist learning. Various implications for writing to serve learning are reported, including identification of key support conditions.

Using the Science Writing Heuristic to Improve Undergraduate Writing in Biology

ERIC Educational Resources Information Center

Cronje, Ruth; Murray, Kelly; Rohlinger, Spencer; Wellnitz, Todd

2013-01-01

Our objective was to investigate the impact of the Science Writing Heuristic (SWH) on undergraduates' ability to express logical conclusions and include appropriate evidence in formal writing assignments. Students in three laboratory sections were randomly allocated to the SWH treatment ("n"?=?51 students) with another three sections…

Adaptive re-tracking algorithm for retrieval of water level variations and wave heights from satellite altimetry data for middle-sized inland water bodies

NASA Astrophysics Data System (ADS)

Troitskaya, Yuliya; Lebedev, Sergey; Soustova, Irina; Rybushkina, Galina; Papko, Vladislav; Baidakov, Georgy; Panyutin, Andrey

One of the recent applications of satellite altimetry originally designed for measurements of the sea level [1] is associated with remote investigation of the water level of inland waters: lakes, rivers, reservoirs [2-7]. The altimetry data re-tracking algorithms developed for open ocean conditions (e.g. Ocean-1,2) [1] often cannot be used in these cases, since the radar return is significantly contaminated by reflection from the land. The problem of minimization of errors in the water level retrieval for inland waters from altimetry measurements can be resolved by re-tracking satellite altimetry data. Recently, special re-tracking algorithms have been actively developed for re-processing altimetry data in the coastal zone when reflection from land strongly affects echo shapes: threshold re-tracking, The other methods of re-tracking (threshold re-tracking, beta-re-tracking, improved threshold re-tracking) were developed in [9-11]. The latest development in this field is PISTACH product [12], in which retracking bases on the classification of typical forms of telemetric waveforms in the coastal zones and inland water bodies. In this paper a novel method of regional adaptive re-tracking based on constructing a theoretical model describing the formation of telemetric waveforms by reflection from the piecewise constant model surface corresponding to the geography of the region is considered. It was proposed in [13, 14], where the algorithm for assessing water level in inland water bodies and in the coastal zone of the ocean with an error of about 10-15 cm was constructed. The algorithm includes four consecutive steps: - constructing a local piecewise model of a reflecting surface in the neighbourhood of the reservoir; - solving a direct problem by calculating the reflected waveforms within the framework of the model; - imposing restrictions and validity criteria for the algorithm based on waveform modelling; - solving the inverse problem by retrieving a tracking point by the improved threshold algorithm. The possibility of determination of significant wave height (SWH) in the lakes through a two-step adaptive retracking is also studied. Calculation of the parameter SWH for Gorky Reservoir from May 2010 to March 2014 showed the anomalously high values of SWH, derived from altimetry data [15], which means that the calibration of this SWH for inland waters is required. Calibration ground measurements were performed at Gorky reservoir in 2011-2013, when wave height, wind speed and air temperature were collected by equipment placed on a buoy [15] collocated with Jason-1 and Jason-2 altimetry data acquisition. The results obtained on the basis of standard algorithm and method for adaptive re-tracking at Rybinsk , Gorky , Kuibyshev , Saratov and Volgograd reservoirs and middle-sized lakes of Russia: Chany, Segozero, Hanko, Oneko, Beloye, water areas of which are intersected by the Jason-1,2 tracks, were compared and their correlation with the observed data of hydrological stations in reservoirs and lakes was investigated. It was noted that the Volgograd reservoir regional re-tracking to determine the water level , while the standard GDR data are practically absent. REFERENCES [1] AVISO/Altimetry. User Handbook. Merged TOPEX/ POSEIDON Products. Edition 3.0. AVISO. Toulouse., 1996. [2] C.M. Birkett et al., “Surface water dynamics in the Amazon Basin: Application of satellite radar altimetry,” J. Geophys. Res., vol. 107, pp. 8059, 2002. [3] G. Brown, “The average impulse response of a rough surface and its applications,” IEEE Trans. Antennas Propagat., vol. 25, pp. 67-74, 1977. [4] I.O. Campos et al., “Temporal variations of river basin waters from Topex/Poseidon satellite altimetry. Application to the Amazon basin,” Earth and Planetary Sciences, vol. 333, pp. 633-643, 2001. [5] A.V. Kouraev et al., “Ob’ river discharge from TOPEX/Poseidon satellite altimetry (1992-2002),” Rem. Sens. Environ., vol. 93, pp. 238-245, 2004. [6] S.A. Lebedev, and A.G. Kostianoy, Satellite Altimetry of the Caspian Sea. Moscow : MORE, [in Russian], 2005. [7] P. A. M. Berry et al., “Global inland water monitoring from multi-mission altimetry”, Geophys. Res. Lett., vol. 32, pp. L16401, 2005. [8] S. Calmant, and F. Seyler, “Continental surface waters from satellite altimetry,” Geosciences C.R., vol. 338, pp. 1113-1122, 2006. [9] C. H. Davis, “A robust threshold retracking algorithm for measuring ice sheet surface elevation change from satellite radar altimeters,” IEEE Trans. Geosci. Remote Sens., vol. 35, pp. 974-979, 1997. [10] X. Deng, and W. E. Featherstone, “A coastal retracking system for satellite radar altimeter waveforms: Application to ERS-2 around Australia,” J. Geophys. Res., vol. 111, pp. C06012, 2006. [11] J. Guo et al., “Lake level variations monitored with satellite altimetry waveform retracking,” IEEE J. Sel. Topics Appl. Earth Obs., vol. 2(2), pp. 80-86, 2009. [12] Mercier F., Rosmorduc V., Carrere L., Thibaut P., Coastal and Hydrology Altimetry product (PISTACH) handbook. Version 1.0. 2010. [13] Yu.Troitskaya et al., “Satellite altimetry of inland water bodies,” Water Resources, vol. 39(2), pp.184-199, 2012. [14] Yu.Troitskaya et al., “Adaptive retracking of Jason-1 altimetry data for inland waters: the example of the Gorky Reservoir”, Int. J. Rem. Sens., vol. 33, pp. 7559-7578, 2012. [15] Yu.Troitskaya et al., , "Adaptive retracking of Jason-1,2 satellite altimetry data for the Volga river reservoirs ," IEEE J. Sel. Topics Appl. Earth Obs., issue 99, 2013, doi: 10.1109/JSTARS.2013.2267092.

Balancing Self-Directed Learning with Expert Mentoring: The Science Writing Heuristic Approach

ERIC Educational Resources Information Center

Shelley, Mack; Fostvedt, Luke; Gonwa-Reeves, Christopher; Baenziger, Joan; McGill, Michael; Seefeld, Ashley; Hand, Brian; Therrien, William; Taylor, Jonte; Villanueva, Mary Grace

2012-01-01

This study focuses on the implementation of the Science Writing Heuristic (SWH) curriculum (Hand, 2007), which combines current understandings of learning as a cognitive and negotiated process with the techniques of argument-based inquiry, critical thinking skills, and writing to strengthen student outcomes. Success of SWH is dependent on the…

Using the Science Writing Heuristic to Improve Students' Understanding of General Equilibrium

ERIC Educational Resources Information Center

Rudd, James A., II; Greenbowe, Thomas J.; Hand, Brian M.

2007-01-01

This study compared the performance of students using the Science Writing Heuristic (SWH) approach and students using a standard or traditional laboratory curriculum on lecture exams and a laboratory practical exam on a specific topic, chemical equilibrium. The SWH helps students do inquiry science laboratory work by structuring the laboratory…

Extending Students' Practice of Metacognitive Regulation Skills with the Science Writing Heuristic

NASA Astrophysics Data System (ADS)

van Opstal, Mary T.; Daubenmire, Patrick L.

2015-05-01

Metacognition can be described as an internal conversation that seeks to answer the questions, 'how much do I really know about what I am learning' and, 'how am I monitoring what I am learning?' Metacognitive regulation skills are critical to meaningful learning because they facilitate the abilities to recognize the times when one's current level of understanding is insufficient and to identify the needs for closing the gap in understanding. This research explored how using the Science Writing Heuristic (SWH) as an instructional approach in a laboratory classroom affected students' practice of metacognitive skills while solving open-ended laboratory problems. Within our qualitative research design, results demonstrate that students in the SWH environment, compared to non-SWH students, used metacognitive strategies to a different degree and to a different depth when solving open-ended laboratory problems. As students engaged in higher levels of metacognitive regulation, peer collaboration became a prominent path for supporting the use of metacognitive strategies. Students claimed that the structure of the SWH weekly laboratory experiments improved their ability to solve open-ended lab problems. Results from this study suggest that using instruction that encourages practice of metacognitive strategies can improve students' use of these strategies.

Examining the Value of a Scaffolded Critique Framework to Promote Argumentative and Explanatory Writings Within an Argument-Based Inquiry Approach

NASA Astrophysics Data System (ADS)

Jang, Jeong-yoon; Hand, Brian

2017-12-01

This study investigated the value of using a scaffolded critique framework to promote two different types of writing—argumentative writing and explanatory writing—with different purposes within an argument-based inquiry approach known as the Science Writing Heuristic (SWH) approach. A quasi-experimental design with sixth and seventh grade students taught by two teachers was used. A total of 170 students participated in the study, with 87 in the control group (four classes) and 83 in the treatment group (four classes). All students used the SWH templates as an argumentative writing to guide their written work and completed these templates during the SWH investigations of each unit. After completing the SWH investigations, both groups of students were asked to complete the summary writing task as an explanatory writing at the end of each unit. All students' writing samples were scored using analytical frameworks developed for the study. The results indicated that the treatment group performed significantly better on the explanatory writing task than the control group. In addition, the results of the partial correlation suggested that there is a very strong significantly positive relationship between the argumentative writing and the explanatory writing.

Effects of an SWH Approach and Self-Evaluation on Sixth Grade Students' Learning and Retention of an Electricity Unit

ERIC Educational Resources Information Center

Memis, Esra Kabatas; Seven, Sabriye

2015-01-01

The purpose of this study is to explore the effects of guided, inquiry-based laboratory activities using the Science Writing Heuristic (SWH) approach and self-evaluation on students' science achievement. The study involved three sixth grade classes studying an electricity unit taught by the same primary school teacher. Before the study began, one…

Multilevel Models for Estimating the Effect of Implementing Argumentation-Based Elementary Science Instruction

ERIC Educational Resources Information Center

Shelley, Mack; Gonwa-Reeves, Christopher; Baenziger, Joan; Seefeld, Ashley; Hand, Brian; Therrien, William; Villanueva, Mary Grace; Taylor, Jonte

2012-01-01

The purpose of this paper is to examine the impact of implementation of the Science Writing Heuristic (SWH) approach at 5th grade level in the public school system in Iowa as measured by Cornell Critical Thinking student test scores. This is part of a project that overall tests the efficacy of the SWH inquiry-based approach to build students'…

High School Students' Attitudes and Beliefs on Using the Science Writing Heuristic in an Advanced Placement Chemistry Class

ERIC Educational Resources Information Center

Putti, Alice

2011-01-01

This paper discusses student attitudes and beliefs on using the Science Writing Heuristic (SWH) in an advanced placement (AP) chemistry classroom. During the 2007 school year, the SWH was used in a class of 24 AP chemistry students. Using a Likert-type survey, student attitudes and beliefs on the process were determined. Methods for the study are…

Life cycle environmental impacts of domestic solar water heaters in Turkey: The effect of different climatic regions.

PubMed

Uctug, Fehmi Gorkem; Azapagic, Adisa

2018-05-01

Solar water heating (SWH) systems could help reduce environmental impacts from energy use but their performance and impacts depend on the climate. This paper considers how these vary for residential SWH across four different climatic regions in Turkey, ranging from hot to cold climates. Life cycle assessment was used for these purposes. The results suggest that in the hotter regions, the impacts of SWH are 1.5-2 times lower than those of natural gas boilers. A similar trend was observed in the two colder regions except for acidification, which was four times higher than that of the boiler. The raw materials and electricity required for the manufacturing of the systems were found to be the most important contributors to the impacts. Recycling the major components instead of landfilling reduced human toxicity potential by 50% but had only a small effect (5%) on the other impacts. The impacts were highly sensitive to the type of material used for the construction of the hot storage tank, but were not affected by transport and end-of life recycling. The only exception to the latter is human toxicity potential which decreased significantly with greater recycling. Extrapolating the results at the national level showed that SWH systems could reduce the annual greenhouse gas emissions in Turkey by 790kt CO 2 -eq. and would save the economy $162.5millionperyear through the avoided imports of natural gas. All other impacts would also be reduced significantly (3-32 times), except for acidification which would double. Therefore, SWH systems should be deployed more extensively in Turkey but government incentives may be needed to stimulate the uptake. Copyright © 2017 Elsevier B.V. All rights reserved.

Innovative Seismic Array Analysis for Studies of Wave Propagation in the Earth

DTIC Science & Technology

1999-04-30

station signal power can be written as 0.5 - 3.5 Hz. 2.0 -14.0 Hz. Pmg(f,t,u) = \\d\\ 2-tr[C(f,t,u)], (6) where tr is the trace of...the matrix and d is an A^ X 1 vector N of station weights such that 2 d„ = 1. We will be using uniform weighting such that d„ = \\IN. The power of... stations SEH, SWH, and NH. Wpw 2 ukm{ uk , Uj) X m( uk , Uj) ( uk , Uj) &4 (9) where m( uk , Uj) 0 S(f, t, uk , M,.) < 0.9Speak (/, t)f S(f,

Lethal thermal maxima for age-0 pallid and shovelnose sturgeon: Implications for shallow water habitat restoration

USGS Publications Warehouse

Deslauriers, David; Heironimus, Laura B.; Chipps, Steven R.

2016-01-01

We evaluated temperature tolerance in age-0 pallid and shovelnose sturgeon (Scaphirhynchus albus and Scaphirhynchus platorynchus), two species that occur sympatrically in the Missouri and Mississippi Rivers. Fish (0.04–18 g) were acclimated to water temperatures of 13, 18 or 24 °C to quantify temperatures associated with lethal thermal maxima (LTM). The results show that no difference in thermal tolerance existed between the two sturgeon species, but that LTM was significantly related to body mass and acclimation temperature. Multiple linear regression analysis was used to estimate LTM, and outputs from the model were compared with water temperatures measured in the shallow water habitat (SWH) of the Missouri River. Observed SWH temperatures were not found to yield LTM conditions. The model developed here is to serve as a general guideline in the development of future SWH.

Examining Arguments Generated by Year 5, 7, and 10 Students in Science Classrooms

NASA Astrophysics Data System (ADS)

Choi, Aeran; Notebaert, Andrew; Diaz, Juan; Hand, Brian

2010-03-01

A critical component of science is the role of inquiry and argument in moving scientific knowledge forward. However, while students are expected to engage in inquiry activities in science classrooms, there is not always a similar emphasis on the role of argument within the inquiry activities. Building from previous studies on the Science Writing Heuristic (SWH), we were keen to find out if the writing structure used in the SWH approach helped students in Year 5, 7, and 10 to create well constructed arguments. We were also interested in examining which argument components were important for the quality of arguments generated by these students. Two hundred and ninety six writing samples were scored using an analysis framework to evaluate the quality of arguments. Step-wise multiple regression analyses were conducted to determine important argument components. The results of this study suggest that the SWH approach is useful in assisting students to develop reasonable arguments. The critical element determining the quality of the arguments is the relationship between the student’s written claims and his or her evidence.

Capsular Sialic Acid of Streptococcus suis Serotype 2 Binds to Swine Influenza Virus and Enhances Bacterial Interactions with Virus-Infected Tracheal Epithelial Cells

PubMed Central

Wang, Yingchao; Gagnon, Carl A.; Savard, Christian; Music, Nedzad; Srednik, Mariela; Segura, Mariela; Lachance, Claude; Bellehumeur, Christian

2013-01-01

Streptococcus suis serotype 2 is an important swine bacterial pathogen, and it is also an emerging zoonotic agent. It is unknown how S. suis virulent strains, which are usually found in low quantities in pig tonsils, manage to cross the first host defense lines to initiate systemic disease. Influenza virus produces a contagious infection in pigs which is frequently complicated by bacterial coinfections, leading to significant economic impacts. In this study, the effect of a preceding swine influenza H1N1 virus (swH1N1) infection of swine tracheal epithelial cells (NTPr) on the ability of S. suis serotype 2 to adhere to, invade, and activate these cells was evaluated. Cells preinfected with swH1N1 showed bacterial adhesion and invasion levels that were increased more than 100-fold compared to those of normal cells. Inhibition studies confirmed that the capsular sialic acid moiety is responsible for the binding to virus-infected cell surfaces. Also, preincubation of S. suis with swH1N1 significantly increased bacterial adhesion to/invasion of epithelial cells, suggesting that S. suis also uses swH1N1 as a vehicle to invade epithelial cells when the two infections occur simultaneously. Influenza virus infection may facilitate the transient passage of S. suis at the respiratory tract to reach the bloodstream and cause bacteremia and septicemia. S. suis may also increase the local inflammation at the respiratory tract during influenza infection, as suggested by an exacerbated expression of proinflammatory mediators in coinfected cells. These results give new insight into the complex interactions between influenza virus and S. suis in a coinfection model. PMID:24082069

Development of an Ultra-Low-Cost Solar Water Heater: Cooperative Research and Development Final Report, CRADA Number CRD-12-487

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

Merrigan, Tim

2016-02-17

NREL and RhoTech will collaborate to bring long-lived, ultra-low-cost, high-performance solar water heaters (SWH) to market readiness. An existing RhoTech design uses seam-welded polymer thin films to make an unglazed thermosiphon, and this design will be modified to improve durability through ultraviolet and overheat protection, and to improve performance by adding a glazing to the collector. Two generations of the new glazed systems will be tested in the field, resulting in a robust market-ready SWH design that can be installed for under $1,000 without rebates.

Assessment of Shallow-Water Habitat Availability in Modified Dike Structures, Lower Missouri River, 2004

USGS Publications Warehouse

Jacobson, Robert B.; Elliott, Caroline M.; Johnson, Harold E.

2004-01-01

This study documented the effects of wing-dike notching on the availabilit of shallow water habitat in the Lower Missouri River. Five wing dikes were surveyed in late May 2004 after they were notched in early May as part of shallow-water habitat (SWH) rehabilitation activities undertaken by the U.S. Army Corps of Engineers. Surveys included high-resolution hydroacoustic depth, velocity, and substrate mapping. Relations of bottom elevations within the wing dike fields to index discharges and water-surface elevations indicate that little habitat meeting the SWH definition was created immediately following notching. This result is not unexpected, as significant geomorphic adjustment may require large flow events. Depth, velocity, and substrate measurements in the post-rehabilitation time period provide baseline data for monitoring ongoing changes. Differences in elevation and substrate were noted at all sites. Most dike fields showed substantial aggradation and replacement of mud substrate with sandier sediment, although the changes did not result in increased availability of SWH at the index discharge. It is not known how much of the elevation and substrate changes can be attributed directly to notching and how much would result from normal sediment transport variation.

Root bark of Sambucus Williamsii Hance promotes rat femoral fracture healing by the BMP-2/Runx2 signaling pathway.

PubMed

Yang, Bingyou; Lin, Xiaoying; Tan, Jinyan; She, Xian; Liu, Yan; Kuang, Haixue

2016-09-15

Sambucus Williamsii Hance (SWH) is a plant from a family of Caprifoliaceae, which has a long medical history of use as an effective folk treatment for fracture bruises. To evaluate the effects of 50% ethanol extracts of root-bark of Sambucus Williamsii Hance(EE-rbSWH) on fracture healing of rats and explore its mechanism of actions related to the BMP-2 signaling pathway. EE-rbSWH was orally administered at the doses of 340 and 680mg/kg to adult Sprague-Dawley rats with operation of open femur fracture completely for 2, 4 and 8 weeks. And the rats of sham operation and Model groups were administered Vehicle (distilled water 0.8mL/200g/day). Firstly, the bone X-ray morphology and bone mineral density(BMD) of the fracture site were observed and measured after anesthesia the rats at weeks 2, 4, and 8 after surgery, then the serum levels of alkaline phosphatase(ALP) and osteocalcin (BGP) were measured; Secondly, the tissue morphology of the fracture site was observed after sacrificed the rats; Thirdly, the formation of mineralized nodules in bone marrow stromal cells(BMSC) were evaluated at week 2; Lastly, the genes levels of BMP-2 and Runx2 in the femur were detected at week 2 and 4, and the proteins expression of BMP-2 signaling pathway (BMP-2, BMPRIB, BMPRII and Runx2) in the femur also were detected at week 2. EE-rbSWH remarkably accelerated fracture healing by promoting bone formation at all the time points of fracture healing. Mainly by increasing the BMD level at the fracture site, the levels of serum ALP and BGP, and also the numbers increasing of calcified nodules in BMSC. The mechanism studies, EE-rbSWH can promote fracture healing by enhancing the expressions of BMP-2 and Runx2 mRNA, and also the proteins of BMP-2, BMPRIB, BMPRII and Runx2 at the fracture site of rats. Our results suggested that 50% ethanol extracts of root-bark of Sambucus Williamsii Hance can accelerate fracture healing by recruitment of osteoblasts at the fracture site and through up-regulation of the BMP-2 signaling pathway. Copyright © 2016. Published by Elsevier Ireland Ltd.

On the Simulation of Sea States with High Significant Wave Height for the Validation of Parameter Retrieval Algorithms for Future Altimetry Missions

NASA Astrophysics Data System (ADS)

Kuschenerus, Mieke; Cullen, Robert

2016-08-01

To ensure reliability and precision of wave height estimates for future satellite altimetry missions such as Sentinel 6, reliable parameter retrieval algorithms that can extract significant wave heights up to 20 m have to be established. The retrieved parameters, i.e. the retrieval methods need to be validated extensively on a wide range of possible significant wave heights. Although current missions require wave height retrievals up to 20 m, there is little evidence of systematic validation of parameter retrieval methods for sea states with wave heights above 10 m. This paper provides a definition of a set of simulated sea states with significant wave height up to 20 m, that allow simulation of radar altimeter response echoes for extreme sea states in SAR and low resolution mode. The simulated radar responses are used to derive significant wave height estimates, which can be compared with the initial models, allowing precision estimations of the applied parameter retrieval methods. Thus we establish a validation method for significant wave height retrieval for sea states causing high significant wave heights, to allow improved understanding and planning of future satellite altimetry mission validation.

Azimuth cut-off model for significant wave height investigation along coastal water of Kuala Terengganu, Malaysia

NASA Astrophysics Data System (ADS)

Marghany, Maged; Ibrahim, Zelina; Van Genderen, Johan

2002-11-01

The present work is used to operationalize the azimuth cut-off concept in the study of significant wave height. Three ERS-1 images have been used along the coastal waters of Terengganu, Malaysia. The quasi-linear transform was applied to map the SAR wave spectra into real ocean wave spectra. The azimuth cut-off was then used to model the significant wave height. The results show that azimuth cut-off varied with the different period of the ERS-1 images. This is because of the fact that the azimuth cut-off is a function of wind speed and significant wave height. It is of interest to find that the significant wave height modeled from azimuth cut-off is in good relation with ground wave conditions. It can be concluded that ERS-1 can be used as a monitoring tool in detecting the significant wave height variation. The azimuth cut-off can be used to model the significant wave height. This means that the quasi-linear transform could be a good application to significant wave height variation during different seasons.

A climatology of extreme wave height events impacting eastern Lake Ontario shorelines

NASA Astrophysics Data System (ADS)

Grieco, Matthew B.; DeGaetano, Arthur T.

2018-05-01

Model-derived wave height data for points along the eastern Lake Ontario shoreline provide the basis for a 36-year climatology of extreme wave heights. The most extreme wave heights exceed 6 m at all locations, except for those along the extreme northeastern shoreline of the Lake. Typically extreme wave events are a regional phenomenon, affecting multiple locations along the eastern and southeastern shoreline. A pronounced seasonal cycle in wave event occurrence is characterized by peaks in autumn and spring, with an absence of 99.9th percentile wave heights during summer. Less extreme (90th percentile heights) occur in all months with a peak in winter. Extreme wave events are most often associated with a low pressure center tracking to the north of Lake Ontario from the Ohio Valley. This track produces the strong winds > 10 ms-1 and predominantly west-to-east wind fetch that characterize high wave height events. The seasonal frequency of the wave events exceeding the historical 95th percentile has shown a statistically significant increase at most locations since 1979. This has been partially offset by declines in the frequency of events with wave heights between the 90 and 95th percentile. Seasonal extreme wave height frequency is also found to be related to the occurrence of El Niño. During El Niño winters, there are significantly fewer events with wave heights exceeding 2.5 m than would be expected by chance. A corresponding relationship to La Niña occurrence is not evident.

A Global Sensitivity Analysis Method on Maximum Tsunami Wave Heights to Potential Seismic Source Parameters

NASA Astrophysics Data System (ADS)

Ren, Luchuan

2015-04-01

A Global Sensitivity Analysis Method on Maximum Tsunami Wave Heights to Potential Seismic Source Parameters Luchuan Ren, Jianwei Tian, Mingli Hong Institute of Disaster Prevention, Sanhe, Heibei Province, 065201, P.R. China It is obvious that the uncertainties of the maximum tsunami wave heights in offshore area are partly from uncertainties of the potential seismic tsunami source parameters. A global sensitivity analysis method on the maximum tsunami wave heights to the potential seismic source parameters is put forward in this paper. The tsunami wave heights are calculated by COMCOT ( the Cornell Multi-grid Coupled Tsunami Model), on the assumption that an earthquake with magnitude MW8.0 occurred at the northern fault segment along the Manila Trench and triggered a tsunami in the South China Sea. We select the simulated results of maximum tsunami wave heights at specific sites in offshore area to verify the validity of the method proposed in this paper. For ranking importance order of the uncertainties of potential seismic source parameters (the earthquake's magnitude, the focal depth, the strike angle, dip angle and slip angle etc..) in generating uncertainties of the maximum tsunami wave heights, we chose Morris method to analyze the sensitivity of the maximum tsunami wave heights to the aforementioned parameters, and give several qualitative descriptions of nonlinear or linear effects of them on the maximum tsunami wave heights. We quantitatively analyze the sensitivity of the maximum tsunami wave heights to these parameters and the interaction effects among these parameters on the maximum tsunami wave heights by means of the extended FAST method afterward. The results shows that the maximum tsunami wave heights are very sensitive to the earthquake magnitude, followed successively by the epicenter location, the strike angle and dip angle, the interactions effect between the sensitive parameters are very obvious at specific site in offshore area, and there exist differences in importance order in generating uncertainties of the maximum tsunami wave heights for same group parameters at different specific sites in offshore area. These results are helpful to deeply understand the relationship between the tsunami wave heights and the seismic tsunami source parameters. Keywords: Global sensitivity analysis; Tsunami wave height; Potential seismic tsunami source parameter; Morris method; Extended FAST method

Incident wave, infragravity wave, and non-linear low-frequency bore evolution across fringing coral reefs

NASA Astrophysics Data System (ADS)

Storlazzi, C. D.; Griffioen, D.; Cheriton, O. M.

2016-12-01

Coral reefs have been shown to significantly attenuate incident wave energy and thus provide protection for 100s of millions of people globally. To better constrain wave dynamics and wave-driven water levels over fringing coral reefs, a 4-month deployment of wave and tide gauges was conducted across two shore-normal transects on Roi-Namur Island and two transects on Kwajalein Island in the Republic of the Marshall Islands. At all locations, although incident wave (periods <25 s) heights were an order of magnitude greater than infragravity wave (periods > 250 s) heights on the outer reef flat just inshore of the zone of wave breaking, the infragravity wave heights generally equaled the incident wave heights by the middle of the reef flat and exceeded the incident wave heights on the inner reef flat by the shoreline. The infragravity waves generally were asymmetric, positively skewed, bore-like forms with incident-band waves riding the infragravity wave crest at the head of the bore; these wave packets have similar structure to high-frequency internal waves on an internal wave bore. Bore height was shown to scale with water depth, offshore wave height, and offshore wave period. For a given tidal elevation, with increasing offshore wave heights, such bores occurred more frequently on the middle reef flat, whereas they occurred less frequently on the inner reef flat. Skewed, asymmetric waves are known to drive large gradients in velocity and shear stress that can transport material onshore. Thus, a better understanding of these low-frequency, energetic bores on reef flats is critical to forecasting how coral reef-lined coasts may respond to sea-level rise and climate change.

Quantification of nearshore morphology based on video imaging

USGS Publications Warehouse

Alexander, P.S.; Holman, R.A.

2004-01-01

The Argus network is a series of video cameras with aerial views of beaches around the world. Intensity contrasts in time exposure images reveal areas of preferential breaking, which are closely tied to underlying bed morphology. This relationship was further investigated, including the effect of tidal elevation and wave height on the presence of wave breaking and its cross-shore position over sand bars. Computerized methods of objectively extracting shoreline and sand bar locations were developed, allowing the vast quantity of data generated by Argus to be more effectively examined. Once features were identified in the images, daily alongshore mean values were taken to create time series of shoreline and sand bar location, which were analyzed for annual cycles and cross-correlated with wave data to investigate environmental forcing and response. These data extraction techniques were applied to images from four of the Argus camera sites. A relationship between wave height and shoreline location was found in which increased wave heights resulted in more landward shoreline positions; given the short lag times over which this correlation was significant, and that the strong annual signal in wave height was not replicated in the shoreline time series, it is likely that this relationship is a result of set-up during periods of large waves. Wave height was also found to have an effect on sand bar location, whereby an increase in wave height resulted in offshore bar migration. This correlation was significant over much longer time lags than the relationship between wave height and shoreline location, and a strong annual signal was found in the location of almost all observed bars, indicating that the sand bars are migrating with changes in wave height. In the case of the site with multiple sand bars, the offshore bars responded more significantly to changes in wave height, whereas the innermost bar seemed to be shielded from incident wave energy by breaking over the other bars. A relationship was also found between a site's mean wave height and inner sand bar location; sites with the highest wave heights tended to have sand bars farther from shore than those with relatively low wave heights. ?? 2004 Elsevier B.V. All rights reserved.

Extreme waves under Hurricane Ivan.

PubMed

Wang, David W; Mitchell, Douglas A; Teague, William J; Jarosz, Ewa; Hulbert, Mark S

2005-08-05

Hurricane Ivan, a category 4 storm, passed directly over six wave-tide gauges deployed by the Naval Research Laboratory on the outer continental shelf in the northeastern Gulf of Mexico. Waves were observed with significant wave heights reaching 17.9 meters and maximum crest-to-trough individual wave heights of 27.7 meters (91 feet). Analysis suggests that significant wave heights likely surpassed 21 meters (69 feet) and that maximum crest-to-trough individual wave heights exceeded 40 meters (132 feet) near the eyewall.

Effect of working hours on cardiovascular-autonomic nervous functions in engineers in an electronics manufacturing company.

PubMed

Sasaki, T; Iwasaki, K; Oka, T; Hisanaga, N; Ueda, T; Takada, Y; Fujiki, Y

1999-01-01

A field survey of 147 engineers (23-49 years) in an electronics manufacturing company was conducted to investigate the effect of working hours on cardiovascular-autonomic nervous functions (urinary catecholamines, heart rate variability and blood pressure). The subjects were divided into 3 groups by age: 23-29 (n = 49), 30-39 (n = 74) and 40-49 (n = 24) year groups. Subjects in each age group were further divided into shorter (SWH) and longer (LWH) working hour subgroups according to the median of weekly working hours. In the 30-39 year group, urinary noradrenaline in the afternoon for LWH was significantly lower than that for SWH and a similar tendency was found in the LF/HF ratio of heart rate variability at rest. Because these two autonomic nervous indices are related to sympathetic nervous activity, the findings suggested that sympathetic nervous activity for LWH was lower than that for SWH in the 30-39 year group. Furthermore, there were significant relationships both between long working hours and short sleeping hours, and between short sleeping hours and high complaint rates of "drowsiness and dullness" in the morning in this age group. Summarizing these results, it appeared that long working hours might lower sympathetic nervous activity due to chronic sleep deprivation.

Oceanic-wave-measurement system

NASA Technical Reports Server (NTRS)

Holmes, J. F.; Miles, R. T.

1980-01-01

Barometer mounted on bouy senses wave heights. As wave motion raises and lowers barometer, pressure differential is proportional to wave height. Monitoring circuit samples barometer output every half cycle of wave motion and adds magnitudes of adjacent positive and negative peaks. Resulting output signals, proportional to wave height, are transmitted to central monitoring station.

Movable-Bed Laboratory Experiments Comparing Radiation Stress and Energy Flux Factor as Predictors of Longshore Transport Rate.

DTIC Science & Technology

1981-04-01

acceleration of gravity H wave height H average wave height Hrms root-mean-square wave height Hs significant wave height IX longshore transport rate in...wave height, H, measured during the tests (and discussed later in Section IV) is equal to Hrms . By rewriting equation (4), S ( Cg cos.) C (7) xy 8 Cg...only for conditions where H equals Hrms * 2. Energy Flux. In literature, the longshore transport rate has been empirically related most frequently to a

Examining student-generated questions in an elementary science classroom

NASA Astrophysics Data System (ADS)

Diaz, Juan Francisco, Jr.

This study was conducted to better understand how teachers use an argument-based inquiry technique known as the Science Writing Heuristic (SWH) approach to address issues on teaching, learning, negotiation, argumentation, and elaboration in an elementary science classroom. Within the SWH framework, this study traced the progress of promoting argumentation and negotiation (which led to student-generated questions) during a discussion in an elementary science classroom. Speech patterns during various classroom scenarios were analyzed to understand how teacher--student interactions influence learning. This study uses a mixture of qualitative and quantitative methods. The qualitative aspect of the study is an analysis of teacher--student interactions in the classroom using video recordings. The quantitative aspect uses descriptive statistics, tables, and plots to analyze the data. The subjects in this study were fifth grade students and teachers from an elementary school in the Midwest, during the academic years 2007/2008 and 2008/2009. The three teachers selected for this study teach at the same Midwestern elementary school. These teachers were purposely selected because they were using the SWH approach during the two years of the study. The results of this study suggest that all three teachers moved from using teacher-generated questions to student-generated questions as they became more familiar with the SWH approach. In addition, all three promoted the use of the components of arguments in their dialogs and discussions and encouraged students to elaborate, challenge, and rebut each other's ideas in a non-threatening environment. This research suggests that even young students, when actively participating in class discussions, are capable of connecting their claims and evidence and generating questions of a higher-order cognitive level. These findings demand the implementation of more professional development programs and the improvement in teacher education to help teachers confidently implement argumentative practices and develop pedagogical strategies to help students use them.

Experimental infection with H1N1 European swine influenza virus protects pigs from an infection with the 2009 pandemic H1N1 human influenza virus.

PubMed

Busquets, Núria; Segalés, Joaquim; Córdoba, Lorena; Mussá, Tufaria; Crisci, Elisa; Martín-Valls, Gerard E; Simon-Grifé, Meritxell; Pérez-Simó, Marta; Pérez-Maíllo, Monica; Núñez, Jose I; Abad, Francesc X; Fraile, Lorenzo; Pina, Sonia; Majó, Natalia; Bensaid, Albert; Domingo, Mariano; Montoya, María

2010-01-01

The recent pandemic caused by human influenza virus A(H1N1) 2009 contains ancestral gene segments from North American and Eurasian swine lineages as well as from avian and human influenza lineages. The emergence of this A(H1N1) 2009 poses a potential global threat for human health and the fact that it can infect other species, like pigs, favours a possible encounter with other influenza viruses circulating in swine herds. In Europe, H1N1, H1N2 and H3N2 subtypes of swine influenza virus currently have a high prevalence in commercial farms. To better assess the risk posed by the A(H1N1) 2009 in the actual situation of swine farms, we sought to analyze whether a previous infection with a circulating European avian-like swine A/Swine/Spain/53207/2004 (H1N1) influenza virus (hereafter referred to as SwH1N1) generated or not cross-protective immunity against a subsequent infection with the new human pandemic A/Catalonia/63/2009 (H1N1) influenza virus (hereafter referred to as pH1N1) 21 days apart. Pigs infected only with pH1N1 had mild to moderate pathological findings, consisting on broncho-interstitial pneumonia. However, pigs inoculated with SwH1N1 virus and subsequently infected with pH1N1 had very mild lung lesions, apparently attributed to the remaining lesions caused by SwH1N1 infection. These later pigs also exhibited boosted levels of specific antibodies. Finally, animals firstly infected with SwH1N1 virus and latter infected with pH1N1 exhibited undetectable viral RNA load in nasal swabs and lungs after challenge with pH1N1, indicating a cross-protective effect between both strains. © INRA, EDP Sciences, 2010.

33 CFR 177.07 - Other unsafe conditions.

Code of Federal Regulations, 2012 CFR

2012-07-01

...) The wave height within the Regulated Boating Area is 4 feet or greater; or (2) The wave height within the Regulated Boating Area is equal to or greater than the wave height determined by the formula L/10... from the lowest point along the upper strake edge to the surface of the water. W=Maximum wave height in...

33 CFR 177.07 - Other unsafe conditions.

Code of Federal Regulations, 2011 CFR

2011-07-01

...) The wave height within the Regulated Boating Area is 4 feet or greater; or (2) The wave height within the Regulated Boating Area is equal to or greater than the wave height determined by the formula L/10... from the lowest point along the upper strake edge to the surface of the water. W=Maximum wave height in...

33 CFR 177.07 - Other unsafe conditions.

Code of Federal Regulations, 2013 CFR

2013-07-01

...) The wave height within the Regulated Boating Area is 4 feet or greater; or (2) The wave height within the Regulated Boating Area is equal to or greater than the wave height determined by the formula L/10... from the lowest point along the upper strake edge to the surface of the water. W=Maximum wave height in...

Investigation of the relationship between hurricane waves and extreme runup

NASA Astrophysics Data System (ADS)

Thompson, D. M.; Stockdon, H. F.

2006-12-01

In addition to storm surge, the elevation of wave-induced runup plays a significant role in forcing geomorphic change during extreme storms. Empirical formulations for extreme runup, defined as the 2% exceedence level, are dependent on some measure of significant offshore wave height. Accurate prediction of extreme runup, particularly during hurricanes when wave heights are large, depends on selecting the most appropriate measure of wave height that provides energy to the nearshore system. Using measurements from deep-water wave buoys results in an overprediction of runup elevation. Under storm forcing these large waves dissipate across the shelf through friction, whitecapping and depth-limited breaking before reaching the beach and forcing swash processes. The use of a local, shallow water wave height has been shown to provide a more accurate estimate of extreme runup elevation (Stockdon, et. al. 2006); however, a specific definition of this local wave height has yet to be defined. Using observations of nearshore waves from the U.S. Army Corps of Engineers' Field Research Facility (FRF) in Duck, NC during Hurricane Isabel, the most relevant measure of wave height for use in empirical runup parameterizations was examined. Spatial and temporal variability of the hurricane wave field, which made landfall on September 18, 2003, were modeled using SWAN. Comparisons with wave data from FRF gages and deep-water buoys operated by NOAA's National Data Buoy Center were used for model calibration. Various measures of local wave height (breaking, dissipation-based, etc.) were extracted from the model domain and used as input to the runup parameterizations. Video based observations of runup collected at the FRF during the storm were used to ground truth modeled values. Assessment of the most appropriate measure of wave height can be extended over a large area through comparisons to observations of storm- induced geomorphic change.

The Ocean Surface Topography Sentinel-6/Jason-CS Mission

NASA Astrophysics Data System (ADS)

Giulicchi, L.; Cullen, R.; Donlon, C.; Vuilleumier@esa int, P.

2016-12-01

The Sentinel-6/Jason-CS mission consists of two identical satellites flying in sequence and designed to provide operational measurements of sea surface height significant wave high and wind speed to support operational oceanography and climate monitoring. The mission will be the latest in a series of ocean surface topography missions that will span nearly three decades. They follow the altimeters on- board TOPEX/Poseidon through to Jason-3 (launched in January 2016). Jason-CS will continue to fulfil objectives of the reference series whilst introducing a major enhancement in capability providing the operational and science oceanographic community with the state of the art in terms of spacecraft, measurement instrumentation design thus securing optimal operational and science data return. As a secondary objective the mission will also include Radio Occultation user services. Each satellite will be launched sequentially into the Jason orbit (up to 66 latitude) respectively in 2020 and 2025. The principle payload instrument is a high precision Ku/C band radar altimeter with retrieval of geophysical parameters (surface elevation, wind speed and SWH) from the altimeter data require supporting measurements: a DORIS receiver for Precise Orbit Determination; The Climate Quality Advanced Microwave Radiometer (AMR-C) for high stability path delay correction. Orbit tracking data are also provided by GPS & LRA. An additional GPS receiver will be dedicated to radio-occultation measurements. The programme is a part of the European Community Copernicus initiative, whose objective is to support Europe's goals regarding sustainable development and global governance of the environment by providing timely and quality data, information, services and knowledge. The Sentinel-6/Jason-CS in particular is a cooperative mission with contributions from NASA, NOAA, EUMETSAT, ESA, CNES and the European Union.

Wave attenuation in the shallows of San Francisco Bay

USGS Publications Warehouse

Lacy, Jessica R.; MacVean, Lissa J.

2016-01-01

Waves propagating over broad, gently-sloped shallows decrease in height due to frictional dissipation at the bed. We quantified wave-height evolution across 7 km of mudflat in San Pablo Bay (northern San Francisco Bay), an environment where tidal mixing prevents the formation of fluid mud. Wave height was measured along a cross shore transect (elevation range−2mto+0.45mMLLW) in winter 2011 and summer 2012. Wave height decreased more than 50% across the transect. The exponential decay coefficient λ was inversely related to depth squared (λ=6×10−4h−2). The physical roughness length scale kb, estimated from near-bed turbulence measurements, was 3.5×10−3 m in winter and 1.1×10−2 m in summer. Estimated wave friction factor fw determined from wave-height data suggests that bottom friction dominates dissipation at high Rew but not at low Rew. Predictions of near-shore wave height based on offshore wave height and a rough formulation for fw were quite accurate, with errors about half as great as those based on the smooth formulation for fw. Researchers often assume that the wave boundary layer is smooth for settings with fine-grained sediments. At this site, use of a smooth fw results in an underestimate of wave shear stress by a factor of 2 for typical waves and as much as 5 for more energetic waves. It also inadequately captures the effectiveness of the mudflats in protecting the shoreline through wave attenuation.

The effect of 5E-SWH learning model on students' view of nature of science

NASA Astrophysics Data System (ADS)

Sinthuwa, Waralee; Sangpradit, Theerapong

2018-01-01

View of Nature of Science (NOS) is one of key factors to support students' scientific literacy. So, it includes in scientific learning goals internationally. As in the literature, the many potential benefits associated with appropriate view of NOS. For instance, it influences students' learning achievement in science and lets students see how science connected to their real world. The aim of this study was to develop the 5E-SWH learning model to enhance 12th grade students' view of NOS. Eighty-eight students participated in this study. They were separated into two groups. Forty-four students had learnt biology by using 5E-SWH learning unit, but another group had learnt by using traditional 5E. View of NOS questionnaire that was adapted from the Views of NOS Questionnaire (VNOS-C) was applied with the both groups as pretest and posttest. The questionnaire consisted of ten open-ended items. The semi-structured interview protocol was also used with thirty students and feedback on the lesson record was provided in order to triangulate students' view of NOS. The analyzed results were approved by peer review. In addition, the during the implementation, data from voice recorder was transcribed and used discourse analysis to show students' NOS views. There were three aspects that relate to genetics technology content. These aspects included the subjective, empirical, and social and culture. Students' responses were categorized into 3 groups including informed, adequate and inadequate view. The results showed that the majority of participants held inadequate views of the subjective and empirical aspect at the beginning of the study. In addition, almost student as well as held adequate view of the social and culture aspect and they had misconception in some target NOS aspects. After that, they had learnt genetics technology content by using 5E-SWH learning model for 15 periods (50 min/ period). Both student groups' view of NOS was compared with each other. The study showed that the group that using 5E-SWH learning model develop their NOS view more than the control group that learnt through on 5E. The experimental group improved to informed view as following 45.46% subjective, 31.82% empirical and 59.09% social and culture. In addition, more than 50% of students shifted their view of NOS to better group in all target aspects. 25.76% of students shifted their view of NOS from inadequate to adequate view and 27.27% of students shifted their view of NOS from inadequate to informed view. 21.21% of students shifted their view of NOS from adequate to informed view. Furthermore, it showed their view of NOS improvement by conversation in class. The feedback on the lesson record was also support that students' view of NOS were improved by engaging in 5E-SWH learning unit. However, some students' comment on the lesson showed that they were still familiar with lecture. Therefore, it was the factor that we should concern in view of NOS development. The implications of this research for teachers were that the learning model could use to be the guideline to teach NOS integrate content in the classroom and they can use this learning model to design lesson plan in science.

Evaluation of the wave measurement in a stormy sea by the Along-Track interferometry SAR

NASA Astrophysics Data System (ADS)

Kojima, S.

2015-12-01

NICT developed the along-track interferometry SAR (AT-InSAR) system to detect the running cars and ships and measure sea surface velocity in 2011. The preliminary experiments for the running truck and ship were performed and it confirmed that the system performance was satisfactory to its specifications. In addition, a method to estimate the wave height from the sea surface velocity measured by the AT-InSAR was developed. The preliminary wave height observation was performed in a calm sea, and it was confirmed that the wave height could be estimated from the measured sea surface velocity. The purpose of this study is to check the capability of the ocean waves observation in a stormy sea by the AT-InSAR. Therefore, the ocean wave observation was performed under the low atmospheric pressure. The observation area is the sea surface at 10 km off the coast of Kushiro, south-east to Hokaido, JAPAN on the 4th of March 2015. The wind speed was 8〜10m/s during the observation, and the significant wave height and period were 1.5m and 6.0s. The observation was performed in 2 directions and the accuracy of the estimation results were checked. The significant wave height and period measured by the AT-InSAR agreed with it measured by the wave gage located close to this observation area. In addition, it was confirmed that there were no irregular wave heights in the distribution of the estimated wave height. As a result, it became clear that the AT-InSAR could observe the wave height in a stormy sea.

Physical Model Study of Wave Action in New Thomsen Harbor, Sitka, Alaska

DTIC Science & Technology

2008-02-01

approached from the southwest. DISCLAIMER: The contents of this report are not to be used for advertising , publication, or promotional purposes...Wave height and period for irregular wave conditions refer to Hm0 and Tp, respectively. For mono- chromatic waves, wave height is the actual height...sec, respectively. Plotted along with the Group 12 results are corresponding tests from Group 13 that used mono- chromatic waves. Looking only at

Changes in the extreme wave heights over the Baltic Sea

NASA Astrophysics Data System (ADS)

Kudryavtseva, Nadia; Soomere, Tarmo

2017-04-01

Storms over the Baltic Sea and northwestern Europe have a large impact on the population, offshore industry, and shipping. The understanding of extreme events in sea wave heights and their change due to the climate change and variability is critical for assessment of flooding risks and coastal protection. The BACCII Assessment of Climate Change for the Baltic Sea Basin showed that the extreme events analysis of wind waves is currently not very well addressed, as well as satellite observations of the wave heights. Here we discuss the analysis of all existing satellite altimetry data over the Baltic Sea Basin regarding extremes in the wave heights. In this talk for the first time, we present an analysis of 100-yr return periods, fitted generalized Pareto and Weibull distributions, number, and frequency of extreme events in wave heights in the Baltic Sea measured by the multi-mission satellite altimetry. The data span more than 23 years and provide an excellent spatial coverage over the Baltic Sea, allowing to study in details spatial variations and changes in extreme wave heights. The analysis is based on an application of the Initial Distribution Method, Annual Maxima method and Peak-Over-Threshold approach to satellite altimetry data, all validated in comparison with in-situ wave height measurements. Here we show that the 100-yr return periods of wave heights show significant spatial changes over the Baltic Sea indicating a decrease in the southern part of the Baltic Sea and an increase in adjacent areas, which can significantly affect coast vulnerability. Here we compare the observed shift with storm track database data and discuss a spatial correlation and possible connection between the changes in the storm tracks over the Baltic Sea and the change in the extreme wave heights.

An empirical determination of the effects of sea state bias on Seasat altimetry

NASA Technical Reports Server (NTRS)

Born, G. H.; Richards, M. A.; Rosborough, G. W.

1982-01-01

A linear empirical model has been developed for the correction of sea state bias effects, in Seasat altimetry data altitude measurements, that are due to (1) electromagnetic bias caused by the fact that ocean wave troughs reflect the altimeter signal more strongly than the crests, shifting the apparent mean sea level toward the wave troughs, and (2) an independent instrument-related bias resulting from the inability of height corrections applied in the ground processor to compensate for simplifying assumptions made for the processor aboard Seasat. After applying appropriate corrections to the altimetry data, an empirical model for the sea state bias is obtained by differencing significant wave height and height measurements from coincident ground tracks. Height differences are minimized by solving for the coefficient of a linear relationship between height differences and wave height differences that minimize the height differences. In more than 50% of the 36 cases examined, 7% of the value of significant wave height should be subtracted for sea state bias correction.

Experimental Studies on Wave Interactions of Partially Perforated Wall under Obliquely Incident Waves

PubMed Central

Lee, Jong-In; Kim, Young-Taek; Shin, Sungwon

2014-01-01

This study presents wave height distribution in terms of stem wave evolution phenomena on partially perforated wall structures through three-dimensional laboratory experiments. The plain and partially perforated walls were tested to understand their effects on the stem wave evolution under the monochromatic and random wave cases with the various wave conditions, incident angle (from 10 to 40 degrees), and configurations of front and side walls. The partially perforated wall reduced the relative wave heights more effectively compared to the plain wall structure. Partially perforated walls with side walls showed a better performance in terms of wave height reduction compared to the structure without the side wall. Moreover, the relative wave heights along the wall were relatively small when the relative chamber width is large, within the range of the chamber width in this study. The wave spectra showed a frequency dependency of the wave energy dissipation. In most cases, the existence of side wall is a more important factor than the porosity of the front wall in terms of the wave height reduction even if the partially perforated wall was still effective compared to the plain wall. PMID:25254260

Experimental studies on wave interactions of partially perforated wall under obliquely incident waves.

PubMed

Lee, Jong-In; Kim, Young-Taek; Shin, Sungwon

2014-01-01

This study presents wave height distribution in terms of stem wave evolution phenomena on partially perforated wall structures through three-dimensional laboratory experiments. The plain and partially perforated walls were tested to understand their effects on the stem wave evolution under the monochromatic and random wave cases with the various wave conditions, incident angle (from 10 to 40 degrees), and configurations of front and side walls. The partially perforated wall reduced the relative wave heights more effectively compared to the plain wall structure. Partially perforated walls with side walls showed a better performance in terms of wave height reduction compared to the structure without the side wall. Moreover, the relative wave heights along the wall were relatively small when the relative chamber width is large, within the range of the chamber width in this study. The wave spectra showed a frequency dependency of the wave energy dissipation. In most cases, the existence of side wall is a more important factor than the porosity of the front wall in terms of the wave height reduction even if the partially perforated wall was still effective compared to the plain wall.

Inservice teachers' implementation of the Science Writing Heuristic as a tool for professional growth

NASA Astrophysics Data System (ADS)

Omar, Sozan H.

According to the National Science Standards, science educators have been calling for the inclusion of inquiry-based approaches in science classrooms as a reform for science instruction. Teachers' reluctance to implement inquiry-based approaches may be attributed to the different interpretations of the underpinning theory. Any efforts to help teachers implement effective teaching approaches, therefore, should not target merely additive skills; rather, such efforts should foster fundamental changes of beliefs, knowledge, and habits of practice that teachers deeply hold. This study is a part of a bigger project known as the Science Writing Heuristic (SWH) Partnership Professional Development Project, conducted at Iowa State University in association with the Iowa Department of Education to help improve science teaching. The aim of the project is to help in service science teachers understand and apply a student-oriented instructional approach, using the SWH. The framework of the SWH emphasizes the role of classroom dialogical discussion in students' learning. The role of the teacher when implementing constructivist approaches represented in a student-oriented instruction, differs markedly from traditional approaches, and hence there is a need to study the changes in teaching practice when using this specific tool. The methodological framework of this study combined qualitative and quantitative methods. Interpretative case studies for 18 science teachers are presented. A triangulation strategy was used to provide support for the qualitative findings using three different data collection approaches: observation, questionnaire, and interviews. Quantitative data in the form of student performance on higher order conceptual questions and total test scores were collected. Teachers varied in their implementation of the SWH. Three criteria were constructed to define teachers' levels of implementation: epistemological belief, pedagogical practice, and teacher content knowledge. Different components were included within each criterion, with three scales used to rank each teacher's implementation within each criterion. The study is pointing to the importance of assisting science teachers with effective pedagogical strategies if there is to be an impact on students' performance on tests. This project was undertaken with partnerships between schools, Area Educational Agencies, and the University. Such partnerships need to be built to promote successful change to science teaching.

Empirical Guidelines for Use of Irregular Wave Model to Estimate Nearshore Wave Height.

DTIC Science & Technology

1982-07-01

height, the easier to use tech- nique presented by McClenan (1975) was employed. The McClenan technique uti- lizes a monogram which was constructed from...the SPM equations and gives the same results. The inputs to the monogram technique are the period, the deep- water wave height, the deepwater wave

Challenges in Defining Tsunami Wave Height

NASA Astrophysics Data System (ADS)

Stroker, K. J.; Dunbar, P. K.; Mungov, G.; Sweeney, A.; Arcos, N. P.

2017-12-01

The NOAA National Centers for Environmental Information (NCEI) and co-located World Data Service for Geophysics maintain the global tsunami archive consisting of the historical tsunami database, imagery, and raw and processed water level data. The historical tsunami database incorporates, where available, maximum wave heights for each coastal tide gauge and deep-ocean buoy that recorded a tsunami signal. These data are important because they are used for tsunami hazard assessment, model calibration, validation, and forecast and warning. There have been ongoing discussions in the tsunami community about the correct way to measure and report these wave heights. It is important to understand how these measurements might vary depending on how the data were processed and the definition of maximum wave height. On September 16, 2015, an 8.3 Mw earthquake located 48 km west of Illapel, Chile generated a tsunami that was observed all over the Pacific region. We processed the time-series water level data for 57 tide gauges that recorded this tsunami and compared the maximum wave heights determined from different definitions. We also compared the maximum wave heights from the NCEI-processed data with the heights reported by the NOAA Tsunami Warning Centers. We found that in the near field different methods of determining the maximum tsunami wave heights could result in large differences due to possible instrumental clipping. We also found that the maximum peak is usually larger than the maximum amplitude (½ peak-to-trough), but the differences for the majority of the stations were <20 cm. For this event, the maximum tsunami wave heights determined by either definition (maximum peak or amplitude) would have validated the forecasts issued by the NOAA Tsunami Warning Centers. Since there is currently only one field in the NCEI historical tsunami database to store the maximum tsunami wave height, NCEI will consider adding an additional field for the maximum peak measurement.

Challenges in Defining Tsunami Wave Heights

NASA Astrophysics Data System (ADS)

Dunbar, Paula; Mungov, George; Sweeney, Aaron; Stroker, Kelly; Arcos, Nicolas

2017-08-01

The National Oceanic and Atmospheric Administration (NOAA) National Centers for Environmental Information (NCEI) and co-located World Data Service for Geophysics maintain the global tsunami archive consisting of the historical tsunami database, imagery, and raw and processed water level data. The historical tsunami database incorporates, where available, maximum wave heights for each coastal tide gauge and deep-ocean buoy that recorded a tsunami signal. These data are important because they are used for tsunami hazard assessment, model calibration, validation, and forecast and warning. There have been ongoing discussions in the tsunami community about the correct way to measure and report these wave heights. It is important to understand how these measurements might vary depending on how the data were processed and the definition of maximum wave height. On September 16, 2015, an 8.3 M w earthquake located 48 km west of Illapel, Chile generated a tsunami that was observed all over the Pacific region. We processed the time-series water level data for 57 coastal tide gauges that recorded this tsunami and compared the maximum wave heights determined from different definitions. We also compared the maximum wave heights from the NCEI-processed data with the heights reported by the NOAA Tsunami Warning Centers. We found that in the near field different methods of determining the maximum tsunami wave heights could result in large differences due to possible instrumental clipping. We also found that the maximum peak is usually larger than the maximum amplitude (½ peak-to-trough), but the differences for the majority of the stations were <20 cm. For this event, the maximum tsunami wave heights determined by either definition (maximum peak or amplitude) would have validated the forecasts issued by the NOAA Tsunami Warning Centers. Since there is currently only one field in the NCEI historical tsunami database to store the maximum tsunami wave height for each tide gauge and deep-ocean buoy, NCEI will consider adding an additional field for the maximum peak measurement.

Small-scale open ocean currents have large effects on wind wave heights

NASA Astrophysics Data System (ADS)

Ardhuin, Fabrice; Gille, Sarah T.; Menemenlis, Dimitris; Rocha, Cesar B.; Rascle, Nicolas; Chapron, Bertrand; Gula, Jonathan; Molemaker, Jeroen

2017-06-01

Tidal currents and large-scale oceanic currents are known to modify ocean wave properties, causing extreme sea states that are a hazard to navigation. Recent advances in the understanding and modeling capability of open ocean currents have revealed the ubiquitous presence of eddies, fronts, and filaments at scales 10-100 km. Based on realistic numerical models, we show that these structures can be the main source of variability in significant wave heights at scales less than 200 km, including important variations down to 10 km. Model results are consistent with wave height variations along satellite altimeter tracks, resolved at scales larger than 50 km. The spectrum of significant wave heights is found to be of the order of 70>>2/>(g2>>2>) times the current spectrum, where >> is the spatially averaged significant wave height, >> is the energy-averaged period, and g is the gravity acceleration. This variability induced by currents has been largely overlooked in spite of its relevance for extreme wave heights and remote sensing.