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Full-Text Articles in Life Sciences
Using Lidar Elevation Data To Develop A Topobathymetric Digital Elevation Model For Sub-Grid Inundation Modeling At Langley Research Center, Jon Derek Loftis, Harry V. Wang, Rj Deyoung, Wb Ball
Using Lidar Elevation Data To Develop A Topobathymetric Digital Elevation Model For Sub-Grid Inundation Modeling At Langley Research Center, Jon Derek Loftis, Harry V. Wang, Rj Deyoung, Wb Ball
VIMS Articles
Technological progression in light detection and ranging permits the production of highly detailed digital elevation models, which are useful in sub-grid hydrodynamic modeling applications. Sub-grid modeling technology is capable of incorporating these high-resolution lidar-derived elevation measurements into the conventional hydrodynamic modeling framework to resolve detailed topographic features for inclusion in a hydrological transport model for runoff simulations. The horizontal resolution and vertical accuracy of the digital elevation model is augmented via inclusion of these lidar elevation values on a nested 5-m sub-grid within each coarse computational grid cell. This aids in resolving ditches and overland drainage infrastructure at Langley Research …
Levels, Sources And Chemical Fate Of Persistent Organic Pollutants In The Atmosphere And Snow Along The Western Antarctic Peninsula, Ma Khairy, Jl Luek, R Dickhut, R Lohmann
Levels, Sources And Chemical Fate Of Persistent Organic Pollutants In The Atmosphere And Snow Along The Western Antarctic Peninsula, Ma Khairy, Jl Luek, R Dickhut, R Lohmann
VIMS Articles
The Antarctic continent is among the most pristine regions; yet various organic contaminants have been measured there routinely. Air and snow samples were collected during the austral spring (October November, 2010) along the western Antarctic Peninsula and analyzed for organochlorine pesticides (OCPs), polychlorinated biphenyls (PCBs) and polybrominated diphenyl ethers (PBDEs) to assess the relative importance of long-range transport versus local primary or secondary emissions. Highest concentrations of PCBs, PBDEs and DDTs were observed in the glacier's snow sample, highlighting the importance of melting glaciers as a possible secondary source of legacy pollutants to the Antarctic. In the atmosphere, contaminants were …
Water Residence Time In Chesapeake Bay For 1980-2012, Jb Du, Jian Shen
Water Residence Time In Chesapeake Bay For 1980-2012, Jb Du, Jian Shen
VIMS Articles
Concerns have grown over the increase of nutrients and pollutants discharged into the estuaries and coastal seas. The retention and export of these materials inside a system depends on the residence time (RT). A long-term simulation of time-varying RT of the Chesapeake Bay was conducted over the period from 1980 to 2012. The 33-year simulation results show that the mean RT of the entire Chesapeake Bay system ranges from 110 to 264 days, with an average value of 180 days. The RT was larger in the bottom layers than in the surface layers due to the persistent stratification and estuarine …
Complex Coastal Change In Response To Autogenic Basin Infilling: An Example From A Sub-Tropical Holocene Strandplain, Christopher J. Hein, Dm Fitzgerald, Lhp De Souza, Iy Georgiou, Iv Buynevich, Et Al.
Complex Coastal Change In Response To Autogenic Basin Infilling: An Example From A Sub-Tropical Holocene Strandplain, Christopher J. Hein, Dm Fitzgerald, Lhp De Souza, Iy Georgiou, Iv Buynevich, Et Al.
VIMS Articles
Thick bay-fill sequences that often culminate in strandplain development serve as important sedimentary archives of land-ocean interaction, although distinguishing between internal and external forcings is an ongoing challenge. This study employs sediment cores, ground-penetrating radar surveys, radiocarbon dates, palaeogeographic reconstructions and hydrodynamic modelling to explore the role of autogenic processes - notably a reduction in wave energy in response to coastal embayment infilling - in coastal evolution and shoreline morphodynamics. Following a regional 2 to 4m highstand at ca 58ka, the 75km(2) Tijucas Strandplain in southern Brazil built from fluvial sediments deposited into a semi-enclosed bay. Holocene regressive deposits are …
Unstructured-Grid Model For The North Sea And Baltic Sea: Validation Against Observations, Yinglong J. Zhang, Ev Stanev, S Grashorn
Unstructured-Grid Model For The North Sea And Baltic Sea: Validation Against Observations, Yinglong J. Zhang, Ev Stanev, S Grashorn
VIMS Articles
A new unstructured grid model and its application to the North Sea and Baltic Sea are described. The research focus is on the dynamics in the two basins and in the multiple straits connecting them and more specifically on how the model replicates the temporal and spatial variability of physical processes. The comparison against observed data indicates the realism in the simulations of the exchange flows. The simulations demonstrated that in contrast to the tidal variability which decreases in the strait, the role of the barotropic forcing due to weather systems increases. In this zone reversal of transport is well …
Seamless Cross-Scale Modeling With Schism, Yinglong J. Zhang, Fei Ye, Ev Stanev, S Grashorn
Seamless Cross-Scale Modeling With Schism, Yinglong J. Zhang, Fei Ye, Ev Stanev, S Grashorn
VIMS Articles
We present a new 3D unstructured-grid model (SCHISM) which is an upgrade from an existing model (SELFE). The new advection scheme for the momentum equation includes an iterative smoother to reduce excess mass produced by higher-order kriging method, and a new viscosity formulation is shown to work robustly for generic unstructured grids and effectively filter out spurious modes without introducing excessive dissipation. A new higher-order implicit advection scheme for transport (TVD2) is proposed to effectively handle a wide range of Courant numbers as commonly found in typical cross-scale applications. The addition of quadrangular elements into the model, together with a …