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Climate Variability and Its Impact on Forest Hydrology on South Carolina Coastal Plain, USA  [PDF]
Zhaohua Dai,Devendra M. Amatya,Ge Sun,Carl C. Trettin,Changsheng Li,Harbin Li
Atmosphere , 2011, DOI: 10.3390/atmos2030330
Abstract: Understanding the changes in hydrology of coastal forested wetlands induced by climate change is fundamental for developing strategies to sustain their functions and services. This study examined 60 years of climatic observations and 30 years of hydrological data, collected at the Santee Experimental Forest (SEF) in coastal South Carolina. We also applied a physically-based, distributed hydrological model (MIKE SHE) to better understand the hydrological responses to the observed climate variability. The results from both observation and simulation for the paired forested watershed systems indicated that the forest hydrology was highly susceptible to change due to climate change. The stream flow and water table depth was substantially altered with a change in precipitation. Both flow and water table level decreased with a rise in temperature. The results also showed that hurricanes substantially influenced the forest hydrological patterns for a short time period (several years) as a result of forest damage.
Two Dimensional Hydrodynamic Modelling of Northern Bay of Bengal Coastal Waters  [PDF]
Misbah Uddin, Jahir Bin Alam, Zahirul Haque Khan, G. M. Jahid Hasan, Tauhidur Rahman
Computational Water, Energy, and Environmental Engineering (CWEEE) , 2014, DOI: 10.4236/cweee.2014.34015
Abstract: Mathematical models have advancement to a point where they are considered to be an effective tool for simulating natural phenomena in coastal regions. This paper discusses the development of Bay of Bengal Model (BoBM), updating of the model with the recent bathymetry and shore line of islands and coastline and upgrading from rectangular grid to finer size of mesh grids by using latest version of MIKE21 FM modeling system. This model is very useful for the hydrodynamic study in the coastal region of Bangladesh. The article also presents the model set-up, boundary conditions and few calibration results of the model. The model applications clearly show the variation of the flow structure, their speed and direction separately for monsoon and dry season around the model area which covers the northern part of Bay of Bengal.
How to Distinguish Hydrodynamic Models Utilizing Particle Correlations and Spectra ?  [PDF]
T. Csorgo,S. Nickerson,D. Kiang
Physics , 1996,
Abstract: We demonstrate on examples that a simultaneous study of the Bose-Einstein correlation function and the invariant momentum distribution can be very useful in distinguishing various hydrodynamic models, which describe separately the short-range correlations in high energy hadronic reactions as measured by the NA22 collaboration. We also analyze Bose-Einstein correlation functions, measured by the NA44 experiment at CERN SPS, in the context of the core-halo model.
Evaluating meteorological climate model inputs to improve coastal hydrodynamic studies
D. Bellafiore, E. Bucchignani, S. Gualdi, S. Carniel, V. Djurdjevi ,G. Umgiesser
Advances in Science and Research (ASR) , 2011, DOI: 10.5194/asr-6-227-2011
Abstract: This work compares meteorological results from different regional climate model (RCM) implementations in the Mediterranean area, with a focus on the northern Adriatic Sea. The need to use these datasets as atmospheric forcings (wind and atmospheric pressure fields) for coastal hydrodynamic models to assess future changes in the coastal hydrodynamics, is the basis of the presented analysis. It would allow the assessment of uncertainties due to atmospheric forcings in providing coastal current, surge and wave climate changes from future implementations of hydrodynamic models. Two regional climate models, with different spatial resolutions, downscaled from two different global climate models (whose atmospheric components are, respectively, ECHAM4 and ECHAM5), were considered. In particular, the RCM delivered wind and atmospheric pressure fields were compared with measurements at four stations along the Italian Adriatic coast. The analyses were conducted using a past control period, 1960–1990, and the A1B IPCC future scenario (2070–2100). The chosen scenario corresponds to a world of very rapid economic and demographic growth that peaks in mid-century, with a rapid introduction of new efficient technologies, which balance fossil and non-fossil resources (IPCC, 2007). Consideration is given to the accuracy of each model at reproducing the basic statistics and the trends. The role of models' spatial resolution in reproducing global and local scale meteorological processes is also discussed. The Adriatic Sea climate is affected by the orography that produces a strengthening of north-eastern katabatic winds like bora. Therefore, spatial model resolution, both for orography and for a better resolution of coastline (Cavaleri et al., 2010), is one of the important factors in providing more realistic wind forcings for future hydrodynamic models implementations. However, also the characteristics in RCM setup and parameterization can explain differences between the datasets. The analysis from an ensemble of model implementation would provide more robust indications on climatic wind and atmospheric pressure variations. The scenario-control comparison shows a general increase in the mean atmospheric pressure values while a decrease in mean wind speed and in extreme wind events is seen, particularly for the datasets with higher spatial resolution.
Multi-objective automatic calibration of hydrodynamic models utilizing inundation maps and gauge data
N. V. Dung, B. Merz, A. Bárdossy, T. D. Thang,H. Apel
Hydrology and Earth System Sciences (HESS) & Discussions (HESSD) , 2011,
Abstract: Automatic and multi-objective calibration of hydrodynamic models is – compared to other disciplines like e.g. hydrology – still underdeveloped. This has mainly two reasons: the lack of appropriate data and the large computational demand in terms of CPU-time. Both aspects are aggravated in large-scale applications. However, there are recent developments that improve the situation on both the data and computing side. Remote sensing, especially radar-based techniques proved to provide highly valuable information on flood extents, and in case high precision DEMs are present, also on spatially distributed inundation depths. On the computing side the use of parallelization techniques brought significant performance gains. In the presented study we build on these developments by calibrating a large-scale 1-dimensional hydrodynamic model of the whole Mekong Delta downstream of Kratie in Cambodia: we combined in-situ data from a network of river gauging stations, i.e. data with high temporal but low spatial resolution, with a series of inundation maps derived from ENVISAT Advanced Synthetic Aperture Radar (ASAR) satellite images, i.e. data with low temporal but high spatial resolution, in an multi-objective automatic calibration process. It is shown that an automatic, multi-objective calibration of hydrodynamic models, even of such complexity and on a large scale and complex as a model for the Mekong Delta, is possible. Furthermore, the calibration process revealed model deficiencies in the model structure, i.e. the representation of the dike system in Vietnam, which would have been difficult to detect by a standard manual calibration procedure.
Multi-objective automatic calibration of hydrodynamic models utilizing inundation maps and gauge data
N. V. Dung,B. Merz,A. Bárdossy,T. D. Thang
Hydrology and Earth System Sciences (HESS) & Discussions (HESSD) , 2011, DOI: 10.5194/hess-15-1339-2011
Abstract: Automatic and multi-objective calibration of hydrodynamic models is – compared to other disciplines like e.g. hydrology – still underdeveloped. This has mainly two reasons: the lack of appropriate data and the large computational demand in terms of CPU-time. Both aspects are aggravated in large-scale applications. However, there are recent developments that improve the situation on both the data and computing side. Remote sensing, especially radar-based techniques proved to provide highly valuable information on flood extents, and in case high precision DEMs are present, also on spatially distributed inundation depths. On the computing side the use of parallelization techniques brought significant performance gains. In the presented study we build on these developments by calibrating a large-scale 1-dimensional hydrodynamic model of the whole Mekong Delta downstream of Kratie in Cambodia: we combined in-situ data from a network of river gauging stations, i.e. data with high temporal but low spatial resolution, with a series of inundation maps derived from ENVISAT Advanced Synthetic Aperture Radar (ASAR) satellite images, i.e. data with low temporal but high spatial resolution, in an multi-objective automatic calibration process. It is shown that an automatic, multi-objective calibration of hydrodynamic models, even of such complexity and on a large scale and complex as a model for the Mekong Delta, is possible. Furthermore, the calibration process revealed model deficiencies in the model structure, i.e. the representation of the dike system in Vietnam, which would have been difficult to detect by a standard manual calibration procedure.
Multi-objective automatic calibration of hydrodynamic models utilizing inundation maps and gauge data
N. V. Dung,B. Merz,A. Bárdossy,T. D. Thang
Hydrology and Earth System Sciences Discussions , 2010, DOI: 10.5194/hessd-7-9173-2010
Abstract: Calibration of hydrodynamic models is – compared to other disciplines like e.g. hydrology – still underdeveloped. This has mainly two reasons: the lack of appropriate data and the large computational demand in terms of CPU-time. Both aspects are aggravated in large-scale applications. However, there are recent developments that improve the situation on both the data and computing side. Remote sensing, especially radar-based techniques proved to provide highly valuable information on flood extents, and in case high precision DEMs are present, also on spatially distributed inundation depths. On the computing side the use of parallelization techniques brought significant performance gains. In the presented study we build on these developments by calibrating a large-scale 1-D hydrodynamic model of the whole Mekong Delta downstream of Kratie in Cambodia: we combined in-situ data from a network of river gauging stations, i.e. data with high temporal but low spatial resolution, with a series of inundation maps derived from ENVISAT Advanced Synthetic Aperture Radar (ASAR) satellite images, i.e. data with low temporal but high spatial resolution, in an multi-objective automatic calibration process. It is shown that an automatic, multi-objective calibration of hydrodynamic models, even of such complexity and on a large scale and complex as a model for the Mekong Delta, is possible. Furthermore, the calibration process revealed model deficiencies in the model structure, i.e. the representation of the dike system in Vietnam, which would have been difficult to detect by a standard manual calibration procedure.
Qualitative Analysis Of The Coastal Strip South Of The Caspian Sea Waters And Determine Environmental Health Indicators In Coastal Projects Of Guilan
Ramin Nabizadeh,Masoud Binesh Brahmand,Kazem Naddefi,Ali Reza Mesdaghiniya
Iranian Journal of Health and Environment , 2012,
Abstract: Normal 0 false false false EN-US X-NONE AR-SA MicrosoftInternetExplorer4 Background and Objectives: Guilan province, with unique environmental values of the Caspian Sea is located in the southwest of Caspian Sea. Disposal of untreated domestic sewage, industrial and agricultural surface water cause pollution of the Caspian Sea region and endanger the health of swimmers. This study performed to determine the microbial contamination of coastal water in Guilan. Materials and Methods: In this work, 21 sampling point in the Caspian Sea littoral provinces of Guilan were selected and microbial contaminations were assessed using microbial indicators of fecal and total coliform. Parameters such as pH, temperature, and turbidity also monitored during the year. In this study, 122 samples were taken and then analyzed by statistical software. Results: The results showed that the average values of total coliform and fecal coliform were 234.8 and 60 MPN per 100 ml, respectively. The fecal pollution appeared to be high in some stations. Also significant relationship between temperature, turbidity and microbial contamination was observed (P< 0.05). Conclusion: The results revealed high total coliform in the two stations. The average fecal coliform of six stations were higher than the local standards. st1":*{behavior:url(#ieooui) } /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0cm 5.4pt 0cm 5.4pt; mso-para-margin:0cm; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:"Times New Roman"; mso-fareast-theme-font:minor-fareast; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:Arial; mso-bidi-theme-font:minor-bidi;}
Sediment and Shallow Coastal Water Detection Utilizing MODIS Land Channels over Gulf of Martaban  [cached]
Abd Rahman Mat Amin,Khiruddin Abdullah
Applied Physics Research , 2010, DOI: 10.5539/apr.v2n2p61
Abstract: Application of clear waters (Case 1) algorithm to satellite imagery acquired with Moderate Resolution Imaging Spectroradiometer (MODIS) over turbid coastal waters (Case 2) often results in negative water-leaving radiances over extended areas. Also, the maximum reflectances for ocean color channels are significantly smaller than those for the land channels at similar wavelengths. Because of that, at the bright coastal waters area, ocean color channels (0.488, 0.531 and 0.551 μm) often saturate. The saturation of this channels contribute to the lost of geophysical and biological activities in the data. So, in order to overcome this circumstance, it is reasonable to use MODIS land and atmosphere channels (1 to 7) to derive an algorithm for the detections of turbid and shallow coastal waters area. In order to improve aerosol retrieving algorithm over the ocean, an algorithm to mask out the turbid coastal water area need to be developed. In this paper, a simple algorithm to identify and mask shallow coastal water and high amounts of suspended sediment area in the Gulf of Martaban using MODIS L1B image is suggested and demonstrated. This algorithm uses log10 ratio of two MODIS solar channels that was originally designed for remote sensing over land and cloud properties (band 3 and band 4) centered at 0.47 and 0.55 μm respectively. Shallow coastal water and the area with high amount of suspended sediment are detected by our algorithm have been masked. The result of this algorithm is then evaluated by comparing the masked area with the true color image of the scene.
Operational Wave Now-and Forecast in the German Bight as a Basis for the Assessment of Wave-Induced Hydrodynamic Loads on Coastal Dikes Operational Wave Now-and Forecast in the German Bight as a Basis for the Assessment of Wave-Induced Hydrodynamic Loads on Coastal Dikes  [PDF]
DREIER Norman,FR?HLE Peter
- , 2017,
Abstract: The knowledge of the wave-induced hydrodynamic loads on coastal dikes including their temporal and spatial resolution on the dike in combination with actual water levels is of crucial importance of any risk-based early warning system. As a basis for the assessment of the wave-induced hydrodynamic loads, an operational wave now-and forecast system is set up that consists of i) available field measurements from the federal and local authorities and ii) data from numerical simulation of waves in the German Bight using the SWAN wave model. In this study, results of the hindcast of deep water wave conditions during the winter storm on 5–6 December, 2013(German name ‘Xaver') are shown and compared with available measurements. Moreover field measurements of wave run-up from the local authorities at a sea dike on the German North Sea Island of Pellworm are presented and compared against calculated wave run-up using the Eur Otop(2016) approach
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