A. K. M. Azad Hossain

Numerical modeling of surface flow and transport phenomena with applications to Lake Pontchartrain

Abstract This article presents the capabilities of a numerical model, CCHE2D, by using its application to study the response of a highly complex water system, Lake Pontchartrain, Louisiana, under extreme conditions of Hurricane Katrina in 2005 and the flood water release from Bonnet Carré Spillway in 1997. The numerical simulations were validated using the field data collected by the US Geological Survey and US Army Corps of Engineers, as well as satellite imagery obtained from National Oceanic and Atmospheric Administration. The close agreements obtained with technically acceptable accuracy in both field properties and trends of their spatial and temporal variations fully demonstrated this models usefulness in predicting the hydrodynamics, sediment transport, and salinity distribution of lakes under extreme flood forcing. This model provides a useful tool for lake water quality management.

Evaluating the Potential of VI-LST Triangle Model for Quantitative Estimation of Soil Moisture using Optical Imagery

This research evaluates the potential of the vegetation index (VI) - land surface (LST) triangle model for quantitative soil moisture study using Moderate Resolution Imaging Spectroradiometer (MODIS) data in a semi-arid environment. The preliminary results indicate that the VI-LST triangle model has potential to be used for quantitative soil moisture estimation by optical imagery if combined with a reference soil moisture data. The Advanced Microwave Scanning Radiometer-Earth Observing System (AMSR-E) provides quantitative soil moisture estimation at 25 km spatial resolution. AMSR-E soil moisture information can be used in the VI-LST triangle model in conjunction with MODIS reflectance and thermal data to estimate soil moisture at the spatial resolution of MODIS (1 km).

Estimation of Manning's roughness coefficient distribution for hydrodynamic model using remotely sensed land cover features

This research explores the potential of remote sensing techniques to derive distributed Mannings roughness coefficient (Mannings n) for the use in hydrodynamic models for numerical simulation of open channel flow in natural channels and flood plains. Normalized Difference Vegetation Index (NDVI) based land use land cover (LU/LC) data was generated using the Landsat 5 Thematic Mapper (TM) and Advance Land Observing Satellite (ALOS) Panchromatic Remote-sensing Instrument for Stereo Mapping (PRISM) imagery. Mannings n were obtained from published literature for different features in flood plains and correlated with the remote sensing derived LU/LC features. CCHE2D model, developed by the National Center for Computational Hydroscience and Engineering (NCCHE), at The University of Mississippi, for simulating two dimensional depth-averaged unsteady flow and sediment transport was used to validate the remote sensing derived distributed Mannings n for channel flow calculation. Results obtained from this research indicate that satellite imagery derived LU/LC data has potential to be used to improve hydrodynamic model simulation by providing distributed Mannings roughness coefficient for respective model domains.

Toward a Methodology to Investigate the Downstream Flood Hazards on the American River due to Changes in Probable Maximum Flood due to Effects of Artificial Reservoir Size and Land-Use/Land-Cover Patterns

AbstractRecent research in mesoscale hydrology suggests that the size of the reservoirs and the land-use/land-cover (LULC) patterns near them impact the extreme weather [e.g., probable maximum flood (PMF)]. A key question was addressed by W. Yigzaw et al.: How do reservoir size and/or LULC modify extreme flood patterns, specifically PMF via modification of probable maximum precipitation (PMP)? Using the American River watershed (ARW) as a representative example of an impounded watershed with Folsom Dam as the flood control structure, they applied the distributed Variable Infiltration Capacity (VIC) model to simulate the PMF from the atmospheric feedbacks simulated for various LULC scenarios. The current study presents a methodology to extend the impacts of these modified extreme flood patterns on the downstream Sacramento County, California. The research question addressed is, what are the relative effects of downstream flood hazards to population on the American River system under various PMF scenarios f...

Predicting shallow surficial failures in the Mississippi River levee system using airborne hyperspectral imagery

Shallow surficial failures or levee slides in the Mississippi River levee system are very common. There is currently no system to identify or predict the location of these slides before they occur. Studies of slide occurrence mechanisms suggest that probable slide-affected areas are characterized by anomalous vegetation. Compact Airborne Spectrographic Imager II (CASI II) imagery was analysed for selected levee sites in association with slide inventory data and field observations. Normalized Difference Vegetation Index (NDVI), Red edge Vegetation Stress Index (RVSI) and Red Edge Position Index (REP) were calculated from the acquired CASI II imagery. The vegetation indices were used to locate the stressed or anomalous vegetation and predict levee slides. The statistical significance of the predictors was determined by logistic regression. All predictors were found statistically significant for developing a slide prediction model. The slide prediction model was developed by combining the single predictors, categorized vegetation indices, into a model based on all three predictors. Percentage of Search Area Reduction (PSAR) and Failure Index (FI) were used to evaluate the performance of the slide prediction model. Evaluation of the model performance shows that it achieves a maximum FI of 0.43 and PSAR of 99.5.

Visualization of Urban Area Flood Simulation in Realistic 3D Environment

A realistic 3D terrain was generated for part of the areas flooded due to 17th Street, New Orleans levee breaching during Hurricane Katrina by digital image processing techniques and GIS using LIDAR data in conjunction with high resolution multispectral satellite imagery. The DEM was used to generate mesh for simulating flood by CCHE2D Flood models. Propagation of the simulated flood was successfully visualized in realistic 3D environment by image draping technique using high resolution color orthophotographs. Obtained results indicate that (1) high resolution satellite imagery can be very useful to treat LIDAR data for realistic 3D terrain data generation, (2) ortho-rectified high resolution multispectral satellite data or color aerial photographs can be used in conjunction with the treated LIDAR data to generate true color realistic 3D terrain, and (3) propagation of simulated flood generated by CCHE2D Flood models can be visualized in realistic 3D environment using ArcGIS ArcScene software package.

Numerical Modeling of Flow and Sediment Transport in Lake Pontchartrain due to Flood Release from Bonnet Carré Spillway

Lake Pontchartrain is a brackish estuary located in southeastern Louisiana, United States. It is the second-largest saltwater lake in U.S. The lake covers an area of 1630 square km with a mean depth of 4.0 meters. It is an oval-shaped quasi-enclosed water body with the main east-west axis spanning 66 km, while the shorter north–south axis is about 40 km. It is con‐ nected to the Gulf of Mexico via Rigolets strait, to Lake Borgne via Chef Menteur Pass, and to Lake Maurepas via Pass Manchac. These lakes form one of the largest estuaries in the Gulf Coast region. It receives fresh water from a few rivers located on the north and north‐ west of the lake. The estuary drains the Pontchartrain Basin, an area of over 12,000 km2 situ‐ ated on the eastern side of the Mississippi River delta plain.

Application of Advanced Remote Sensing Techniques to Improve Modeling Estuary Water Quality

Estuaries, the interface between terrestrial and coastal waters are an important component of complex and dynamic coastal watersheds. They are usually characterized by abrupt chemical gradients and complex dynamics, which can result in major transformations in the amount, chemical nature and timing of the flux of material along these river–sea transition zones. The ecological functioning of these areas is considered to be of major concern, as estuaries offer the last opportunity to manage water quality problems before they become uncontrollable in the coastal waters.

Flood Inundation and Crop Damage Mapping: A Method for Modeling the Impact on Rural Income and Migration in Humid Deltas

The humid tropics are generally resource-rich lands. They possess adequate water supply, naturally fertile soils, and a favorable terrain. The morphology of these areas ranges from flat lowland delta to river valleys associated with gently rolling uplands. Most of the major deltas in the world (e.g., Ganges, Mississippi, Niger, Okavango, and Mekong deltas) host large population centers, megacities, complex irrigation systems, and a water-sensitive ecosystem because of their easy access to abundant fresh water and fertile soils. Humid deltas of developing nations support extensive agricultural production. Flooding (extreme and normal) is recurrent in these humid deltas. Floods promote as well as hamper agricultural productivity (depending on the magnitude and spatial extent). Therefore, the socioeconomic fabric of the rural areas of humid deltas in developing nations is intricately related to recurrent flooding, agricultural productivity, and crop loss patterns.