The CI-FLOW Project: A System for Total Water Level Prediction from the Summit to the Sea

Kildow et al. (2009) reported that coastal states support 81% of the U.S. population and generate 83 percent [$11.4 trillion (U.S. dollars) in 2007] of U.S. gross domestic product. Population trends show that a majority of coastal communities have transitioned from a seasonal, predominantly weekend, tourist-based economy to a year-round, permanently based, business economy where industry expands along shorelines and the workforce commutes from inland locations. As a result of this transition, costs associated with damage to the civil infrastructure and disruptions to local and regional economies due to coastal flooding events are escalating, pushing requirements for a new generation of flood prediction technologies and hydrologic decision support tools

Development of a Flood Risk Assessment Model For a Braided River System

The aim of this study is to construct a modeling system that will assist flood risk management strategies in a coastal plain braided river system. The model configuration consists of a hydrodynamic model (ADCIRC) of the river basin that receives tidal forcing at the open boundary and river discharge forcing at upstream flux boundary. An unstructured mesh model resolving the Pearl River channels at higher resolution from the coastline to approximately 75km inland to upstream reaches of the river has been constructed. The modeling system produces water levels and currents throughout the Lower Pearl River Basin. Initial sensitivity analysis efforts on the cannel model include consideration of low-flow, average-flow, and high-flow scenarios. Model results were found to be slightly sensitive to slop of river channels and bottom friction to control stability in predictions. The model results were shown to be highly sensitive to the bathymetry fo the model that controls the discharge capacity of the narrow river channels and the channel model resulted in elevated currents and water levels under high flow conditions. A channel discharge capactiy analysis was conducted and the results showed the need to construct a floodplain mesh around the channel model with more realistic bathymetry and topography so that the flooding scenarios could be modeled with wetting and drying capability of ADCIRC. An initial attempt to develop such a floodplain mesh has been made with preliminary results and more comprehensive validation of the developed flood plain modeling system will extend to reproducing events associated witht he historical Hurricane Isaac that impacted the region in 2012. This modelig system will provide an important tool to decision makers that could be used in future flood risk management and mitigation efforts

Development of a Forecast Model for the Lower Pearl River Basin

A numerical model for the Lower Pearl River Basin, a braided river system and its floodplain, is developed for the finite element-based coastal model, ADCIRC. Validation of water level prediction is confirmed for Hurricane Isaac in August, 2012 at five hydrographs (Pearl Riverat Walkiah Bluff near Industrial, MS (WSWM6); Pearl River above Slidell, LA (PRBL1); Pearl River above Slidell, LA (WPSL1) on the West Pearl River; NSTL Station near Stennis, MS (NAPM6); and Pearl River near CSX Railroad near Claiborne (EPCM6) on the East Pearl River)). Results indicate 1) minimal water level error occurs at the river mouth, 2) peak water levels are generally well represented and are within0.5 m of measured flood stage, and 3) prior to the storm, larger errors in simulated water levels along the West Pearl channel likely indicate mismatches between the model and local in situ depth variations. Other useful analyses include a capacity analysis of the braided river channels based on low, average, and high flow conditions from 2014, and a sensitivity analysis of water level and currents to bathymetry, bottom friction coefficient, and land slope representation

A Multi-Scale Model of the Turkish Straits System

Two narrow, shallow straits, the Dardanelles and the Bosphorus, form a physical connection between the Marmara Sea and its adjacent water bodies, the Aegean Sea to the southwest and the Black Sea to the northeast. This collection of seas and straits is known as the Turkish Straits System (TSS). Saline, dense water from the Aegean flows in a deep, lower layer through the Marmara Sea to the Black Sea while fresher, lighter Black Sea water flows in a surface layer to the Aegean Sea. Though the TSS dynamics are the result of interconnections between the interconnected straits and ocean basins, earlier modeling efforts have focused on dynamical studies of individual straits or seas. Often the geometric complexity, broad range of spatial scales present, and computational requirements to represent such disparities have prevented the study of the TSS as a whole. For this study, we utilize state-of-the-art modeling practices to capture the range of spatial scales, geometric complexity, and interconnected dynamics of the TSS. A multi-scale coastal ocean model representing the entire TSS is one-way coupled to a 1 km basin-scale ocean model of the same region. The modeled three-dimensional circulation and density structure of the TSS is examined through a comparison to observations of currents and density taken during the TSS08 sea trial

Evaluation of Wind Field Predictions by Atmospheric Models Over the Marmara Sea

Data collected from meteorological stations in the Turkish Straits System (TSS) around the Marmara Sea are used to assess the performance of atmospheric models in predicting the winds. The Coupled Ocean/Atmosphere Mesoscale Prediction System (COAMPS) is applied using different spatial resolutions ranging between 1 km and 27 km to investigate the effect of model spatial grid resolution on the accuracy of the computed wind field. The influence of ocean dynamics on atmospheric winds also is investigated by comparing wind field predictions from a fully coupled COAMPS with those from an uncoupled (stand-alone atmospheric) COAMPS. Following an examination of the wind products, the importance of using high resolution wind forcing for ocean circulation predictions is evaluated

Modeling the Dardanelles Strait Outflow Plume Using a Coupled Model System

The ADvanced CIRCulation Model, ADCIRC, and the HYbrid Coordinate Ocean Model, HYCOM, are coupled in the Northern Aegean Sea. Over its 62 km, the Dardanelles Strait connects the Aegean Sea to the Marmara Sea. The Dardanelles outflow spreads to the Aegean Sea as a buoyant plume showing seasonal characteristics. The unstructured nature of the ADCIRC mesh provides the resolution necessary to model flow in the narrow strait whose minimum width is about 1 km. During one-way coupling efforts, ADCIRC is initialized using interannual solutions for temperature, salinity, velocity and water surface elevation fields taken from a larger domain HYCOM-AMB model, covering the Aegean, Marmara and Black Seas. Experiments using the one-way coupled model system are targeted at early February and late May of 2003 representing typical winter-spring and summer-fall conditions, respectively

The generation and preservation of multiple hurricane beds in the northern Gulf of Mexico

Cores collected from Mississippi Sound and the inner shelf of the northeast Gulf of Mexico have been examined using 210Pb and 137Cs geochronology, X-radiography, granulometry, and a multi-sensor core logger. The results indicate that widespread event layers were probably produced by an unnamed hurricane in 1947 and by Hurricane Camille in 1969. Physical and biological post-depositional processes have reworked the event layers, producing regional discontinuities and localized truncation, and resulting in an imperfect and biased record of sedimentary processes during the storms. The oceanographic and sedimentological processes that produced these event beds have been simulated using a suite of numerical models: (1) a parametric cyclone wind model; (2) the SWAN third-generation wave model; (3) the ADCIRC 2D finite-element hydrodynamic model; (4) the Princeton Ocean Model; (5) a coupled wave-current bottom boundary layer-sedimentation model; and (6) a model for bed preservation potential as a function of burial rate and bioturbation rate. Simulated cores from the Mississippi Sound region are consistent with the observed stratigraphy and geochronology on both the landward and seaward sides of the barrier islands. © 2004 Elsevier B.V. All rights reserved