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Hurricane Katrina (August 23–30, 2005) was one of the costliest and deadliest hurricanes to ever strike the United States, impacting low-lying coastal plains particularly vulnerable to storm surge flooding. Maximum storm surges, overland flow depths, and inundation distances were measured along the Gulf Coast of Florida, Alabama, Mississippi, and Louisiana. The vehicle-based survey was complemented by inspections with the reconnaissance boat along the Gulf Coast and the Mississippi Barrier Islands. The survey covered both the impact on the built and the natural environments. The storm surge peaked to the east of Katrina’s path exceeding 10 m in several locations along the Mississippi coastline. The storm surge measurements show that the lower floors of specially designed buildings were damaged by the surge of seawater and associated wave action, while the upper floors sustained minimal wind damage. The storm surge measurements along New Orleans Lakeshore allowed the investigators to exclude overtopping as failure mechanism for the 17th Street outfall canal levee. Hurricane Katrina’s storm surge distribution (Category 3 at landfall) is compared against Hurricane Camille’s storm surge distribution (Category 5 at landfall). The land loss on the barrier islands and the increased vulnerability of the US Gulf Coast to future hurricane storm surges is discussed. [ABSTRACT FROM AUTHOR]

Abstract: Hurricane Katrina (23–30 August 2005) struck low-lying coastal plains particularly vulnerable to storm surge flooding. Maximum storm surges, overland flow depths, and inundation distances were measured along the Gulf Coast of Florida, Alabama, Mississippi and Louisiana. The vehicle based survey was complemented by inspections with the reconnaissance boat along the Gulf Coast and the Mississippi Barrier Islands. The storm surge peaked to the East of Katrina’s path exceeding 10meters in several locations along the Mississippi coastline. The storm surge measurements show that the lower floors of specially designed buildings were damaged by the surge of seawater and associated wave action, while the upper floors sustained minimal wind damage. Furthermore, the storm surge measurements along New Orleans’s Lake shore indicate that the 17th Street Canal levee failed prior to overtopping. The land loss on the barrier islands resulted in an increased vulnerability of the US Gulf Coast to future hurricane storm surges. [Copyright &y& Elsevier]

Ocean currents represent an alternative source of clean energy given their inherent reliability, persistence and sustainability. The general ocean circulation is characterized by large rotating ocean gyres resulting in rapid ocean currents along the western boundaries because of the Coriolis Effect. The Gulf Stream system is formed by the western boundary current of the North Atlantic Ocean flowing along the east coast of the United States, and is of particular interest as a potential energy resource for the United States. This study presents a national database of ocean current kinetic energy resource derived from seven years of numerical model simulations to help advance awareness and market penetration for ocean current energy. A web based GIS interface is provided for dissemination of the national energy resource data: http://www.oceancurrentpower.gatech.edu/ . The website includes GIS layers of computed monthly and yearly mean ocean current speed and associated power density along the coastlines of the United States, as well as joint and marginal probability histograms for current velocities at a variable horizontal resolution of 4–7 km. Various tools are provided for viewing, identifying, filtering and downloading the data from this website. The Gulf Stream system, especially the Florida Current, concentrates the highest kinetic power density ( > 2000 W / m 2 ). The majority of the kinetic power and its variability are only present in relatively shallow water given the strong correlation with the surface wind stress. The kinetic energy flux in the Florida Current is estimated over 30 years to provide temporal variability of the undisturbed kinetic energy with high statistical significance. Available power of approximately 5 GW associated with the undisturbed natural flow condition from the Gulf Stream system is predicted based on hypothetical turbine parameters. Successful development of renewable energy generation requires further studies to account for more precise technical, economic and environmental constraints. [ABSTRACT FROM AUTHOR]

Abstract: A geodatabase of tidal constituents is developed to present the regional assessment of tidal stream power resource in the USA. Tidal currents are numerically modeled with the Regional Ocean Modeling System (ROMS) and calibrated with the available measurements of tidal current speeds and water level surfaces. The performance of the numerical model in predicting the tidal currents and water levels is assessed by an independent validation. The geodatabase is published on a public domain via a spatial database engine with interactive tools to select, query and download the data. Regions with the maximum average kinetic power density exceeding 500W/m2 (corresponding to a current speed of ∼1m/s), total surface area larger than 0.5km2 and depth greater than 5m are defined as hotspots and documented. The regional assessment indicates that the state of Alaska (AK) has the largest number of locations with considerably high kinetic power density, followed by, Maine (ME), Washington (WA), Oregon (OR), California (CA), New Hampshire (NH), Massachusetts (MA), New York (NY), New Jersey (NJ), North and South Carolina (NC, SC), Georgia (GA), and Florida (FL). [Copyright &y& Elsevier]

Abstract: A multi-criteria assessment methodology that accounts for the physical, environmental and socioeconomic constraints is proposed to assist in the selection of the most suitable locations for tidal stream power conversion projects. For this purpose, the tidal stream power resource data are incorporated into a Geographical Information System (GIS) database together with datasets that are related to different aspects of the site selection methodology. The proposed method is applied to the Georgia coast to find and rank the best locations for power conversion. The suitable areas are narrowed down to a subset of the high power density areas that satisfy the constraints of a tidal stream power conversion scheme. A demonstrative ranking procedure with equal weighting factors for all criteria shows that the Savannah, Ogeeche, Canoochee and Medway Rivers and the Cumberland Sound have the best locations for tidal power conversion on the coast of Georgia. This methodology is also applicable to other sites where sufficient geospatial data are available. [Copyright &y& Elsevier]

Abstract: The wave power potential along the southeast Atlantic coast of the United States of America bounded by latitudes 27° N and 38° N and longitudes 82° W and 72° W (i.e. North Carolina, South Carolina, Georgia, and northern Florida) is investigated. The available data from National Data Buoy Center wave stations in the given area are examined. Temporal trends of the wave heights, wave periods and the wave power are analyzed for a time scale of weeks. The time series from the wave stations are downsampled with a 15-day moving average filter with near 50% overlapping to study the seasonal trends. Power calculated from hourly significant wave heights and average wave periods is compared to power calculated using spectral wave density. It is found that a factor of 0.61 needs to be applied to the wave power calculated from hourly significant wave heights and average periods in order to get the same results with the power calculated from spectral wave density. The mean power within 50km of the shore is determined to be ∼9kW/m, whereas higher power (∼15kW/m) is available further offshore. [Copyright &y& Elsevier]