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Land Area Change and Overview of Major Hurricane Impacts in Coastal Louisiana, 2004-08

John A. Barras
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Abstract

The U.S. Geological Survey (USGS) assessed changes in land and water coverage in coastal Louisiana within 2 months of Hurricane Gustav (September 1, 2008) and Hurricane Ike (September 13, 2008) by using Landsat Thematic Mapper (TM) satellite imagery. The purpose of this study was twofold: (1) to provide preliminary information on land-water area changes in coastal Louisiana shortly after Hurricanes Ike and Gustav made landfall and (2) to contrast these changes with prior, widespread land area changes caused by Hurricane Katrina (August 29, 2005) and Hurricane Rita (September 24, 2005) 3 years earlier. Hurricane Gustav's physical surge impacts were not as severe as those observed from Hurricane Katrina. The largest observed changes were the reversion of recovery vegetation in Upper Breton Sound to an immediate post-Katrina appearance. Hurricane Ike's surge impacts were similar, although of somewhat lesser magnitude than Hurricane Rita's surge impacts. Major surge-removed marsh occurred in similar locations with similar morphologies from the two westward tracking storms. Although the net reduction in land from 2004 to 2008 (849.5 km2) exceeded that from 1978 to 2004 (743.3 km2), it is likely that the 2004-08 estimate will decrease, given time for the coast to recover from those hurricane seasons. Nevertheless, it is likely that the cumulative loss from these hurricane seasons will remain significant. Estimation of permanent losses cannot be made until several growing seasons have passed and the transitory impacts of the hurricanes are accounted for.

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John A. Barras. 2009. Land Area Change and Overview of Major Hurricane Impacts in Coastal Louisiana, 2004-08. https://doi.org/10.3133/sim3080

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