Modeling Waves and Currents Produced by Hurricanes Katrina, Rita, and Wilma

摘要

The 2005 Atlantic hurricane season, with three Category-5 hurricanes within a time span of two months (Katrina, Rita and Wilma, August to October) in the Caribbean Sea and the Gulf of Mexico, underscored an important fact: as populations boom in coastal regions and as the earth embraces a warmer climate with higher sea-surface temperatures (SST) over the tropical oceans, the next decade may see increasingly more intense storms that pose greater risks than ever before (Emanuel, 2005a). In particular, the strong currents and waves produced by Hurricanes Katrina (August 23-30, 2005) and Rita (September 18-26) caused considerable human sufferings and property losses, as well as damage to gas and oil facilities in the northern Gulf of Mexico continental shelf and slope. The Minerals Management Service (MMS) wishes to assess the impacts of these waves and currents, hence our research. Assessments of wave and current responses to intense hurricanes are important especially in view of forecast threats of increasingly more powerful storms due to the warming climate. We have conducted such an assessment study using a combination of numerical modeling and observational data analyses. The goal is to provide the MMS with our best estimates of the strengths as well as spatial and temporal distributions of currents and waves during Katrina and Rita in the northern Gulf of Mexico. It was further suggested during the Kick-Off-Meeting that a study of the effects of Hurricane Wilma could provide additional insights, and this too has been conducted. In addition to providing practical assessments, we also focus on basic understanding of the physics of the ocean response to these intense hurricanes, and to a more limited extent, the physics of air-sea interaction as well.