Storm Surge Return Periods for the United States Gulf Coast

Abstract

This study estimates tropical cyclone-generated storm surge levels for 2-year, 5-year, 10-year, 25-year, 50-year and 100-year return periods along the U.S. Gulf Coast. The study utilizes SURGEDAT, a Gulf of Mexico storm surge database, for statistical analysis. The most recent 111 years (1900-2010) of this 131-year dataset are analyzed, as this time period maximizes surge observations, while minimizing missing data. Return periods are calculated using the Pareto, Gumbel and Beta-P distributions, and the Huff-Angel and Southern Regional Climate Center (SRCC) linear regression methods. The Kolmogorov-Smirnov Statistic indicates that the SRCC method produced the best results. The SRCC method estimated basin-wide surge levels ranging from 2.67 meters for the 2-year return period to 8.20 meters for the 100-year return period. A K-means clustering algorithm was employed to separate Gulf Coast surges into 10 separate sub-regions. Surge levels for the 10-year, 25-year, 50-year and 100-year return periods were calculated for each sub-region using the SRCC linear regression method. The Southeast Louisiana/ Mississippi Zone generated the highest surge levels for each return period. Surge levels in this zone ranged from 2.72 meters for the 10-year return period, to 7.67 meters for the 100-year return period. These high surge levels are obviously driven by the extreme surges associated with Hurricanes Katrina and Camille. The lowest surge levels in the region were estimated along the West Coast of Florida. These results are useful for emergency management and disaster science personnel, planners, decision makers, stakeholders in various industries, as well as the scientific research community.