By Sid Perkins
When Hurricane Ike struck the Gulf Coast in the early hours of September 13, 2008, Texas’ Bolivar Peninsula was ground zero. Before the category 2 storm made landfall, large stretches of beachfront on this narrow, low-lying spit of land were chockablock with homes standing on stilts behind dunes up to 2 meters tall.
But those stilts — and the dunes — were too short: Most of the homes that didn’t get blown away by Ike’s 175-kilometer-per-hour winds were battered by waves and then swept off pilings by a 5-meter-deep, debris-filled storm surge. Terrain was swept clean, and dunes were decapitated. Across some stretches of shore, the ocean chewed inland more than 50 meters, while other sections of beach actually gained ground as storm water draining from marshes and bays carried sediment toward the sea, dropping the material at the water’s edge.
Such resculpting of shorelines by storms has become a popular research topic lately, thanks to the availability of high-tech data collection equipment ranging from sonar-equipped ships to GPS-carrying all-terrain vehicles and small aircraft with laser altimeters. As few as a dozen years ago, field studies assessing storm-induced shoreline changes required an army of surveyors and hordes of graduate students, says Asbury “Abby” Sallenger, head of the U.S. Geological Survey’s storm impacts research group in St. Petersburg, Fla.