Surface wave processes in high winds and hurricanes

During the 2002-2004 Atlantic Hurricane seasons we participated in the ONR-sponsored Coupled Boundary-layer Air-Sea Transfer (CBLAST) experiment flying video imaging equipment on the NOAA P3 aircraft to study wave breaking and sea-surface foam in hurricanes. In February 2004 we undertook the Gulf of Tehuantepec Experiment (GOTEX) off the Pacific coast of Mexico, flying the NASA airborne terrain mapper (ATM) for surface wave measurements and imaging equipment to study the coupled development of the atmospheric boundary layer and the surface waves in high winds. The two studies are complementary and together were designed to better understand the role of surface wave breaking in high winds and hurricanes. The role of wave breaking in the momentum and energy fluxes between the atmosphere and the ocean may prove significant in the dynamics and thermodynamics of air-sea interaction in high winds. While surface wave processes in hurricanes are complicated by the effects of turning winds, the “Tehuano” winds in the Gulf of Tehuantepec are characterized by the fact that they blow consistently offshore for several days on an almost weekly cycle during winter, and may reach hurricane force at times. In this talk we present a summary of the measurements of the evolution of the surface wave fields in GOTEX, especially the incidence of breaking, the occurrence of extreme or “rogue” waves, and the implications for surface wave processes and their modeling in hurricanes.