Edward Silberman Award Ceremony and Seminar
Silberman Award Recipient: Maria Garcia-Serrana, PhD Candidate in Civil, Environmental, and Geo- Engineering
Distinguished Lecturer: Fabrice Veron, Director, Physical Ocean Science and Engineering and Professor, School of Marine Science and Policy, University of Delaware
The exchanges the atmosphere and the oceans are crucial in driving weather and controlling global climate trends. These exchanges are largely influenced by the small-scale dynamics at the surface of the ocean. Surface waves are known to influence the air-sea fluxes but the details are still poorly understood. We present laboratory measurements of the airflow above a wavy air-water surface for different wind and wave conditions. Laboratory data were obtained at University of Delaware’s (42-m long) wind-wave-current facility, using a multi-camera multi-laser setup that combines PIV with laser induced fluorescence. We observe coherent turbulent structures in the airflow, including ejections of low velocity fluid away from the surface and downward sweeps of higher velocity fluid. Wave-phase-resolved quadrant analysis suggests that these events are modulated by the waves. Airflow separation occurs past young wave crests (Cp/U < 3.7), producing intense phase-locked turbulence. When Cp/U= 6.5, the mean wave-coherent airflow is qualitatively consistent with linear critical layer theory.