On the Prospects for Observing Spray-Mediated Air–Sea Transfer in Wind–Water Tunnels

Abstract

ature is wild, unconstrained, and often dangerous. In particular, studying air?sea interaction in winds typical of tropical cyclones can place researchers, their instruments, and even their research platforms in jeopardy. As an alternative, laboratory wind?water tunnels can probe 10-m equivalent winds of hurricane strength under conditions that are well constrained and place no personnel or equipment at risk. Wind?water tunnels, however, cannot simulate all aspects of air?sea interaction in high winds. The authors use here the comprehensive data from the Air?Sea Interaction Salt Water Tank (ASIST) wind?water tunnel at the University of Miami that Jeong, Haus, and Donelan published in this journal to demonstrate how spray-mediated processes are different over the open ocean and in wind tunnels. A key result is that, at all high-wind speeds, the ASIST tunnel was able to quantify the so-called interfacial air?sea enthalpy flux?the flux controlled by molecular processes right at the air?water interface. This flux cannot be measured in high winds over the open ocean because the ubiquitous spray-mediated enthalpy transfer confounds the measurements. The resulting parameterization for this interfacial flux has implications for modeling air?sea heat fluxes from moderate winds to winds of hurricane strength.