A Parameterization Scheme for Air–Sea Surface Interface Fluxes: Design and Stand-Alone Experiments

Abstract

AbstractObservations show that sea surface temperature (SST) can vary up to several degrees in a day and sea surface energy fluxes up to a few hundreds of watts per square meter. For synoptic- and subsynoptic-scale atmospheric modeling, there remains a need for the parameterization of air?sea surface interaction using simple schemes. In this paper, such a simple scheme, Atmosphere?Ocean Surface Interaction Scheme (AOSIS), is presented so that the short time variations in SST and energy fluxes can be estimated using a small number of atmospheric and oceanic bulk quantities. The scheme consists of three components: a two-layer ocean temperature model, a wind-wave model, and a surface flux model. Numerical experiments show that the scheme performs well in simulating SST and the air?sea exchanges. Relative to other schemes, AOSIS shows the following improvements: 1) it simulates SST and the cool-skin and warm-layer effect of the ocean mixed layer without the input of ocean bulk temperature of the mixed layer as a prior condition, which is required by most one-layer models; 2) the depth of the ocean mixed layer is allowed to vary according to surface wind stress and buoyancy flux; and 3) a method for computing ocean surface roughness length is proposed, which accounts for the aerodynamic effect of wind-generated waves. For experimental studies, AOSIS can be used in stand-alone mode for the calculation of SST through a small number of bulk measurements. AOSIS can also be used as an interface between the atmosphere and ocean models to be coupled together.