Bulk Formulation of the Heat and Water Vapor Fluxes at the Air–Sea Interface, Including Nonmolecular Contributions

Abstract

Accurate prediction of the air?sea sensible and latent heat fluxes is vital for nearly all applications of atmosphere and ocean models. Existing theories of heat transfer over rough surfaces provide a starting point, but they seem incomplete given that recent measurements suggest a departure from these theoretically predicted fluxes at higher wind speeds. Although explicit models of the air?sea heat fluxes are desperately needed, the formulation presented in this paper is an attempt to model the air?sea fluxes without dependence on explicit heat flux components. Using smooth flow limit approximations, theoretical profiles, and a physically based surface stress model, the predicted heat fluxes show reasonable agreement with available data. With increasing wind forcing, modestly increasing heat and moisture exchange coefficients (Stanton and Dalton numbers) are found. Even though wave age strongly influences the surface drag, stratification and temperature effects seem to dominate the wave-age influence on the air?sea heat and moisture fluxes.