BULK PARAMETERIZATION OF AIR-SEA FLUXES FOR TROPICAL OCEAN GLOBAL ATMOSPHERE COUPLED OCEAN-ATMOSPHERE RESPONSE EXPERIMENT

This paper describes the various physical processes relating near-surf ace atmospheric and oceanographic bulk variables; their relationship t o the surface fluxes of momentum, sensible heat, and latent heat; and their expression in a bulk flux algorithm. The algorithm follows the s tandard Monin-Obukhov similarity approach for near-surface meteorologi cal measurements but includes separate models for the ocean's cool ski n and the diurnal warm layer, which are used to derive true skin tempe rature from the bulk temperature measured at some depth near the surfa ce. The basic structure is an outgrowth of the Liu-Katsaros-Businger [ Liu et at, 1979] method, with modifications to include a different spe cification of the roughness/stress relationship, a gustiness velocity to account for the additional flux induced by boundary layer scale var iability, and profile functions obeying the convective limit. Addition ally, we have considered the contributions of the sensible heat carrie d by precipitation and the requirement that the net dry mass flux be z ero (the so-called Webb correction [Webb et at, 1980]). The algorithm has been tuned to fit measurements made on the R/V Moana Wave in the t hree different cruise legs made during the Coupled Ocean-Atmosphere Re sponse Experiment. These measurements yielded 1622 fifty-min averages of fluxes and bulk variables in the wind speed range from 0.5 to 10 m s(-1). The analysis gives statistically reliable values for the Charno ck [1955] constant (beta = 0.011) and the gustiness parameter (beta = 1.25). An overall mean value for the latent heat flux, neutral bulk-tr ansfer coefficient was 1.11 x 10(-3), declining slightly with increasi ng wind speed. Mean values for the sensible and latent heat fluxes wer e 9.1 and 103.5 W m(-2); mean values for the Webb and rain heat fluxes were 2.5 and 4.5 W m(-2). Accounting for all factors, the net surface heat transfer to the ocean was 17.9 +/- 10 W m(-2).