The present paper investigates the relationship between the skin sea surface temperature (SSTskin) and the precipitable water (PW) observed over the tropical Indian Ocean. PW is derived from a shipborne Global Positioning System (GPS). Composite diurnal variations indicate that the increase of PW and radar echo coverage (rainfall) in the daytime correspond to the large SSTskin rise during the undisturbed period (The PW increase is statistically significant at 90% level). The surface fluxes calculated using the bulk flux algorithm are too small to account for the observed increase of PW, while the bulk flux agrees with the directly measured eddy flux.
2008 by the Meteorological Society of Japan