Chou et al. (1998) produced daily mean surface net shortwave and longwave radiative fluxes for the western Pacific warm pool (from the Japan GMS data) for the COARE IOP (intensive observing period). In addition, daily mean air-sea turbulent fluxes have been produced from the SSM/I data using the method of Chou et al. (1997). In this paper, we focus on three areas. The first area is to further assess accuracy of the retrieved daily mean surface fluxes using those from the IMET buoy, RV Moana Wave, and RV Wecoma. The second area is to describe the temporal and spatial variability of the surface heat budget (as well as the related parameters) over the warm pool during the IOP. The third area is to discuss the relation of SST (sea surface temperature) change to surface fluxes, including the transmission of solar flux through the ocean mix-layer.
For three legs observed during the COARE IOP, the retrieved surface fluxes compare reasonably well with those from the IMET buoy, Moana Wave, and Wecoma. The spatial and temporal variability of net solar flux over the warm pool during the IOP is consistent with that of the GMS IR brightness temperature, as both are dominated by clouds. In addition, the spatial and temporal variability of latent heat flux is consistent with that of wind stress, indicating that the evaporative cooling is mainly driven by the wind speed. Over the southern warm pool, the time series of SST is modulated by two MJOs (Madden Julian oscillations). This is because the surface net heat flux is dominated by solar flux, which is modulated by the two MJOs. On the other hand, over the northern warm pool, the time series of SST is dominated by the seasonal change. This is because the surface net heat flux is dominated by latent heat flux, which is modulated by the strengthen of the NE trade winds. Averaged over the IOP, the surface net heating over the central warm pool is found to be positive and to reach 60 W m-2. However, the SST cools at a rate reaching 0.3 oC month-1. This is because part of solar flux penetrates through the bottom of the mixed-layer and is not available to heat the ocean mixed-layer. Our analyses suggest that the wind stress is a major factor for determining the mixed-layer depth in the warm pool