Interrelationship between Sea Surface Temperature and Clouds over the Tropical Ocean

The intra-annual and interannual variations of total, high, middle, low clouds, and cloud forcing net solar radiation flux, cloud forcing net long-wave radiation flux, and SST over the tropical oceans are investigated with the use of International Satellite Cloud Climatology Project(ISCCP) D2, National Centers for Environmental Prediction/National Center for Atmospheric Research(NCEP/NCAR) reanalysis data for January 1983-December 1993. The intra-annual variation of total cloud amount(TCA) is dominated by high and middle clouds in the western Pacific and central tropical oceans, the interannual variation of TCA is also dominated by high and middle clouds in the central Pacific and Atlantic. The dominant intra-annual and interannual empirical orthogonal functions(EOFs) of TCA have spatially coherent link with those of sea surface temperature(SST). For the interannual EOFs, TCA and SST are related to El $Nin{\~{o}}-Southern$ Oscillation(ENSO). The second most important intra-annual EOFs of TCA are related to inter tropical convergence zone(ITCZ). The third most important intra-annual EOFs show coherent relation in the western Pacific. The correlation analysis between cloud radiative effects and SST show spatially coherent relation over the tropical oceans even though cloud forcing cooling effect is much higher than heating effect on the surface.