A method for determining the diurnal sea surface temperature (SST) cycle through satellite data has previously been developed by Clayson and Curry (1996). The maximum amplitude of the diurnal cycle in this method is determined using magnitude of peak solar insolation, the cumulative amount of daily precipitation, and average daily wind speed. This method has been applied to data obtained by the International Satellite Cloud Climatology Project (ISCCP) and Special Sensor Microwave/Imager (SSM/I) data to produce a daily diurnal variation in SST database for the global tropics during the years 1996-2000. The resolution of the data is 0.25 degrees x 0.25 degrees. This database represents a new way of studying variability of the upper ocean over many spatial and temporal scales. This study will explore the variation of maximum amplitude of the diurnal cycle across the global tropics for the years mentioned, and comparisons will be made year to year on how this variability changes climatologically. Certain regions will be focused upon such as the tropical Pacific for ENSO effects, and the western Pacific and Indian Ocean for monsoon variability.