Using gauge and radar data from TRMM ground validation sites to determine the diurnal rainfall cycles of quarter degree pixels, seasonal rain rate, and seasonal rain coverage
Analysis of Melbourne reveals the time of maxium rainfall is earliest near the coast and the percentage of areal coverage during Winter has a bimodal cycle. Analyzing Houston we find the time of maxium rainfall to be earlier to the southeast and mean rainfall to be highest to the south. Percentage of areal coverage during the Fall at Houston reveals a morning maximum, which we suggest is due to the influence of nocturnal mesoscale convective systems generated over the hill country. Analysis of Darwin shows maxium, minium, and mean rainfall to be higher along the coast and percentage of areal coverage during the wet season has three modes. Analyzing Kwajalein we find maximum and minium rainfall are slightly higher to the north and percentage of areal coverage during Sep-Oct-Nov reveal a large nocturnal maximum. The meteorological factors that cause these observations will be discussed.
The availablity of high resolution high quality radar and gauge data has given us the ability to analyze the diurnal cycle of rainfall on a small scale and seasonally. Our observations provide crucial data for instantaneous and climatological validation of satellite retrievals and will prove essential to the improvement of physically-based satellite retrievals.