Evaluation of satellite precipitation products at fine time scale

We evaluate satellite precipitation data at the fine time scale all over the Greek territory. The evaluated satellite data are derived from the algorithm 3B42 Version 6, from the NASA TRMM mission (Tropical Rainfall Measuring Mission). The finest time scale in which this data is evaluated is 3 hours, which is the temporal resolution of the 3B42V6 data. The spatial resolution of the data is 0.25ο. In order to evaluate the satellite data, we used ground observations data from 29 meteorological stations belonging to the National Meteorological Service of Greece (ΕΜΥ). The time period of this evaluation starts in 1/1/1998, since TRMM satellite data is available, and ends in 31/5/2010. After the comparison between satellite and ground data, we extracted the maxima of both data sets by using the empirical distribution and then we compared the respective values. These are 10 and 5 years maxima as the period of the evaluation slightly exceeds a hydrological decade. The durations of the maxima are 3, 6, 12, 24 and 48 hours. Through the maxima comparison, we calculated the bias of the maxima and we tried to depict its spatial distribution on maps using a Geographical Information System (GIS). Moreover, we depicted the spatial distribution of the satellite maxima without any correction. Finally, apart from comparing strictly the maximum values, we checked if the satellite data can simulate the behaviour of maxima (frequency, intensity etc) through the study period (1/1998-5/2010).