Abstract:
Hourly precipitation observation data from 70 meteorological stations are used to evaluate the satellite retrieval products of Tropical Rainfall Measuring Mission (TRMM) 3B42RT during May to October from 2000 to 2013 in Zhejiang province. It has been specially assessed for rainfall of typhoons. The results show that the satellite precipitation data is similar to ground rain gauge data in revealing the precipitation amounts for four time-scales, i.e., 3 h, 6 h, 12 h and 24 h. The TRMM 3B42RT data are significantly correlated with rain gauge data. The correlation coefficients increase with the increasing timescale, and the larger values locate in western Zhejiang. In both the periods from May to October and during typhoon, diurnal variations of rainfall characterized by TRMM 3B42RT show a good agreement with rain gauge data. The 3B42RT can also reflect correctly the peak of rainfall. The 3B42RT products underestimate the typhoon rainfall in Zhejiang Province. But the correlation between TRMM 3B42RT and rain gauge data during typhoon is much better than that during the whole period from May to October, and the larger correlation coefficients locate in eastern coastal areas of Zhejiang during typhoon. The 3h accumulated precipitation difference sequence computed by 3B42RT is significantly and positively correlated with that by rain gauge data. So, the evolutions of the rainfall change over time obtained by the two data are consistent. Results of correlation analyses and MODE method indicate that 3B42RT correctly shows the structure of the main rain belts during Typhoon Rananim (0414).