Verification of reconstructed total precipitation from GPM IMERG data in the south of Western Siberia

This paper presents the results of verification of reconstructed precipitation totals based on GPM IMERG satellite measurements with standard observations at hydrometeorological stations in the south of Western Siberia. Two products - "HQprecipitation" and "precipitationCal" - were considered in the "GPM_3IMERGDF" dataset. The former represents precipitation intensity information reconstructed from microwave channel data only, the latter from microwave and longwave channel data. The average unconformity of both GPM IMERG datasets is 3.7 mm, with median values of 1.9 and 2.0 mm for the "HQprecipitation" and "precipitationCal" datasets, respectively. It was also found that for extreme precipitation events the uncertainty for both products increases significantly. For coordinates of mountainous meteorological stations, a predominant underestimation of both products is observed. Comparison of GPM IMERG data in different seasons showed that both products are 2 times more accurate in winter than in summer. The results show that in general both GPM IMERG products have acceptable accuracy for all precipitation events.

Acknowledgements: This study was supported by the Ministry of Science and Higher Education of the Russian Federation, grant No. 121031300154-1.