On the uncertainties in validating satellite instantaneous rainfall estimates with raingauge operational network

Results show that a careful selection of the raingauge network density, time sampling, and raingauge interpolation algorithms can greatly reduce such matching errors that, however, can be very high. A Fractional Standard Error ranging from 100% to 300% between satellite estimate and raingauge reference value can be due to different raingauge sampling and interpolation strategy, while a reduction in the raingauge density of a factor of 2 leads to a degradation of the quality of the interpolation of about 40%.