A Global Error Model for Satellite Precipitation Products

The PUSH (Precipitation Uncertainties for Satellite Hydrology) error scheme is presented to provide global estimates of errors for high time resolution, merged precipitation products. Each of the following four scenarios is explored and explicitly modeled: correct no-precipitation detection (both satellite and gauges detect no precipitation), missed precipitation (satellite records a zero, but it is incorrect), false alarm (satellite detects precipitation, but the reference is zero), and hit (both satellite and gauges detect precipitation). Previous studies have shown that PUSH was able to reproduce the probability density functions of the benchmark precipitation, to capture missed precipitation and false detection uncertainties, and to reproduce the spatial pattern of the error over the Oklahoma region. This study shows how this framework can be generalized to other regions of the world, based on information that is available anywhere anytime. This will be exceptionally crucial in un-gauged regions of the world, where satellite retrievals represent the only available precipitation estimate on which hydrological applications (e.g., flood forecasting) and water resources management can rely. A methodology to discern the systematic and random components of the error is also investigated.