How reliable are satellite precipitation estimates for driving hydrological models: A verification study over the Mediterranean area

The objective of this study is to explore the feasibility of using SRPs to force a lumped hydrologic model - MISDc - over 15 basins in the Mediterranean area with different sizes and physiographic characteristics. Specifically, TMPA 3B42-RT, CMORPH, PERSIANN and a new soil moisture-derived rainfall datasets, SM2RAIN(CCI), obtained through the application of SM2RAIN algorithm (Brocca et al., 2014) to ESA CCI soil moisture product are used in the analysis. The performances obtained with the selected SRPs are compared with those obtained from a ground-based rainfall product (E-OBS). In addition, the performance obtained by an integration of the SRPs is investigated to see whether merged rainfall observations are able to improve flood simulations.

Satellite-based rainfall products (SRPs) are nowadays available at ever increasing accuracy and higher spatial and temporal resolution with respect to the past. Despite this, they are scarcely used in hydrological modeling. The main reasons may be related to: 1) the large bias characterizing satellite precipitation estimates, which is dependent on rainfall intensity and the season, 2) the relatively large spatial/temporal resolution with respect to the applications, 3) the timeliness, which is often insufficient for operational purposes, and 4) a general (often not justified) skepticism of the hydrological community in the use of satellite products for land applications.