The use of H-SAF soil moisture products for operational hydrology: flood modelling over Italy

The ever increasing availability of new remote sensing and land surface model datasets opens new chances for hydrologists in improving flood forecasting systems. The current study investigates the performance of two operational soil moisture (SM) products provided by "EUMETSAT Satellite Application Facility on Support to Operational Hydrology and Water Management" (H-SAF, http://hsaf.meteoam.it/) within a recently developed hydrological model called "Simplified Continuous Rainfall-Runoff Model" (SCRRM) and the possibility to use such a model at an operational level. The model uses SM datasets derived from external sources (i.e. remote sensing and land surface models) as input for calculating the initial wetness conditions of the catchment prior to the flood event. Hydro-meteorological data from 35 Italian catchments ranging from 800 to 7400 km2 was used for the analysis for a total of 593 flood events. The results show that H-SAF operational products used within SCRRM satisfactorily reproduces the selected flood events providing a median Nash-Sutcliffe efficiency index equal to 0.64 (SM-OBS-1) and 0.60 (SM-DAS-2), respectively. Given the results obtained along with the parsimony, the simplicity and independence of the model from continuously recorded rainfall and evapotranspiration data, the study suggests that i) SM-OBS-1 and SM-DAS-2 contain useful information for flood modelling which can be exploited in flood forecasting, ii) SCRRM is expected to be beneficial as a component of a real-time flood forecasting systems in regions characterized by low data availability where a continuous modelling approach can be problematic.