Analyzing the performance of the high resolution precipitation products for streamflow simulation

The precipitation products provide an unprecedented opportunity for hydrometeorological applications and climate studies among others. In the present study, five satellite–based precipitation products (TMPA-RT, PERSIANN, CMORPH, TMPA-V6 and PERSIANN-adj) are utilized as forcing data for streamflow simulations over 6-hour and monthly temporal scales for the period of 2003 to 2008. The objective of this study is to evaluate if satellite-based precipitation products are effective to yield good quality streamflow simulations at the basin scale. The conceptual SACramento Soil Moisture Accounting (SAC-SMA) model is employed for streamflow simulation. The results suggest that satellite-based precipitation data can provide valuable input information for hydrologic applications. However, satellite products, with no bias adjustments, significantly overestimate both precipitation inputs and simulated streamflows over warm months (spring and summer months). On the other hand, for colder months, the unadjusted precipitation products result in considerable underestimation of streamflow forecasts. It was found that bias-adjustment of precipitation forcing prior to streamflow simulation is a critical step and can yield to substantial improvement in capturing both streamflow pattern and magnitude.