River discharge is an important quantity of the hydrologic cycle because it is essential for both scientific and operational
applications related to water resources management and flood risk prevention. Streamflow measurements are sparse and
for few sites along natural channels and, hence, they are not able to detect adequately the complexity of variation in
surface water systems. Therefore, in recent years, the possibility to obtain river discharge estimates through remote
sensing monitoring has received a great interest. In this context, the capability of the MODerate resolution Imaging
Spectroradiometer (MODIS) for river discharge estimation is investigated here. Thanks to a very short revisiting time
interval and a moderate spatial resolution (up to 250 m), MODIS has a significant potential for mapping flooded area
extent and flow dynamics. Specifically, for the estimation of river discharge, the ratio of the MODIS channel 2
reflectance values between two pixels located within and outside the river is used. Time series of daily discharge
between 2006 and 2010 measured at two gauging stations located along the Upper Tiber River basin (central Italy) are
employed to test the procedure. The agreement between MODIS-derived and in situ discharge time series is found to be
fairly good with correlation coefficient values close to 0.8.
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