Combining high-resolution satellite images and altimetry to estimate the volume of small lakes

This study presents an approach to determining the volume of water in small lakes ( R 2 ABV = 0.98, RMSE ABV = 5%, R 2 HRBV = 0.90, and RMSE ABV = 7.4%), assuming a time-varying triangular shape for the shore slope of the lake (this form is well adapted since it implies a difference inferior to 2% between the theoretical volume of the lake and the one estimated from bathymetry). The third method (AHRBVC) combines altimetry (to measure the lake level) and satellite images (of the lake surface) to estimate the volume changes of the lake and produces the best results ( R 2 AHRBVC = 0.98) of the three methods, demonstrating the potential of future Sentinel and SWOT missions to monitor small lakes and reservoirs for agricultural and irrigation applications.