Fig. 5: Reconstruction of the monthly lake surface area time series based on GSWD annual water classification maps.

Lake Nasser in Egypt in the year 2003 is used as an example to show the reconstruction approach. a The GSWD annual water classification map for 2003. b The reconstructed monthly area for 2003. c The monthly time series of the reconstructed area from Jan 1985 to Dec 2018 obtained after applying the reconstruction approach for each year. The cloud-free water surface area data were collected from the Global Reservoir Surface Area Dataset (GRSAD) and the elevation data were collected from the Global Reservoirs and Lakes Monitor (G-REALM) dataset. Both time series were used as references for comparison with the reconstructed monthly area values.