 This study used satellite imagery from Landsat-5TM, 7-ETM+, and 8-OLI to model spatiotemporal changes of Lake Urmia in the period 2000 to 2013. The normalized difference water index, NDWI, was found superior for surface water extraction and a new approach based on principal components of multi-temporal NDWI, NDWI-PCS, was proposed and evaluated for surface water change detection. Results indicate an intense decreasing trend in Lake Urmia's surface area between 2010 and 2013, with the NDWI-PCS approach effectively detecting changes between two and three different times simultaneously. This article was authored by Comyle Rockney, Annua Maud, Ali Selamat, and others.