Determination of surface area change with remote sensing: The case of Salt Lake

Nowadays, with the advancement of technologies and development of applications, the use of Remote Sensing (RS) techniques is becoming widespread. Thanks to RS, applications such as determination of land surface areas, change analysis, protection of water resources, mapping and sustainable management have begun to be realized. RS and Geographic Information Systems (GIS) provide great advantages and convenience especially in monitoring the temporal changes in the surface areas of water/lake resources. The temporal change of the surface area of a selected water source is observed over months and years. Lakes are important water resources located in terrestrial areas. In this study, it is aimed to determine the surface area change of Salt Lake in the last decade (2014-2023) using RS technique. The determined study area was obtained from Landsat 8 OLI_TIRS satellite images, especially in the summer months (7th and 8th months). Iterative Self-Organized Data Analysis Technique (ISODATA) was preferred as the method for unsupervised classification. Due to the low cloudiness, the images were generally obtained in August. From these images, vegetation/water area was analyzed using NDVI (Normalized Difference Vegetation Index) and NDWI (Normalized Difference Water Index) and drought and wetlands in the region were monitored. According to the NDVI results, the highest value was determined as 0.73 in 2022 and the lowest value was determined as 0.59 in 2017. For the NDWI index in 2022, these values were calculated as 0.66 and -0.98, respectively. The average surface area of the Salt Lake in the last decade was found to be 999,464 km², and the changes between the years were compared with each other.