INVESTIGATION OF LAKE CHANGES IN THE AFAR DEPRESSION OF ETHIOPIA USING REMOTE SENSING AND GIS

The Afar Depression of Ethiopia is a plate tectonic triple junction and is a main part of the Eastern African Rift System. Surface water reservoirs in the Afar Depression play an important role as a water resource and as an economic potential in Ethiopia. Salt mining, fishing, and recreation are the major practices in eight inland water bodies. Ethiopia is prone to tectonic, magmatic, and drought hazards due to its geologic setting and geographic location. This study incorporates remote sensing and Geographic Information Systems (GIS) to investigate fluctuations in the surface area of eight lakes in Afar between 1990 and 2016. About 158 scenes of Landsat 5, 7, and 8 are used in this study. All images are geometrically and radiometrically corrected, and then a GIS density slice technique is applied to reclassify Band 4 (the near infrared band) of all Landsat images and to assess changes in the surface water reservoirs. A time series of Landsat observations has been created to monitor the spatial and the temporal variations in each lake during the study period. Ultimately, the relationship between lake area fluctuations (expansion and shrinkage) and seismic, magmatic, and climatic records has been established and examined. Patterns and rates of change indicate that lakes in Afar are influenced notably by climatic factors.