Climatic variables impact on inland lakes water levels and area fluctuations in an arid/semi-arid region of Iran, Iraq, and Turkey based on the remote sensing data

In this study, the impact of vegetation, land surface temperature, and precipitation on changes in water level and area of seven inland lakes (Urmia lake in Iran, Tharthar, Mosul lakes and Hammar 4 wetland in Iraq, and Beyşehir and Erçek lakes in Turkey) is analyzed to evaluate the variability of these lakes due to climate change. The altimetric data from four remote sensing databases (TOPEX/POSEIDON and Jason 1, 2, and 3), the area of the lakes from the images of Landsat OLI and ETM + sensors, the vegetation from MOD13Q1-NDVI 250 m database, land surface temperature from LST-MOD11A1, and precipitation from GPM_3IMERGM product were used in this study to assess the changes occurring in the period of the last 20 years (2000–2019). The results showed that in the analyzed area the values of the land surface temperature and vegetation indices increased, whereas annual precipitation sums decreased. Although temperature and vegetation changes in all three countries were almost consistent with each other, changes in the water level and area of the studied lakes were different. The highest decrease in the water level was observed for Urmia lake. Although decreases in the water level were also observed in other lakes, their water level returned after a time to its initial level (1992). This was not the case for Urmia lake, where the water level after 1999 never returned to the initial value, finally lowering by 7 m. The fluctuations of the water level and area of Iran, Turkey, and Iraq lakes are however caused by factors other than only those related to climate, which needs more investigations to determine more precisely the changes in the water level of these lakes.