Master Thesis.pdf

The change in the lake area was estimated by the NDWI and AWEI indices from data from the Landsat satellite between 1990 and 2019, and this estimate was confirmed in 2019 by points marked along the shoreline of the lake. Thus, the AWEI method was more suitable for our study, so we used the AWEI method in our research.The Khuvsgul Lake is located in a region with a continuous distribution of permafrost and is the region with the ice rich permafrost zone. The area of Khuvsgul Lake has been increasing in recent years, and precipitation around Khuvsgul Lake has not significantly increased since the 1960s. The area of the lake has increased by an average of 1.6 km2 per year over the last three decades. In 2013, it covered the largest area of 2,786.3 km2, while the smallest area in 2000 was 2,780.8 km2. Considering the dependence of air temperature and precipitation on the change in the lake area, the correlation coefficient was less than R=0.29. Glacier and permafrost degradation has intensified in recent years due to global warming. The glacier area of Munkhsaridag mountain is steadily declining, and the major tributaries of Khuvsgul Lake flow from Munkhsaridag mountain. In order to calculate the permafrost effect, the area of the lake was compared to the two permafrost monitoring boreholes near Khuvsgul Lake showed the correlation coefficient greater than R=0.52. Climatic factors, such as air temperature and precipitation, have an indirect effect on Khuvsgul Lake.