2020 年 76 巻 5 号 p. I_301-I_309
Water resources are dramatically sensitive to climate change in Mongolia. In this study, the authors aimed to evaluate the impact of climate change on Ogii Lake by using the estimated daily evaporation from the lake and the variation in the surface area of the lake. Ogii Lake is located in the eastern region of Arkhangai Province, central Mongolia, which registered as an International Ramsar Convention site in 1998. Evaporation was estimated from 1986–2019 using the energy-budget method based on ERA5 reanalysis climate data. Landsat–8 operational land imager (OLI) satellite remote sensing images were used to estimate the monthly lake water surface area changes from 2013–2019. The results showed that increases in evaporation since 1995 exceeded the precipitation in most years. Comparing to 1989 total annual evaporation from the lake increased by 32.4 mm in 2019, which is 1.1 times higher than evaporation in 1989. However, during the period from May to October (2013–2019), monthly average lake water surface area has increased steadily, while the evaporation accounted higher than the precipitation. Based on the results, the authors assume that groundwater may strongly impact the water balance of Ogii Lake.
