Future drought projections with CMIP6 in Eğirdir Lake basin (Türkiye)

In recent years, serious problems have been experienced in Turkey as well as in the world due to drought events. Accurate drought forecasts are critical for future planning on issues such as the use of water resources, agricultural activities and human health. In this study, data obtained from global circulation models produced within the scope of CMIP6 were used to determine the effects of global climate change on Lake Eğirdir basin. For this purpose, precipitation and temperature data from CANESM5, EC-EARTH3, MIROC6 and MRI-ESM2 climate models were reduced to meteorological station basis using statistical downscaling method. In this context, future (2020–2100) precipitation and temperature forecasts were made for four different meteorological stations located in the Lake Eğirdir basin. In addition, future precipitation and temperature data based on different Shared Socioeconomic Pathways (SSP1-1.9, SSP1-2.6, SSP2-4.5, SSP3-7.0, SSP4-6.0 and SSP5-8.5) were predicted with the CanESM5 model, which was determined to be the most appropriate according to model performance tests. Accordingly, it is predicted that precipitation and temperature characteristics in Lake Eğirdir Basin will change significantly both spatially and temporally in the future. According to almost all of the SSP scenarios, it is predicted that there will be a decrease in annual average precipitation amounts. At the same time, in the SSP5-1-1.9 scenario, which is defined as the best scenario, annual average temperatures are predicted to increase by approximately 3 °C. Drought analyses were made by using the Standardized Precipitation Index (SPI) method by using these data estimated for the future. In drought projections made until 2100, it is predicted that more frequent, longer and more severe droughts will be experienced in the coming years. The findings obtained show that it is very important to develop short-, medium- and long-term drought management strategies for decision makers in order to minimise the effects of droughts that may be experienced in the coming periods by using surface and groundwater efficiently in the Lakes Region.