Response of the Mogan and Eymir lakes (Ankara, Central Anatolia) to global warming: Extreme events in the last 100 years

Abstract

Mogan and Eymir lakes are shallow wetlands which are potentially susceptible to global warming. Previous geological studies demonstrated several complete desiccation and shrinkage events in Lake Mogan since the 1800s. Archival records show at least three desiccation events in 1910, 1934 and 1938, and many severe shrinkages later. Here, the significance of climatic and anthropogenic drivers is still a subject of curiosity. The back-analysis of the hydrological data during the regulator intervention indicates that Lake Mogan would have dried out in 1974, and would have shrunk considerably in the years 2007/2008 and 2017/2018 if human intervention was not involved. Our lake budget analysis shows that, assuming no human intervention and stream recharge, the water level of both lakes would have dropped below the threshold level in less than a week by natural downstream discharge, and the remaining volume of the lakes would evaporate in less than two years. This fact indicates the benefits of regulators for the protection of the lakes. The meteorological and lake budget data suggest that the underlying climatic threat over the studied lakes is high frequency (sub-decadal) rainfall scarcity coupled with long-term (several decades) insolation increase but not slow, steady deterioration of the climatic parameters.