Caspian Sea: State of the Environment 2019

In Kazakhstan, the 2007–2016 ten-year average for air temperature was +6.5°C, exceeding the norm for the 1961–1990 period by +1.01°C.This was the sec- ond biggest positive anomaly after the record-warm decade of 1997–2006. The 2012–2016 five-year av- erage for annual air temperature was +6.66°C, the highest it has been since 1941. Between 1976 and 2016, the ten-year average increase in annual air temperature across Kazakhstan was 0.34°C. There is also a significant increasing trend in the num- ber of days with temperatures above 35°C, which in the western part of Kazakhstan in Atyrau and Mangystau Regions, is 4–8 days every 10 years. Throughout the country, the total duration of heat waves is increasing too by 6–10 days every 10 years and the number of frost days is decreasing by 3–8 days every 10 years (Kazhydromet 2016). According to CASPCOM, the average air tem- perature on the Russian coast of the Caspian Sea has increased in the last 30 years (1987–2016) compared with the average temperature for 1961– 1990, rising from 9.9°C to 10.7°C in Astrakhan, from 12.2°C to 12.5°C in Makhachkala and from 12.7°C to 13.5°C in Derbent. It should be noted that regardless of the increase in average air tem- perature in the last 50 years, or its decrease in the last 10 tens, the overall average rate of air tempera-

ture increases is decreasing, and was negative for the 2012–2016 period (CASPCOM 2017). This indicates that climate warming in the Caspian re- gion has been slowing down in recent years. Within the framework of preparing the First Na- tional Communication on Climate Change is- sued by Turkmenistan, annual and seasonal data from 30 meteorological stations located in differ- ent physical and geographical areas throughout the country were analysed to study its tempera- ture and atmospheric precipitation patterns. The analysis showed that autumn and winter months had become colder by 0.2–0.6°C, while spring and summer months had become warmer by 0.3–0.9°C (Atamuradova 2012). In the Caspian Sea, increases in the water tem- perature and air temperature over the water are of great importance. Any increase in water tem- perature is especially significant, as it decreases the area of winter ice cover in the Northern Caspian, weakens vertical water circulation in the deep sea, increases evaporation and activates chemical and biological processes. According to CASPCOM data (CASPCOM 2017), the average water tem- perature in the Makhachkala area for the 1986– 2015 period was 12.9°C, which was 0.4°C higher

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