Climatic characteristics of the east coast caspian sea fogs and their changes during 1970-2020

Abstract

In the Caspian Sea, fogs of varying intensity are observed throughout the year. The research aimed to determine the number of days with fog and their duration (in hours) for each month from 1970 (1986) to 2020 at four meteorological stations: Kulaly Island, Fort Shevchenko, Tushchibek, and Aktau. The study included statistical analysis and assessment of climate change in the form of fog indicator longterm series approximation based on two non-stationary average models, including the evaluation of their efficiency and statistical significance. The assessment of climate change revealed the most significant reductions at the Tushchibek and Fort Shevchenko Stations, with decreased fog conditions observed in summer and autumn. At the Kulaly Island Station, the changes were detected in autumn; and were practically absent at the Aktau Station.