Modeling of Interannual Variations in the Total Duration of Thunderstorms in the Northern Caspian Region, Considering Atmospheric Precipitation Variability

The study of thunderstorm activity in the Northern Caspian as a risk factor for navigation, oil and gas infrastructure, power grids, and agriculture, as well as the need to improve monitoring and forecasting systems under changing climate conditions, is of great importance for the region. This paper analyzes long-term observations of thunderstorm activity in the Northern Caspian based on data from nine meteorological stations in Atyrau Region for the period 1977...2022. It was established that thunderstorms exhibit a quasi-periodic structure with cycles lasting 2...4 and 7...10 years. Using the example of the Atyrau station, it was shown that the total duration of thunderstorms in certain months reaches extreme values of up to 20...21 hours, reflecting the high interannual variability of the phenomenon. Statistical time-series modeling methods were applied to assess trends in the total duration of thunderstorms and to calculate forecast values for the coming years. The results indicate a decreasing trend in the average frequency and duration of thunderstorms in recent decades. The findings have practical significance for improving the reliability of monitoring and forecasting of hazardous atmospheric phenomena.