Characteristics of the Wind Regime in the Northwestern Part of the Caspian Sea

Abstract

The regional features of the wind regime in the northwestern part of the Caspian Sea are considered. The seasonal and annual dynamics of the main characteristics of the wind regime over a long-term period and in the current trends in their change are assessed. The analysis of time series of the average wind parameter values showed that easterly winds prevail in the northwestern part of the Caspian Sea, with the average long-term frequency being 26%. Despite their stability throughout the year, some seasonal variability can be observed. Among the winds of other directions, southeasterly, westerly, and northwesterly winds should be noted. Positive seasonal and annual dynamics are observed for the southeasterly wind. Characteristic features are also observed for the average wind speed; in the period 1991–2020, an increase in the climatic norms of 0.2–0.6 m/s is observed. Regional trend estimates obtained from the time series of the average annual air temperature and average wind speed show that the average wind speed increases along with an increase in the average annual air temperature. The main contribution of the trend to the change in wind speed by direction belongs to the spring and winter seasons. In the northwestern part of the Caspian Sea, weak winds prevail, most often in the gradation of 4–5 m/s. Average wind speeds of ≥15 m/s are observed in all seasons, with the highest frequency being noted in spring and autumn. The results obtained are of practical interest, since the need for marine climatological data arises when carrying out various activities.