Features of Forming the Water Extreme Thermal Regimes in the Kuril Ridge Region in Summer under the Impact of the Changeable Atmospheric Processes
Purpose. The work is aimed at identifying the mechanisms forming the water extreme thermal regimes in the Kuril Island ridge region in summer under the impact of the atmospheric processes over the past four decades. Methods and Results. The data resulted from the longterm observations at the Rosgidromet coastal stations in 1977-2019 permitted to study multi-year variability of the water thermal regime in the South Kuril and North Kuril fishery regions. The extreme fluctuations in the summer sea surface temperature in certain years were revealed. Used the cluster analysis method, the years with the opposite and the same extreme thermal regimes in the ridge southern and northern parts were determined. Variability of the characteristics of the atmospheric action regional centers was researched. It was established that formation of the extreme thermal regimes was conditioned by the abnormal changes in development of the Okhotsk anticyclone, formation of the troposphere trough in the altitude field, displacement of the summer Far East depression from its mean multi-year position, changes in propagation of the North Pacific maximum (the Hawaiian anticyclone) to the north-west, and also by the corresponding atmospheric circulation. The features of the mechanisms that form the abnormal cold or warm thermal regimes in the northern and southern areas of the Kuril ridge are shown. The cause and effect relationships are revealed. Conclusions. In the certain areas of the Kuril ridge, the abnormal water thermal conditions are formed by the local impact of the abnormal atmospheric circulation that is the extreme fluctuations both in the development intensity of the atmospheric action regional centers and in their location