Serykh I.V., Kostianoy A.G.
Analysis of the monthly average data of the temperature of the Baltic Sea on the surface and various depths showed its significant growth over the past decades. At the same time, the observed temperature increase is not evenly distributed throughout the Baltic Sea, as the temperature increased most strongly in the Gulf of Finland and Riga. Against this growth, temperature oscillations with periods ranging from 2 to 6 years, ~8 years and ~14 years were found. The relationships between these oscillations and the El Niño, the North Atlantic Oscillation and the North Atlantic Current, respectively, are shown. It was found that the influence of El Niño captures the top 10 meters of the Baltic Sea, the connection with the North Atlantic Oscillation is traced to a depth of 52 meters, and the influence of the North Atlantic Current is maintained to a depth of 78 meters. It has been shown that these fluctuations exerted the strongest influence on the temperature of the Baltic Sea from the mid‐1970s to the end of the 1990s. The influence of global climate shifts 1976/77 and 1998/99 on interdecadal changes in the temperature of the Baltic Sea has been detected. It has been suggested that the Global Atmospheric Oscillation acts as a synchronizing link between the El Niño, the North Atlantic Oscillation and the interannual variability of the temperature of the Baltic Sea.
