RUSSIAN JOURNAL OF EARTH SCIENCES, VOL. 19, ES3001, doi:10.2205/2019ES000657, 2019
Z. I. Stont, T. V. Bukanova
The paper is devoted to the analysis of air temperature variability over the coastal waters of the south-eastern part of the Baltic Sea. The study uses the data from the automatic hydrometeorological station located 20 km from the coast on the offshore ice-resistant fixed platform. The annual mean air temperature is $8.8 \pm 0.6$° C, which is 1.4° C higher than in the middle of the last century. The annual minimum of air temperature ($- 0.3$° C) has shifted towards February, therefore the climate of the south-eastern Baltic Sea has become more marine. The rise of monthly mean air temperature in 2004–2017 has revealed at a rate of $+ 0.005$° C/month, i.e. $+ 0.8$° C/period (according to the hourly observations of air temperature the increase accounts for 0.95° C for the same period). The greatest contribution to the variability of annual mean values of air temperature is provided by variations in the cold season (February and March). A close relationship between the North Atlantic Oscillation index and the air temperature is shown (correlation coefficient $r = 0.7$), which explains the dependence of detected air temperature variability from the circulation conditions. The lower values of the North Atlantic Oscillation index stipulate the intensification of anticyclonic activity and noticeable decrease of air temperature in the study area. The predominance of a positive phase of the North Atlantic Oscillation index causes the strengthening of the Icelandic Low and a west-east transfer what consequently results in the increase of air temperature. Western form of circulation by Wangenheim-Girs is prevailing in the study area. However, the enhancement of the eastern form of circulation by Wangenheim-Girs slows down the increase of air temperature.
Received 23 October 2018; accepted 30 November 2018; published 1 May 2019.
Citation: Stont Z. I., T. V. Bukanova (2019), General features of air temperature over coastal waters of the south-eastern Baltic Sea for 2004–2017, Russ. J. Earth Sci., 19, ES3001, doi:10.2205/2019ES000657.
Copyright 2019 by the Geophysical Center RAS.