Identification of the surface temperature change in the Atlantic-European and Mediterranean regions using ERA5 re-analysis

A.B. Polonsky, S.S. Beytser

 Institute of Natural and Technical Systems, RF, Sevastopol, Lenin St., 28


DOI: 10.33075/2220-5861-2021-1-18-24

UDC 551.524.3 


   The article analyzes the seasonal, interannual and inter-decadal variability of the surface / drive temperature of the Atlantic-European and Mediterranean regions, as well as assesses temperature trends. The information is based on the data of the re-analysis of ERA5. This is one of the latest climate re-analyses, which was performed by specialists of the European Center for Medium-term Weather Forecasts (ECMWF) with a spatial resolution of 0.25°x0.25°. We analyzed hourly data for 41 years, from 1979 to 2019 for two periods: the entire re-analysis period and the thirty-year climate period from 1990 to 2019. The purpose of the analysis was to clarify the relative role of natural quasi-periodic changes in temperature and the trend component of presumably anthropogenic origin. The most important role of natural temperature changes on time scales from interannual to inter-decennial is confirmed. Linear temperature trends calculated over the last climate period of thirty years are responsible for the increase in temperature over the mainland areas to 3°C over 30 years. At the same time, over a significant part of the north-eastern Atlantic and adjacent land areas, the linear trends estimated over a thirty-year period are insignificant. Natural quasi-periodic components of variability prevail here. As the analyzed period increases, the areas of significant temperature trends expand. In the area of the Canary and Portuguese upwelling, a decrease in the driving temperature is observed, confirming the validity of the hypothesis of A. Bakun of the intensification of the eastern coastal upwelling systems in the contemporary climate epoch.

Keywords: temperature trends, interannual and interdecadal variability.

To quote: Polonsky, A.B., and S.S. Beytser. “Identification of the Surface Temperature Change in the Atlantic-European and Mediterranean Regions Using ERA5 Re-Analysis.” Monitoring Systems of Environment no. 1 (March 25, 2021): 18–24. doi:10.33075/2220-5861-2021-1-18-24.

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Originality – 88,66%


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