In this article we first present the temperature analysis at the level of 850 hPa (~ 1500 meters above the surface), a level that allows the monitoring of the thermal characteristics of the gas masses that affect an area.
The following map gives for the quarter June-August 2021 the total temperature deviation at the level of 1500 meters and which shows that the average temperature in our country moved above normal for the season with the temperature deviation exceeding 2 degrees Celsius in several areas of our country (red colors). Particularly noteworthy is the fact that positive temperature deviations prevailed in most of the northern hemisphere with the largest deviations being located in the western United States, the Mediterranean, Siberia and the western parts of Russia. So the summer of 2021 was a very hot summer.
Graph 1 : Temperature deviations at the isobaric level of 850 hPa (~ 1500 meters above the surface) during the summer months (June-August) of 2021 for the northern hemisphere.
Then we focus on our country and rank the last 43 summers (1979-2021) calculating the sum of the hours where the temperature at the equilibrium level of 850 hPa (~ 1500 meters above the surface) exceeds 99% of the temperature average values that have been observed for the last thirty years and which we define as warm hours .
The analysis shows that the summer of 2021 was the one with the hottest hours in the last 43 years, followed by those of 2007, 1987, 2000 and 2012 (Graph 2). The specific results are naturally related to the most important and extreme heatstroke episodes that occurred during these summers.
Graph 2 : Sum of hours per summer (June-August) during the period 1979-2021 where the temperature at the isobaric level of 850 hPa (~ 1500 meters above the surface) exceeds 99% of the temperature distribution values at 850 hPa with reference period in 1981-2010.
Source – meteo.gr – https://www.meteo.gr/article_view.cfm?entryID=1923