Heatwaves in Greece Increase in Duration, Intensity and Frequency

A mini heatwave is expected to hit Greece until Saturday, according to Meteo.gr of the National Observatory of Athens.

According to the available forecast, this rise is expected to peak from Friday and reach 36 to 37 degrees Celsius in some areas.

Greece has experienced an average of 0.7 heatwaves per year from 1950 to 2020, but this average value has increased to 1.1 heatwaves per year from 1990 to 2020, according to a recent study.

The study published in the international scientific journal “Climate” says that there is a generally increasing trend in all characteristics of heat waves, including intensity, duration, and frequency of occurrence during the period 1950-2020.

The areas of Greece that experience at least one heat wave per year have almost doubled since 1990.

Regions on Greece affected by heatwaves

The regions of Greece in which there has been the greatest increase in heatwave episodes are the regions of Macedonia and Thessaly, as well as the western parts of Epirus and the Peloponnese.

Also, during the last two decades, a particularly large increase in the number of heatwaves that occurred in the month of June was detected.

The above are the main conclusions of a study by the researchers of the meteo.gr unit of the National Observatory of Athens (E. Galanaki, X. Giannaros, V. Kotronis, K. Lagouvardos, G. Papavasiliou).

The study covers the time period 1950-2020 using high-resolution (~10 km) meteorological data from the ERA5-Land database of the European Copernicus service.

As the researchers point out, prolonged periods of very high temperatures, i.e. heat waves, affect human thermophysiology by creating thermal stress, which in turn can even lead to premature death.

Heatwaves are the deadliest weather phenomenon

Heat waves are considered the deadliest weather phenomenon. For these reasons, climatological analyzes of heat wave characteristics and trends can make an important contribution to the establishment of a heat wave early warning system as well as the effective implementation of adaptation plans and improvement of preparedness by local authorities.

The study defines heatwaves as periods where two thresholds, based on a modified version of the Excess Heat Factor index (EHF) and the 95th percentile of the maximum daily temperature, were exceeded for at least three consecutive days.

Heatwaves also struck western Europe last summer which sparked devastating wildfires and prompted evacuations.

The intense heat led to deadly wildfires in Portugal, where at least 238 people died, according to the BBC, and in the southwest part of France, where over 12,000 people were evacuated.

This year the UK recorded its highest-ever temperature of 41° Celsius—105.8° Fahrenheit— on Monday. Meteorologists issued the country’s first-ever Red warning for extreme heat.