"Hot" April in Greece: why heat waves persist, what research shows

According to weather forecasters, the first 10 days of April will be very hot. The air temperature will be 15-16 degrees higher than normal for the season.

It is possible that the thermometer will approach or even exceed +30°C in some parts of mainland Greece, reports meteo.gr. It is worth noting that the amount of precipitation in the country is also decreasing, which leads to increased droughts.

However, such anomalies occur not only in this Mediterranean country, but also on a global scale. The researchers analyzed heat waves between 1979 and 2020 and noticed that their average duration increased from about 8 hours in the 1980s to 12 at the end of the period studied.

According to a study published on 03/29/2024, extreme heat waves are increasingly showing a trend of increasing duration, which is mainly associated with climate change.

How do heat waves travel?
Previous studies have mostly focused on the frequency and intensity of heat waves, but few have examined how they move through space and time. Heat waves, like storms and other meteorological phenomena, are driven by winds, Wei Zhang, one of the authors of the study, which was published on the website of the scientific journal Science Advances, explained to AFP. And this means that “they may remain in an area for a longer period of time” and this “has great consequences for the local population.”

What the study shows
The researchers analyzed the heat waves using models based on weather radar and satellite observations. Their analysis showed:

• every decade, the speed of heat wave propagation decreased by about 8 kilometers per day,
• the average duration of heat waves increased from 8 hours in the 1980s to 12 hours at the end of the study period,
• heat waves now travel much further than before,
• an increase in the frequency of these phenomena has been confirmed.

The role of climate change
The researchers then looked at the role of climate change. To this end, they used climate models to simulate two scenarios – with and without greenhouse gas emissions – and compared the results with real behavior of heat waves. “We are very clear that the dominant factor explaining this trend is anthropogenic, in other words, that it is due to 'greenhouse gases,' which in turn arise from human activity,” said Wei Zhang of Utah State University. .

The expert noted that he is particularly concerned about cities experiencing heat waves because they may lack vegetation or cool places for less privileged residents who do not have air conditioning. “Heat waves that travel further and move more slowly will have more devastating consequences for nature and society in the future if greenhouse gas emissions continue to rise,” the researchers warn.

Scientists believe that if you do nothing, global warming will approach 4 degrees in the future. This will lead to deadly heat waves, millions of people losing their homes due to rising sea levels, and the permanent extinction of plant and animal species.

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