Several European countries are expected to see Mercury rise again on Wednesday as high-pressure zones continue throughout the continent. Experts warn that swelling temperatures have become the norm.
“Extreme heat is no longer an unusual event. It’s a new normal,” UN Secretary-General Antonio Guterres said earlier this week.
The extraordinarily high temperatures that hold Europe are caused by the phenomenon of thermal domes, high pressures remaining in a wide area, trapping hot air.
But the extent to which human-induced global warming is due to decades of fossil fuel pollution exacerbates such extreme heat episodes.
Scientists warn that individual weather phenomena are directly attributed to climate change. These episodes happen regardless.
However, there is a scientific consensus that global warming is making heat waves more frequent, more intense and longer, with potentially disastrous consequences for people’s health.
There is a hot heat wave here to stay
Recently, Carbon Brief researchers mapping All published scientific studies detailing how climate change has affected extreme weather.
This analysis covers 116 heat-related events in Europe. Of this total, scientists considered to be 110 (95%) were more severe or more likely due to climate change.
The June heat wave is about 10 times more likely to occur today than in the pre-industrial era due to the effects of climate change, and scientists with global weather attribution estimate.
Others say that most atmospheric events that drive heat waves have The strength and duration have been tripled Since the 1950s.
A heat wave is defined as a period of longer periods of higher than normal temperatures (usually lasting for at least three days). This means that the temperature of the heat wave threshold varies between countries and within borders.
For example, the temperature must rise to 39°C over a long period of time in Athens for heat waves to occur. In Helsinki, just 25°C is required to meet the standards.
These events occur more frequently, and are more likely to cause heat wave conditions, as average temperatures are generally high due to climate change.
Valerio Lucarini, a climate scientist at the University of Leicester, explains that deviations from expected weather patterns are also “permanent.”
“The dynamics change in the atmosphere make it more likely to be called block flow,” explains Professor Lucarini, referring to a stationary, high-pressure system that leads to long-term heat. “These patterns allow for the occurrence of major temperature anomalies and permanent things.”
The heat wave in Europe may be hotter and drier than other similar events in recent years due to human-driven climate change. study It is led by Professor Lucarini and Climameter’s European group of scholars.
“We are seeing a record heat wave on the continent at this point,” said Samasa Burgess, deputy director of Copernicus Climate Change Services in the EU.
“This heat wave is worth noting for three reasons: the maximum temperature intensity is predicted over a wide area.
Burgess added that extreme early and extremely hot periods of summer become more common, extending periods of time when there is a risk of severe heat stress.
Europe is particularly vulnerable
Europe is the fastest continent, with average temperatures rising around 0.5°C per decade compared to 0.2°C worldwide.
Because it is close to the Arctic Circle, the fastest part of the Earth, it contributes to this rapid warming and makes it vulnerable to heat waves.
Of the 30 most severe heat waves that struck Europe between 1950 and 2023, 23 of those occurred since 2000, according to the World Meteorological Organization (WMO) European Regional Climate Centre.
Scientists also believe that Southern Europe and the Mediterranean are particularly exposed due to its geographical location between North Africa’s arid subtropical and wet regions of Northern Europe.
2020 study This concludes that the Mediterranean has an unusually high surface pressure, bringing heat and dry air from the Sahara to Morocco and southwestern Europe. This creates more frequent dry springs, and is preferred for summer droughts and heat waves.
Scientists also say that the changing behavior of the jetstream – the rapid currents surrounding planets from west to east – can explain why Europe and North America are increasingly exposed to heat waves, and sometimes simultaneously.
A phenomenon known as the “double jet stream” – airflow remaining on the continent – is the main cause of rising heat waves in Western Europe, and German researchers I said 2022.
How about ocean heat waves?
European land areas warm up faster than the ocean, but the Mediterranean is now June.
“When the seawater gets warmer, it evaporates more and heats the atmosphere above it. And that evaporation produces more potential energy for the storm. So there’s this feedback between the atmosphere and the ocean.”
Professor Lucarini pointed out that current heat waves are consistent with periods of unusually high temperatures (4-5°C above average) in parts of the Mediterranean.
“We see huge sea surface temperature anomalies throughout the Western Mediterranean and the East Atlantic,” he explained.
“Take France, it is surrounded by very hot water, so obviously it tends to have long, lasting temperature anomalies on the land and have very strong thunderstorms.”
Wide range of results
It is estimated that cold climates cause death in Europe 10 times more than heat. However, changing climate conditions can lead to fever-related deaths.
A European Commission study estimates that without climate mitigation and adaptation, the death toll from extreme heat in the European Union and Britain could be 30 times higher by the end of this century.
At the same time, fever-related deaths in southern Europe are expected to be 9.3 times more frequent than in northern Europe, compared to six times more frequent than in northern Europe.
Extreme heat can cause other extreme weather events, such as subtropical storms, droughts, and wildfires.
“The hotter the temperature is, the more it evaporates from the moisture in the soil. The dryer the soil, the dryer the vegetation is, meaning the greater the risk of a fire,” Burgess said.
All this means that Europe needs to be prepared more and more for hot episodes and their impacts from a health and public safety perspective.
