Scientists have warned that mild temperatures in parts of Europe's this winter are an extreme weather event caused by climate change — on a par with the heatwaves that hit the continent last summer.
They said that Europeans are ill-prepared for such extremes, which they predict will probably become the norm after 2050.
Temperatures close to 19°C were recorded in the Polish capital Warsaw on New Year's Day, while across the border in Belarus, they reached 16.4°C — 4.5°C higher than the previous record.
In Paris, temperatures were 5.5°C higher than average between December 19 and January 2.
Such out-of-season temperatures are boosted by the arrival of south-western subtropical winds. While these are not unusual, their intensity has increased with human-driven global warming.
Its main cause is the burning of fossil fuels since the start of the Industrial Revolution in the 19th century.
"Global warming reduces temperature differences between low and high latitudes, which can affect the atmospheric circulation in mid-latitudes. This could in particular lead to more high-pressure systems, keeping low-pressure systems off the European continent," said Gerhard Krinner, a climatologist and research director at the French National Centre for Scientific Research.
“This may in turn increase the intensity and duration of heatwaves.”
This winter's records show a similar deviation from the norm as those last summer, when temperatures during heatwaves were about 7°C higher than usual, said Serge Zaka, an agriculture and climate specialist who also heads French climate non-governmental organisation InfoClimat.
Figures published by the French national meteorological service, Meteo France, show that on average, temperatures over the summer were 2.3°C higher than normal.
But because current temperatures are comfortable, they are less attention-grabbing than in July, he said.
“Mild temperatures in winter are deceiving, because they feel pleasant and reduce energy bills, so people are less worried than when they reached between 40°C and 44°C,” said Mr Zaka.
Weather last July marked a milestone in some European countries, with recorded temperatures exceeding 40°C in the UK for the first time. This caused severe infrastructure disruptions, as British railway tracks were not made to cope with such heat.
Meanwhile, countries such as France and Spain battled with wildfires.
The relatively long duration of recent mild weather may impact food security in Europe, warned Mr Zaka.
Instead of lasting a few days, higher temperatures have persisted for the past two weeks and are expected to continue for another two.
Their impact on fruit trees and vines, which are tricked into believing spring has arrived and are starting to flower, is potentially dangerous, because buds might be killed by a cold snap in March or April.
Warmer than usual winters in the past five years have caused important losses in Europe’s agricultural sector.
Forecasting what the weather will be like for the rest of 2023 is a difficult scientific exercise, but the UK Met Office has already warned that Britain is likely to see mild conditions continue this month.
Mr Krinner said that on a global scale, 2023 will likely be warmer than 2022.
The planet is currently experiencing cooler than usual conditions in the eastern Pacific region due to the La Nina weather pattern, which is the opposite of El Nino, when temperatures in that region are warmer than usual.
“The current La Nina event, which lasted for three years, will soon be over and we will be heading towards neutral conditions. Because the Eastern Pacific is a large region, it’s fair to assume that global temperatures in 2023 will be higher than in 2022,” Mr Krinner told The National.
Climate change has been particularly noticeable in Europe in recent decades.
Temperatures are rising twice as fast in Europe compared to the rest of the world for reasons that are not yet entirely clear to scientists, said Francoise Vimeux, a climatologist and research director at the Institute for Research and Development, in Marseille.
On average, temperatures across the planet have increased by 1.1°C since the beginning of the 20th century, but in France they have gone up 1.7°C.
One reason may be that in Europe, Scandinavian countries pass through the Arctic Circle, where there is more snow than elsewhere in the continent.
As temperatures rise, snow melts, which in turn causes temperatures to rise even more rapidly. This phenomenon of “polar amplification” is well-known to scientist, said Ms Vimeux.
“White surface is replaced by dark surfaces which absorb solar energy more efficiently,” she told The National.
If Europe continues on its current weather trajectory, temperatures that were considered to be extreme in 2022 will become the norm after 2050, with temperatures as high as 50°C to be expected during the summer in southern European countries, she said.
“We’re talking about peaks for a couple of hours, not entire days,” said Ms Vimeux.
Climate change, and more particularly heatwaves, increases death rates, damages ecosystems, reduces agriculture yields and water resources.
“We are forced to adapt, because even if we stopped all CO2 emissions tomorrow, temperatures would continue to rise for the next 20 to 30 years,” said Ms Vimeux.
The World Health Organisation estimates that hot weather across Europe killed more than 15,000 people last summer.
Agricultural practices and eating habits across Europe will be at the forefront of this climate transformation, said Mr Zaka, as weather patterns currently common around the Mediterranean will move north.
Yields in southern Europe are likely to decrease as water supplies dry up. “We’ll have to focus on crops like olives, citrus, almonds, pistachio, and sorghum,” said Mr Zaka.
But it’s not all bad, he pointed out. Agriculture in north and north-east Europe might be positively affected by climate change.
“Thawing soils in Russia, Ukraine and southern Scandinavia will allow those countries to grow more wheat,” he said.
And more vineyards are “likely to appear in Belgium, Luxembourg and southern Britain,” added Mr Zaka.