Climate change makes extreme winter storms like Eowyn even stronger

(Bloomberg) — Winter Storm Iovine lashed Ireland and the U.K. with hurricane-force winds on Friday, causing blackouts for thousands and disrupting travel across northwestern Europe.

According to preliminary estimates from meteorological officials, Iovine was one of the most powerful storms to hit the region and possibly set new intensity records after passing through an “explosive cyclone”. Meteorologists are still calculating Iowyn’s damage, but the UK Met Office says the storm’s 114 mph (184 kph) wind speed near Mace Head is the fastest ever recorded in Ireland. . And Iovine’s low pressure – a key measure of a storm’s destructive potential – appears to be the lowest recorded in Northern Ireland since 1900.

Although there have been no studies that pinpoint the exact impact of a warming climate on Iovine’s ferocity, this is exactly the type of storm that is expected to strengthen as the climate warms. Research indicates that while climate change could mean a reduction in winter storms in north-western Europe, it could also make strong storms like Éowyn even stronger.

“Such storms are becoming more likely as the world continues to warm,” said Matthew Priestley, a research fellow at the University of Exeter.

Climate change does not necessarily create individual storms on its own. Instead, it works like a volume controller, amplifying what is naturally present. The extra heat in the atmosphere causes more evaporation from the oceans. This releases energy that can power storms while the wetter atmosphere causes more rainfall. When these intense storms make landfall, they are more likely to pose a threat to people and infrastructure.

Research shows that climate change is making winter and autumn storms wetter in the UK and Ireland – a 20% increase in rainfall is expected to worsen the situation, leading to more flooding and disruption to water systems, transport networks and everyday life. There will be disruption in life.

Ireland and Britain in particular are in trouble, Priestley said. They are near the Atlantic Ocean, a breeding ground for strong winter storms, and lie on a path that can line up low-pressure systems with the jet stream exiting the US.

In Europe and elsewhere outside the tropics, there may actually be fewer hurricanes due to a quirk of global warming: the Earth is warming faster at the poles and creating a smaller temperature gradient along lower latitudes. This has the ability to reshape the jet stream, which is influenced by that gradient.

That fast-moving river of air is “essentially pushing these storms very quickly across the Atlantic towards us,” said Hayley Fowler, a professor of climate change impacts at Newcastle University. But if it weakens or changes direction, as some climate models predict, it will change how these storms affect northwestern Europe, he said.

“We see these two opposing factors of overall reduction, but the strongest storms potentially become stronger,” Priestley said. Their research shows that there will be about 5% fewer hurricanes by the end of the century but a 4% increase in winter cyclones in the extreme Northern Hemisphere.

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