Are tornadoes linked to climate change?

Global warming could facilitate tornadoes, but scientists are cautious about talking about a direct link.

Many previous studies have shown a strong link between climate change and extreme weather events, from record heat this summer in North America to flooding in Western Europe, but still There are huge gaps in our scientific understanding of tornadoes, as well as how they relate to global warming.

Tornadoes swept through southern Wynnewood, Oklahoma, USA.

"Over the past few decades, at least, we've seen a trend toward more favorable conditions (for tornadoes), especially during winter in the midwest and southeastern US. However, it's possible that it's possible," he said. It would be wrong to attribute this event to climate change," said expert John Allen from Central Michigan University.

Climatology professor James Elsner at Florida State University likens this to the link between smog and car crashes: foggy conditions on the road may be linked to a higher number of crashes, but accidents Accidents caused by individuals in dense fog are unlikely to be due to poor visibility.

Likewise, the direct link between climate change and cyclones is a topic that needs further investigation.

The idea is to feed climate data into computer models to analyze the probability that specific extreme weather events will occur in a "climate-free" world, compared to a world where climate change will not occur. We live in today, but such studies take time to perform and are particularly complex for tornadoes, which are more difficult to model than other extreme weather events because of the lack of relative data.

It is still too early to say with certainty that climate change will increase the frequency of winter monsoons.

Debris in the town of Mayfield, Kentucky, USA, on December 13.

In fact, the average number of tornadoes per year in the US has not increased in recent years, hovering around 1,300, most occurring in the spring.

"Most months show a decrease in tornado numbers and tornado days over 30 or even 40 years, with the exception of December and January which see an increase in tornado activity. over the same period - a finding that is 'quite consistent' with the potential explanation for the climate," added University of Illinois atmospheric scientist Jeff Trapp.

Tornadoes form from thunderstorms, when warm, moist air meets colder air with rain or hail. This creates vortex air currents that start horizontally and can grow vertically.

"In recent years, a trend has been seen to be more likely to have warm days during the cool season. These conditions can support thunderstorms and tornadoes," Trapp said.

What's more, as tornadoes form, outbreaks become more intense, even though the total number of hurricanes for the year is about the same, says Columbia University researcher Chiara Lepore.

Finally, the scientists noted a shift to the east of the United States in what is now known as a "tornado valley," with more hurricanes likely to make landfall in Arkansas, Mississippi or Tennessee - all three regions. were all affected by the "tornado disaster" a few days ago.

What will happen next? The problem scientists have with studying tornadoes is that they are transient, small, and difficult to track on climate models, unlike larger events like hurricanes or heat waves. Therefore, they can only study changes in conditions that "may be beneficial" for their formation.

A recent study found that for each degree Celsius warming, the likelihood of a severe thunderstorm in the US increases by 14-25%. Lepore, the study's lead author, said it is still difficult to deduce this will lead to more tornadoes.

According to another forthcoming report co-authored by Trapp, the researcher predicts tornadoes may become more powerful in the future, but violent tornadoes or super-tornadoes remain "rare events." not "the new normal".

"We're in the early stages of understanding the link between climate change and what we call severe local storms, including tornadoes and hail. In the next five or 10 years, I think it will be." there's been some real progress," Elsner said.