Cleaner air may be driving Europe’s ‘increasingly intense’ heatwaves, say researchers

Heatwave time [image credit: BBC]

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This doesn’t quite fit the current obsession with carbon dioxide, which makes a nice change. However, the usual ‘greenhouse gas’ assertions are still there in the background, but the idea that trying to reduce them could change the weather looks as weak as ever. The argument now is that Europe would have warmed more pre-1980 if the aerosols, which climate models underestimated, hadn’t got in the way.
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Europe’s increasingly intense summer heatwaves may be partly linked to one of the great successes of modern environmental policy: The removal of air pollution, says Brussels Signal.

New research by scientists at the Barcelona Supercomputing Centre and the UK Met Office, reported by The Telegraph, suggests that the sharp reduction in sulphate aerosol emissions since the 1980s has not only allowed more sunlight to reach the Earth’s surface, but has also altered atmospheric circulation in ways that can intensify and prolong heatwaves over Europe.

The study, published in Geophysical Research Letters, examined why European summer temperatures have risen significantly faster than climate models had previously predicted.

It found that the decline in sulphate aerosols was a major contributor to the additional warming observed since around 1980.

Aerosols are tiny particles suspended in the atmosphere. Sulphates, produced largely by burning fossil fuels, can reflect sunlight back into space and have a cooling effect.

Reducing them has therefore improved air quality and delivered major health benefits, but it has also removed part of the atmospheric “sunshade” that had been offsetting some warming.

“On the one hand, the cleaner air lets more sunlight reach the surface,” Markus Donat of the Barcelona Supercomputing Centre said in The Telegraph. “On the other hand, we think that this additional energy causes atmospheric circulation changes that bring even more heat to Western Europe.”

The researchers found that the reduction in European sulphate emissions altered temperature patterns between different parts of the Northern Hemisphere.

Those changes affected quasi-stationary Rossby waves, large-scale atmospheric patterns that can become unusually persistent and help create the high-pressure systems associated with prolonged heatwaves.

The result can be a kind of meteorological “traffic jam”, in which weather systems move more slowly and hot air remains trapped over Europe for longer.

The study found that current climate models have underestimated the role of these circulation changes. According to the researchers, models had suggested that the relevant changes in atmospheric circulation would slightly reduce European summer warming. The observed effect, however, was the opposite, with circulation changes amplifying the additional warming linked to aerosol reductions.

Pedro Roldán-Gómez, one of the study’s authors, said that Europe had warmed around 1°C more than the average of extratropical areas of the Northern Hemisphere since 1980, and around 1.5°C more than the global average.

“Most of this excess warming over Europe can be linked to the reduction of particle emissions,” he said.

Full article here.

Source: https://tallbloke.wordpress.com/2026/07/26/cleaner-air-may-be-driving-europes-increasingly-intense-heatwaves-say-researchers/