Winter storm rainfall ‘made 20% heavier by climate change’

Emily Beament, PA Environment Correspondent

Downpours in the storms which battered Ireland and the UK last autumn and winter were made around 20 per cent heavier by climate change, scientists have said.

A rapid attribution study has assessed the role of rising temperatures in the storms and heavy rain which led to at least 13 deaths and widespread damage across the two countries, as more than a dozen severe storms swept in between October and March.

It found that autumn and winter storms over Ireland and the UK were becoming wetter due to human-caused global warming.

One of the scientists involved in the study issued a blunt warning that “climate change is already making life shittier”, while another expert said the winter storms made things worse for people already struggling with the cost-of-living crisis, and hit physical and mental health.

Ireland and the UK saw 13 to 14 severe storms in 2023/24, 11 of which were named as part of a western Europe warning system.

They led to severe and repeated flooding and power outages, disrupted travel, caused the loss of crops and livestock, and left farmers with waterlogged fields which they could not plant in the spring.

Severity

The research used weather data and climate models to compare the storm severity and associated rain, as well as rainfall over the storm season, between today’s world and the cooler climate before industrialisation.

Human activity, such as burning fossil fuels, which puts climate-warming greenhouse gases into the atmosphere, has pushed up temperatures by around 1.2 degrees since the pre-industrial period.

The study found human-induced climate change had led to the average rainfall on stormy days becoming around 20 per cent heavier.

It said the kind of intense storm rainfall seen in 2023/2024 had become 10 times more likely.

Where it would have occurred about once every 50 years in the pre-industrial period, in today’s world, similarly intense storm rainfall was expected to occur around every five years.

The study also looked at the total rainfall for October to March, which was the third wettest such period on record for Ireland and the second wettest for the UK, and found climate change had increased rainfall over the season by 6 per cent to 25 per cent.

The wet conditions seen in 2023/2024 would have occurred every 80 years at most in the cooler, pre-industrial era, but were now considered to be four times more likely, occurring about once every 20 years.

If temperatures rose further to 2 degrees of warming, storm rainfall and seasonal rain would increase, the researchers said.

A warmer atmosphere holds more water vapour, a key factor in climate change driving heavier rainfall.

But the “storminess” of the storms showed a decreasing trend in this study, highlighting that more research was needed on how climate change might influence the severity and frequency of windstorms in northern Europe, the researchers said.

Until the world reduces emissions to net-zero, the climate will continue to warm, and rainfall in the UK and Ireland will continue to get heavier.

Sarah Kew, researcher at the Royal Netherlands Meteorological Institute, warned that Ireland and the UK “face a wetter, damper and mouldier future due to climate change”.

She said: “While the influence of climate change on strong storm winds is less clear, autumn and winter rainfall has become much heavier, bringing more damaging and sometimes deadly floods to urban and agricultural areas.

“Until the world reduces emissions to net-zero, the climate will continue to warm, and rainfall in the UK and Ireland will continue to get heavier.”

And Friederike Otto, senior lecturer in climate science at the Grantham Institute – Climate Change and the Environment, Imperial College London, said: “To put it bluntly, climate change is already making life shittier.

“Wetter winters are flooding farms, cancelling football matches, and overflowing sewage systems.

“Groceries are becoming more expensive and Brits holidaying in Europe are having to shelter from record-breaking heatwaves and wildfires.

“Thankfully, we know the solutions – replace oil, gas and coal with cleaner, cheaper renewable sources of energy, insulate homes, restore nature.”

“All this will make life cheaper and better for all, not more expensive,” she added.

The World Weather Attribution study involved scientists and experts from Met Éireann, the Royal Netherlands Meteorological Institute, the UK's Met Office, Imperial College London and the Red Cross.