Is UK's worst ever rain linked to 'scary' unexplained warming of Atlantic?
The Atlantic's sea temperature has been getting warmer for 13 months, but scientists don't know why - and it could be linked to the UK's record wet weather.
Thirteen months ago, the temperature of the sea surface of the Atlantic leapt up a huge amount that was way out of the normal range. The temperature has remained more than 1C higher than normal ever since – and no-one is quite sure why.
Yahoo News spoke to University of Reading expert Dr Till Kuhlbrodt about why sea surface temperatures of the Atlantic might be so high – and what it might mean for the British weather and the future of climate change.
Temperatures in the world’s oceans are at a record high, with the global average having hit 21.06C in February, according to the EU's Copernicus Climate Change Service (C3S). But the change in the temperature of the Atlantic has been rapid and unexpected, says Dr Kuhlbrodt.
"All of a sudden it jumped out of the way of your usual range for that time of the year. It’s left the envelope where it usually is, and because it’s been going for 13 months, it’s obviously not a blip. That’s why we started analysing and looking into what could cause this. It’s something we haven’t seen in many decades," he adds.
Dr Kulbrodt is not the only scientist concerned about warming water temperatures around the world. Rob Larter, a Cambridge, England-based marine geophysicist who studies arctic ice levels, recently told the New York Times: "It's quite scary, partly because I'm not hearing any scientists that have a convincing explanation of why it is we've got such a departure.
"We're used to having a fairly good handle on things. But the impression at the moment is that things have gone further and faster than we expected," Larter continued. "That's an uncomfortable place as a scientist to be."
Professor Eliot Jacobson, retired professor of mathematics and computer science, has been tracking the temperature rise on X (formerly Twitter), described the situation as "bananas".
One way to see just how truly "gobsmackingly bananas" North Atlantic sea surface temperatures are right now is to remove the "less anomalous" year 2023 from the graph.
This just looks impossible in real life. pic.twitter.com/LozDoHAxpp— Prof. Eliot Jacobson (@EliotJacobson) April 24, 2024
Earth’s oceans absorb 90% of the excess energy accumulated by our planet, which is caused by heat-trapping gases from human activity. At present, the planet is absorbing 1.9 watts more energy per square metre than is radiated back into space. Per year, that’s an amount of energy equal to 300 times the amount of electricity used worldwide.
What could it mean for the UK?
The Atlantic surface temperature rise could lead to changed weather patterns – and may even be behind recent months of soggy weather in the UK.
England had a record amount of rainfall in the 18 months to March, according to provisional figures from the Met Office released earlier this month.
Some 1,695.9mm of rain fell from October 2022 to March 2024. This is the highest level for any 18-month period in England since comparable Met Office data began in 1836.
Sea surface temperature rises are linked to disrupted weather, Dr Kuhlbrodt explained, because air can hold more water when it’s warmer.
"That means there is a much higher risk for very intense precipitation, especially for us here in Western Europe – geographically, we are downstream," he added.
But the warmer sea surface has also disrupted the jet stream – the winds about five to seven miles up which blow from west to east, said Dr Kuhlbrodt.
"The jetstream winds which normally come straight across are more meandering in the UK, thanks to the warmer temperature, so we have longer phases of very, very wet weather.
"But there’s also a likelihood of longer periods of dry weather: so we have risks of flooding and flash flooding, then droughts and risk of wildfire and having to look at the water supply."
Research carried about by the University of Reading in 2012 following a dismal summer also questions whether there is a link. "Computer simulations suggest that these changes in ocean temperature affect the atmosphere above. Warmth in the North Atlantic causes a trough of low pressure over western Europe in summer and steers rain-bearing weather systems slap-bang into the UK.
Professor Rowan Sutton, Director of Climate Research in the National Centre for Atmospheric Science and a researcher in the University of Reading's Walker Institute, said at the time: "The North Atlantic ocean has alternated slowly between warmer and cooler conditions over the last 100 years. We saw a rapid switch to a warmer North Atlantic in the 1990s and we think this is increasing the chances of wet summers over the UK and hot, dry summers around the Mediterranean - a situation that is likely to persist for as long as the North Atlantic remains in a warm phase."
Could it be linked to shipping?
The team investigated whether tiny particles from burning fuel could be behind the rise. Since 2020, an agreement with major ship owners in the Atlantic has seen a shift towards higher quality fuels, which means much less soot and sulphur emissions.
These particles have a cooling effect, by reflecting sunlight, so the team investigated the idea there might be a warming effect from the reduction in soot.
"There is a detectable effect, but it’s small – not enough to explain this temperature rise," Dr Kuhlbrodt explained.
Is it a glimpse of the future?
The team’s calculations show that the Atlantic warming, which coincided with devastating floods in Europe and wildfires in Canada, is what we can expect as the ‘new normal’ if the world warms by 3C.
"If you actually reach global warming of 3C at some point this century (hopefully not) then this would be the new normal," Dr Kuhlbrodt said. "This is what we will run into if we don't really begin to take drastic measures, reducing the use of fossil fuels and reducing carbon emissions."
The researchers say that there’s a potential link between the warming in the Atlantic and record-low levels of sea ice in the Antarctic, which suggests a change in ocean currents, and possibly, according to Dr Kuhlbrodt, "hidden climate connections between the poles".
He added: "It appears that for the past seven or eight years, the north Atlantic is warming faster. Could there be some sort of circulation change that leads to stronger warming in the North Atlantic? That’s definitely something we want to explore."