Human activities that spur global warming are largely to blame for changes in rainfall patterns over the last century, climate researchers reported on Monday.
The report was released as record rains caused deadly flooding in Britain and China.
Human-caused climate change has been responsible for higher air temperatures and hotter seas and is widely expected to lead to more droughts, wildfires and floods, but the authors say this is the first study to specifically link it to precipitation changes.
“For the first time, climate scientists have clearly detected the human fingerprint on changing global precipitation patterns over the past century,” researchers from Environment Canada said in a statement.
The scientists, writing in the journal Nature, found humans contributed significantly to these changes, which include more rain and snow in northern regions that include Canada, Russia and Europe, drier conditions in the northern tropics and more rainfall in the southern tropics.
So-called anthropogenic climate change has had a “detectable influence” on changes in average precipitation in these areas, and it cannot be explained by normal climate variations, they wrote.
Britain is braced for downpours across the country – but forecasters say it could also be one of the hottest days of the year.
The Met Office has issued a severe weather warning for the whole of England, Northern Ireland, Scotland and Wales while the Environment Agency has three flood warnings in place.
Warnings have been issued over potential flash floods, but forecasters do not expect conditions to be as bad as the torrential rain that caused misery for thousands of people last month.
The heavy rain will begin on Sunday morning in the south before battering the north of England and Wales during the afternoon. But once the rain has gone, forecasters say temperatures in parts of the country could top 26C (79F).
The cost of recent flood damage is expected to top £1 billion, insurers have said.
The Association of British Insurers (ABI) estimated that 27,000 homes and 5,000 businesses have been affected by the torrential rains that hit the UK earlier this week.
And the body warned that the overall cost of the damage could rise further, with more bad weather anticipated over the weekend.
The scale of the flooding led to a number of insurers putting into place crisis action plans to meet demand from stricken households.
More flooding has wrecked havoc on some parts of Britain following severe storms.
Gloucestershire, Worcestershire and Shropshire were worst hit, as many people were trapped in their homes and cars because of the extreme weather conditions.
One ambulance crew in Worcestershire was unable to reach a man stranded in his home after finding that a bridge had been completely submerged.
However, the crew were able to reach a second man who had suffered lacerations to his feet while wading through floodwater after a brook burst its banks.
West Midlands Ambulance Service said its crews had reported floodwaters rising to the height of car doors, forcing paramedics to reduce driving speeds for safety reasons.
Meanwhile, a clear-up operation was also under way in parts of Kent after a band of heavy rain prompted more than 300 flooding-related calls.
Flash floods in Britain are likely to be the biggest immediate problem caused by climate change, the government’s chief scientist warned today.
Sir David King told a committee of MPs that global warming has already altered the climate and the country will have to prepare for extreme weather such as heat waves and “torrential downpours”.
He said the summer of 2003, which killed an estimated 32,000 people across Europe, was a “climate change-driven event” and one of the world’s biggest natural disasters.
Global emissions of carbon dioxide are increasing three times faster than scientists previously thought, with the bulk of the rise coming from developing countries, an authoritative study has found.
The increase in emissions of the gases responsible for global warming suggests that the effects of climate change to come in this century could be even worse than United Nations scientists have predicted.
The report, by leading universities and institutes on both sides of the Atlantic, will create renewed pressure on G8 leaders who are meeting this week in Heiligendamm, on Germany’s Baltic coast.
Britain’s energy strategy is an incoherent mess which is unlikely to ensure future supplies or succeed in fighting climate change, according to a report by academics published on Monday.
“Britain’s energy policy just doesn’t stack up. It won’t deliver security. It won’t deliver on our commitments on climate change. It falls short of what the world’s poorest countries need,” the leader of the Oxford University Taskforce report on energy security, politics and poverty, Chris Patten, said.
The former minister said the government’s latest attempt to patch up its “hotchpotch” of energy and climate change policies — last month’s Energy White Paper — only highlighted the mess.
The report says Britain still has no coherent strategy for replacing the one third of electricity generation which is soon to be retired, much of it nuclear, leaving companies unsure of what to build and therefore building nothing.
The report’s panel said that policy on energy security, climate change and development aid is muddled and ineffective largely because it is handled by different government departments all pursuing different goals.