A parcel of studies looking at the oceans and melting Arctic ice confirm it is getting warmer, people are to blame, and the weather is going to suffer, climate experts said last night.
New computer models that look at ocean temperatures instead of the atmosphere show the clearest signal yet that global warming is well under way, said Mr Tim Barnett of the Scripps Institution of Oceanography.
Speaking at an annual meeting of the American Association for the Advancement of Science, Mr Barnett said climate models based on air temperatures are weak because most of the evidence for global warming is not even there.
"The real place to look is in the ocean," Mr Barnett told a news conference. His team used millions of temperature readings made by the US National Oceanic and Atmospheric Administration to calculate steady ocean warming.
"The debate over whether or not there is a global warming signal is now over, at least for rational people," he said.
The report was published one day after the United Nations Kyoto Protocol took effect, a 141-nation environmental pact the US government has spurned for several reasons, including stated doubts about whether global warming is occurring and is caused by people.
Mr Barnett urged US officials to reconsider. "Could a climate system simply do this on its own? The answer is clearly no," Mr Barnett said. His team used US government models of solar warming and volcanic warming, just to see if they could account for the measurements they made. "Not a chance," he said.
And the effects will be felt far and wide. "Anywhere that the major water source is fed by snow . . . or glacial melt," he said. "The debate is what are we going to do about it."
Other researchers found clear effects on climate and animals. Ms Ruth Curry of the Woods Hole Oceanographic Institution found that melting ice was changing the water cycle, which in turn affects ocean currents and, ultimately, climate.
"As the Earth warms, its water cycle is changing, being pushed out of kilter," she said. "Ice is in decline everywhere on the planet." A circulation system called the Ocean Conveyer Belt is in danger of shutting down, she said.