The global scientific body on climate change will report soon that only greenhouse gas emissions can explain freak weather patterns.
Simultaneous changes in sea ice, glaciers, droughts, floods, ecosystems, ocean acidification and wildlife migration are taking place. The Intergovernmental Panel on Climate Change had previously said gases such as CO2 were "probably" to blame. Its latest draft report will be sent to world governments next month.
A source told the BBC: "The measurements from the natural world on all parts of the globe have been anomalous over the past decade. "If a few were out of kilter we wouldn't be too worried, because the Earth changes naturally. But the fact that they are virtually all out of kilter makes us very concerned."
He said the report would forecast that a doubling of greenhouse gas concentrations in the atmosphere would bring a temperature rise of 2-4.5C, or maybe higher. This is an increase on projections in the last IPCC report, which suggested that the rise could be as little as 1.5C.
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http://news.bbc.co.uk/1/hi/sci/tech/4761804.stm