The UN's official panel on climate change has rejected sceptics' claims the case for human influence on global warming has been overstated.
In a statement, the Intergovernmental Panel on Climate Change (IPCC) said it was "firmly" standing by findings that a rise in the use of greenhouse gases was a factor.
It was responding to a row over the reliability of data from East Anglia University's Climatic Research Unit. Leaked e-mail exchanges prompted claims that data had been manipulated.
However, the IPCC said it was standing over those findings "and by the community of researchers worldwide whose professional standards and careful scientific work over many years have provided the basis for these conclusions".
It said the key finding - that warming in the climate system is unequivocal - "is "based on measurements made by many independent institutions worldwide that demonstrate significant changes on land, in the atmosphere, the ocean and in the ice-covered areas of the Earth".
"Through further, independent scientific work involving statistical methods and a range of different climate models, these changes have been detected as significant deviations from natural climate variability and have been attributed to the increase of greenhouse gases."
The IPCC said the "internal consistency from multiple lines of evidence strongly supports the work of the scientific community, including those individuals singled out in these email exchanges".
The UN body said the conclusions of its research conclusions of the Fourth Assessment Report had undergone scrutiny through reviews by peers and governments, refined to take into account these review comments, and approved "word by word" by the governments of the world.
The IPCC statement was signed by Prof Thomas Stocker and Prof Qin Dahe, co-chairmen of the panel's working group.
Police are investigating the theft of the East Anglia data, which include more than 1,000 emails sent from or to members of the Climatic Research Unit,