Emails stolen from one of the world's leading climate change research centers contained no evidence to undermine the case for manmade global warming, a report found on Wednesday.

An investigation into the British research unit cleared its scientists of serious wrongdoing, but criticized their lack of openness and said some of their data was misleading.

The University of East Anglia, eastern England, launched the inquiry after 1,000 emails hacked from its climate research unit were put on the Internet and held up as evidence scientists had exaggerated or lied about man's role in global warming.

The leak's timing, just before U.N. climate talks in Copenhagen last December, was awkward for policymakers and scientists trying to persuade an often skeptical public that trillions of dollars must be spent on fighting global warming.

The third and most comprehensive investigation into the emails, led by former civil servant Muir Russell, defended the integrity of the university's Climatic Research Unit.

It also said the emails contained nothing to overturn the case for manmade global warming put forward by the United Nations' Intergovernmental Panel on Climate Change (IPCC).

Their rigor and honesty as scientists are not in doubt, the report concluded. We did not find any evidence of behavior that might undermine the conclusions of the IPCC.

However, the scientists were criticized for failing to respond openly to questions about climate data lodged under Britain's freedom of information laws.

We found a tendency to answer the wrong question or to give a partial answer, the report said. Other emails were deleted in anticipation of requests for their release.

Two of the most contentious parts of the emails were the phrases hide the decline and trick, seen as evidence of an attempt to massage data to support the scientists' views.

With reference to hide the decline, the review said the unit's presentation of data was misleading. It said the use of the word trick may have been shorthand for a neat mathematical approach to a problem.

The Internet and blogs have exposed science to unprecedented scrutiny, the report added. Russell said researchers must do more to explain that science can be mired in uncertainty.

The university's vice chancellor, Edward Acton, said the report had exonerated his staff and he hoped it would end the conspiracy theories and untruths that have dogged the unit.

In April, an inquiry into the scientists' actions found no evidence of malpractice, while in March a British parliamentary committee cleared the unit of manipulating the evidence. Police are still investigating the theft of the emails.

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