COPENHAGEN - The head of the U.N.'s panel of climate scientists on Monday strongly defended findings that humans are warming the planet, after critics said that leaked emails from a British university had undermined evidence.

Rajendra Pachauri, head of the U.N.'s Intergovernmental Panel on Climate Change (IPCC), told a climate conference that its findings were subjected to extensive and repeated reviews by experts as well as by governments.

The IPCC concluded in 2007 that it was at least 90 percent certain that humans were to blame for global warming.

But climate change sceptics have seized on a series of hacked emails written by climate specialists, accusing them of colluding to suppress others' data and enhance their own.

The evidence is now overwhelming that the world would benefit greatly from early action, Pachauri told delegates at the opening session of the December 7-18 Copenhagen summit.

The recent incident of stealing the emails of scientists at the University of East Anglia shows that some (people) would go to the extent of carrying out illegal acts perhaps in an attempt to discredit the IPCC.

The emails, some written as long as 13 years ago, were stolen by unknown hackers and spread rapidly across the Internet. Sceptics say that the emails showed that scientists had manipulated evidence.

In one email, confirmed by the University of East Anglia as genuine, the head of its Climatic Research Unit (CRU), Phil Jones, said he wanted to ensure a specific paper which doubted climate science was excluded from the IPCC's 2007 report.

That paper did in fact appear in the final 2007 report, the university says. Pachauri on Monday defended scientists named in the climategate row.

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, Pachauri told the 192-nation conference.

Given the wide-ranging nature of (economic) change that is likely be taken in hand, some naturally find it inconvenient to accept its inevitability.

NOT TRUE

Saudi Arabia, the world's biggest oil exporter, told conference delegates that the row would impact the Copenhagen talks and belief in climate science.

The level of confidence is certainly shaken. We believe this scandal is definitely going to affect the nature of what can be fostered (in Copenhagen). The size of (economic) sacrifices must be built on a secure foundation of information which we found now is not true, a Saudi delegate said.

Another British climate research center, the MetOffice Hadley Center, plans to publish this week data from more than 1,000 locations around the world to boost transparency and underpin evidence that the world is warming.

We are confident (it) will show that global average temperatures have risen over the last 150 years, it said in a statement, adding that the move had the support of the University of East Anglia.

As soon as we have all permissions in place we will release the remaining station records.

(Editing by Dominic Evans)

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