A New Zealand scientist has been caught up in an international computer hacking stunt in which thousands of climate change documents and private emails have been leaked on the internet.

Climate scientist Jim Salinger is among the many who have had private emails and documents posted on a blogsite, after computer hackers apparently infiltrated a research centre at the University of East Anglia in Britain.

Dr Salinger's emails, which date from the middle of this year, form part of an exchange between a number of climate experts on how to respond to a paper by Auckland University scientist Chris de Freitas and two others.

That paper - published in the Journal of Geophysical Research - claimed the el nino and la nina weather patterns were a dominant influence on climate change.

In one July email, Dr Salinger reacts to the de Freitas paper: "Is there an opportunity to write a letter to JGR pointing out the junk science in this?? ... If it is not rebutted, then all sceptics will use this to justify their position."

The group went on to co-author a response to the paper.

Dr Salinger said last night that the emails had been taken "completely and unfairly out of context".

"As scientists we are always debating and discussing. These are just normal discussions between colleagues - just like you emailing your friends. To take an email out of context is very dishonest.

"They're also trying to ruinpeople's credibility and I think that's disgusting," Dr Salinger said.

Dr de Freitas is an associate professor at the School of Geography, Geology and Environmental Science, and a well-known sceptic about manmade global warming. He could not be contacted last night, but told the Epoch Times he considered the emails "quite revealing".

"I think it's serious because there have been many different people claiming the so-called 'objective experts' have been not totally 100 per cent with their claims, and certainly the data they have used to back up their claims."

Another climate change scientist whose private emails were hacked believes the leaks may have been aimed at undermining next month's global climate summit in Denmark.

Kevin Trenberth, of the US National Centre for Atmospheric Research, said the hackers distributed only those documents that could help attempts by sceptics to undermine the scientific consensus on manmade climate change.

The respected atmospheric scientist said it did not appear that all the documents had been distributed.

About 1000 emails and 3000 documents have been posted on websites and seized on by climate change sceptics, who claim correspondence shows collusion between scientists to overstate the case for global warming, and evidence that some have manipulated evidence.

At least 65 world leaders will attend the Copenhagen climate summit, where representatives of 191 nations will seek agreement on a new global treaty on limiting emissions of greenhouse gases.