'Conspiracy theories finally laid to rest' by report on leaked climate change emails

Scientists involved in last year's "climategate" leaked emails controversy, which added to scepticism about the science of global warming, were not open enough with their data and unhelpful with requests for information, an independent review of the affair found yesterday.

They and their institution, the University of East Anglia (UEA), did not embrace the "spirit of openness" enshrined in the Freedom of Information Act, according to a long-awaited report into their conduct carried out by a panel of senior academics.

However, the review found that the researchers concerned, led by the Director of UEA's world-renowned Climatic Research Unit (CRU), Professor Phil Jones, could not be faulted for their "rigour and honesty as scientists", and there was no evidence that they had behaved in a way that might undermine the conclusions of the UN's Intergovernmental Panel on Climate Change (IPCC).

Carried out by a team led by Sir Muir Russell, the former Vice-Chancellor of the University of Glasgow, the review – the third official British inquiry into the affair this year – effectively clears those involved of dishonesty and corruption; it absolves them of the allegation made by climate sceptics that they had manipulated both climate data and the scientific peer-review process, to serve their predetermined views that climate change is man-made.

Sir Muir said the allegation that the CRU had "something to hide" and its research into changes in global temperature could not be trusted because the scientists were concealing or manipulating data "does not stand up".

In these conclusions the Russell review is broadly similar to the two previous enquiries, one by the Commons Select Committee on Science and Technology in March and the other from a panel chaired by Lord Oxburgh, former rector of Imperial College London, which reported in April. Both had given votes of confidence in the credibility and integrity of the studies into climate change which the CRU has carried out.

Yesterday Professor Jones, who had been heavily criticised in the controversy and had stood aside from his post while the review was conducted, was reinstated in the CRU in the new position of Director of Research, which UEA stressed was not a demotion, but merely allowed him to concentrate on research while reducing his administrative responsibilities. The UEA Vice-Chancellor, Professor Edward Acton, said Professor Jones had undergone "a terrible ordeal" and felt he had been "wronged and publicly traduced". Professor Jones himself said that he was "extremely relieved" that the review had been completed.

"We have maintained all along that our science is honest and sound and this has been vindicated now by three different independent external bodies," he said. "There are lessons to be learned from this affair and I need time to reflect on them before speaking in public."

Professor Acton said he hoped the report would "finally lay to rest the conspiracy theories, untruths and misunderstandings that have circulated." The Russell review had "exposed as unfounded the overwhelming thrust of the allegations against our science," he said.

Nevertheless, the review's condemnation of the lack of openness at UEA, which was extended to the university's senior management, amounted to "significant criticisms", Sir Muir said, and its practices needed to change, not least in the light of the new ways in which scientific discourse was being conducted, especially in "the blogosphere".

The so-called Climategate affair began last November when more than 1,000 emails and other documents sent and received by CRU staff over more than a decade were hacked from a UEA server and suddenly placed on the internet, where they were widely circulated and publicised by climate- sceptic bloggers.

No-one has ever discovered who did the hacking and a police enquiry into it is continuing, but it is widely believed that it was carried out to serve the climate sceptic cause and specifically to undermine the UN Climate Conference in Copenhagen, which ultimately proved a failure, with nations unable to agree on carbon emission targets.

The publication of the emails and the storm which followed gave the biggest boost yet to the position of these denying that climate change is man-made – at a vital moment. Most concerned Professor Jones and a small number of other leading climate researchers in Britain and the US who, the sceptics claimed, were shown in them as trying to manipulate some data, suppress other data, have their own views included in the IPCC reports at the expense of differing opinions and refuse access to data to climate sceptics.

The crucial significance of Professor Jones and his unit is that the CRU is one of a handful of bodies which has established – and maintains – the global temperature record back to 1850, using data from instrumental measurements and before that by using "proxies" such as the annual growth of tree rings, whose width and density can give an indication of the average temperature of a year. Reconstructions of previous climates and temperatures by the CRU have been used to support the theory that recent decades have proved the hottest for at least 1,000 years and thus to give credence to the idea that recent warming is outside natural variability and thus down to human actions. Climate sceptics have made determined attempts to discredit the CRU construction of the records. In the most notorious and damaging of the emails, Professor Jones writes that he has just concealed an inconvenient piece of data in an important graph for the World Meteorological Organisation (WMO), the fact that the record of temperatures from tree rings, which for a long time followed instrumental temperatures closely, began to diverge from the instrumental temperature record in about 1960 and while thereafter the instrumental record showed temperatures going up, the tree ring record showed them going down.

Professor Jones tells a colleague he has just carried out "a trick" to "hide the decline" in the tree ring data – he has simply removed the descending line and substituted the rising line from the instrumental measurements.

He is slated for this in the Russell review's most damaging comment, which says that the figure supplied for the WMO report was "misleading", a potentially devastating word to use of a senior scientist.

However, another review panel member, Professor Geoffrey Boulton, said there had not been an intention to mislead, as the true position was explained elsewhere in the document, but it should have been explained in the caption to the graph.

Professor Jones is criticised also over unhelpfulness in providing emails to climate sceptics who had put in Freedom of Information Act requests to see them and the committee finds evidence "that emails might have been deleted in order to make them unavailable should a subsequent request be made for them". But members of the review team said they had not asked Professor Jones specifically if had deleted emails in order to prevent them being seen.

The Government's chief scientist Professor Sir John Beddington said last night: "This is the third review to find no evidence of scientific malpractice at the university. The scientific case that climate change represents a major threat to our world and our societies is clear and compelling."

What the five reports said

* House of Commons Science and Technology Committee: no evidence that the work of Professor Phil Jones and the Climatic Research Unit has been undermined, but they could have been more open.

* Lord Oxburgh inquiry into the science: "absolutely no evidence of any impropriety". Could have used better statistical methods and given greater emphasis to uncertainty, but all conclusions were sensible and honest.

* Sir Muir Russell's inquiry into the emails: the argument that the climate scientists had something to hide "does not stand up". No evidence of selective use of data to produce a predetermined outcome. Scientists needed to be more open to scrutiny.

* Two inquiries by the University of Pennsylvania into scientist Michael Mann: the Investigatory Committee determined that Dr Mann did nothing that seriously deviated from accepted practices within the academic community. A previous investigation found him innocent of suppressing data, deleting e-mails, and misusing confidential information.

How the sceptics responded

* Dr Benny Peiser, director of the Global Warming Policy Foundation, a sceptical think-tank, said the report was a "damning indictment of the university's handling of freedom of information requests". He said: "I don't think the university can just claim this is a vindication."

* Andrew Montford, a climate sceptic who is conducting a review of how the three Climategate enquiries were set up and carried out, said the Russell review "has picked up some of our concerns on freedom of information" but had "brushed other issues under the carpet." He said: "Not to ask Professor Jones if he had deliberately deleted emails so they could not be requested is a pretty extraordinary omission."

* David Holland, a retired engineer and climate sceptic who was one of the principal seekers of information from the CRU, said: "When it was set up 20 years ago the IPCC rules required climate science to be assessed on 'a comprehensive, open and transparent basis'. Sir Muir Russell's enquiry has rightly reported that UEA has not lived up to this."