The head of the research unit at the centre of the "Climategate" row over global warming science admitted to MPs yesterday that he had not released data about his work because it was not standard practice to do so.
Phil Jones, director of the University of East Anglia's Climatic Research Unit (CRU), told the Science and Technology Committee that the centre withheld raw station data about global temperatures from around the world - but said that the same information was publicly available in the US.
And he said it was not "standard practice" in climate science to release data and methodology for scientific findings so that other scientists could check and challenge the research.
He also said the scientific journals which had published his papers had never asked to see it.
The world-renowned research unit has been under fire since private e-mails, which sceptics claimed showed evidence of scientists manipulating climate data, were hacked from the university's server and posted online.
Appearing before the committee's hearing into the disclosure of data from the CRU alongside Prof. Jones, the university's vice chancellor Edward Acton said he had not seen any evidence of flaws in the overall science of climate change - but said he was planning this week to announce the chair of a second independent inquiry, which will look into the science produced at CRU.
A first independent probe is examining allegations stemming from the e-mails that scientists hid, manipulated or deleted data to exaggerate the case for manmade global warming.
Challenged about one e-mail in which he tells a sceptic he does not want to give him data because it will be misused, Prof. Jones admitted: "I have obviously written some pretty awful e-mails".
But Prof. Jones insisted the scientific findings on climate change were robust and verifiable.
And he said 80 per cent of the raw data used to create a series of average global temperatures showing that the world was getting warmer, along with methodology from the Met Office - but not CRU - on how the average temperatures were calculated, had been released.
According to the University of East Anglia (UEA) much of the data could not have been released without the permission of the countries which generated the information - and that while the majority had now allowed the figures to be released, a handful had refused to let CRU publish it.
Prof. Jones said a "deluge" of Freedom of Information requests last July had prompted the unit - which has only three full time staff - to try and get more of the data released.
The university disputes suggestions from the Information Commissioner's Office that CRU had breached Freedom of Information rules, based on emails which talk about deleting data, but could not be investigated because too much time had elapsed.
The committee quizzed former information commissioner Richard Thomas, who said there were exemptions to the law on releasing information if the data had been received from a third party, with whom there was an agreement not to disclose it and who was not subject to FOI rules, which would cover the station data from other countries' meteorological services.
But while he said he understood the "human dimension" of frustration with a significant increase in FOI requests - such as the increase from a handful of queries to more than 60 which the CRU experienced last year - he said the law gave people a right to know and the simplest approach was "proactive" disclosure of information.
Prof. Acton said he believed the university should go "well beyond" FOI requests in disclosing data because the issue was so important that once people imagined there was a conspiracy, any failure to release information would feed that belief.
Defending the research unit, he pointed out that Prof Jones had 450 co-authors on papers from 100 universities including Harvard, Yale, Oxford and Imperial College London.
Earlier, the committee heard from Lord Lawson, a sceptic who chairs the Global Warming Policy Foundation think tank, who claimed that Freedom of Information Act requests should not have been necessary because "proper scientists, scientists of integrity reveal voluntarily all their data".
Lord Lawson declined to reveal who funds his think-tank, but insisted it did not take money from the energy industry.
Giving evidence to the committee, he raised concerns about the impartiality of members of the independent inquiry into the emails affair, and into one particular email which talks about a "trick" to "hide the decline" in temperatures suggested by tree ring data from the 1960s which does not match actual temperature records.
He said the decline undermined the reliability of so-called paleoclimatic data which is used to estimate temperatures before instrumental records began, and criticised the "procedure" used to hide it.