SCIENTISTS at the University of East Anglia (UEA) have admitted throwing away much of the raw temperature data on which their predictions of global warming are based.

It means that other academics are not able to check basic calculations said to show a long-term rise in temperature over the past 150 years.

The UEA’s Climatic Research Unit (CRU) was forced to reveal the loss following requests for the data under Freedom of Information legislation.

The data were gathered from weather stations around the world and then adjusted to take account of variables in the way they were collected. The revised figures were kept, but the originals — stored on paper and magnetic tape — were dumped to save space when the CRU moved to a new building

The admission follows the leaking of a thousand private emails sent and received by Professor Phil Jones, the CRU’s director. In them he discusses thwarting climate sceptics seeking access to such data.

In a statement on its website, the CRU said: “We do not hold the original raw data but only the value-added (quality controlled and homogenised) data.”

The CRU is the world’s leading centre for reconstructing past climate and temperatures. Climate change sceptics have long been keen to examine exactly how its data were compiled. That is now impossible.

Roger Pielke, professor of environmental studies at Colorado University, discovered data had been lost when he asked for original records. “The CRU is basically saying, ‘Trust us’. So much for settling questions and resolving debates with science,” he said.

Jones was not in charge of the CRU when the data were thrown away in the 1980s, a time when climate change was seen as a less pressing issue. The lost material was used to build the databases that have been his life’s work, showing how the world has warmed by 0.8C over the past 157 years.

He and his colleagues say this temperature rise is “unequivocally” linked to greenhouse gas emissions generated by humans. Their findings are one of the main pieces of evidence used by the Intergovernmental Panel on Climate Change, which says global warming is a threat to humanity.

http://www.timesonline.co.uk/tol/news/environment/article6936328.ece