The University of East Anglia Climatic Research Unit, which was at the centre of the 'Climategate' controversy, has released almost all the data it has received on temperature changes around the globe.

The Norwich-based unit has released data provided by Trinidad and Tobago, against that state's wishes, but information from 19 stations in Poland has been withheld.

It comes after Freedom Of Information requests were submitted following the Climategate controversy of 2009, when climate sceptics claimed leaked documents from the unit showed data had been manipulated in favour of man-made climate change.

Phil Jones, director of the Climatic Research Unit, was subsequently cleared by a committee of MPs of hiding or manipulating data to back up his own science.

But the unit was criticised by an independent report for not having been open or transparent enough and has now made more data available.

Some countries' meteorological services, including Poland's, had been unwilling to have their data publicly released – some, who charge for this information, for commercial reasons.

The university released data from Trinidad and Tobago despite the state's wishes because the Information Commissioner Officer instructed them to release part of the database which covered the latitude zones 30� N to 40� S.

Professor Trevor Davies, UEA pro-vice-chancellor for research, said: 'We regret having to release data from Trinidad and Tobago against that state's express wish but we want to place beyond all doubt our determination to be open with our data and to comply with the ICO's instruction.

'To demonstrate that determination we have made the decision, in discussion with the Met Office, to release the data from latitudes outside the 30� N to 40� S zone, with the exception of some stations in Poland which has explicitly refused permission. This means that data from 5113 weather stations around the world are now released.

'We are very pleased to be in the position now to release data for all but 19 stations and are grateful to the Met Office for its support over the past 18 months and for its major effort in contacting National Meteorological Services to seek their permission for release.

'In the interest of openness, we have released data from those which have not responded to requests to release.

'We remain concerned, however, that the forced release of material from a source which has explicitly refused to give permission for release could have some damaging consequences for the UK in international research collaborations.'