Al Gore's Oscar-winning documentary on global warming, An Inconvenient Truth, was yesterday criticised by a high court judge who highlighted what he said were "nine scientific errors" in the film.

Mr Justice Barton yesterday said that while the film was "broadly accurate" in its presentation of climate change, he identified nine significant errors in the film, some of which, he said, had arisen in "the context of alarmism and exaggeration" to support the former US vice-president's views on climate change.

The film was broadly welcomed by environmental campaigners and scientists on its release last year, and while they did point out that it contained mistakes, these were relatively small and did not detract from the film's central message - that global warming was a real problem and humans had the technology to do something about it.

The judge made his remarks when assessing a case brought by Stewart Dimmock, a Kent school governor and a member of a political group, the New party, who is opposed to a government plan to show the film in secondary schools.

The judge ruled that the film can still be shown in schools, as part of a climate change resources pack, but only if it is accompanied by fresh guidance notes to balance Mr Gore's "one-sided" views. The "apocalyptic vision" presented in the film was not an impartial analysis of the science of climate change, he said.

The judge also said it might be necessary for the Department of Children, Schools and Families to make clear to teachers some of Mr Gore's views were not supported or promoted by the government, and there was "a view to the contrary".

He said he had viewed the film and described it as "powerful, dramatically presented and highly professionally produced", built around the "charismatic presence" of Mr Gore, "whose crusade it now is to persuade the world of the dangers of climate change".

The mistakes identified mainly deal with the predicted impacts of climate change, and include Mr Gore's claims that a sea-level rise of up to 20ft would be caused by melting in either west Antarctica or Greenland "in the near future".

The judge said: "This is distinctly alarmist and part of Mr Gore's 'wake-up call'." He accepted that melting of the ice would release this amount of water - "but only after, and over, millennia."

Despite his finding of significant errors, Mr Justice Barton said many of the claims made by the film were supported by the weight of scientific evidence and he identified four main hypotheses, each of which is very well supported "by research published in respected, peer-reviewed journals and accords with the latest conclusions of the IPCC [Intergovernmental Panel on Climate Change]."

The nine points: fact or fallacy?

· The film claimed that low-lying inhabited Pacific atolls "are being inundated because of anthropogenic global warming" - but there was no evidence of any evacuation occurring

· It spoke of global warming "shutting down the ocean conveyor" - the process by which the gulf stream is carried over the north Atlantic to western Europe. The judge said that, according to the Intergovernmental Panel on Climate Change, it was "very unlikely" that the conveyor would shut down in the future, though it might slow down

· Mr Gore had also claimed - by ridiculing the opposite view - that two graphs, one plotting a rise in C02 and the other the rise in temperature over a period of 650,000 years, showed "an exact fit". The judge said although scientists agreed there was a connection, "the two graphs do not establish what Mr Gore asserts"

· Mr Gore said the disappearance of snow on Mt Kilimanjaro was expressly attributable to human-induced climate change. The judge said the consensus was that that could not be established

· The drying up of Lake Chad was used as an example of global warming. The judge said: "It is apparently considered to be more likely to result from ... population increase, over-grazing and regional climate variability"

· Mr Gore ascribed Hurricane Katrina to global warming, but there was "insufficient evidence to show that"

· Mr Gore also referred to a study showing that polar bears were being found that had drowned "swimming long distances to find the ice". The judge said: "The only scientific study that either side before me can find is one which indicates that four polar bears have recently been found drowned because of a storm"

· The film said that coral reefs all over the world were bleaching because of global warming and other factors. The judge said separating the impacts of stresses due to climate change from other stresses, such as over-fishing, and pollution, was difficult

· The film said a sea-level rise of up to 20ft would be caused by melting of either west Antarctica or Greenland in the near future; the judge ruled that this was "distinctly alarmist"

· This article was amended on Friday October 12 2007. A panel in the article above listing the significant errors found by a high court judge in Al Gore's documentary on global warming was labelled The nine points, but contained only eight. The point we omitted was that the film said a sea-level rise of up to 20ft would be caused by melting of either west Antarctica or Greenland in the near future; the judge ruled that this was "distinctly alarmist". The missing point has been added.