Experts split over danger to Antarctica
ROBIN MCKIE
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Antarctica drives the globe's weather systems
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— Photo: AFP
COLD FACT: In just over a month an entire Antarctic ice shelf, just over 1,000 square miles, had disappeared.
SERIOUS DISAGREEMENT has broken out among scientists over a United Nations climate report's contention that the world's greatest wilderness — Antarctica — will be largely unaffected by rising world temperatures.
The report, to be published on February 2, will be one of the most comprehensive on climate change to date, and will paint a grim picture of future changes to the planet's weather patterns. However, many researchers believe it does not go far enough.
Severe impact
In particular, they say it fails to stress that climate change is already having a severe impact on the continent and will continue to do so for the rest of the century.
At least a quarter of the sea ice around Antarctica will disappear in that time, say the critics, though this forecast is not mentioned in the study.
One expert denounced the report — by the UN's Intergovernmental Panel on Climate Change, or IPCC — as `misleading'. Another accused the panel of `failing to give the right impression' about the impact of rising levels of CO{-2}.
If all its ice were to melt, sea levels round the world would rise by 70 metres. The fate of that continent crucially affects the fate of the planet, and according to scientists at the British Antarctic Survey it is already being affected by global warming.
"The greatest temperature rise on Earth over the past five decades has been found on the Antarctic peninsula, which stretches north from the continent towards South America," said Dr John Turner. "Temperatures have risen 5 degrees C on the peninsula."
That figure is 10 times the average global temperature rise for the same period.
Humans' role
In addition, researchers reported last October that in just over a month, an entire Antarctic ice shelf, just over 1,000 square miles, had disintegrated and disappeared, with its loss directly linked to man-made global warming.
Yet there is no mention of these events in the draft version of the panel's report obtained by this newspaper.
It paints a broad picture of how carbon emissions will alter global temperatures, which will rise by between 3 degrees C to 5 degrees C by the end of the century. But when it comes to certain types of climate change, especially those concerned with Antarctica, the report is fairly coy.
`Current global studies project the Antarctic ice sheet will remain too cold for widespread surface melting and is expected to gain in mass due to increased snowfall,' states the draft version of the report.
But this vision is disputed. Last year, Dr Turner and colleagues, using records returned by Russian research balloons that were flown over the whole of Antarctica between 1971 and 2003, discovered that temperatures in the lowest level of the atmosphere over the continent have already risen by about 0.7 degree C.
Other factors — including the expected disappearance of the Antarctic ozone hole, which has had a cooling effect — will lead to a further rise of 5 degrees C-6 degrees C over parts of the continent over the rest of the century.
Conservative body
Critics point out that the IPCC is a conservative body whose documents are a co-operative effort, with contributions from hundreds of scientists. Only points that are considered indisputable by all of them are included.
This consensus deflects potential accusations that the body might be exaggerating the threat to the planet. But critics say it also means its documents tend to err too much on the side of caution.
"Parts of the continents are already losing substantial amounts of ice and others will in future — and that will have direct consequences for the rest of the planet," said Dr Chris Rapley, director of the British Antarctic Survey.
@Guardian Newspapers Limited 2007
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