Ice cap meltdown to cause 22ft floods
Pastor Dale Morgan
Ice cap meltdown to cause 22ft floods*
Last Updated: 12:01am BST 16/08/2007
The Greenland ice sheet is doomed to melt away within the next three
centuries and flood hundreds of millions of people out of their homes.
This is the stark warning given by a scientist who claims that current
forecasts grossly overestimate how long the ice sheet will survive.
The Intergovernmental Panel on Climate Change (IPCC) has previously
stated that a total meltdown is likely to take at least 1,000 years.
However, Dr Tim Lenton of the University of East Anglia, believes the
risk are far greater than the IPCC suggests.
Speaking at a meeting in Cambridge organised by the British Antarctic
Survey, Dr Lenton said: "We are close to being committed to a collapse
of the Greenland ice sheet. But we don't think we have passed the
tipping point yet."
A remnant of the last Ice Age, Greenland's ice cap is nearly two miles high.
But if the climate change crisis reached the point of no return and it
were to melt then global sea levels would rise by 22ft and swallow up
most of the world's coastal regions.
Dr Lenton's group - whose members include John Schellnhuber, the chief
scientist on climate change at the recent G8 meeting in Germany - also
identified eight environmental "tipping points" that could occur this
century.
These include a collapse of the thermohaline circulation, which is the
name given to a global system of ocean currents. Besides shutting down
the Gulf Stream, this could also "switch off" the Asian monsoon and warm
the Southern Ocean, perhaps destabilising the West Antarctica ice sheet.
Likewise, global warming may cause a near-permanent El Nino in the
Pacific, which would also hasten runaway fires in the Amazon rainforest
and its disappearance by the middle of the century.
Also at the Cambridge meeting Professor Lenny Smith, a statistician at
the London School of Economics, warned about the "naive realism" of
current climate models.
He singled out for criticism the government's UK Climate Impacts
Programme as well as the Met Office.
He accused both of making detailed climate projections for individual
regions when global climate models disagree strongly about how climate
change will affect the British Isles.