The National, Friday 17th August 2012
ARCTIC sea ice is melting at a faster rate than previously believed, a group of scientists have claimed.
The European Space Agency say that new satellites they are using have revealed that 900 cubic kilometres of ice have disappeared over the last year.
This is 50 per cent higher than the current estimates from environmentalists, they claim.
It is suggested that the increase is down to global warming and rising greenhouse gas emissions.
The entire region could be eventually free of ice if the estimates prove accurate. This would trigger a “gold rush” for oil reserves and fish stocks in the region.
“Preliminary analysis of our data indicates that the rate of loss of sea ice volume in sum¬mer in the Arctic may be far larger than we had previously suspected,” said Dr Seymour Laxon, of the Centre for Polar Observation and Modelling at University College London (UCL), where CryoSat-2 data is being anal¬ysed, told the Observer.
The scientists launched the CryoSat-2 probe in 2010 specifically to study ice thickness. Until then most studies had focused on the coverage of the ice.
Submarines were also sent into the water to analyse the ice. The methods are said to have given a picture of changes in the ice around the north pole since 2004.
The study revealed that the depth of ice had also been decreasing in addition to the amount of sea it stretched across.
Data from the exploration shows that in winter 2004, the volume of sea ice in the cen¬tral Arctic was approximately 17,000 cubic km. This winter it was 14,000 km, according to CryoSat.
The amount of ice in summer 2004 was said to be 13,000 km and not it is 7,000.
Professor Chris Rapley of UCL added: “Before CryoSat, we could see summer ice coverage was dropping markedly in the Arctic.
“But we only had glimpses of what was happening to ice thickness. Obviously if it was dropping as well, the loss of summer ice was even more significant.”
The findings come after study released earlier this month from the University of Copenhagen claimed that Greenland’s ice is less vulnerable than feared to a runaway melt that would drive up world sea levels.
“It is too early to proclaim the ‘ice sheet’s future doom’ caused by climate change”, lead author Kurt Kjaer wrote in a statement of the findings in the journal Science.
An examination of old photos taken from planes revealed a sharp thinning of glaciers in north-west Greenland from 1985 to 1993, the experts in Denmark, Britain and the Netherlands wrote.
Another pulse of ice loss in the area lasted from 2005 to 2010.
The discovery of fluctuations casts doubt on projections that Greenland could be headed for an unstoppable meltdown, triggered by manmade global warming.
Greenland contains enough ice to raise sea levels by 7 metres (23 ft) if it all thawed.
“It starts and then it stops,” Kjaer said of the ice losses.
“This is a break from thinking that it is something that starts, accelerates and will consume Greenland all at once.”
However, Kjaer noted that the ice sheet did not get bigger in the pause between the pulses of ice loss.
He said satellite data of Greenland’s ice only dated back to about 2000 and the use of aerial photos had extended the records of the remote Arctic region back another 15 years.-Mail Online