Study confirms Greenland ice sheet melt due to global warming

[Date: 2008-01-16]

 

Global warming is behind the melting of the Greenland ice sheet, new research from an international team of glaciologists and climatologists confirms.

The scientists, from the UK, Belgium, Denmark and the US, arrived at their conclusion after analysing glaciological and meteorological records going back some five decades. Their findings are published in the Journal of Climate.

Their investigations revealed that between the 1960s and 1990s, changes in the Greenland ice sheet were due to regional, rather than global changes in the climate. However, over the past 15 years there has been a statistically significant link between global temperatures and temperatures in Greenland. Over the same time period, levels of ice melting in Greenland increased.

Half of the annual run-off from the ice sheet takes place in July, and the four warmest summers on record were within the last six years. Summer 2003 was exceptionally warm around the edges of the ice sheet, and this led to the second-highest meltwater running off from the ice sheet in the last 50 years. The summer of 2005 broke the melting record, which was broken again in 2007 - a year which was almost as warm as 2003.

'Our statistical analysis suggests that southern Greenland climate is currently responsive to general Northern Hemisphere warming,' the scientists conclude. 'As a consequence, the GrIS [Greenland ice sheet] is likely to be highly susceptible to ongoing global warming, in which Greenland temperatures are predicted to increase ~1° - 8°C by 2100.'

'Our work shows that global warming is beginning to take its toll on the Greenland ice sheet which, as a relict feature of the last Ice Age, has already been living on borrowed time and seems now to be in inexorable decline,' commented Dr Edward Hanna of the University of Sheffield, who led the research. 'The question is can we reduce greenhouse gas emissions in time to make enough of a difference to curb this decay?'

If the Greenland ice cap were to melt entirely, it would cause sea levels to rise by seven metres. Understanding its current situation and response to climate change is therefore extremely important.