Polar ice keeps melting – whichever way you look at it

By Andy Reisinger 15/10/2009

At the risk of banging on and on about it: another research article just out today from the prestigious journal Nature has used satellite-based measurements to show that the thinning of glaciers that are draining the Greenland and key parts of the Antarctic ice sheet is increasingly widespread. A quote from the abstract:

“We find that dynamic thinning of glaciers now reaches all latitudes in Greenland, has intensified on key Antarctic grounding lines, has endured for decades after ice-shelf collapse, penetrates far into the interior of each ice sheet and is spreading as ice shelves thin by ocean-driven melt. […] Our results show that the most profound changes in the ice sheets currently result from glacier dynamics at ocean margins.”

This study, led by scientists from the British Antarctic Survey, nicely complements (if ‘nice’ is the right word for such news) recent results showing that the total mass of both Greenland and Antarctica has been shrinking as a result of ice loss from surface melting and the accelerated flow of glaciers (see the original study and my blog about it).

The widespread and enduring acceleration and thinning of glaciers at all latitudes around Greenland and key parts of Antactica is of major concern, because it suggests that what we are seeing is increasingly unlikely to be only a temporary hickup of the system. The current rates of ice loss would not have to increase by much more before sea level rise will exceed the top end of the figures provided by the last IPCC assessment.