Comment - Energy and Climate Change
Glacier in retreat by David Flint.
by Gael Durand, a glaciologist at Grenoble Alps University, and others
shows that the Pine Island Glacier, one of the largest in the Antarctic, is in "irreversible decline".
The grounding line - the line along which the glacier lifts away from the sea bottom - has receded about six
miles since 2003. But that's just the start according to Durand; the glacier "has started a phase of
self-sustained retreat and will irreversibly continue its decline". This conclusion is based on the use of
three different models by the authors. The authors expect a five-fold increase in the volume of ice lost
from the glacier for the period 2012 to 2031.
This is dramatic but unsurprising. The
multiple measures of accelerating change:
- The global mean sea level rose by an average of 1.7 mm per year from 1901-2010 but by 3.2 mm per year
between 1993 and 2010.
- Losses from Greenland's ice sheet have probably increased from 34 billion tons per year between 1992 and
2001 to 215 billion tons per year between 2001 and 2010.
- In Antarctica, the rate of loss probably increased from 30 billion tons a year to 147 billion tons a
year over the same timescale.
Forecasts of future warming, melting and sea level rise are highly uncertain precisely because the rates are
increasing so sharply. It's no secret that scientists are struggling to understand these changes. What's not
uncertain is that rising sea levels will threaten low-lying communities round the world, starting with the
poorest. Without radical change in industry and agriculture the question is not whether they will threaten
London but when.
First published in the EGP members newsletter, February 2014
Published and promoted
by Bill Linton for Enfield Green Party, both at 39A Fox Lane, London N13