A number of floating ice shelves in Antarctica are at risk of
disappearing entirely in the next 200 years, as global
warming reduces their snow cover, a new study has found.
Their collapse would enhance the discharge of ice into the
oceans and increase the rate at which sea level rises.
Scientists have been observing ice-shelf retreat around the
Antarctic Peninsula since the early 1990s, but a new model
provides for the first time a strong basis for the prediction
of future changes - a major step forward in understanding
future sea-level changes.
A rapid reduction of greenhouse gas emissions could save a
number of these ice shelves, researchers at Utrecht
University and the British Antarctic Survey say in a paper
published yesterday in the Journal of Glaciology.
In 1995 and 2002, two floating ice shelves in the north of
the Antarctic Peninsula - Larsen A and B - suddenly
"This was a spectacular event, especially when you imagine
the size of these ice shelves, which are several hundreds of
metres thick, and have been in place for over 10,000 years,"
said Dr Peter Kuipers Munneke, the paper's lead author.
The team of researchers suspected that the disappearance of
the snow layer on top of the ice shelves could be an
important precursor for shelf collapse.
Their calculations show that many more ice shelves are in
danger of collapse.
"If we continue to burn fossil fuels at the current rate,
almost all ice shelves in the Antarctic Peninsula will be
under threat of collapse in the next 200 years," Dr Kuipers
The study received financial support from the European
Union's four-year ice2sea project.
- Jamie Morton of the New Zealand Herald