Two sections of the Larsen ice shelf collapsed in 1995 and 2002.
Now satellite measurements have confirmed that it has thinned by
as much as 18 metres more than usual in the past decade, because
of a warmer ocean. The report comes a day after a University
College London report in the journal Nature confirmed a 40%
thinning of the ice in the Arctic Ocean in the past 30 years.
Andrew Shepherd of Cambridge University and colleagues from
University College London, Bristol, and the Antarctic Institute
of Argentina, report in the journal Science that they have been
mapping changes in the Larsen shelf, on the east of the
Antarctica peninsula, since 1992. The shelf covers approximately
27,000 sq miles and is on average 300 metres deep. Its faster
rate of melting is releasing an extra 21bn tonnes of icy water
into the oceans each year. This is equivalent to eight times the
annual flow of the river Thames. Warmer oceans, as well as
warmer air, are now thought to play an important part in the
process. The scientists use