A flotilla of seals will be recruited to take part in an ambitious attempt to study one of the most important glaciers in Antarctica which is melting so fast that it has become the single biggest glacial contributor to global sea-level rise.
The Pine Island Glacier on the West Antarctic Ice Sheet is losing ice at a far faster rate than it is being replenished, and scientists from the British Antarctic Survey (BAS) in Cambridge want to know why it is disappearing to quickly.
They aim to study it with the help of small removable instruments attached to wild seals which swim around and underneath the glacier when foraging for food. In addition the glacier will be monitored from space and by radar, seismic and other scientific instruments dropped from aircraft into the fast-moving ice.
The £7.4m iSTAR research programme, funded by the Natural Environment Research Council, will investigate the stability of the entire West Antarctic Ice Sheet, including the use of temperature and salinity sensors glued temporarily to the backs of elephant seals, which will lose the devices after a year as they moult.
The Pine Island Glacier is the most rapidly changing part of the ice sheet, thinning at a rate of 1 metre a year and with a flow rate to the ocean that has accelerated over the past 15 years, scientists said.
The glacier on its own has contributed to between 1mm and 2.5mm to global sea levels over the past decade, which is currently rising by about 3.2mm a year due to both melting ice and thermal expansion of the oceans.
“We used to think that the volume of water flowing from Antarctica’s melting glaciers and icebergs into the ocean was equal to the amount of water falling as snow onto the ice sheet and that this process was keeping the whole system in balance,” said Andy Smith, science programme manager on ISTAR.
“But Pine Island and Thwaites glaciers on the West Antarctic Ice Sheet are losing ice at a faster rate than they are being replenished. This affects sea level all over the world,” Dr Smith said.
“The speed of changes to this region has taken scientists by surprise and we need to find out what’s going on,” he said.
The iSTAR programme will begin this November and will involve about 35 scientists traveling for 10 weeks over 600 miles of ice sheet using a convoy of specially adapted snow tractors.