Robots, seal-mounted instruments and remote-operated subs part of ambitious project to study Pine Island, Thaite glaciers
By Summit Voice
FRISCO — With this year’s Antarctic research season starting to ramp up, a key focus is taking a closer look at ice sheets on the western side of the continent, where rapid ice loss from the Pine Island and Thwaite glaciers could affect sea level worldwide.
A team of researchers led by the British Antarctic Survey aims to discover what’s causing the recent rapid ice loss, and whether this loss will continue to increase or slow down.
“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 Dr. Andy Smith, British Antarctic Survey, science program manager for the NERC-funded iSTAR programme. “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. The speed of changes to this region has taken scientists by surprise and we need to find out what’s going on,” Smith said.
The first group of scientists will spend 10 weeks traveling 600 miles across the ice sheet by tractor-traverse, using ground-based radar and seismic technologies to map the bed beneath Pine Island Glacier. The research may help show how glacier bed conditions affect the flow and thickness of ice all the way from the floating shelf up into its inland tributaries. Satellite remote sensing technology will allow the science team to measure the changing configuration of the glacier in areas that are inaccessible from the ground.
In January 2014, a team will sail into the Amundsen Sea aboard the RRS James Clark Ross to spend 30 days putting a range of instruments and devices into the ocean near Pine Island Glacier to discover when, where, and how warm ocean water gets close to the ice. Ocean measurements and observations are essential for improving a wide variety of computer models used by the international scientific community to forecast future climate and sea level.
A fleet of ocean robots known as Seagliders will measure the temperature, saltiness and current speeds at different depths in the water. Each time the Seaglider reaches the ocean surface it will send back data using satellite phone technology. The scientists will use the information from Seagliders to work out how the warm water is reaching the ice shelf and whether this is likely to continue in future.
To collect data during the Antarctic winter, when the ocean surface is covered by sea ice and inaccessible for research ships, the team is enlisting the help of 15 seals. Small sensors, temporarily glued to their fur, will capture information such as the temperature and the saltiness. Satellite technology will send information back to the scientists in their laboratories. This research also provides biologists with a better indication of how vulnerable seals might be to climate change. The sensors fall off when the seals moult their fur.
An unmanned submarine (Autosub1), capable of diving beneath the ice, will make measurements along a pre-defined track then return to the ship with the data. To understand the rate at which the thickness of the ice changes four autonomous radar instruments, engineered to allow year-round operation, will monitor the gradual change of ice shelf thickness with time. This investigation will help the science team determine how heat is transported beneath the ice shelf by ocean currents and what impact changes in the climate will have on this part of Antarctica.
“We are attempting to tackle this big science question from a number of different ice and ocean perspectives,” said UEA’s Professor Karen Heywood. “Our observations and measurements will be a major contribution to the on-going, and urgent, international scientific effort to understand our changing world.”