Arctic Research Vessel Set Adrift to Study Sea Ice Decline
By Suzanne Goldenberg, The Guardian
A research vessel is adrift in the Arctic to study why sea ice is retreating faster than expected.
Ice cover across the northern ocean fell to a new low last month, reaching just over 14.5 million square kilometers (5.61 million square miles) at its winter peak, according to the National Snow and Ice Data Center, in Colorado.
RV Lance on 17 February 2015. Credit: Paul Dodd/Norwegian Polar Institute
That was 130,000 square kilometers (50,193 square miles) smaller than the previous winter low set in 2011 — confounding scientific predictions about the decline of sea ice under climate change.
“We are obviously missing something,” said Harald Steen, a biologist from the Norwegian Polar Institute, and the leader of the international expedition. “We are underestimating the rate of ice disappearance in the north.”
The RV Lance set out on January 11 with 30 scientists and crew, who planned to spend an entire season on the sea ice, from winter freeze to break-up in early summer.
A separate expedition to the high Arctic, using a hovercraft, has spent six months crossing the Lomonosov ridge, a submarine mountain range near the north pole with peaks as high as the Alps.
The researchers on the RV Lance are trying to understand how snow, sea water, wind and ocean currents drive the formation and break-up of younger, thinner sea ice.
For the first six weeks, the RV Lance crew operated in the absolute darkness of the polar night, venturing out at temperatures approaching minus 40°C (-40°F) to explore surrounding ice floes on foot, skis or snowmobiles.
“You have an environment that is pitch dark and it is cold — minus 35, minus 37 — and there is a little bit of wind and it is rather hostile,” Steen said.
Scientists from Norwegian Polar Institute collect zooplankton in front of the RV Lance, March 2015.
Credit: Tor Ivan Karlsen/Norwegian Polar Institute
The ship has got stuck in pack ice on at least two occasions and had to be towed out by the Norwegian coast guard. There were a few close encounters with polar bears.
The scientists rotate through on six-week shifts. The RV Lance will make only occasional use of its engines, Steen said. Otherwise, the ship will just go with the ice floes drifting in a clockwise direction across the ocean at a speed of 0.2 knots: about the pace of a very lazy stroll.
Much remains unknown about the Arctic, about what causes ice to form and break up, and about how the changes in the sea ice affect wider climate system.
Those process have changed over the past three decades as the Arctic experiences warmer temperatures.
Researchers have suggested the decline in sea ice has disrupted the jet stream, and could be responsible for the ferociously cold winters in North America.
The researchers aim to drift at the edge of the ice, tracking the gulf stream and the east Greenland current as they empty into the Arctic, and lowering buoys from the ship to measure ice mass balance, snow and sea water seeping up through cracks in the ice.
Reprinted from The Guardian with permission.