Researchers from the University of Washington and Columbia University are getting ready for an unprecedented months-long campaign to study Antarctica’s ice shelves from the ocean below, with backing from billionaire philanthropist Paul Allen.
The results are expected to lead to a better understanding of how ice retreats, and how climate change could affect the loss of polar ice sheets and the resulting rise in sea levels.
It’s a high-risk mission — but in this case, robots, not humans, are taking the risk.
“All of these instruments could be lost underneath the ice shelf,” said Spencer Reeder, director of climate and energy for Paul G. Allen Philanthropies.
Reeder said that’s a big reason why Allen, one of Microsoft’s co-founders, is funding the expedition to the tune of just under $2 million. The risks are too high for the traditional funders of polar research, but Allen’s backing could help UW’s Applied Physics Laboratory and College of the Environment prove that their devices can do the job.
“This is part of a series of philanthropic investments that Paul has made, all really focused on this improved understanding of how the Earth is changing, and responding to climate change in particular,” Reeder said.
This week, the UW team is conducting what it expects will be its final round of testing for a fleet of three underwater drones known as Seagliders, plus four profiling floats that are designed to characterize the ocean-ice interface in detail.
Within a couple of months, the battery-powered robots are to be deployed beneath one of West Antarctica’s ice shelves.
Two scientists — UW’s Jason Gobat and Pierre Dutrieux of Columbia University’s Lamont-Doherty Earth Observatory — will oversee the deployment from the R/V Araon, a South Korean icebreaking research vessel, during a voyage that’ll begin a week before Christmas and add up to about 50 days.
“I don’t like to add it up, actually,” Gobat said today during a meeting with journalists aboard the R/V Robertson, a UW research vessel stationed at Seattle’s Shilshole Bay Marina.
Researchers have been using the Robertson as a base of operations for offshore tests of their self-propelled drones and free-floating probes.
UW’s engineers designed the robots to dive hundreds of yards (meters) into the sea to get beneath the ice. They’ve been used successfully to study floating sea ice, but this is the first time they’ll be used to navigate the hazardous twists and turns in underwater caves at the bottom of an Antarctic ice shelf.
The researchers will have to wait until the Korean Polar Research Institute’s icebreaker gets to Antarctica’s Amundsen Sea to decide exactly which ice shelf they’ll study. UW’s Knut Christianson said the Pine Island Glacier is preferred, due to its active dynamics, but that area is also riskier because of the recent break-off of a huge iceberg. On-the-scene observations will be required to make the choice.
Once the robots are deployed, they’ll record readings for location and depth, water temperature, salinity and turbulence — and periodically come up to the surface to relay their data back to UW via the Iridium satellite communications network.
Thanks to a network of acoustic navigation beacons, the robots should be able to range as widely as 30 miles (50 kilometers) as they study the physics of the receding polar ice shelves.
Right now, researchers have very little data about the interface between polar ice and the underlying ocean, said Craig Lee, senior principal oceanographer at UW’s Applied Physics Laboratory.
Changes in polar ice sheets tend to be factored into climate models as parameters that merely approximate what will happen, Lee explained. That leads to wide margins of error in estimates for sea-level rise. For example, nine years ago, UW researchers estimated that water levels in Puget Sound could rise anywhere between 6 and 50 inches by the year 2100.
“If we can actually learn more about the processes, we can improve those parameterizations,” Lee said. “The hope is that by doing that, we narrow down the uncertainties and we get better predictions.”
The researchers say there’s a slight chance that the robots could be recovered a year after their deployment. But they freely admit it’s more likely that the drones and the floats — which cost about $100,000 and $30,000 each, respectively — won’t survive their extended undersea mission.
The research team, and Paul Allen’s team, say the effort is nevertheless worth the cost. Just a couple of weeks’ worth of data would be enough to advance the field of climate science, Christianson said.
“If this mission is even slightly successful, the information could be very valuable,” he told GeekWire.