Bridging the gap
NASA in second year of airborne campaign to monitor Antarctic ice
Posted November 5, 2010
Scientists returned to the skies above Antarctica in October for the second year of NASA’s Operation IceBridge . The airborne mission monitors the region’s changing sea ice, ice sheets and glaciers using radar and other instruments flown aboard a specially outfitted DC-8.
The six-year program is intended to bridge the gap between the loss of NASA’s Ice, Cloud and land Elevation Satellite (ICESat) in 2009 and the launch of a new ICESat in 2015. The satellite transmitted data on conditions of sea ice, glaciers, ice sheets and ice shelves, helping scientists study changes to these features in three dimensions.
IceBridge researchers will make flights from Punta Arenas, Chile, to re-survey areas that are undergoing rapid change, mostly in West Antarctica, and to embark on new lines of investigation.
The Antarctic campaign is scheduled to last until mid-November. IceBridge began in 2009, with mission scientists and crew participating in 41 flights and collecting data over about 143,000 miles so far over the Arctic and Antarctic.
“We are excited to learn how the glaciers and sea ice have changed since last year’s campaign,” said Michael Studinger , IceBridge project scientist at NASA’s Goddard Space Flight Center in Greenbelt, Md., in a press release from NASA.
“We also are going to be mapping uncharted regions that will allow us to better assess future behavior of the Antarctic ice sheets and sea ice,” he added.
Instruments for the 2010 Antarctic campaign are the same as those flown in 2009. A laser instrument will map and identify surface changes. Radar instruments will penetrate the snow and ice to see below the surface, providing a profile of ice characteristics and also the shape of the bedrock supporting it. A gravity instrument will measure the shape of seawater-filled cavities at the edge of some major fast-moving glaciers.
Several radars used in IceBridge were developed by the Center for Remote Sensing of Ice Sheets (CReSIS) at the University of Kansas , a National Science Foundation (NSF) -funded Science and Technology Center.
Pine Island Glacier, the largest glacier in West Antarctica with significant potential to contribute to sea-level rise, has long been a primary target for sustained observations. NSF-funded scientists preparing to deploy instruments underneath the ice shelf that fronts the glacier are using data from IceBridge to help plan their field campaign, which begins in 2011-12. [See related story: Cracking the case.]
Photo Credit: Kyle Krabill, ATM Instrument Team Engineer, NASA's Wallops Flight Facility
NASA's DC8, a flying laboratory, takes off from Punta Arenas, Chile.
In addition to flying previous lines over the glacier, the IceBridge team plans to fly a new horseshoe pattern to sample the tributaries feeding into Pine Island Glacier’s main trunk. Other new flight lines will further explore the Antarctic Peninsula to map new targets, including the George VI Ice Shelf, above and below the ice.
Three high-priority flights are aimed at measuring sea ice, including a plan to map and measure sea ice across the Weddell Sea. Scientists want to know why sea ice in Antarctica is growing in extent, unlike sea ice in the Arctic, which is shrinking. The northwestern region of the peninsula is the exception, with sea ice duration is decreasing substantially. [See IceBridge blog for more information.]
Other flights are planned to be coordinated with existing space- and ground-based missions, such as the European Space Agency’s ice-observing Cryosat-2 satellite and European ship-based research. Overlapping measurements help researchers calibrate instruments and boost confidence in the resulting observations.
“A concerted effort like this will allow us to produce long time series of data spanning from past satellite missions to current and future missions,” Studinger said. “This is only possible through international collaboration. We are excited to have many opportunities to work with our international partners during the upcoming campaign.”