The NASA P-3 leaving the hangar at Wallops Flight
Facility in Virginia on the morning of March 10 in preparation for the flight to
Thule Air Base, Greenland.
Image Credit: NASA/Patrick Black
Researchers aboard NASA's P-3 research aircraft left the agency's Wallops
Flight Facility in Wallops Island, Va., March 10 for Greenland to begin a new
season of collecting data on Arctic land and sea ice.
The mission, known as Operation IceBridge, is to gather data on changes to
polar ice and maintain continuity of measurements between NASA's Ice, Cloud and
Land Elevation Satellite (ICESat) missions. The original ICESat mission ended in
2009, and its successor, ICESat-2, is scheduled for launch in 2017.
By flying yearly campaigns, IceBridge provides valuable data on rapidly
changing areas of polar land and sea ice. Flights run through May 23 from Thule
Air Base and Kangerlussuaq, Greenland, with a week-long deployment to Fairbanks,
Alaska.
Five new NASA Earth science missions are launching
in 2014 to expand our understanding of Earth’s changing climate and
environment.
Over the past five years, IceBridge has surveyed large portions of the
Greenland and Antarctic ice sheets, as well as sea ice in both polar regions.
IceBridge data have been used to build detailed maps of bedrock in Greenland and
Antarctica, calculate changes in Arctic sea ice thickness and volume, and
improve our understanding of the rate at which glaciers in Greenland are flowing
into the sea.
The first part of the campaign will focus on sea ice in the Arctic Ocean
north of Greenland and in the Beaufort and Chukchi seas north of Alaska. As in
the past two years, IceBridge will provide data on ice thickness to help sea ice
researchers develop more accurate seasonal Arctic sea ice models.
The remainder of the campaign will turn to measuring ice surface elevation
and thickness at many of the Greenland Ice Sheet's outlet glaciers, which are
channels of ice that flow from an ice sheet, constrained on its sides by
bedrock. The surface elevation measurements taken by IceBridge's laser
altimeter, the Airborne Topographic Mapper, will provide scientists data on how
the ice sheet is changing and give a useful benchmark for ICESat-2.
Radar instruments such as the Multichannel Coherent Radar Depth Sounder,
which is operated by the Center for Remote Sensing of Ice Sheets at the
University of Kansas in Lawrence, Kan., will peer beneath the surface to collect
the data on ice thickness and sub-ice terrain, internal layering in the ice
sheet and snow depth.
The P-3 research aircraft's extensive instrument suite features a new
component this year –
a spectrometer that measures ice albedo, or reflectivity.
a spectrometer that measures ice albedo, or reflectivity.
"A small change in albedo over the entire Arctic could have a significant
effect on how much heat is absorbed by the surface," said Nathan Kurtz, a sea
ice scientist at NASA's Goddard Space Flight Center in Greenbelt, Md. This
year's flights will serve as a preliminary test for the instrument.
Throughout the campaign, the IceBridge team will coordinate its efforts with
other research groups working in the region. Researchers on the surface will
study sea ice and snow thickness near Barrow, Alaska, in the Canadian Basin and
just north of Greenland. Measurements in these areas will later be used to
further verify the accuracy of IceBridge's snow radar instrument, particularly
in areas with rough ice surfaces.
Panoramic view of Thule Air Base, Greenland, on
Mar. 10, 2014.
Image Credit: NASA / Christy Hansen
According to Jackie Richter-Menge, sea ice scientist with the U.S. Army Corps
of Engineers Cold Regions Research and Engineering Laboratory in Hanover, N.H.,
snow radar works well on ice that has not been deformed. Ice with a rougher
surface can scatter radar waves, making the returning signal harder to
interpret.
The IceBridge team also will work with the CryoVEx (CryoSat-2 Validation
Experiment) team, which operates a campaign to verify measurements made by the
European Space Agency's ice-monitoring satellite, CryoSat-2, in orbit since
2010. The IceBridge team plans to fly directly beneath the orbit of CryoSat-2
around the same time the satellite passes overhead to compare measurements.
Researchers from the European Space Agency, York University in Toronto, Canada,
and the Technical University of Denmark also will be flying airborne instruments
to measure ice and snow.
"It's really exciting to have all of these people working together," said
Richter-Menge. "It shows how interested everyone is in advancing these
measurements."
Three high school science teachers from the United States, Denmark and
Greenland also will join IceBridge and fly with the team to get first-hand
experience and knowledge they can bring back to their classrooms. These teachers
come to IceBridge through partnerships with the U.S.-Denmark-Greenland Joint
Committee and PolarTREC, a U.S.-based program that pairs teachers with polar
research expeditions.
For more about Operation IceBridge and to follow this year's campaign,
visit:
For more about PolarTREC and the IceBridge teacher research experience,
visit:
For more about the U.S.-Denmark-Greenland Joint Committee, visit:
NASA monitors Earth's vital signs from land, air and space with a fleet of
satellites and ambitious airborne and ground-based observation campaigns. NASA
develops new ways to observe and study Earth's interconnected natural systems
with long-term data records and computer analysis tools to better see how our
planet is changing. The agency shares this unique knowledge with the global
community and works with institutions in the United States and around the world
that contribute to understanding and protecting our home planet.
For more information about NASA's Earth science activities in 2014,
visit:
NASA
Guillermo Gonzalo Sánchez Achutegui
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