Washington, D.C.
— Researchers and flight crew arrived in Thule, Greenland, in mid-March for the
start of NASA’s 2011 Operation IceBridge, an airborne mission to study changes
in Arctic polar ice. This year’s plans include surveys of Canadian ice caps and
expanded international collaboration.
The state of
Earth’s polar ice sheets, glaciers and sea ice is an important indicator of
climate change and plays a key role in regulating global climate. With
IceBridge, NASA is pushing ahead with its commitment to keep an eye on changes
to polar ice to better understand the effects of climate change.
Since 2009,
Operation IceBridge has flown annual campaigns over the Arctic starting in
March and over Antarctica starting in October.
The mission extends the multi-year record of ice elevation measurements made by
NASA’s Ice Cloud and land Elevation Satellite (ICESat), which stopped
collecting data in 2009, and the upcoming ICESat-2, scheduled for launch in
2016.
“Each
successive IceBridge campaign has broadened in scope,” says IceBridge
project scientist Michael Studinger of Goddard Earth Sciences and Technology Center
at the University of Maryland, Baltimore
County. “This year,
we have more flight hours and flight plans than ever before. We are looking
forward to a busy, fruitful campaign.”
For almost 10
weeks, researchers will operate an array of airborne instruments collecting
data over Arctic land and sea ice.
Among the
highest priority flights is an overnight transit to Fairbanks,
Alaska, to collect sea ice thickness data
across a slice of the Arctic Ocean. Sea ice is
thought to be thinning in recent years in addition to shrinking in the area
covered. Another high-priority flight plan is to fly over the Barnes and Devon ice caps of the Canadian Arctic Archipelago.
“The
Canadian ice caps are notably smaller than the Greenland and Antarctic ice
sheets, but are still significant potential contributors to sea-level change in
the next few decades,” says Charles Webb, deputy cryosphere program
manager at NASA’s Goddard Space Flight Center in Greenbelt, Maryland.
“They also serve as potential early-warning indicators, responding more
sensitively to temperature changes than the more massive ice sheets.”
The IceBridge
campaign also plans to fly for the first time over the European Space Agency’s
ground-based calibration sites for their ice-observing satellite, CryoSat-2.
Flights over calibration sites ultimately are expected to provide data to
evaluate and improve remote-sensing measurements.
Still other
IceBridge missions will retrace paths flown in previous years, such as flights
over Petermann, Jacobshavn, Kangerlussuak and Helheim glaciers. With this
multi-year data, scientists can begin to see how such glaciers – the outlets
through which Greenland loses mass from its
ice sheet – are changing, where ice loss is slowing or accelerating, and why.
The P-3B
aircraft from NASA’s Wallops Flight Facility in Wallops Island,
Virginia, will fly from Thule
and Kagerlussuaq, Greenland, carrying a suite
of instruments. The Airborne Topographic Mapper measures changes in the surface
elevation of the ice by reflecting lasers from the ground back to the aircraft
and converting the readings into elevation maps.
Radar instruments
onboard the P-3B from the University
of Kansas’ Center for Remote Sensing
of Ice Sheets in Lawrence, Kansas,
allow scientists to see snow and ice characteristics at the surface and down to
the bedrock. A gravity instrument from Columbia
University’s Lamont-Doherty Earth
Observatory in Palisades, New York, is used to peer below floating ice
to determine the shape of water-filled cavities below.
Another laser
altimeter, the Land, Vegetation, and Ice Sensor, operates at higher altitudes
to survey large areas. This altimeter will fly solo out of Kangerlussuaq on the
King Air B-200, an aircraft based at NASA’s Langley
Research Center
in Hampton, Virginia.
The IceBridge
campaign is led by Goddard. The Earth Science Project Office at NASA’s Ames Research
Center in Moffett Field, California,
is responsible for integration of science experiments on the aircraft and
mission logistics.
For more
information about Operation IceBridge, visit the NASA website.
