Flights are underway from Fairbanks, Alaska, with
NASA’s C-130 Hercules aircraft to study the connection between retreating Arctic
sea ice and climate change.
Image Credit:
NASA/Patrick Lynch
Over the past few decades, average global temperatures have been on the rise,
and this warming is happening two to three times faster in the Arctic. As the
region’s summer comes to a close, NASA is hard at work studying how rising
temperatures are affecting the Arctic.
NASA researchers this summer and fall are carrying out three Alaska-based
airborne research campaigns aimed at measuring greenhouse gas concentrations
near Earth’s surface, monitoring Alaskan glaciers, and collecting data on Arctic
sea ice and clouds. Observations from these NASA campaigns will give researchers
a better understanding of how the Arctic is responding to rising
temperatures.
The Arctic Radiation – IceBridge Sea and Ice Experiment, or ARISE, is a new
NASA airborne campaign to collect data on thinning sea ice and measure cloud and
atmospheric properties in the Arctic. The campaign was designed to address
questions about the relationship between retreating sea ice and the Arctic
climate.
Arctic sea ice reflects sunlight away from Earth, moderating warming in the
region. Loss of sea ice means more heat from the sun is absorbed by the ocean
surface, adding to Arctic warming. In addition, the larger amount of open water
leads to more moisture in the air, which affects the formation of clouds that
have their own effect on warming, either enhancing or reducing it.
Changes in more than 130 Alaskan glaciers are being
surveyed by scientists at the University of Alaska-Fairbanks in a DHC-3 Otter as
part of NASA’s multi-year Operation IceBridge.
Image Credit:
Chris Larsen, University of
Alaska-Fairbanks
“ARISE will link clouds and sea ice in a way that improves our computer
models of the Arctic,” said Tom Wagner, cryospheric sciences program manager at
NASA Headquarters in Washington. “Our goal is to better understand both the
causes of Arctic ice loss and the connections to the overall Earth system.”
The ARISE campaign, using NASA’s C-130 Hercules aircraft from Wallops Flight
Facility in Virginia, had its first science flight on Sept. 4 and has already
carried out several surveys of sea ice and cloud conditions. The campaign is
based in Fairbanks, Alaska.
“We are off to a great start collecting a timely and unique dataset to help
better understand the potential influence of clouds on the Arctic climate as sea
ice conditions change,” said William Smith, ARISE principal investigator at
NASA’s Langley Research Center in Hampton, Virginia.
CARVE, or Carbon in Arctic Reservoirs Vulnerability Experiment, is a
five-year airborne research campaign that uses instruments aboard NASA aircraft
to measure air and surface conditions and concentrations of gases like carbon
dioxide, carbon monoxide and methane. Using NASA’s C-23 Sherpa aircraft, CARVE
flies approximately two weeks per month from May to November. Now that the
mission is in its fourth year, researchers are building a detailed picture of
how the land and atmosphere interact in the Arctic.
In high-latitude areas like Alaska, frozen ground known as permafrost can
trap large amounts of carbon dioxide and methane produced by layers of decayed
plant and animal matter. As permafrost temperatures have been increasing faster
than air temperatures in the Arctic, scientists have questioned whether these
heat-trapping gases could be released into the atmosphere, increasing their
global concentrations.
“The exchange of carbon between the land and the atmosphere is very important
– but uncertain,” said Charles Miller, a scientist at NASA’s Jet Propulsion
Laboratory in Pasadena, California, and principal investigator of CARVE.
Another area of interest in Alaska is its glaciers. Researchers at the
University of Alaska Fairbanks have been taking airborne measurements of glacier
surface height using a laser altimeter, an instrument that bounces a laser off
of the ice surface and measures how long it takes to return. These flights are
part of NASA’s Operation IceBridge, an airborne campaign that studies changes to
land and sea ice in the Arctic and Antarctic.
University researchers observe Alaskan glaciers twice a year, before and
after the melt season, to determine how much ice they have lost or gained. The
scientists have surveyed between 130 and 140 glaciers going back to the
mid-1990s. IceBridge’s Alaska flights have found that glaciers across the state
are declining rapidly, with those terminating on land and in lakes losing mass
faster than expected.
Researchers are also finding that there is considerable variation in mass
loss throughout Alaska. “One glacier might be doing better than the one next to
it,” said Evan Burgess, University of Alaska Fairbanks scientist and member of
the IceBridge Alaska team.
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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