Steve Cole
Headquarters, Washington
202-385-0918
stephen.e.cole@nasa.gov
RELEASE: 11-195
NASA SETS SAIL ON SECOND LEG OF ARCTIC OCEAN RESEARCH VOYAGE
WASHINGTON -- Scientists embark this week from Alaska on the second
and final campaign of a NASA field campaign to study how changing
conditions in the Arctic affect the ocean's chemistry and ecosystems.
On June 25, the ICESCAPE mission, or "Impacts of Climate on Ecosystems
and Chemistry of the Arctic Pacific Environment," resumes its
shipborne investigation of the impacts of climate change in the
Chukchi and Beaufort seas along Alaska's western and northern coasts.
Research teams depart from Dutch Harbor, Alaska, aboard the U.S.
Coast Guard Cutter Healy.
The field campaign takes 47 scientists for five weeks to the Arctic
Ocean, where a variety of instruments will be used onboard the Healy
and deployed into the ocean and on the sea ice. Following the
mission's first campaign in summer 2010, the second year of sampling
seeks to find year-to-year differences and provide data for new lines
of investigation.
Combined observations from the field and from NASA satellites are
critical to understanding the Arctic, where the signals of climate
change are amplified. The accelerated decline of Arctic sea ice
extent and thickness exemplifies this trend, and scientists want to
know how this change affects other ocean processes and marine life.
"Multidisciplinary field campaigns like ICESCAPE take advantage of
simultaneous satellite and field measurements," said Carlos Del
Castillo, acting program manager of the Ocean Biology and
Biogeochemistry Program at NASA Headquarters in Washington. "The
advantage of satellites is that we can routinely collect observations
of the whole planet. That data combined with field work and computer
modeling gives us a better understanding of how the Earth system
works."
Phytoplankton, microscopic organisms that live in watery environments,
are a key focus of the campaign. They form the base of the aquatic
food web, participate in cycling Earth's carbon between the
atmosphere and the ocean and are susceptible to climate change. NASA
has monitored changes in phytoplankton from space worldwide with the
Moderate Resolution Imaging Spectroradiometer instrument on the Aqua
satellite and the Sea-viewing Wide Field-of-view Sensor, which ended
observations in 2010.
"Last year, ICESCAPE nailed down quite a few things in terms of the
phytoplankton work," said Kevin Arrigo of Stanford University in Palo
Alto, Calif., the mission's chief scientist. "We know pretty well now
how fast they are growing and what they are responding to. The repeat
measurements from this voyage will help us confirm what's going on."
The 2010 campaign gave researchers a glimpse of what might be
happening in Barrow Canyon, one of most productive areas for
phytoplankton growth in the Beaufort-Chukchi region. While many
blooms last just a few weeks before consuming all of the local
nutrients and declining, the bloom in Barrow Canyon gets its start in
spring and carries on through summer.
Scientists think the extended bloom can be explained by unique
patterns in the path and timing of ocean currents. In spring, a
stream of water carries nutrients from the Pacific Ocean up through
the Bering Strait and delivers them to Barrow Canyon. The water hugs
the coast and arrives quickly, providing the nutrients for the bloom
to get its start. Two other streams take a more circuitous route and
arrive later, sustaining the bloom through summer.
"With this year's voyage, we hope to acquire more details about the
physical processes pulling nutrients from deep water to the surface,"
Arrigo said.
New to ICESCAPE in 2011, the ship will forge north through the
Beaufort Sea to explore the relationship between shallow water on the
continental shelf and deep water in the Canada Basin. Phytoplankton
on the shallow shelves tend to flourish when the ice retreats and
scientists want to find out what feeds the bloom.
Last year, researchers saw some indication that nutrients were moving
between deep and shallow water. Wind unexpectedly blew thick,
multiyear sea ice south to the edge of the shelf, at some places up
to 20 feet thick. The ice proved too thick for the icebreaker to
penetrate. The Healy, the newest and most technologically advanced
U.S. polar icebreaker, is designed to break four-and-a-half feet of
ice continuously at three knots.
This year, the field campaign begins two weeks later, which means the
Healy is expected to encounter thinner, summer ice and thus have a
better chance of exploring the ecosystems in water that spends most
of the year under a blanket of ice.
For updates on the five-week ICESCAPE voyage, visit the mission blog
at:
For more information about NASA and agency programs, visit:
-end-
To subscribe to the list, send a message to:
hqnews-subscribe@mediaservices.nasa.gov
To remove your address from the list, send a message to:
hqnews-unsubscribe@mediaservices.nasa.gov
No comments:
Post a Comment