New Antarctic ice core to provide clearest climate record yet

Editor’s note: Ice Coring and Drilling Services of the University of Wisconsin–Madison built and is operating a state-of-the-art, deep ice-coring drill that is the engine behind an unprecedented Antarctic research project to record greenhouse gas levels over the last 100,000 years. The project completed its first year at the West Antarctic Ice Sheet Divide. 

DURHAM, N.H. — After enduring months on the coldest, driest and
windiest continent on Earth, researchers closed out the inaugural
season on an unprecedented, multiyear effort to retrieve the most
detailed record of greenhouse gases in Earth’s atmosphere over the last
100,000 years.

Working as part of the National Science Foundation’s West Antarctic Ice Sheet Divide (WAIS Divide) Ice Core Project, a team of scientists,
engineers, technicians and students from multiple U.S. institutions
have recovered a 580-meter (1,900-foot) ice core — the first section of
what is hoped to be a 3,465-meter (11,360-foot) column of ice detailing
100,000 years of Earth’s climate history, including a precise
year-by-year record of the last 40,000 years.

The dust,
chemicals and air trapped in the two-mile-long ice core will provide
critical information for scientists working to predict the extent to
which human activity will alter Earth’s climate, according to the chief
scientist for the project, Kendrick Taylor of the Desert Research
Institute of the Nevada System of Higher Education. DRI, along with the
University of New Hampshire, operates the Science Coordination Office
for the WAIS Divide Project.

WAIS Divide, named for the high-elevation region that is the
boundary separating opposing flow directions on the ice sheet, is the
best spot on the planet to recover ancient ice containing trapped air
bubbles — samples of the Earth’s atmosphere from the present to as far
back as 100,000 years ago.

While other ice cores have been used to develop longer records of
Earth’s atmosphere, the record from WAIS Divide will allow a more
detailed study of the interaction of previous increases in greenhouse
gases and climate change. This information will improve computer models
that are used to predict how the current unprecedented high levels of
greenhouse gases in the atmosphere caused by human activity will
influence future climate.

The WAIS Divide core is also the Southern Hemisphere equivalent of a
series of ice cores drilled in Greenland beginning in 1989, and it will
provide the best opportunity for scientists to determine if
global-scale climate changes that occurred before human activity
started to influence climate were initiated in the Arctic, the tropics
or Antarctica.

The new core will also allow investigations of biological material
in deep ice, which will yield information about biogeochemical
processes that control and are controlled by climate, as well as lead
to fundamental insights about life on Earth.

Says Taylor, "We are very excited to work with ancient ice that fell
as snow as long as 100,000 years ago. We read the ice like other people
might read a stack of old weather reports."

The WAIS project took more than 15 years of planning and
preparation, including extensive airborne reconnaissance and
ground-based geophysical research, to pinpoint the one-square-kilometer
(less than a square mile) space on the 932,000-square-kilometer
(360,000-square-mile) ice sheet that scientists believe will provide
the clearest climate record for the last 100,000 years.

With only some 40 days a year when the weather is warm enough for
drilling — yesterday’s temperature was a balmy -15 degrees Celsius (5
degrees Fahrenheit) — it is expected to take until January 2010 to
complete the fieldwork.

For the project, Ice Coring and Drilling Services at UW–Madison built and is operating a state-of-the-art, deep
ice-coring drill, which is more like a piece of scientific equipment
than a conventional rock drill used in petroleum exploration. The U.S.
Geological Survey National Ice Core Laboratory in Denver designed the
core handling system. Raytheon Polar Services Corporation provides the
logistical support. The NSF Office of Polar Programs-U.S. Antarctic
Program funds the project. The core will be archived at the National
Ice Core Laboratory, which is run by the USGS with funding from NSF.