New Antarctic Ice Core To Provide Clearest Climate Record Yet
By David Sims, Institute for the Study of Earth, Oceans, and Space
January 23, 2008
After enduring months on the coldest, driest, and windiest continent on
Earth, researchers today closed out the inaugural season on an unprecedented,
multi-year 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 UNH, 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
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 of the University of Wisconsin-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.
For more information on WAIS Divide, including the project media guide,
go to http://www.waisdivide.unh.edu.