News Release

1997-98 Antarctic Research Season Underway

Peer-Reviewed Publication

U.S. National Science Foundation

A new research season is underway in Antarctica, encompassing 175 research projects supported by the National Science Foundation (NSF), the federal agency that funds and manages the U.S. Antarctic Program.

Studies are based out of three research stations -- McMurdo, Amundsen-Scott South Pole and Palmer -- as well as on two research vessels, the Nathaniel B. Palmer and a new vessel, the Lawrence M. Gould.

Research covers earth sciences, glaciology, biology, medicine, oceanography, meteorology, aeronomy and astrophysics. Highlights of the current season include:

Ice Drilling at Siple Dome: Drillers will extract a 1,000-meter core from West Antarctica's Siple Dome, a mound of ice between two fast-flowing ice streams. The ultimate goal is to study the annual layers of ice to improve predictions of climate change. The rivers of ice drain the West Antarctic ice sheet and are critical to its stability. Such current changes in the ice sheet could be on-going responses to the end of the last ice age, pointing to rapid melting, or they may be merely local effects. In any case, West Antarctica's ice, resting on ocean crust in a basin below sea level, may be most vulnerable to melting and raising global sea level.

Siple Dome will also be drilled to understand dynamics of ice flow there, which is mainly in the vertical direction. Scientists will drop instruments into water-filled holes to measure vertical deformation of the ice, in the first such direct measurements of vertical velocity at a deep ice-core site.

Cape Roberts Project Probes Ross Sea Floor: Geologists have extracted a core from the floor of the Ross Sea, drilling from a rig on sea ice off Cape Roberts, about 75 miles north of McMurdo Station. Drilled cores will span the period 30-100 million years ago. Like a history book missing a chapter, Antarctica has no exposed rocks of this age. The Ross Sea rocks can be drilled with relative ease because older beds are tilted up toward the sea floor surface.

During the interval the rocks were deposited, the mega-continent of Gondwanaland underwent its final rupture as New Zealand and Australia pulled northward away from Antarctica. The cores should also shed light on the stability of Antarctica's ice sheets during this time. During the three-year project, a joint venture between the United States, New Zealand, the United Kingdom, Australia, Germany and Italy, the cores will be analyzed at McMurdo Station as they emerge, with a preliminary report available at the field season's end.

Dosvedanya to Drilling at Vostok: In a joint U.S.-Russian-French venture, scientists will complete drilling of the world's deepest ice core this season at Russia's Vostok Station. Drilling last stopped in February, 1997 at a depth of 3,523 meters. Covering over 400,000 years of snowfall, this core spans four glacial-interglacial cycles, furnishing an archive of information on past climate history. The drillers will plumb about 175 more meters of ice, stopping 50 meters above Lake Vostok so as not to contaminate the huge lake sealed beneath the ice sheet.

Ultraviolet Revelations: When more than half of Antarctica's stratospheric ozone disappears each spring, the sun's ultraviolet-B radiation can penetrate to the Earth's surface and into the sea. Scientists will study how UV-B affects the embryos and larvae of three key invertebrates living in shallow waters off the U.S. Palmer Station near the Antarctic Peninsula.

Another project at Palmer will study the photochemistry of seawater surrounding cells in organisms bombarded by increased UV-B. Such chemistry can influence damage to the cell surface. Still other work will quantify how UV light affects plankton, the base of the ocean food chain.

Sea Ice -- From Ship to Space: The growth and shrinkage of the sea ice around Antarctica may be the greatest seasonal event on Earth. Scientists aboard the Nathaniel B. Palmer, NSF's icebreaking research ship, will compare ice and snow on the surface with how they appear in satellite images. Actual measurements of ice on the surface help to validate computer models of climate by making simulations of sea ice more accurate.

Turbulent Mixing: Very cold, saline water, formed in the depths of the southernmost Weddell Sea, feeds dense "bottom water" that spreads throughout the world ocean. U.S. scientists on a British Antarctic Survey research vessel will study the open water at the face of the Filchner-Ronne Ice Shelf, focusing on how the water emerging from beneath the shelf mixes with other water masses.

Tracking Neutrinos and the Big Bang from the South Pole: The Antarctic Muon and Neutrino Detector Array (AMANDA) is a different sort of telescope, buried in the ice cap at the South Pole to look downward into the earth for the telltale traces of neutrinos. Leading the nascent field of neutrino astronomy, AMANDA studies the ghostly subatomic particles emitted from such sources in space as supernovae remnants, pulsars, neutron stars, or active galactic nucleii. The neutrinos pass right through the North Pole, on through the earth, and stream into AMANDA's detectors. Scientists will augment the current array this season by adding three new detector strings to the 14 already in place.

New at South Pole this season will be Viper -- a two-meter diameter telescope designed to look at radiation left over from the Big Bang, on a smaller scale than has been done from the Pole before (initially, with an angular scale of one-half degree at a six-millimeter wavelength; in the future, on a finer scale).

Astronomy by Balloon: Antarctica's summer weather provides a stable ride for instruments hung beneath a balloon, which floats around Antarctica at a steady height above most of the atmosphere, providing a cheaper way to get scientific experiments into space. This year, a spectrometer will sail for 10 days around the continent, tracking gamma rays emitted by neutron stars, black holes, the center of the galaxy, and other features.

"Icebreaker" to Herald New South Pole Station: In early December, NSF will formally break ground -- or break the ice -- to begin constructing a new station at the South Pole. During the first phase of construction, a new garage and shop, fuel storage system, and power plant will be built. This season, the site will be prepared and a new arch to house the garage and shop will be erected. Also, a new Atmospheric Research Observatory will be dedicated in January at the South Pole, replacing the overcrowded and aging Clean Air Facility. The ARO will offer twice the space of its predecessor for research on climate, ozone, ultraviolet light, and other atmospheric studies.

Editors: For summaries of all field projects of the U.S. Antarctic Program during the 1997-98 season, request publication NSF 97-167 from pubs@nsf.gov or call 301-947-2722.


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