Press Release


NSF PR 02-22 - April 3, 2002

Hamilton College

Scientists to Discuss Climate Change on Antarctic Peninsula
Recent Collapse of Larsen B ice shelf one likely focus of discussions


View looking southwest from Cape Marsh toward the Larsen-B embayment showing icebergs remaining from the 1999 collapse of the Larsen B Ice Shelf and sediment-laden melt water plumes generated during the recent austral summer.
Photo credit: NSF photo / David Tewksbury, Hamilton College
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A photograph of the sea floor collected January 2002 in front of the Larsen B ice shelf. The position from which the photo was taken was recently beneath a much larger Larsen B shelf as recently as two years ago. The bottom shows a seafloor paved with cobbles and pebbles that were probably released from icebergs as the ice shelf broke up for the first time in 1999. Water depth is about 500 meters (1640 feet).
Photo credit: NSF photo / Eugene Domack, Hamilton College
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Scientists from around the globe will meet in New York State later this week to discuss environmental changes on the Antarctic Peninsula, the effects of a long-documented warming trend there on plants, animals and ice conditions, and whether similar conditions have existed previously over recent geological time.

  The peninsula, which extends northward toward South America, was the site of the collapse of an enormous ice shelf, dubbed the Larsen B, in late March that made headlines around the world.

The conference, supported by the National Science Foundation (NSF), is entitled "Antarctic Peninsula Climate Variability: A Historical and Paleoenvironmental Perspective."  It is jointly sponsored by the Hamilton College Environmental Studies Program and Colgate University and will be held April 3-5 at the Hamilton campus in Clinton, N.Y.

Scott Borg of NSF's Office of Polar Programs, who will make opening remarks at the conference, said the meeting had been planned before the recent disintegration of the Larsen B ice shelf because the Antarctic Peninsula has long been the focus of multidisciplinary scientific investigations into long-term climate trends.  Other ice shelves have disintegrated along the peninsula in recent years and other severe and rapid changes in the ecosystem there have attracted the interest of scientists.

The conference goals are to begin to understand how atmospheric and oceanographic factors have affected the climate system of the Peninsula in the past, using evidence from marine sediment and ice cores.  Conference organizers also will look at current conditions and attempt to discern links between the local conditions on the Peninsula and other regional and global climate events.

Even in Antarctica, there appear to be marked variations in climate and temperature trends.  Researchers with NSF's Long-Term Ecological Research project in Antarctica's Dry Valleys recently published a paper in Nature arguing that the continent of Antarctica has cooled measurably over the last 35 years. That paper acknowledges the existence of a documented warming trend on the Peninsula.

Among the topics on the agenda are the decay of ice shelves on the Peninsula, the decrease in sea ice cover in the Southern Ocean around the Peninsula; increases in mean annual summer and winter temperatures; shifts in penguin populations; and changes in vascular plant density and distribution.

The conference also gives scientists their first opportunity to review sea-floor data from the Larsen B shelf area that were collected on an NSF-supported research cruise earlier this year. Eugene Domack, a conference organizer and a professor of geology at Hamilton College, conducted a ship-borne survey of the region aboard the NSF's research vessel Nathaniel B. Palmer a few months prior to the Larsen B shelf collapse.

Domack said that sea-floor photographs illustrate a seascape littered with a pavement of stones most likely released by icebergs from the previous break up of segments of the Larsen B system in 2000 and 1999.  Preliminary study of sediment cores from in front of the Larsen B, he added, suggest that the Larsen B collapse may be unprecedented in the roughly 12,000 years since the last ice age.

Borg noted that the Larsen B disintegration will provide scientists with an opportunity to study areas of the ocean floor that previously were inaccessible because they were covered by the ice shelf and begin to gather evidence that will clarify the history of the Larsen B.

For more information about the workshop from the Hamilton College Web site, see http://academics.hamilton.edu/antarctica

To read a press release about the climate study published in Nature, see http://www.nsf.gov/od/lpa/news/02/pr0203.htm

For more information about the U.S. Antarctic Program, see http://www.nsf.gov/od/lpa/news/media/99/fs_usap.htm

For additional images, text, and a map of the cruise to the Antarctic Peninsula from the Hamilton College Web site, see http://www.hamilton.edu/news/exp/Antarctica2001/

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