Collapse of Antarctic Ice Shelf Unprecedented
The Antarctic Peninsula is undergoing greater warming than almost anywhere on Earth, a condition perhaps associated with human-induced greenhouse effects. According to the cover article published in the August 4 issue of the journal Nature, the spectacular collapse of Antarctica's Larsen B Ice Shelf, an area roughly the size of Rhode Island, is unprecedented during the past 10,000 years. Eugene Domack, professor of geosciences at Hamilton College and the author of the paper, has been the lead scientist of a multi-institutional, international effort that combines a variety of disciplines in examining the response of the Antarctic Peninsula to modern warming. Domack says, "Our work contributes to the understanding of these changes -- where they are occurring first and with greatest magnitude and impact upon the environment."
Domack's paper provides evidence that the break-up of the ice shelf was caused by a combination of long-term thinning (by a few tens of meters) over thousands of years and short term (multi-decadal) cumulative increases in surface air temperature that have exceeded the natural variation of regional climate during the Holocene period (the last 10,000 years since the end of the last Ice Age).
Using data collected from six sediment cores in the vicinity of the former ice shelf, Domack and his colleagues conclude that the Larsen ice shelf had been intact but was slowly thinning during the course of the current interglacial period. They attribute the recent collapse to the effects of climate warming in the Antarctic Peninsula, which is more pronounced in this region than elsewhere in Antarctica or the rest of the world. The Larsen B ice shelf is not alone in its demise. In recent years, the Antarctic Peninsula has lost ice shelves totaling over 4825 square miles.
Domack, who has taken more than 100 undergraduates to Antarctica since 1987, studies the paleohistory of the Larsen Ice Shelf. He was awarded $851,941 from the National Science Foundation Office of Polar Programs in 2004. Domack was a 2004 Guggenheim Fellow, a Joint Oceanographic Institutions 2000 Distinguished Lecturer and an invited speaker at over 20 international conferences including the 1999 American Association for the Advancement of Science annual meeting.
Collaborators on the project include researchers from Hamilton College; Colgate University, University of New Hampshire, Southern Illinois University - Carbondale, University of Barcelona and Queen's University in Kingston, Ontario.