Since a large portion of the Larsen B ice shelf collapsed in 2002, scientists have been studying the region for clues as to why the event occurred. New results suggest a combination of factors: not only has the ice been thinning throughout the present geological era (the Holocene epoch), but human-induced climate change leading to regional Antarctic warming has also played a role in thinning and collapse.
- Domack, Eugene et al. ”Stability of the Larsen B Ice Shelf on the Antarctic Peninsula During the Holocene Epoch.” Nature 436: 681-685. 4 August 2005 at www.nature.com
The ice shelf collapse, some 12,500 square kilometers (km2) in area, was unprecedented during the past 10,000 years. Domack et al. used a variety of paleontological and geological techniques to detect ice shelf thinning. They discovered that while there has been considerable long-term thinning in the ice over the past several thousands of years, it has been the recent warming over the Antarctic peninsula that triggered the collapse. They note that the event is unprecedented in the past 11,500 years – during which entire period the ice shelf has been quite stable.
Implications: With both models and theory predicting that the poles will warm faster than equatorial regions, we may expect increasing instability in the Antarctic ice shelf. Collapse of major ice shelves, such as the Larsen B ice shelf studied by Domack et al., can have adverse impacts to the Antarctic ecosystem, as coastal species are no longer able to survive in the changed environment. The collapse is another signal that climate is changing – and that the theory is more and more being borne out in direct observation.
