Tuesday, September 2, 2008
Scientists Report Massive Ice Shelf Loss During Summer of 2008
As you may know our Pax Arctica team was the first on the ice to witness the dramatic events which have occurred on the Ellesmere ice shelves this Summer. They were even more dramatic developments after we returned. The losses have been terrible this season as described in the report below and on the maps and photos at the following links: http://www.people.trentu.ca/~dmueller/iceshelfloss2008/
The photo on the right, taken by us on July 21, 008 shows the eastern portion of the Ward Hunt Ice Shelf with Cape Albert Edward in the background before widely reported calving of roughly 20 km2 of the ice shelf. The photo on the left shows the same view in mid-August, 2008.
Canada’s Ice Shelves Lose 23 % of their Area, Number Reduced from Five to Four Tuesday, September 2, 2008, Peterborough, Ontario
Following the widely reported July calving from the Ward Hunt Ice Shelf in the Canadian Arctic, massive changes have occurred to ice shelves located along the northern coast of Ellesmere Island. The entire 50 km2 Markham Ice Shelf broke away in early August and is now adrift in the Arctic Ocean. Two large sections of ice detached from the Serson Ice Shelf, shrinking this ice feature by 122 km2 (60 %). The Ward Hunt Ice Shelf also continued to break-up, losing an additional 22 km2.
“These substantial calving events underscore the rapidity of changes taking place in the Arctic,” said expert Dr. Derek Mueller, who has been studying the far north of Canada as the Roberta Bondar Fellow in Northern and Polar Studies at Trent University. “These changes are irreversible under the present climate and indicate that the environmental conditions that have kept these ice shelves in balance for thousands of years are no longer present.”
This summer’s ice shelf loss totals 214 km2, which is over three times the area of Manhattan Island. The detached pieces of ice shelves have broken into numerous ‘ice islands’ (tabular icebergs) whose fate could take many forms. “They could circulate in the Beaufort Gyre and float along the northern edge of the Queen Elizabeth Islands toward the Beaufort Sea or they could enter the Canadian Archipelago,” explained Dr. Martin Jeffries of the US National Science Foundation and University of Alaska Fairbanks, and who has studied the Ellesmere ice shelves since 1982. The Canadian Ice Service, Environment Canada, is tracking the broken pieces.
“Reduced sea ice conditions and unusually high air temperatures have facilitated the ice shelf losses this summer” explained Dr. Luke Copland, Director of the Laboratory for Cryospheric Research at the University of Ottawa. “And extensive new cracks across remaining parts of the largest remaining ice shelf, the Ward Hunt, mean that it will continue to disintegrate in the coming years”. This means that Quttinirpaaq National Park, Canada’s most northerly, may soon lose its last remaining ice shelf after the loss of its other ice shelf, the Markham, this summer.
Only recently named for a respected Arctic scientist, Harold Serson, the Serson Ice Shelf dammed a 76 km2 freshwater lake measuring approximately four meters deep that sits atop the sea water. The loss of this rare ecosystem is a possibility since it is dependent on the ice shelf staying intact. Dr. Warwick Vincent, Director of Laval University's Centre for Northern Studies and a researcher in the program ArcticNet, has been studying the ecology of northern Ellesmere Island for more than ten years. He has just returned from his latest expedition to the area, where he observed dramatic changes along the coast. “These ice shelves are formed from the Arctic's thickest and oldest marine ice” he says, “and the extent of their loss this season is significant. Unique ecosystems that depend on this ice are on the brink of extinction.”
The Ellesmere ice shelves are composed of ancient sea ice and accumulated snow along with glacier ice in some cases. Up to 4,500 years old and approximately 40 m thick, these features are vastly different from ordinary sea ice. More than 90 per cent of Canada’s ice shelves have been lost over the past century, with most of these losses occurring during a warm period in the 1930s and 1940s. Temperatures in the Arctic are now even higher than they were then and a period of renewed ice shelf break-up has ensued since 2002.
This research was undertaken in collaboration with the Canadian Ice Service with logistical support from Polar Shelf (Natural Resources Canada) and the Canadian Rangers (National Defence). Luc Hardy of Pax Arctica, an initiative in collaboration with Green Cross International, provided photos and satellite imagery. Financial assistance was provided by ArcticNet, Canadian Foundation for Innovation and the Natural Sciences and Engineering Research Council (NSERC) of Canada.
For further information including satellite images and photos, please visit: www.trentu.ca/iceshelf, www.ice.ec.gc.ca
Dr. Derek Mueller
Tel: (705) 748-1011, ext. 7153
Dr. Luke Copland
Department of Geography
University of Ottawa
Tel: (613) 562-5800, ext. 2826
Canadian Ice Service, Ottawa, ON
c/o Environment Canada Media Inquiries
Tel: (819) 934-8008
Dr. Warwick Vincent
Centre d’études nordiques
Tel: (418) 656-3340
Dr. Martin Jeffries
National Science Foundation
Office of Polar Programs
Tel: (703) 292-7442