Ice floes float in Baffin Bay above the Arctic circle as seen from the Canadian Coast Guard icebreaker Louis S. St-Laurent on July 10, 2008. Photograph by: Jonathan Hayward/The Canadian Press/Files , Postmedia News
OTTAWA — Glacier monitoring conducted by the federal government in Canada’s High Arctic shows the shrinking of ice caps that started in the late 1980s “has accelerated rapidly since 2005” and is part of a “strongly negative trend,” according to internal government documents.
The federal government data raise a number of questions about climate change in Canada’s North and what the melting ice caps mean for the country’s economy and environment in the future.
A memo requested by the deputy minister of Natural Resources Canada (NRCan) — and obtained by Postmedia News under access-to-information legislation — highlights what the federal government acknowledges are rapidly melting ice caps in Canada’s Arctic over the last nine years.
The data were obtained through NRCan’s Climate Change Geoscience Program, which monitors annual glacier mass fluctuations and sea level changes at sites across the Canadian High Arctic.
The federal government maintains glacier monitoring sites in the Canadian High Arctic for four ice caps: Devon, Meighen, Melville and Agassiz.
“Glacier monitoring conducted by the Earth Sciences Sector (ESS) in Canada’s High Arctic indicates that shrinking of ice caps started in the late 1980s, and has accelerated rapidly since 2005,” says an October 2013 memo to NRCan’s deputy minister, who reports to federal Natural Resources Minister Joe Oliver.
Preliminary data and observations — including on Arctic sea-ice coverage, upper atmospheric temperatures and field camp observations — indicate 2013 was cooler than the recent trend.
While the ice melt in 2013 doesn’t appear as bad as recent years, “it does not significantly alter the strongly negative trend observed since 2005 for this region,” say the briefing materials.
David Burgess, research scientist and glaciologist with Natural Resources Canada, explained that since 2005 there has been a persistent high-pressure system over Greenland, which has acted to draw in more warm air from southerly latitudes and contributed to a warming High Arctic.
This same kind of system didn’t develop in 2013, which may explain the cooler temperatures last summer, he said.
Federal data show the Devon ice cap’s northwest sector has lost 1.6% of its mass since the 1960s, the Meighen approximately 11% of its mass and the Melville about 13%, he said. However, approximately 30 to 40% of the ice mass lost has happened since 2005.
“Since 2005 it has enhanced quite significantly,” Burgess said in an interview.
The main consequence of shrinking Arctic ice caps is increasing sea levels, he said, which can impact Canadian coastlines depending on their resiliency to erosion and inundation.
Green Party Leader Elizabeth May, a former senior policy adviser to the federal environment minister in the Mulroney government, said the federal information on melting ice caps is “very troubling” but also not surprising because other international data have reached similar conclusions.
All Canadians should be concerned about climate change in the Arctic, she said. Along with directly impacting Inuit hunting, melting Arctic ice also will contribute to more extreme weather events in Canada such as droughts and flooding, she said.
Posts
No comments:
Post a Comment