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'Our emissions will go up like a rocket,' Canada's leading scientists warn
A new study says the Arctic could be ice-free in summer within two decades, writes Margaret Munro in Vancouver.
Margaret Munro, The Ottawa Citizen
Published: Wednesday, May 02, 2007The federal government's plan to cut greenhouse gases falls far short of what is needed, say leading climate scientists, who predict Canada's emissions are going to continue to climb "like a rocket."
"It's not nearly sufficient to do what we need to do in order to make a difference on this issue, or to make an appropriate Canadian contribution to solving this problem," says Richard Peltier, a senior atmospheric physicist at the University of Toronto and co-author of a recent United Nations report spelling out how humanity's carbon emissions are altering the global climate system.
The full impact of increased carbon dioxide and other greenhouse gases in the atmosphere is causing polar ice to disappear at a rate almost three times faster than projected by climate models, according to new findings published this week in Geophysical Research Letters.
The Arctic could be ice-free in summer within two decades, says the study. The shrinking summertime ice is about 30 years ahead of model projections used by the United Nation's Intergovernmental Panel on Climate Change (IPCC) that recently suggested the Arctic would not lose its ice before 2050. Mr. Peltier said the Harper government has made a "terrible mistake for the country" by opting to go with intensity targets instead of a carbon tax.
"Our emissions will go up like a rocket because (the plan) is based on intensity-based targets," Mr. Peltier said in an interview after a news briefing in Vancouver yesterday. "We need actual emissions reductions that gradually tighten the screws on emissions, and we need to put a value on a tonne of carbon."
Intensity-based targets require companies to reduce the emissions per unit of production, but could see total emissions climb along with production.
Mr. Peltier and his colleagues called the media conference to highlight research probing the dramatic changes underway in the polar regions as temperatures climb. But several of the scientists used the occasion to express deep disappointment over the government plan unveiled last week by Environment Minister John Baird.
Deep cuts, in the order of 60 to 90 per cent of global carbon emissions by 2050, are needed to avoid triggering climate meltdown, say the scientists, adding the government's plan to try to slow the rise in Canadian emissions over the next few years and cut emissions by about 20 per cent by 2020 does not go nearly far enough.
They also say Canada, as a polar nation, will be one of the countries most impacted by climate change and needs a comprehensive emissions-reduction strategy at home so it can call for global reductions.
"The only way we can have influence in the (international) process is first of all by showing some national leadership so we can go to China with a straight face and say, 'We shouldered some of this -- can you guys now help out?'" said Gordon McBean, chair of the Canadian Foundation for Climate and Atmospheric Sciences.
"We also need a strategy that supports technology that we can use locally and use internationally, and we need to have a science program that makes it clear where the dangerous tipping points are," he said
Many researchers say that if average global temperatures climb much more than 2.0 or 2.5 C, the climate system will hit dangerous tipping points that could see the Greenland ice sheet melt, leading to a rise in sea levels of as much as seven metres.
When the summer ice goes, scientists say it will be an extraordinary change for the planet, which has had a polar ice cap for close to a million years.
The new study compares advanced climate models with observations made by satellites, aircraft and ships. On average, the computer models simulate a loss in September ice cover of 2.5 percent per decade from 1953 to 2006, compared to observations showing September ice actually declined at a rate of about 7.8 per cent a decade during the 1953-2006 period. The ice is at its yearly minimum in September.
"This suggests that current model projections may in fact provide a conservative estimate of future Arctic change, and that the summer Arctic sea ice may disappear considerably earlier than IPCC projections," lead author Julienne Stroeve of the U.S. National Snow and Ice Data Center said in a statement released with the study. The IPCC, which relied heavily on climate models, predicted in February the Arctic could see ice-free summers anytime from 2050 to beyond 2100.
