Getting a better fix on sea level rise 'is a big deal'

Getting a better fix on sea level rise 'is a big deal'

Jay Gulledge, senior scientist at the Pew Center for Global Climate Change and a fellow with the Center for a New American Security, pointed to estimates of sea level rise.

The last report of the Intergovernmental Panel on Climate Change, issued in 2007, predicted the sea would rise between 7 and 23 inches by 2100 -- but issued a giant caveat. The IPCC cautioned that an additional rise could come from rapid and unpredictable melting of massive ice sheets in Greenland and Antarctica, which it didn't attempt to estimate.

Since then, scientists have raced to improve their understanding of the processes that contribute to sea level rise. Many studies now suggest that seas will rise 1 to 2 meters by 2100.

But as Gulledge noted, there's a big difference between 1 meter of sea level rise -- roughly 3 feet -- and 2 meters. "We're at a point now where we can't say we're not going to get 2 meters of sea level rise by 2100, though it's perhaps not likely," he said.

That's a problem for national security planners, who normally look at a wide range of future scenarios -- including many that are unlikely, though potentially devastating.

But climate scientists said that making those kinds of determinations is difficult and in many cases is hampered by the amount of computing power available to run climate models.

"We've just barely gotten to the stage where we can make these projections," said Bruce Cornuelle, a physical oceanographer at Scripps. "The problem of putting probabilities on them is much harder."

For example, the Met Office, the United Kingdom's weather service, recently updated its climate change projections for Britain, indicating the probability of different scenarios.

Defense experts negotiate with modelers for probabilities

"We had to use a low-resolution [climate] model," she said. "We were constrained by the computer model we had. And what that doesn't do is give you the outliers" -- extreme, but low probability, events.

Still, climate scientists said their models have improved greatly since the last report by the Intergovernmental Panel on Climate Change was released in 2007. At the Hadley Center, they're running a new model -- for the next IPCC report -- that covers changes in the atmosphere, the ocean, the carbon cycle, chemistry and land use.

Observations of key aspects of climate change are also improving. Scripps glaciologist Helen Fricker noted that scientists now understand how melting ice sheets in Greenland and Antarctica and glaciers on land contribute to sea level rise -- something that was an open question just a few years ago.

That, she said, factors into understanding what the future may bring.

Meanwhile, the Defense Department is beginning to negotiate directly with climate modelers to get the future forecasts it needs.

According to Titley, the Navy and Air Force are in talks with the National Oceanic and Atmospheric Administration to develop next-generation climate models that will incorporate knowledge of the social sciences, agriculture, and marine ecosystems -- "not just understanding that temperature is going up 'X' degrees."

Supporters of the proposed effort include NOAA Administrator Jane Lubchenco and White House science adviser John Holdren, Titley said.

"We are putting this together," he said. "This is going to be a big deal for us."

Canada pledges to phase out most coal-fired power plants

ClimateWire, 24 June 2010, By Christa Marshall

The Canadian minister of the environment, Jim Prentice, also said the country would invest $400 million this fiscal year to help developing countries control greenhouse gases and adapt to climate change as part of an international climate pledge forged in Copenhagen, Denmark, last year. There, industrialized countries promised $30 billion collectively for such assistance over a three-year period.

"Today's announcement positions Canada one step closer to reaching its goal of being a clean energy superpower, " Prentice said yesterday in a speech in Ottawa.

The dual moves came as the Canadian government has been under pressure to make climate change a focus of the G-20 and G-8 summits, which Canada is hosting later this week.

It is unclear how far the proposed coal-plant regulations, which are planned for formal release in 2011, and the international financing announcement would act in practice, several analysts said yesterday.

"There are still details that need to be explained or strengthened to make this really meaningful," said Matthew Bramley of the Pembina Institute, a Canadian environmental think tank.

Among those uncertainties are how many coal plants would be built before the rules kick in in 2015, he said. Even if most of the country's existing coal plants were phased out, the government would need to find significant emission cuts in other sectors to meet Canada's pledged goal to cut greenhouse gas output 17 percent below 2005 levels by 2020, according to Bramley.

Other environmentalists claimed the coal plant rules won't do anything additional to cut greenhouse gases, since the requirements could be met mainly with coal-plant restrictions already moving forward in the province of Ontario.

Generating funds that are 'additional'

The $400 million would supply 4 percent of international funds this year pledged by industrialized countries to developing nations as a result of the Copenhagen climate negotiations, Prentice said. Additional money from Canada would be forthcoming as part of the $30 billion pledge by industrialized nations to provide financial support to nations vulnerable to deforestation and climate change impacts, he said.

He said the funds would be "additional," but did not specify whether the money would be new cash or shifted from existing international development programs in the Canadian budget. International activists have been pressing for firm commitments from countries that money offered for the $30 billion initiative will not take away from existing aid efforts (ClimateWire, June 16).

Under the new coal requirements, all new coal-fired units would have to meet a new "performance standard" requiring them to be "on parity" with the emissions of natural gas plants, Prentice said. Natural gas produces roughly half as much greenhouse gases as coal.

The rules would apply to both new generators and old plants about to be retired. More than half, or 33, of Canada's 51 coal units are scheduled to reach the end of their economic lives in the next 15 years.

"Our regulation will be very clear -- when each coal burning unit reaches the end of its economic life, it will have to meet the standard or close down," Prentice said.

Coal provides almost 20 percent of Canada's electricity and accounts for 13 percent of Canada's overall emissions, according to government statistics. That is a much lower percentage than in the United States, where coal fires more than 45 percent of electricity.

The Canadian coal proposals would reduce emissions by about 15 megatonnes, or the equivalent of 3.2 million vehicles, according to the Canadian government.

Sierra Club Canada slammed the coal plant proposals as a "joke," since the rules would start in 2015 and would allow the construction of new plants. More than 60 percent of the coal reduction would come from Ontario's pledged commitment to close all its coal plants by 2014, meaning the country is not further along than where it was before the announcement, said Gillian McEachern of Environmental Defence.

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