Warming of two degrees inevitable over Canada: study

Warming of two degrees inevitable over Canada
SFU geographer Kirsten Zickfeld notes in a new paper she has co-authored that northern hemisphere dwellers will suffer more severe effects of climate change than others.
(PhysOrg.com) -- Even if zero emissions of greenhouse gases were to be achieved, the world’s temperature would continue to rise by about a quarter of a degree over a decade. That’s a best-case scenario, according to a paper co-written by a Simon Fraser University researcher.

New climate change research - Climate response to zeroed emissions of and aerosols — published in Nature's online journal, urges the public, governments and industries to wake up to a harsh new reality.

“Let’s be honest, it’s totally unrealistic to believe that we can stop all emissions now,” says Kirsten Zickfeld, an assistant professor of geography at SFU. “Even with aggressive greenhouse gas mitigation, it will be a challenge to keep the projected global rise in temperature under 2 degrees Celsius,” emphasizes Zickfeld.

The geographer wrote the paper with Damon Matthews, a University of Concordia associate professor at the Department of Geography, Planning and Environment.

The duo used an earth system climate model developed by the University of Victoria to study the impact of greenhouse gas and aerosol emissions on the world’s climate. The study was based on emission levels that are consistent with data from the 2007 report of the Intergovernmental Panel on Climate Change.

The removal of aerosols from the atmosphere would cause additional global warming in the short term, if all of those emissions were removed now. “The widespread presence of aerosols in the Earth’s atmosphere is effectively acting like a solar radiation blocking blanket right now,” explains Zickfeld.

“It’s preventing the Earth’s temperature from responding to the real effects of global warming. But once that aerosol-based blanket is removed the temperature will rise.”

Due to the emission of greenhouse gases, the world’s temperature has warmed by almost 1 ° C since the beginning of the industrial era. The study finds that elimination of all emissions would lead to an additional short-term warming by 0.25 to 0.5 degrees.

“One to 1.5 degrees of may not seem like a great deal,” says Zickfeld. “But we need to realize that the warming would not be distributed equally over the globe, with mid to high latitude regions such as Canada, Alaska, northeastern Europe, Russia and northern China being most strongly affected.

“Our research shows that as a result of past emissions, a warming of at least 2 ° C will be unavoidable in those regions.”

This study is the first to find that if all greenhouse gas and aerosol emissions were halted now the Earth’s temperature would actually continue to rise by a few tenths of a degree over the next 10 years. Then it would begin to cool by a few tenths of a degree, coming down to its current level after about a century.

During the warming period the Earth’s temperature would rise to roughly 1.3-Celsius degrees higher than it was at the beginning of the industrial era.

In the northern hemisphere that peak temperature would be closer to 2 degrees higher. The reason is that the warming is not distributed equally over the globe, and is amplified at high latitudes.

“Two degrees is pretty significant,” notes Zickfeld, “when you consider the global temperature was only five degrees colder than today’s during the ice age.”

A decrease in greenhouse gases with short atmospheric lifetimes, such as methane and nitrous oxide, will cause the planet to gradually cool off after the warming phase.

The atmospheric concentration of long-lived greenhouse gases such as carbon dioxide determines the world’s long-term temperature.

This study is also the first to quantify the extent to which past greenhouse gas and aerosol emissions will warm oceans, causing them to rise. Zickfeld and Matthews found to date will lead to about a 25 centimeters sea level rise in 2200, and the sea level will continue to rise for several centuries after that date.

The study doesn’t analyse the impact of other factors, such as melting glaciers and ice sheets, on sea levels. These factors are expected to accelerate rise further.


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Citation: Warming of two degrees inevitable over Canada: study (2012, March 4) retrieved 18 June 2019 from https://phys.org/news/2012-03-degrees-inevitable-canada.html
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Mar 04, 2012
A model is something you tweak until you get the answer you want. To call the authors "researchers" is absurd.

Mar 04, 2012
Serves Canadians right for abandoning even the pretense of caring. Unfortunately others go down with them, hope you have room up there for a flood of immigrants with really big guns.

Mar 04, 2012
There are many reasons why we should question the validity of these models. For an objective discussion on this please go here http://judithcurr...part-ii/

Mar 05, 2012
Ethical hey... like Peter Gleick http://www.ocregi...bal.html Wasn't he the chair of the American Geophysical Union's Task Force on Scientific Ethics. If he was the chair what are the rest of them like? You're a very trusting man Vendicar and it's very sweet. Everyone else though should look on the internet and make up their own minds.

Mar 05, 2012
Just look at the globle temperature changes over the past 30,000 yrs. you will see huge temperature changes.
Not controlling our environment is a death sentence to the specie. We must control our environment including things from space that will impact our planet eventually.
So all this crap about who is right and who is lying is wasted nonsense!
As it turns out the Scientist have less reason to lie than any other group, and also have presented better data. As well of having a better record throughout history.
The energy plans for the future are ridicules and in no way will be enough to accomplish our survival.
Some of you that are reading this message are young enough to really be impacted by the lack of regard by your older so called "Leaders" about your future.
I doubt if anything significant will be done about addressing these problems unless you young people put the pressure on BIG TIME RIGHT NOW. So get on the net like never before. It is your lives that will be impacted.

Mar 05, 2012
A more accurate title for this piece would be
"Warming of two degrees inevitable over Canada: If our models are right"
Have they ever been right? Well..... no.... but... we spent a lot of time on them. Modelers are artists. They're not scientists because there's no testable hypothesis and peer review doesn't really happen. Real review would require the reviewer going through the entire code which would take as long to do as creating it in the first place, Artists create. They're allowed to lie because they created the illusion in the first place. We should celebrate these guys for their imagination.

Mar 05, 2012
LOL. . .scientists are as truthful or unethical liars as is necessary
-Says the farmer with 40 acres of sweet sorghum which he is going to turn into ethanol by magic.
. . .only with college degrees and research grants.
Says the poster flooder who thinks these things are not necessary to do physics, climate science, metallurgy, etc. Only the power of the wounded brain and 300 lbs of dumbass. LOL.

Mar 05, 2012
@rubberman So did the temperature rise exponentially before the Roman and Medieval warm periods because of methane forcing as I suppose the permafrost melted then too? Perhaps.... but the human population seemed to do pretty well out of it. Increased temperature may cause more evaporation and more clouds. The increased albedo of clouds forces the temperature back down. I'm guessing their model didn't account for either let alone cosmic rays and cloud formation..

Mar 06, 2012
You are not one of these guys by any chance rubberman?http://www.green-agenda.com/

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