Stabilizing climate requires near-zero carbon emissions

Now that scientists have reached a consensus that carbon dioxide emissions from human activities are the major cause of global warming, the next question is: How can we stop it" Can we just cut back on carbon, or do we need to go cold turkey" According to a new study by scientists at the Carnegie Institution, halfway measures won’t do the job. To stabilize our planet’s climate, we need to find ways to kick the carbon habit altogether.

In the study, to be published in Geophysical Research Letters, climate scientists Ken Caldeira and Damon Matthews used an Earth system model at the Carnegie Institution’s Department of Global Ecology to simulate the response of the Earth’s climate to different levels of carbon dioxide emission over the next 500 years. The model, a sophisticated computer program developed at the University of Victoria, Canada, takes into account the flow of heat between the atmosphere and oceans, as well as other factors such as the uptake of carbon dioxide by land vegetation, in its calculations.

This is the first peer-reviewed study to investigate what level of carbon dioxide emission would be needed to prevent further warming of our planet.

“Most scientific and policy discussions about avoiding climate change have centered on what emissions would be needed to stabilize greenhouse gases in the atmosphere,” says Caldeira. “But stabilizing greenhouse gases does not equate to a stable climate. We studied what emissions would be needed to stabilize climate in the foreseeable future.”

The scientists investigated how much climate changes as a result of each individual emission of carbon dioxide, and found that each increment of emission leads to another increment of warming. So, if we want to avoid additional warming, we need to avoid additional emissions.

With emissions set to zero in the simulations, the level of carbon dioxide in the atmosphere slowly fell as carbon “sinks” such as the oceans and land vegetation absorbed the gas. Surprisingly, however, the model predicted that global temperatures would remain high for at least 500 years after carbon dioxide emissions ceased.

Just as an iron skillet will stay hot and keep cooking after the stove burner’s turned off, heat held in the oceans will keep the climate warm even as the heating effect of greenhouse gases diminishes. Adding more greenhouse gases, even at a rate lower than today, would worsen the situation and the effects would persist for centuries.

"What if we were to discover tomorrow that a climate catastrophe was imminent if our planet warmed any further" To reduce emissions enough to avoid this catastrophe, we would have to cut them close to zero — and right away," says Caldeira.

Global carbon dioxide emissions and atmospheric carbon dioxide concentrations are both growing at record rates. Even if we could freeze emissions at today’s levels, atmospheric carbon dioxide concentrations would continue to increase. If we could stabilize atmospheric carbon dioxide concentrations, which would require deep cuts in emissions, the Earth would continue heating up. Matthews and Caldeira found that to prevent the Earth from heating further, carbon dioxide emissions would, effectively, need to be eliminated.

While eliminating carbon dioxide emissions may seem like a radical idea, Caldeira sees it as a feasible goal. “It is just not that hard to solve the technological challenges,” he says. “We can develop and deploy wind turbines, electric cars, and so on, and live well without damaging the environment. The future can be better than the present, but we have to take steps to start kicking the CO2 habit now, so we won't need to go cold turkey later.”

Source: Carnegie Institution

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Citation: Stabilizing climate requires near-zero carbon emissions (2008, February 15) retrieved 16 July 2019 from
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Feb 15, 2008
How does the Chicken Little Church of Consensus explain that the Southern Hemisphere is 0 degrees above normal?


Feb 15, 2008
I'll let others shoot holes in this waste of virtual space but, the opening line made it clear that this article has nothing to do with science. There are hundreds, if not thousands, of atmospheric scientists that would disagree with that premise. That such an idea would make an appearance here doesn't speak well for the editors.

Feb 15, 2008
How do they explain the vast temp. variability in the past - before we started burning and thus returning all that carbon back into the atmosphere? This is just more junk science propaganda to drum up even more pork barrel money.

Feb 15, 2008
The Southern Hemisphere has far less land mass than the northern hemisphere, with less of that land inhabited by industrialization.

Although I am not a meteoroligist, I would expect that atmosphere does not move much between the two hemispheres.

Plus, Global Warming is based on an average. If you look at a map of the mean temperature changes over the past 30-40 years, you see most of the change over the North America, specifically the U.S., and Middle Europe. Further, there are areas in the middle of the Pacific that have actually seen a decrease in mean temperatures over the last 30-40 years.

You'll notice on the map provided where most of the world's CO2 emissions are coming from.

Here is a global map of carbon dioxide emissions: CO2

Feb 15, 2008
okay, here's the map: http://ngm.nation...mate-map

Feb 16, 2008
This is the same "consensus" that the most learned authorities in the world had that Gallileo Gallilei was wrong about the moons orbiting Jupiter. It's too bad Physorg insults our intelligence with articles like this.

Feb 16, 2008
"Stabilizing climate requires near-zero carbon emissions"
The solution is simple: Believe in God and pray fervently and all will be well. God exists to answer the calling of humans. Otherwise, what God is for???

Feb 18, 2008
Way to go posters,The idiots are in the house. It is grid revv ,with periodical processes from off the planet that return on time ,every time and will abate.Actually after this process abates,it will be cooler because of the pull away of our grids energy as the "Ball" goes through. You'll see boys,then what will you do then ?? HIDE

Jun 14, 2009
Possibly if all the advocates of man-made global warming were to simply hold their breath until they are beyond turning blue, the problem would be solved. ...and think, they wouldn't be driving cars or burning electricity either.

Hyperbole aside, it is rediculous to keep framing this problem in terms of CO2 emmissions. TO THE DEGREE CO2 is a problem, it is only fossile CO2!

CO2 is a part of the normal life cycle of plants and animals. It remains in balance as long as the number of plants (algae, etc.) is balanced against the animals and their activities (like driving gas guzzeling cars.)

Everyone concerned about the high CO2 levels should be eagerly promoting green spaces with the same fervor they apply to limiting oil drilling. The fact that they don't shows they are either irrational or have motives that are not based on science.

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