Avoiding catastrophic global warming requires stabilizing carbon dioxide concentrations, not emissions. Studies find that many, if not most, people are confused about this, including highly educated graduate students. I have personally found even well informed people are confused on this point and its crucial implications.
We need to cut emissions 50 to 80 percent below current levels just to stop concentrations from rising. And global temperatures will not be stabilized for decades after concentrations are stabilized. And of course, the ice sheets may not stop disintegrating for decades -- and if we dawdle too long, centuries -- after temperatures stabilize. That is why we must act now if we want to have any reasonable hope of averting catastrophe.
One 2007 MIT study, "Understanding Public Complacency About Climate Change: Adults' mental models of climate change violate conservation of matter," concluded "Low public support for mitigation policies may be based more on misconceptions of climate dynamics than high discount rates or uncertainty about the risks of harmful climate change."
Here is a great video clarifying the issue, which you can send to folks. It is narrated by my friend Andrew Jones:
If you want to play the simulation itself, go here. They make use of the bathtub analogy: While atmospheric concentrations (the total stock of CO2 already in the air) might be thought of as the water level in the bathtub, emissions (the yearly new flow into the air) are the rate of water flowing into a bathtub.
As John Sterman, Director of the MIT System Dynamics Group at the Sloan School of Management, noted, Bush cleverly plays into the public's confusion with his SOTU line:
... let us complete an international agreement that has the potential to slow, stop, and eventually reverse the growth of greenhouse gases.
As Sterman writes, "So the SOTU still reflects deliberate and careful use of language to make delay sound like action."
I recommend reading the entire MIT study, whose lead author is John Sterman. Here is the abstract:
Public attitudes about climate change reveal a contradiction. Surveys show most Americans believe climate change poses serious risks but also that reductions in greenhouse gas (GHG) emissions sufficient to stabilize atmospheric GHG concentrations or net radiative forcing can be deferred until there is greater evidence that climate change is harmful. US policymakers likewise argue it is prudent to wait and see whether climate change will cause substantial economic harm before undertaking policies to reduce emissions. Such wait-and-see policies erroneously presume climate change can be reversed quickly should harm become evident, underestimating substantial delays in the climate's response to anthropogenic forcing. We report experiments with highly educated adults -- graduate students at MIT -- showing widespread misunderstanding of the fundamental stock and flow relationships, including mass balance principles, that lead to long response delays. GHG emissions are now about twice the rate of GHG removal from the atmosphere. GHG concentrations will therefore continue to rise even if emissions fall, stabilizing only when emissions equal removal. In contrast, results show most subjects believe atmospheric GHG concentrations can be stabilized while emissions into the atmosphere continuously exceed the removal of GHGs from it. These beliefs -- analogous to arguing a bathtub filled faster than it drains will never overflow -- support wait-and-see policies but violate conservation of matter. Low public support for mitigation policies may be based more on misconceptions of climate dynamics than high discount rates or uncertainty about the risks of harmful climate change.
This post was created for ClimateProgress.org, a project of the Center for American Progress Action Fund.
Natural gas as a near-term CO2 mitigation strategy
Comments
View as Flat
Matt G Posted 9:11 am
01 Feb 2008
This definatly tops the list of best-named graduate studies.
/and eventually reverse the growth of greenhouse gases/
That explains a lot. Maybe GW isn't an evil power-hungry oil man, he just doesn't understand global warming. Maybe we all just forgot to explain it to him. Can someone send him the video?
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Peter Donovan Posted 10:07 am
01 Feb 2008
IPCC fourth assessment FAQ, 2007
http://www.ipcc.ch/pdf/assessment-report/ar4/wg1/ar4-wg1- ...
So, if we don't burn another gallon of gas after 2007, we only get down to about 1985 levels by 2100. (According to the same FAQ, with 100% reductions today, by 2200 we get down to about 1978 atmospheric CO2 levels.) The strategy of CO2 emissions reductions alone, even if we actually pursue it, has NO LEVERAGE. Might as well try to drive a wood screw with a hammer. We're not going to even notice the difference, and meantime the oceans continue to heat.
The only leverage it has is on our feelings of guilt.
Paralysis and continued unresolved conflict are the natural result of the routine advocacy of ineffective solutions.
If we want to address climate change, technology or the regulation of it is not going to be enough. We will have to understand things like soil, how biospheric processes work.
http://soilcarboncoalition.org
managingwholes.net
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JMG Posted 12:08 pm
01 Feb 2008
Save the world: Reduce greenhouse gas emissions 5% annually.
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Sam Wells Posted 2:39 pm
01 Feb 2008
What I do know is that the typical planetary boundary layer that captures most of the pollution is maybe 3,000 to 5,000 feet above ground level in the early afternoon but often low at night, and there is another "transport layer" over that, known as the tropopause. The transport layer is how we get Sahara dust in Texas and pollution from China on the upper West Coast.
Obviously we know that CO2 cannot mix uniformly into the entire atmosphere all the way up to the stratosphere. This throws a subtle twist into the "concentration versus emissions" discussion. I just thought I would note that industrial, geogenic, and biogenic plumes are where it is at.
-sammie
Onward through the fog
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trock Posted 12:39 am
02 Feb 2008
The plan is to go to plants that will put carbon in the soil. Perennials grasses for the most part do this. Using grasses that we could also use for heat or convert to fuels like the switch grass are being looked at.
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Delay And Deny Posted 10:33 am
02 Feb 2008
twice the rate of GHG removal from the atmosphere...
Removal? Wait a minute...the Party Line has always been that the CO2 that goes up into the higher layers of atmosphere is "special" and can't be removed (because it's out of reach of the biosphere...or whatever).
Now all of sudden we're given a ratio of 2:1 as in the rate of "removal" is half that of the addition.
So, what is this new found mechanism of "removal" that is suddenly entering the public-speak of AGW fanatics?
Restore the Kuomintang!
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Sam Wells Posted 2:20 pm
02 Feb 2008
78% inert nitrogen
21% oxygen
--
99%
Everything else is less than 1%. Given such low concentrations, all other gases are considered "trace gases" that can increase of decrease based on inputs and removal mechanisms. For example CO2 is about 0.4% of sampled air and such trace gases are often measured in parts per million. Therefore, what seems like a very small change in trace gas levels may have dramatic effects on health, visibility, climate forcing, and so forth. To refresh your mind, in the Industrial Revolution a century ago CO2 was at about 280 ppm; now it is at about 370 ppm.
All gases including nitrogen and oxygen recirculate but it is the trace gases, especially toxic and climate change ones, that we watch the most because small changes in PPM can have such huge impacts.
There are emission releases and there are removal mechanisms. CO2 is fairly stable and will not react chemically, photochemically, or form particulate. That is an important point because most trace gases have an "atmospheric fate" of less than a second to years, with CO2 lasting being pretty much forever.
Thus scrubbing by rain and mixing into the stratosphere are the only pathways for removal besides the fact that photosynthetic plants metabolize CO2. The stratospheric mechanism is mostly conjectural on my part and not a fact. For example, a volcano can inject a plume as high to 50,000 feet into the atmosphere so exchanges with the middle atmosphere are not common and may be freakish, but so occur. Large thunderstorms and powerful hurricanes can attain such heights as well, although recordings of much more than 50,000 feet are very few. Vertical exchange does occur, and is why ozone depleting compounds were phased out many years ago.
To deny that trace gases don't recirculate in the environment is real stupid, though. Whoever said that? /sam
Onward through the fog
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mihan Posted 12:20 am
03 Feb 2008
CO2 gain/year=CO2 input/year - CO2 output/year
If you want CO2 levels to be constant, the input and output must be the same; if you want CO2 levels to decrease, the output must be higher than the input. Currently, input is about half of the output. The output is by plants and chemical/weathering processes (google "carbon cycle"); Sam correctly says that this mostly occurs in the lower atmosphere but inexplicably says that it's "obvious" that CO2 cannot be well mixed into the stratosphere, which is neither obvious nor true.
The real problem is that it would be wrong to conclude that we simply need to cut CO2 input in half (to equal current output), because a lower CO2 concentration in the atmosphere will make for a reduced output.
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Sam Wells Posted 4:07 am
03 Feb 2008
And us Americans started it (not me!).
See, historically the CO2 levels were 280 ppm a century ago when things were fairly balanced and man-made emissions were not as pronounced. One hundred years later things are unbalanced because man-made emissions have increased so much and biogenic removal has if anything become weakened.
So pray tell, how can trees reduce man-made emissions? True, a plume from a highway might pass a cluster of trees, absorbing some CO2, but the the net analysis, the big picture, that was a huge mistake.
And look, everybody is selling "credits" to plant freakin' trees! It is beyond all scientific understanding and smacks of shamanism, political hucksterism, and the worst sort of voodoo I have ever heard, /sam
Onward through the fog
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sindark Posted 5:17 am
03 Feb 2008
What is less commonly recognized is how ambitious a goal this is. The difficulty of the goal is closely connected to climate sensitivity: the "equilibrium change in global mean surface temperature following a doubling of the atmospheric (equivalent) CO2 concentration." According to the Intergovernmental Panel on Climate Change, this is: "likely to be in the range 2 to 4.5°C with a best estimate of about 3°C, and is very unlikely to be less than 1.5°C. Values substantially higher than 4.5°C cannot be excluded, but agreement of models with observations is not as good for those values."
Taking their most likely value, 3°C, the implication is that we cannot allow the doubling of global greenhouse gas concentrations. Before the Industrial Revolution, carbon dioxide concentrations were about 280ppm. Today, they are about 380ppm.
Based on the IPCC's conclusions, stabilizing greenhouse gas levels at 450ppm only produces a 50% chance of staying below 2°C of warming. In order to have a relative high chance of success, levels need to be stabilized below 400ppm. The Stern Review's economic projections are based around stabilization between 450 and 500ppm. Stabilizing lower could be quite a lot more expensive.
Finally, there is considerable uncertainty about climate sensitivity itself. Largely, this is the consequence of feedback loops within the climate. If feedbacks are so strong that climate sensitivity is greater than 3°C, it is possible that current GHG concentrations are sufficient to breach the 2°C target for total warming. Some people argue that climatic sensitivity is so uncertain that temperature-based targets are useless.
a sibilant intake of breath
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Sam Wells Posted 7:02 am
03 Feb 2008
I will go further to say that concentration-based methods are also a huge problem, since there are lag response times between emissions input and average ambient concentrations.
We need to recognize that even emissions, in tons or terra-grams, are not so perfect either. To say the art of the emissions inventory is the be-all-end-all is rather silly. However, we should work on reducing man-made CO2 emissions as fast as we can just to offset growth, and achieve further reductions as well. As noted by many here at Grist, these kinds of actions will take very deep cuts.
In a somewhat smug maneuver, EIA and EPA are claiming CO2 reductions for 2006 as compared to 2005. A little research shows that this is complete crap, especially with international shipping and military fuel uses which increased:
"Because the definition of energy consumption by the IPCC excludes international bunker fuels from the statistics of all countries, emissions from international bunker fuels are subtracted from the U.S. total. Similarly, because the IPCC excludes emissions from military bunker fuels from national totals, they are subtracted from the U.S. total."
You read it here on Grist.
-sammie
Onward through the fog
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