International study identifies 14 key measures to reduce methane and black carbon emissions; reduction in projected global mean warming of ~0.5 °C by 2050
13 January 2012
A study by an international team of researchers, led by Drew Shindell of NASA’s Goddard Institute for Space Studies (GISS) in New York City, has identified 14 measures targeting methane and black carbon (BC) emissions that could reduce projected global mean warming ~0.5°C (~0.9 °F) by 2050, as well as improving human health and agriculture. Their paper is published in the journal Science.
Black carbon, a product of burning fossil fuels or biomass such as wood or dung, can worsen a number of respiratory and cardiovascular diseases. The small particles also absorb radiation from the sun causing the atmosphere to warm and rainfall patterns to shift. In addition, they darken ice and snow, reducing their reflectivity and hastening global warming. Methane is both a potent greenhouse gas and an important precursor to ground-level ozone. Ozone, a key component of smog and also a greenhouse gas, damages crops and human health.
Tropospheric ozone and black carbon (BC) contribute to degraded air quality and global warming. While carbon dioxide is the primary driver of global warming over the long term, limiting black carbon and methane are complementary actions that would have a more immediate impact because these two pollutants circulate out of the atmosphere more quickly.
The team considered about 400 emission control measures to reduce these pollutants by using current technology and experience. In addition to the reduction in warming, the researchers estimated that implementing the 14 measures would avoid 0.7 to 4.7 million annual premature deaths from outdoor air pollution and increase annual crop yields by 30 to 135 million metric tons due to ozone reductions in 2030 and beyond.
Tropospheric ozone and black carbon (BC) are the only two agents known to cause both warming and degraded air quality. Although all emissions of BC or ozone precursors [including methane (CH4)] degrade air quality, and studies document the climate effects of total anthropogenic BC and tropospheric ozone, published literature is inadequate to address many policy-relevant climate questions regarding these pollutants because emissions of ozone precursors have multiple cooling and warming effects, whereas BC is emitted along with other particles that cause cooling, making the net effects of real-world emissions changes obscure. Such information is needed, however, because multiple stakeholders are interested in mitigating climate change via control of non–carbon dioxide (CO2)–forcing agents such as BC, including the G8 nations (L’Aquila Summit, 2009) and the Arctic Council (Nuuk Declaration, 2011).
Here, we show that implementing specific practical emissions reductions chosen to maximize climate benefits would have important “win-win” benefits for near-term climate, human health, agriculture, and the cryosphere, with magnitudes that vary strongly across regions.—Shindell et al.
The team considered the 400 control measures based on technologies evaluated by the International Institute for Applied Systems Analysis in Laxenburg, Austria, and then focused on 14 measures with the greatest climate benefit. All 14 would curb the release of either black carbon or methane.
The model estimated potential worldwide emissions reductions of particulate and gaseous species on the basis of available real-world data on reduction efficiencies of these measures where they have been applied already and examined the impact of full implementation everywhere by 2030. Their potential climate impact was assessed by using published global warming potential (GWP) values for each pollutant affected. All emissions control measures are assumed to improve air quality. We then selected measures that both mitigate warming and improve air quality, ranked by climate impact.
If enhanced air quality had been paramount, the selected measures would be quite different [for example, measures primarily reducing sulfur dioxide (SO2) emissions improve air quality but may increase warming]. The screening revealed that the top 14 measures realized nearly 90% of the maximum reduction in net GWP. Seven measures target CH4 emissions, covering coal mining, oil and gas production, long-distance gas transmission, municipal waste and landfills, wastewater, livestock manure, and rice paddies. The others target emissions from incomplete combustion and include technical measures (set “Tech”), covering diesel vehicles, clean-burning biomass stoves, brick kilns, and coke ovens, as well as primarily regulatory measures (set “Reg”), including banning agricultural waste burning, eliminating high-emitting vehicles, and providing modern cooking and heating. We refer to these seven as “BC measures,” although in practice, we consider all co-emitted species.—Shindell et al.
|Methane and BC measures identified as mitigating climate change and improving air quality which have a large emission reduction potential. Shindell et al., Supplementary material. Click to enlarge.|
The team concluded that these control measures would provide the greatest protection against global warming to Russia, Tajikistan and Kyrgyzstan—countries with large areas of snow or ice cover. Iran, Pakistan and Jordan would experience the most improvement in agricultural production. Southern Asia and the Sahel region of Africa would see the most beneficial changes to precipitation patterns. The south Asian countries of India, Bangladesh and Nepal would see the biggest reductions in premature deaths.
Drew Shindell, Johan C. I. Kuylenstierna, Elisabetta Vignati, Rita van Dingenen, Markus Amann, Zbigniew Klimont, Susan C. Anenberg, Nicholas Muller, Greet Janssens-Maenhout, Frank Raes, Joel Schwartz, Greg Faluvegi, Luca Pozzoli, Kaarle Kupiainen, Lena Höglund-Isaksson, Lisa Emberson, David Streets, V. Ramanathan, Kevin Hicks, N. T. Kim Oanh, George Milly, Martin Williams, Volodymyr Demkine, and David Fowler (2012) Simultaneously Mitigating Near-Term Climate Change and Improving Human Health and Food Security. Science 335 (6065), 183-189. doi: 10.1126/science.1210026
Naysayers and the (R) majority will not believe nor support such factual studies because of their vested interests, religious beliefs and/or their knowledge gap. Consequently, not much will be done and we will knowingly continue harm and kill ourselves and our children with fossil fuels. That's how smart we have become!
Posted by: HarveyD | 13 January 2012 at 08:27 AM
Reducing methane and particulate emissions is the low-hanging fruit of AGW mitigation--it pays for itself in the short term. Considering the immediate benefits of these policies, it should be a downhill push to get them implemented. Somehow we need to work towards international agreements to push for these very achievable goals.
Posted by: Nick Lyons | 13 January 2012 at 11:17 AM
You never know, these problems are a lot simper to solve (or make progress with) than reducing CO2 emissions, so people might well have a go at them.
Even countries like China and India might go for it as they suffer badly from GW.
They might throw their hands up in the air about burning coal, but have a go at particulates and methane.
Posted by: mahonj | 13 January 2012 at 11:47 AM
Once we quantify the benzene in oil products and the mercury in coal burning, we will come up with a health care bill that neither of those industries pays a dime on, but we can give them tax subsidies every day.
Posted by: SJC | 13 January 2012 at 07:35 PM
important if one assumes AGW is significant, apparently the science is not settled yet.. otherwise why spend all that effort to obfuscate by the Warmists.. read the new batch of climategate emails.
Posted by: Herm | 13 January 2012 at 08:08 PM
It amuses me that the denialists not only resort to make-up slurs like "warmists", but their disordered thinking processes go all the way down to semi-coherent sentences.
Posted by: Engineer-Poet | 14 January 2012 at 08:35 AM
@Herm: Even if AGW didn't exist, the health and economic benefits from reducing methane and particulate emissions far outweigh the costs of the reductions. The only reasons to resist these changes are either ignorance of the benefits or an unwillingness on the part of individual polluters to start paying for the externalized costs they are currently inflicting on others.
Posted by: Nick Lyons | 14 January 2012 at 11:15 AM
read the new batch of climategate emails
We would if there were any. In fact this "new batch" are just 'not previously released' emails from the old batch. And the reason they were not released in the original flap is because the out of context quote mining for them was even less convincing than for those that hit the headlines the first time around.
Just looking at the dates on this "new batch of climategate emails" should have clued you in: They were on the server when 3 separate teams looked at everything the CRU had and found NO wrongdoing. You can be assured those investigators read this "new batch of climategate emails" back then, so if there was anything to them why did they still clear the CRU?
Posted by: ai_vin | 15 January 2012 at 08:01 AM
I reside in the foothills of the Sierra Nevada mountains in California where many of us use woodstoves for heat(supplemental at least).Seems like there would be a great market for aftermarket catalytic converters that would be supplemented heated by electricity to stay in their proper opperating range.This would work 95% of the time when we have electricity, and allow people to keep their older woodstoves. Anybody know of or working on this?I'm assuming of course that a catalyst would dramatically reduce particulate emissions. Richard
Posted by: Richard Burton | 15 January 2012 at 01:04 PM
Many woodstoves were built using catalysts, I have one, and there are aftermarket catalysts that can be fitted in the flue pipe. However the catalysts are expensive and do need occasional cleaning and replacing. I think the newer stoves use a non catalyst "after burn" chamber to superheat the air and achieve the same results.
Posted by: JRP3 | 15 January 2012 at 01:39 PM
And Richard Nixon was given a "pardon."
Posted by: Reel$$ | 15 January 2012 at 01:51 PM
Please note GCC censors are now deleting any post with referral to Low Energy and Nuclear Reactions. Apparently this is such a "hot" topic they cannot bear to see it mentioned. Ouch!
Posted by: Reel$$ | 15 January 2012 at 02:34 PM
Or maybe you just abused the privilege once too many times.
Posted by: ai_vin | 15 January 2012 at 02:38 PM
Is it a "privilege" to tell the truth? Perhaps in a fascist state.
Posted by: Reel$$ | 16 January 2012 at 05:27 PM
Why don't you try telling the truth for a while and see what happens?
You can start with the truth that the "NASA endorsement" you've been touting turns out to be one guy's after-hours ruminations, and even he's much more skeptical than you've been letting on.
Posted by: Engineer-Poet | 16 January 2012 at 08:13 PM
Finally I can make out some numbers in the graphic above.
Posted by: E-Biker | 17 January 2012 at 12:21 PM
Golly EP, you reveal yourself to be the censoring culprit. How un-American of you, (but then you're not an American are you?)
No, EP, the NASA video that publicly acknowledges for the entire Agency the fact, science and veracity of the excess heat effect - is an attempt to avoid the sh*tstorm headed at all scientists and politicos involved in retarding development of this life-saving technology.
House cleaning EP. You ready?
Posted by: Reel$$ | 18 January 2012 at 07:07 PM
I'm 100% red-blooded American, standing up for Truth and Justice. Truth means preferring facts over falsehoods, and justice means giving both the good and the bad what they deserve.
Here's some Truth about Rossi that you don't want anyone to see:In other words, Rossi won't prove to the public that his device actually does what he claims. He's a fraud, so it's no wonder you like him so much: you have that in common.
Posted by: Engineer-Poet | 31 January 2012 at 02:55 PM