http://www.sciencedaily.com/releases/2012/01/120112193442.htm
A new study led by [Drew Shindell of NASA's Goddard Institute for Space
Studies (GISS) in New York City], highlights 14 key air pollution
control measures that, if implemented, could slow the pace of global
warming, improve health and boost agricultural production.
The research ... finds that focusing on these measures could slow mean
global warming 0.9 ºF (0.5ºC) by 2050, increase global crop yields by up
to 135 million metric tons per season and prevent hundreds of thousands
of premature deaths each year. While all regions of the world would
benefit, countries in Asia and the Middle East would see the biggest
health and agricultural gains from emissions reductions.
...
Shindell and an international team considered about 400 control measures
based on technologies evaluated by the International Institute for
Applied Systems Analysis in Laxenburg, Austria. The new study focused on
14 measures with the greatest climate benefit. All 14 would curb the
release of either black carbon or methane, pollutants that exacerbate
climate change and damage human or plant health either directly or by
leading to ozone formation.
Shindell and his 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. The study estimates that
globally between 700,000 and 4.7 million premature deaths could be
prevented each year.
Black carbon and methane have many sources. Reducing emissions would
require that societies make multiple infrastructure upgrades. For
methane, the key strategies the scientists considered were capturing gas
escaping from coal mines and oil and natural gas facilities, as well as
reducing leakage from long-distance pipelines, preventing emissions
from city landfills, updating wastewater treatment plants, aerating rice
paddies more, and limiting emissions from manure on farms.
For black carbon, the strategies analyzed include installing filters in
diesel vehicles, keeping high-emitting vehicles off the road, upgrading
cooking stoves and boilers to cleaner burning types, installing more
efficient kilns for brick production, upgrading coke ovens and banning
agricultural burning.
The scientists used computer models developed at GISS and the Max Planck
Institute for Meteorology in Hamburg, Germany, to model the impact of
emissions reductions. The models showed widespread benefits from the
methane reduction because it is evenly distributed throughout the
atmosphere. Black carbon falls out of the atmosphere after a few days so
the benefits are stronger in certain regions, especially ones with
large amounts of snow and ice.
... The new study builds on a United Nations Environment Program/World
Meteorological Organization report, also led by Shindell, published last
year.
...
Abstract: Tropospheric ozone and black carbon (BC) contribute to both degraded air quality and global warming. We considered ~400 emission control measures to reduce these pollutants by using current technology and experience. We identified 14 measures targeting methane and BC emissions that reduce projected global mean warming ~0.5°C by 2050. This strategy avoids 0.7 to 4.7 million annual premature deaths from outdoor air pollution and increases annual crop yields by 30 to 135 million metric tons due to ozone reductions in 2030 and beyond. Benefits of methane emissions reductions are valued at $700 to $5,000 per metric ton, which is well above typical marginal abatement costs (less than $250). The selected controls target different sources and influence climate on shorter time scales than those of carbon dioxide–reduction measures. Implementing both substantially reduces the risks of crossing the 2°C threshold.
...
A 2007 Stanford University study calculated that carbon dioxide was the
No. 1 cause of man-made global warming, accounting for 48 percent of the
problem. Soot was second with 16 percent of the warming and methane was
right behind at 14 percent. But over a 20-year period, a molecule of methane or soot causes substantially more warming then a carbon dioxide molecule.
The new research won wide praise from outside scientists, including a
conservative researcher who held a top post in the George W. Bush
administration.
"So rather than focusing only on carbon dioxide emissions, where we have
to make a tradeoff with energy prices, this strategy focuses on
'win-win-win' pathways that have benefits to human health, agriculture
and stabilizing the Earth's climate," said University of Minnesota
ecology professor Jonathan Foley, who wasn't part of the study. "That's
brilliant."
John D. Graham, who oversaw regulations at the Office of Management and
Budget in the Bush administration and is now dean of public and
environmental affairs at Indiana University, said: "This is an important
study that deserves serious consideration by policy makers as well as
scientists."
The study even does a cost-benefit analysis to see if these pollution
control methods are too expensive to be anything but fantasy. They
actually pay off with benefits that are as much as ten times the value
of the costs, Shindell said. The paper calculates that as of 2030, the
pollution reduction methods would bring about $6.5 trillion in annual
benefits from fewer people dying from air pollution, less global warming
and increased crop production.
In the United States, Shindell calculates the measures would prevent
about 14,000 air pollution deaths in people older than 30 by the year
2030. About 0.8 degrees Fahrenheit of projected warming in the U.S.
would be prevented by 2050.
But health benefits would be far bigger in China and India where soot is more of a problem.
The study comes a day after the U.S. Environmental Protection Agency
released the most detailed data yet on American greenhouse gas
emissions. Of the emissions reported to the government, nearly
three-quarters came from power plants. But with methane, it's different.
Nineteen of the top 20 methane emitters were landfills.
Stanford University climate scientist Chris Field, who is a leader in
the Intergovernmental Panel on Climate Change but wasn't part of this
study, praised the study but said he worried that officials would delay
cutting back on the more prevalent carbon dioxide. Focusing solely on
methane and soot and ignoring carbon dioxide "tends to exacerbate
climate change," he said.
Also see:
by Drew Shindell 1,*, Johan C. I. Kuylenstierna 2, Elisabetta Vignati 3, Rita van Dingenen 3, Markus Amann 4, Zbigniew Klimont 4, Susan C. Anenberg 5, Nicholas Muller 6, Greet Janssens-Maenhout 3, Frank Raes 3, Joel Schwartz 7, Greg Faluvegi 1, Luca Pozzoli 3,†, Kaarle Kupiainen 4, Lena Höglund-Isaksson 4, Lisa Emberson 2, David Streets 8, V. Ramanathan 9, Kevin Hicks 2, N. T. Kim Oanh 10, George Milly 1, Martin Williams 11, Volodymyr Demkine 12 and David Fowler 13
1. NASA Goddard Institute for Space Studies and Columbia Earth Institute, Columbia University, New York, NY 10025, USA.
2. Stockholm Environment Institute, Environment Department, University of York, York YO10 5DD, UK.
3. Joint Research Centre of the European Commission, Ispra 21027, Italy.
4. International Institute for Applied Systems Analysis, Laxenburg A-2361, Austria.
5. U.S. Environmental Protection Agency, Washington, DC 20460, USA.
6. Department of Economics, Middlebury College, Middlebury, VT 05753, USA.
7. Department of Environmental Health, Harvard School of Public Health, Boston, MA 02215, USA.
8. Argonne National Laboratory, Argonne, IL 60439, USA.
9. Scripps Institute of Oceanography, University of California, San Diego, San Diego, CA 92093, USA.
10. Asian Institute of Technology, Bangkok 10400, Thailand.
11. Environmental Research Group, King’s College London, London SE1 9NH, UK.
12. United Nations Environment Programme (UNEP), Nairobi 00100, Kenya.
13. Center for Ecology and Hydrology, Midlothian EH26 0QB, UK.
† Present address: Eurasia Institute of Earth Sciences, Istanbul Technical University, Istanbul 34469, Turkey.
* To whom correspondence should be addressed. E-mail: drew.t.shindell@nasa.gov
...
Science
www.sciencemag.org
Volume 335, Number 6065; January 13, 2012: pages 183-189
