Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Swedish and Indian researchers constrain the sources of climate- and health-afflicting soot pollution over South Asia

23.01.2009
A gigantic brownish haze from various burning and combustion processes is blanketing India and surrounding land and oceans during the winter season.

This soot-laden Brown Cloud is affecting South Asian climate as much or more than carbon dioxide and cause premature deaths of 100 000s annually, yet its sources have been poorly understood.

In this week's issue of Science Örjan Gustafsson and colleagues at Stockholm University and in India use a novel carbon-14 method to constrain that two-thirds of the soot particles are from biomass combustion such as in household cooking and in slash-and-burn agriculture.

Brown Clouds, covering large parts of South and East Asia, originate from burning of wood, dung and crop residue as well as from industrial processes and traffic. Previous studies had left it unclear as to the relative source contributions of biomass versus fossil fuel combustion.

Combustion-derived soot particles are key components of the Brown Cloud in Asia. The soot absorbs sunlight and thereby heats the atmosphere while cooling Earth's surface by shading. The net effect of soot on climate warming in South Asia is rivaling that of carbon dioxide.

The Swedish-Indian team managed to address the uncertainty of the soot sources by the first-ever microscale measurements of natural C-14 (half-life of 5700 years) of atmospheric soot particles intercepted on a mountain top in western India and outside SW India on the Hanimaadhoo island of the Maldives. Their results, presented in the Science article, demonstrated that the brown cloud soot was persistently about two-thirds from burning of contemporary biomass (C-14 "alive") and one-third from fossil fuel combustion (C-14 "dead").

These findings provide a direction for actions to curb emissions of Brown Clouds. Örjan Gustafsson, a professor of biogeochemistry at Stockholm University and leader of the study, says that the clear message is that efforts should not be limited to car traffic and coal-fired power plants but calls on fighting poverty and spreading India-appropriate green technology to limit emissions from small-scale biomass burning. "More households in South Asia need to be given the possibility to cook food and get heating without using open fires of wood and dung" says Gustafsson.

The rewards of decreasing soot emissions from biomass combustion may be rapid and sizeable. Globally, soot accounts for roughly half the warming potential of carbon dioxide. While carbon dioxide levels in the atmosphere respond on a sluggish 100 yr timescale to reductions in emissions, Brown Cloud soot particles only reside in the atmosphere for days-weeks raising the hope for a rapid response of the climate system.

Several additional positive effects would result from a reduction on Brown Cloud soot particle emissions. A recent report by the United Nations Environment Program, Atmospheric Brown Clouds: Regional Assessment Report with Focus on Asia (http://www.rrcap.unep.org/abc/impact/) outlines severe effects including melting of the Himalayan glaciers and weather systems becoming more extreme. The Brown Cloud is also having impact on agriculture and air quality in Asia. Henning Rodhe, a professor of chemical meteorology at Stockholm University, vice-chair of the UNEP Atmospheric Brown Cloud Program and also co-author of the Science article, states that the report finds that 340 000 people in China and India die each year from cardiovascular and respiratory diseases that can be traced to human-induced emissions of combustion particles. "The impact on health alone is a strong reason to reduce these Brown Clouds" says Rodhe.

Further information
Professor Örjan Gustafsson, Department of Applied Environmental Science and the Bert Bolin Climate Research Centre, Stockholm University orjan.gustafsson@itm.su.se or +46-70-3247317.
Professor Henning Rodhe, Department of Meteorology and the Bert Bolin Climate Research Centre, Stockholm University rodhe@misu.su.se or +46-8-164342.

Reporters may contact the AAAS-Science SciPak team at +1-202-326-6440 or scipak@aaas.org to receive an official version of the Science paper during the embargo.

Pressofficer: Maria Erlandsson; maria.erlandssson@kommunikation.su.se;
+46-70 230 88 91
For pictures: Contact Stockholm University Press Office at +46 (0)8-164090 or press@su.se

Maria Erlandsson | idw
Further information:
http://www.rrcap.unep.org/abc/impact/
http://www.su.se
http://www.vr.se

More articles from Ecology, The Environment and Conservation:

nachricht Scientists produce a new roadmap for guiding development & conservation in the Amazon
09.12.2016 | Wildlife Conservation Society

nachricht Successful calculation of human and natural influence on cloud formation
04.11.2016 | Goethe-Universität Frankfurt am Main

All articles from Ecology, The Environment and Conservation >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Electron highway inside crystal

Physicists of the University of Würzburg have made an astonishing discovery in a specific type of topological insulators. The effect is due to the structure of the materials used. The researchers have now published their work in the journal Science.

Topological insulators are currently the hot topic in physics according to the newspaper Neue Zürcher Zeitung. Only a few weeks ago, their importance was...

Im Focus: Significantly more productivity in USP lasers

In recent years, lasers with ultrashort pulses (USP) down to the femtosecond range have become established on an industrial scale. They could advance some applications with the much-lauded “cold ablation” – if that meant they would then achieve more throughput. A new generation of process engineering that will address this issue in particular will be discussed at the “4th UKP Workshop – Ultrafast Laser Technology” in April 2017.

Even back in the 1990s, scientists were comparing materials processing with nanosecond, picosecond and femtosesecond pulses. The result was surprising:...

Im Focus: Shape matters when light meets atom

Mapping the interaction of a single atom with a single photon may inform design of quantum devices

Have you ever wondered how you see the world? Vision is about photons of light, which are packets of energy, interacting with the atoms or molecules in what...

Im Focus: Novel silicon etching technique crafts 3-D gradient refractive index micro-optics

A multi-institutional research collaboration has created a novel approach for fabricating three-dimensional micro-optics through the shape-defined formation of porous silicon (PSi), with broad impacts in integrated optoelectronics, imaging, and photovoltaics.

Working with colleagues at Stanford and The Dow Chemical Company, researchers at the University of Illinois at Urbana-Champaign fabricated 3-D birefringent...

Im Focus: Quantum Particles Form Droplets

In experiments with magnetic atoms conducted at extremely low temperatures, scientists have demonstrated a unique phase of matter: The atoms form a new type of quantum liquid or quantum droplet state. These so called quantum droplets may preserve their form in absence of external confinement because of quantum effects. The joint team of experimental physicists from Innsbruck and theoretical physicists from Hannover report on their findings in the journal Physical Review X.

“Our Quantum droplets are in the gas phase but they still drop like a rock,” explains experimental physicist Francesca Ferlaino when talking about the...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

ICTM Conference 2017: Production technology for turbomachine manufacturing of the future

16.11.2016 | Event News

Innovation Day Laser Technology – Laser Additive Manufacturing

01.11.2016 | Event News

#IC2S2: When Social Science meets Computer Science - GESIS will host the IC2S2 conference 2017

14.10.2016 | Event News

 
Latest News

Researchers identify potentially druggable mutant p53 proteins that promote cancer growth

09.12.2016 | Life Sciences

Scientists produce a new roadmap for guiding development & conservation in the Amazon

09.12.2016 | Ecology, The Environment and Conservation

Satellites, airport visibility readings shed light on troops' exposure to air pollution

09.12.2016 | Health and Medicine

VideoLinks
B2B-VideoLinks
More VideoLinks >>>