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 Machine learning helps predict worldwide plant-conservation priorities
04.12.2018 | Ohio State University

nachricht From the Arctic to the tropics: researchers present a unique database on Earth’s vegetation
20.11.2018 | Martin-Luther-Universität Halle-Wittenberg

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: Researchers develop method to transfer entire 2D circuits to any smooth surface

What if a sensor sensing a thing could be part of the thing itself? Rice University engineers believe they have a two-dimensional solution to do just that.

Rice engineers led by materials scientists Pulickel Ajayan and Jun Lou have developed a method to make atom-flat sensors that seamlessly integrate with devices...

Im Focus: Three components on one chip

Scientists at the University of Stuttgart and the Karlsruhe Institute of Technology (KIT) succeed in important further development on the way to quantum Computers.

Quantum computers one day should be able to solve certain computing problems much faster than a classical computer. One of the most promising approaches is...

Im Focus: Substitute for rare earth metal oxides

New Project SNAPSTER: Novel luminescent materials by encapsulating phosphorescent metal clusters with organic liquid crystals

Nowadays energy conversion in lighting and optoelectronic devices requires the use of rare earth oxides.

Im Focus: A bit of a stretch... material that thickens as it's pulled

Scientists have discovered the first synthetic material that becomes thicker - at the molecular level - as it is stretched.

Researchers led by Dr Devesh Mistry from the University of Leeds discovered a new non-porous material that has unique and inherent "auxetic" stretching...

Im Focus: The force of the vacuum

Scientists from the Theory Department of the Max Planck Institute for the Structure and Dynamics of Matter (MPSD) at the Center for Free-Electron Laser Science (CFEL) in Hamburg have shown through theoretical calculations and computer simulations that the force between electrons and lattice distortions in an atomically thin two-dimensional superconductor can be controlled with virtual photons. This could aid the development of new superconductors for energy-saving devices and many other technical applications.

The vacuum is not empty. It may sound like magic to laypeople but it has occupied physicists since the birth of quantum mechanics.

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

New Plastics Economy Investor Forum - Meeting Point for Innovations

10.12.2018 | Event News

EGU 2019 meeting: Media registration now open

06.12.2018 | Event News

Expert Panel on the Future of HPC in Engineering

03.12.2018 | Event News

 
Latest News

Small but ver­sat­ile; key play­ers in the mar­ine ni­tro­gen cycle can util­ize cy­anate and urea

10.12.2018 | Life Sciences

New method gives microscope a boost in resolution

10.12.2018 | Physics and Astronomy

Carnegie Mellon researchers probe hydrogen bonds using new technique

10.12.2018 | Life Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>