Curbing soot could slow climate change

2011-02-19 20:51
Oslo - Strict curbs on soot and ozone air pollution would limit global warming by 0.5°C in a step towards achieving tough world climate goals, a UN-backed study showed on Friday.

Stricter limits on "black carbon" soot and tropospheric ozone - a greenhouse gas that is a big component of smog - would also clear the air and so reduce human deaths and improve crop yields, especially in Asia, it said.

"Rapid implementation of proven emission reduction measures would have immediate and multiple benefits for human well-being," it said.

Proposed measures include cuts in flaring of natural gas, curbing gas leaks from pipelines and reducing methane emissions from livestock. Poor countries should make wider use of cleaner-burning stoves, and open-field burning of farm waste should be banned.

The study, backed by the UN Environment Programme, the World Meteorological Organisation and the Stockholm Environment Institute, will be reviewed by environment ministers from around the world during a meeting in Nairobi from February 21-25.

Full implementation of proposed measures to clamp down on black carbon and ozone would reduce future global warming by 0.5°C, within an estimated range from 0.2°C to 0.7°C, the report said.

Almost 200 countries agreed in Cancun, Mexico, in December to limit a rise in world temperatures to below 2°C above pre-industrial times, mainly by curbing emissions of carbon dioxide, the main greenhouse gas.

Insufficient to reach goal

Many studies show that existing pledges for cuts in greenhouse gas emissions are insufficient to reach the 2°C goal, which is viewed as a threshold to dangerous change from floods, heat waves, desertification and rising sea levels.

"This is not an alternative to carbon dioxide reductions, it's complementary," Johan Kuylenstierna, of the Stockholm Environment Institute who was scientific co-ordinator of the report, told Reuters.

The study also estimated that less air pollution could avoid 2.4 million premature human deaths a year and the annual loss of 52 million tons, or about 2%, of world production of maize, rice, soybean and wheat.

"The most substantial benefits will be felt immediately in or close to the regions where action is taken to reduce emissions, with the greatest health and crop benefits expected in Asia," it said.

Black carbon, caused by incomplete burning mainly of fossil fuels and wood, is blamed for accelerating global warming by soaking up heat from the sun. Soot can darken snow and ice when it lands, hastening a thaw such as in the Arctic or Himalayas.

Ozone is not directly emitted but is produced from precursors including methane and carbon monoxide. The troposphere is the lower atmosphere - higher up, ozone is beneficial as an ultra-violet sunshield.

Join the conversation! encourages commentary submitted via MyNews24. Contributions of 200 words or more will be considered for publication.

We reserve editorial discretion to decide what will be published.
Read our comments policy for guidelines on contributions.
Read more on:    un  |  climate change

linking and moving

2015-04-22 07:36 publishes all comments posted on articles provided that they adhere to our Comments Policy. Should you wish to report a comment for editorial review, please do so by clicking the 'Report Comment' button to the right of each comment.

Comment on this story
Comments have been closed for this article.

Inside News24


Rugby World Cup 2015

All the action from the 2015 RWC, including live coverage of all 48 matches, breaking news, fixtures, results, logs - and much more!


Rugby World Cup 2015

Habana believes in younger Boks
All Blacks ready for a 'hell of a battle'
Barnes to ref Boks, Wales clash
Brave Blossoms: 'Sport heroes of Japan'

Your incisive and innovative mind is on fire. You may be keen to explore new avenues that can help to inspire you. You more

There are new stories on the homepage. Click here to see them.


Create Profile

Creating your profile will enable you to submit photos and stories to get published on News24.

Please provide a username for your profile page:

This username must be unique, cannot be edited and will be used in the URL to your profile page across the entire network.


Location Settings

News24 allows you to edit the display of certain components based on a location. If you wish to personalise the page based on your preferences, please select a location for each component and click "Submit" in order for the changes to take affect.

Facebook Sign-In

Hi News addict,

Join the News24 Community to be involved in breaking the news.

Log in with Facebook to comment and personalise news, weather and listings.