Soot 'contributes twice as much to global warming than thought'

Washington, January 16 (ANI): In addition to causing smoggy skies and chronic coughs, soot turns out to be the number two contributor to global warming and only second only to carbon dioxide, researchers say.

The four-year assessment by an international panel concludes that black carbon, the soot particles in smoke and smog, contributes about twice as much to global warming as previously estimated, even by the 2007 Intergovernmental Panel on Climate Change.

"We were surprised at its potential contribution to climate," Sarah Doherty, one of the lead co-ordinating lead authors of the study from the University of Washington, said.

The silver lining may be that controlling these emissions can deliver more immediate climate benefits than trying to control carbon dioxide, she said.

Some previous research had hinted that models were underestimating black-carbon emissions, Doherty said, from such things as open burning of forests, crops and grasslands, and from energy-related emissions in Southeast Asia and East Asia.

Black carbon's role in climate is complex. Dark particles in the air work to shade the Earth's surface while warming the atmosphere. Black carbon that settles on the surface of snow and ice darkens the surface to absorb more sunlight and increase melting.

Finally, soot particles influence cloud formation in ways that can have either a cooling or warming impact.

The report surveyed past studies and included new research to quantify the sources of black carbon and better understand its overall effect on the climate.

Doherty was executive director of the International Global Atmospheric Chemistry Projectin 2009 when policy groups were seeking better information on the benefits of reducing black-carbon emissions.

The research team undertook a comprehensive assessment, funded by IGAC and the U.S. National Oceanic and Atmospheric Administration.

"Because of a lack of action to reduce carbon dioxide emissions, the policy community is asking what else we can do, particularly to help places like the Arctic that are melting much more quickly than we had anticipated," Doherty said.

"We hope reducing black-carbon emissions buys us some time. But it doesn't replace cutting back on CO2 emissions," she said.

While carbon dioxide has a half-life of 100 years, black carbon stays in the atmosphere for only a few days.

The authors investigated various sources of black carbon to see which reductions might have the most short-term cooling impact.

Regulating emissions from diesel engines followed by replacing some wood- and coal-burning household stoves, authors find, would have the greatest immediate cooling impact.

"If you're just thinking about impact on climate, you would want to be strategic about which sources you cut back on," Doherty said.

"We looked at the overall impact because some of these sources also emit associated particles that can have counteracting effects," she said.

The report incorporates data that Doherty and co-author Stephen Warren, a UW professor of atmospheric sciences, gathered between 2007 and 2009 to measure soot on Arctic snow. Calculating black carbon deposits in the Arctic is difficult, so data are essential for testing and correcting models.

The study has been published online in the Journal of Geophysical Research-Atmospheres. (ANI)

Matches

MORE TOP STORIES TODAY

Duminy steals first win for Delhi

Duminy steals first win for Delhi

Furious fifties by Duminy and Dinesh Karthik end a long losing streak for the Daredevils. More »

AB, Parthiv seal Bangalore's second win

AB, Parthiv seal Bangalore's second win

Royal Challengers overcame a stutter to cruise to the small target they were set by Mumbai Indians. More »

Glenn Maxwell carves his parallel universe

Glenn Maxwell carves his parallel universe

Glenn Maxwell seems to project an icy disdain when at the crease. Match situations rarely faze him and the bubble in which he plays excludes everyone … More »

Srinivasan can attend BCCI meeting

Srinivasan can attend BCCI meeting

His status as president of TNCA makes him eligible to attend the Working Committee meeting on Sunday. More »

No way back for Pietersen: ECB

No way back for Pietersen: ECB

Kevin Pietersen's hopes of reviving his international career appeared to end Saturday when ECB managing director Paul Downton said there was 'no way back'… More »

[REWIND] The world record that nearly wasn't

[REWIND] The world record that nearly wasn't

Twenty years ago this week, Brian Lara became Test cricket's highest scorer, but he almost didn't make it. More »

Moores gets second stint as England coach

Moores gets second stint as England coach

In a two-year spell from 2007 to 2009, the 51-year-old Moores led England in seven Test series. More »

Bangladesh senior players to see shrink

Bangladesh senior players to see shrink

Bangladesh's senior players will have three sessions with a psychological skill development coach later this month More »

BCCI is not anybody’s property — Dalmiya

BCCI is not anybody’s property — Dalmiya

Dalmiya feels that Srinivasan’s ‘power hungry’ attitude isn’t helping matters. More »

KP ridicules idea of day-night Tests

KP ridicules idea of day-night Tests

Kevin Pietersen has ridiculed the idea of day-night Test cricket, saying the game would be so different to proper Test cricket that we will need a whole… More »

Rajasthan edge low-scoring thriller

Rajasthan edge low-scoring thriller

The bowlers restricted Hyderabad to 133 for 6 before Rahane and Binny took Rajasthan over the line. More »

Tough for bowlers: Saeed Ajmal

Tough for bowlers: Saeed Ajmal

The 36-year-old believes the T20 format and rule changes in 50-over matches have made a real difference. More »

Maxwell blitz takes Punjab home

Maxwell blitz takes Punjab home

The Kings XI batsman blasted a 43-ball 95 to help his team pull off a massive chase against Chennai Super Kings. More »

BCCI members want independent probe

BCCI members want independent probe

The board members are realising after the Supreme Court's observations that something has to be done — IS Bindra More »

'BCCI lacks leaders to take on Srini'

'BCCI lacks leaders to take on Srini'

Two former BCCI presidents, Shashank Manohar and Jagmohan Dalmiya, have reacted strongly to the news of the BCCI calling an emergent meeting on Sunday… More »

Delhi look for first points against confident Kolkata

Delhi look for first points against confident Kolkata

Preview — The threat of Sunil Narine looms large again. More »

Bangalore vs Mumbai: A battle of the big-hitters

Bangalore vs Mumbai: A battle of the big-hitters

Preview — Given the firepower in both line-ups, Dubai crowd may see another high-scorer More »

Yuvraj tees off to Sharjah's delight

Yuvraj tees off to Sharjah's delight

Yuvraj Singh was hardly convincing to begin with against Delhi, but a big dose of crowd support and a helping of poor bowling meant he had the opportunity… More »

Stressed Trott stands down again

Stressed Trott stands down again

The England and Wales Cricket Board (ECB) on Friday confirmed that batsman Jonathan Trott is to take another break from all cricket with immediate eff… More »

PCB starts another coach hunt

PCB starts another coach hunt

The PCB has decided to not extend the contracts of head coach Moin Khan, fielding coach Shoaib Mohammad and batting consultant Zaheer Abbas, and has invited… More »

Fiery star Stokes bids to curb his temper

Fiery star Stokes bids to curb his temper

England all-rounder Ben Stokes admits he must keep his anger under control if he is to end his international exile. More »

Bangalore's arsenal blazes to victory

Bangalore's arsenal blazes to victory

Yuvraj Singh was back to his best in his first match for Royal Challengers Bangalore. More »

Pakistan cricketers face probe

Pakistan cricketers face probe

Pakistani cricket authorities have launched an investigation after a number of current international stars played in exhibition matches in the United States… More »

BCCI to meet before next court hearing

BCCI to meet before next court hearing

The BCCI will hold an emergent working committee meeting on April 20 to discuss the future course of action with regard to the Supreme Court hearing concerning… More »