G-8 Leaders Agree to Cut Short-Lived Greenhouse Gases

By Andrew Freedman

The Group of Eight (G-8) leading industrialized nations formally joined a coalition that is working to reduce emissions of short-lived global warming pollutants. The action took place during the G-8 summit meeting at the Camp David presidential retreat in northwest Maryland, which served as the annual gathering for the leaders of Canada, France, Germany, Italy, Japan, Russia, the U.K., and the U.S.

The Climate and Clean Air Coalition for Reducing Short-Lived Climate Pollutants, which was formed in mid-February, is now made up of 18 members in the developing and developed world. The coalition's goal is to cut emissions of climate warming pollution that acts on shorter timescales than carbon dioxide (CO2), which is the main greenhouse gas responsible for global warming.

President Barack Obama and the G-8 leaders worked on global and economic issues in the dining room of Laurel Cabin at Camp David, Md.
Official White House Photo by Pete Souza

Pollutants like black carbon, methane, and hydroflurocarbons (HFCs) help trap heat in Earth's atmosphere, warming the planet. Unlike CO2, though, they only remain in the atmosphere for a short time period, from days to weeks, in the case of black carbon, to about a decade for methane. By contrast, CO2 can remain in the atmosphere for a century or more.

In a fact sheet released on May 19, G-8 members said the reduction of short-lived global warming pollutants would “enhance our collective ambition in addressing climate change by complementing efforts to reduce CO2 emissions.”

Recent studies have identified the potential benefits of tackling short-lived global warming agents in addition to the long-lived pollutants. In a study published in January in the journal Science, researchers found that cutting black carbon emissions would reduce warming in the Himalayas and the Arctic during the next 30 years by as much as two-thirds, and would even help maintain the current South Asian monsoon. Black carbon, also known as soot, warms the air by absorbing radiation from the sun, and when it lands on snow and ice it darkens the surface, causing more melting. Another assessment from the U.N. Environment Programme also found major benefits to reducing emissions of short-lived greenhouse gases. 

Black carbon also harms public health, especially in developing countries, where wood, dung and other fuels that emit soot when burned are used for cooking. Implementing soot-reduction policies would avoid 373,000 premature deaths each year in India and China alone.

“The President's announcement puts the short-lived climate pollutant strategy where it belongs — firmly in the hands of the leaders of the world's largest economies,” said Durwood Zaelke, president of the Institute for Governance and Sustainable Development in Washington.

The G8 leaders also reaffirmed their commitment to limit global warming to less than 2°C, or 3.6°F, above pre-industrial levels. This goal, though, is looking less and less achievable, according to recent studies. Climate negotiators meeting in Bonn, Germany, this week are working to hammer out details of a process that is intended to result in a new global climate treaty by 2015, which would go into effect by 2020. However, emissions reduction pledges are still running well short of what would be needed to achieve the 2°C target.