Reducing short-lived gases is only effective as part of broader CO2 reduction strategy
A new plan to tackle short-lived pollutants may help bridge the gap between current emission reduction pledges and what is actually needed by 2020 to keep global temperatures from rising more than 2° Celsius.
At the State Department this morning, Secretary of State Hillary Rodham Clinton announced a six-country initiative designed to reduce pollutants like methane, black carbon (soot), and hydroflurocarbons (HFCs) that help speed up global warming. These pollutants are often called “climate forcers” because they push temperatures up much more quickly than carbon dioxide.
Methane, a shorter-living greenhouse gas 25 times more potent than carbon dioxide over 100-year period — and 100 more potent over a 20-year period — has contributed to roughly 50% of tropospheric ozone helping warm the planet. Soot from burning biomass and coal travels around the world and lands on ice caps and glaciers, increasing melting and preventing the reflection of sunlight. HFCs, a common refrigerant, are thousands of times more potent than carbon dioxide.
These pollutants come from inefficiently burning biomass and coal, improperly handling waste water or municipal solid waste, and poor vehicle emissions standards, among many other sources. Along with having a major impact on climate, they are also a major cause of premature deaths and crop failures.
The countries working to reduce climate forcers include Bangladesh, Canada, Ghana, Mexico, Sweden and the U.S. American officials say they will commit $10 million to the initiative, which will be run by the United Nations Environment Program (UNEP).
The initiative will follow guidelines set forward by UNEP in a report on climate forcers last November.
While the plan to reduce these pollutants is only a short-term fix, it could put the world on a path toward faster temperature reductions and provide a needed cushion as countries grapple with slow-moving international negotiations on reducing greenhouse gas emissions like carbon dioxide.
In January, Drew Shindell, a researcher with NASA’s Goddard Institute for Space Studies, found that a strong international effort to address these pollutants could slow the rise of global temperatures by a half degree celsius by 2050, prevent 4.7 million deaths per year, and improve global crop yields by 135 million metric tons per season.
“We’ve shown that implementing specific practical emissions reductions chosen to maximize climate benefits would also have important ‘win-win’ benefits for human health and agriculture,” said Shindell, when he released his findings.
This is not the first time that countries have attempted to reduce these pollutants. The U.S, Canada and Mexico agreed to reduce ozone-causing HFCs under the 2006 Montreal Protocol; however, those efforts were blocked by developing countries like China, Brazil and India.
Unlike long-lasting carbon dioxide, potent short-lived pollutants like HFCs are measured on a “real time” scale. Under an emissions reduction plan for HFCs based on historical output, developing countries would bear far more responsibility than they would under an equivalent system for carbon dioxide.
However, speaking at a meeting yesterday on the progress of international climate negotiations, Sweden’s Environmental Minister, Lena Ek, said she believed it was possible to bring China and India on board by pushing the myriad health and agricultural benefits from reducing short-lived pollutants.
“The chances of getting India and China on board are pretty good actually,” said Ek. “You are talking about saving millions of lives and improving agricultural yields by 20%. When we discussed this with India, they saw this as low hanging fruit to solve many problems at one time. They certainly seemed interested.”
Getting India and China on board to this recent agreement would be another major development in international climate negotiations. At the Durban climate talks last December, India and China finally came around in the final hour and agreed to begin new talks on an international framework with “legal force” after 2015.
But in the meantime, there’s a major gap in pledged emissions reductions that needs to be filled between 2015 and 2020. The United Nations Environment Program reports that, even if countries meet their 2020 voluntary targets agreed to in Copenhagen, the global community will still be 6 and 11 gigatons of carbon dioxide short of keeping temperature rise at 2° Celsius.
This renewed effort to reduce short-lived pollutants — emissions that contribute to more than 30% of global warming — may help partially bridge that gap.
Some environmental groups criticize the focus on short-lived pollutants, saying it provides a false sense of security and allows countries more time to build out carbon-intensive infrastructure. But if implemented alongside aggressive targets for reduce carbon dioxide emissions, this initiative could play a major part in preventing catastrophic warming.
“This is not a replacement at all for reducing carbon emissions,” said Andrew Light, a senior fellow and expert on international climate policy at the Center for American Progress. “But it delays peaking and pushes the gap a few years out. This is only effective as part of a broader carbon reduction strategy.”
Watch the video below learn more about how climate forcers work: