OP-ED CONTRIBUTORS
To Fight Climate Change, Clear the Air
By VEERABHADRAN RAMANATHAN and DAVID G. VICTOR
Published: November 27, 2010
AS the curtain rises tomorrow in Cancún, Mexico, on the next round of international talks on climate change, expectations are low that the delegates will agree on a new treaty to reduce emissions that contribute to global warming. They were unable to do so last year in Copenhagen, and since then the negotiating positions of the biggest countries have grown even further apart.
Mikel Jaso
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Yet it is still possible to make significant progress. To give these talks their best chance for success, the delegates in Cancún should move beyond their focus on long-term efforts to stop warming and take a few immediate, practical actions that could have a tangible effect on the climate in the coming decades.
The opportunity to make progress arises from the fact that global warming is caused by two separate types of pollution. One is the long-term buildup of carbon dioxide, which can remain in the atmosphere for centuries. Diplomacy has understandably focused on this problem because, without deep cuts in carbon dioxide emissions, there can be no permanent solution to warming.
The carbon dioxide problem is hard to fix, however, because it comes mainly from the burning of fossil fuels, which is so essential to modern life and commerce. It will take decades and trillions of dollars to convert all the world’s fossil-fuel-based energy systems to cleaner systems like nuclear, solar and wind power. In the meantime, a fast-action plan is needed.
But carbon dioxide is not the only kind of pollution that contributes to global warming. Other potent warming agents include three short-lived gases — methane, some hydrofluorocarbons and lower atmospheric ozone — and dark soot particles. The warming effect of these pollutants, which stay in the atmosphere for several days to about a decade, is already about 80 percent of the amount that carbon dioxide causes. The world could easily and quickly reduce these pollutants; the technology and regulatory systems needed to do so are already in place.
Take methane, for example, which is 25 times more powerful than carbon dioxide in causing warming. It is emitted by coal mines, landfills, rice paddies and livestock. And because it is the main ingredient in natural gas, it leaks from many older natural-gas pipelines. With relatively minor changes — for example, replacing old gas pipelines, better managing the water used in rice cultivation (so that less of the rice rots) and collecting the methane emitted by landfills — it would be possible to lower methane emissions by 40 percent. Since saved methane is a valuable fuel, some of this effort could pay for itself.
Unfortunately, the accounting systems used in climate diplomacy are cumbersome and offer relatively few incentives for countries to make much effort to control methane.
Big cuts are also possible in hydrofluorocarbons, or HFCs, many of which are used as refrigerants in air-conditioners and other cooling systems. The most troubling of the short-lived HFCs were invented to replace chlorofluorocarbons, refrigerants that were thinning the ozone layer in the upper atmosphere, and were also a major warming agent. Chlorofluorocarbons were regulated under the Montreal Protocol starting in 1987.
The warming effect of these HFCs is at least 1,000 times that of carbon dioxide. Unless they are regulated as chlorofluorocarbons have been, their warming effect will increase substantially in the coming decades.
Shifting from HFCs to substitutes that are 100 times less potent as climate warmers could offset nearly a decade’s increase in warming that is expected from rising emissions of carbon dioxide. The delegates in Cancún would need only to ask that the Montreal Protocol take on the further authority to regulate HFCs.
From a political point of view, the most appealing greenhouse emissions to reduce are ozone and soot, because they contribute so much to local air pollution. After all, people everywhere care about the quality of the air they breathe and see — even if most of them are not yet very worried about global warming. A desire to clean up the air is a rare point of commonality between developing and industrialized nations.
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