Reduce global soot

Given the political gridlock that threatens world efforts to counter global warming, the international community needs a common, affordable goal that has immediately observable climate and health benefits, and that can serve as a first step toward the more difficult and costly long-range objective of controlling carbon dioxide emissions.

One major air pollutant offers such a target: soot, or "particulate matter" suspended in the air. Soot is implicated by NASA in the melting of Arctic ice and Himalayan glaciers. It contributes to an estimated 1.5 million deaths a year. It has recently been estimated to be the second most important contributor to global warming next to carbon dioxide. Unlike carbon dioxide, it can be quickly removed from the atmosphere using currently available technology. Soot emissions in Northern Europe and the United States, for example, have decreased 300 percent in the past 30 years, according to a study released in March by the Scripps Institution of Oceanography, the University of California, San Diego, and the University of Iowa.

National governments are having a hard time coming to grips with global warming because the fossil fuels that drive economic development are the main human source of carbon dioxide, and the technology does not yet exist for cheaply removing this gas from the atmosphere. But recently, leaders of the world's richest countries agreed at the G-8 meeting in Japan to support a 50 percent reduction in worldwide greenhouse gas emissions by 2050.

The path to that goal remains unclear. On that same day, the BBC tested the air in Beijing, China, and found that it fails to meet World Health Organization standards for healthy air. China and India, along with other Asia nations, contribute 25 to 35 percent of the world's atmospheric soot.

Cleaning up that "Asian brown cloud," along with other worldwide sources of soot, would have clear, near-term economic, health and climate benefits. The international community should address itself to fighting soot as an important first stage in its efforts to lower greenhouse-gas emissions.