| 英文摘要: | Cutting levels of soot and other short-lived pollutants delivers tangible benefits and helps governments to build confidence that collective action on climate change is feasible. After the Paris climate meeting this December, actually reducing these pollutants will be essential to the credibility of the diplomatic process. Over the past two decades there has been an increasing amount of scientific research showing that a reduction in black carbon (BC, also known as soot), tropospheric ozone, methane and hydrofluorocarbons (HFCs) can slow near-term climate change significantly more than previously thought1. All of these compounds are short-lived climate pollutants (SLCPs) that persist in the atmosphere for days to a decade and a half — as opposed to CO2 and other long-lived gases with atmospheric lifetimes of hundreds to thousands of years, which have historically dominated scientific and political attention on climate change. The fresh scientific insights about SLCPs are opening up a new political front in the battle to mitigate climate change. With available technologies, it is possible to cut these pollutants drastically; reductions of 30% for methane, 75% for black carbon, and nearly 100% for the most potent HFCs are achievable. This would avoid up to 0.6 °C of warming by mid-century, while also slowing the rise in sea levels (Fig. 1), the melting of glaciers, and the retreat of the Arctic ice cap1. These are not hypothetical cuts; in just two decades, California, for example, has cut its emissions of black carbon and several pollutants that produce ozone by half7.
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