清洁空气污染可能削弱关键海洋环流

GLOBAL warming already threatens to destabilise the Atlantic Meridional Overturning Circulation (AMOC), an ocean current that is critical for Europe’s climate, and new research shows that regional clean-air policies could reduce its strength further. The smog and soot dirtying the air around the world claim some 7 million lives every year and induce illnesses that affect many others. Yet aerosols – small particles of substances like sulphur dioxide that make up most ground-level pollution – tend to reflect sunlight and brighten clouds, which wards away some of the sun’s heat. However, unlike greenhouse gases, which endure in the atmosphere for decades or centuries and end up evenly mixed throughout the atmosphere, most aerosols last less than a week. …