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THE CASE FOR URGENT ACTION ON SHORT-LIVED CLIMATE POLLUTANTSAlthough meeting the 2C temperature target is a worthy goal, societal wellbeing is affected by a much broader set of environmental impacts than simply global mean temperature.The massive volcanic eruption of Mt. Tambora in 1815 threw so much material into the atmosphere that it was pitch black at midday for hundreds of miles around. The incredible force of the blast thrust hot gases into the stratosphere. As those gases condensed into tiny particles and spread around the world, global temperatures dropped slightly because the particles reflected sunlight. For human societies of the time, the more important effect was the particles’ outsized impact during summer when there is more sunlight to reflect. The feeble summer sunshine slowed photosynthesis and shrunk the growing season, leading to widespread crop failures and famines in North America, Europe and Asia. This reminds us that although it is essential to greatly reduce carbon dioxide emissions as quickly as possible to limit long-term climate change, society is affected by other aspects of climate change as well. This is because of the long residence time of carbon dioxide in the atmosphere and the long lifetime of capital-intensive electricity generation capacity with high carbon dioxide emissions.There are other emissions we can target that will reduce the impacts of near-term climate change, however, the Short-Lived Climate Pollutants (SLCPs). An SLCP strategy consists of reducing emissions of methane and the multiple products of incomplete combustion, and reversing the rapid growth in emissions of industrial hydrofluorocarbons (HFCs). Success in these three areas could cut the projected global mean warming through mid-century in half.DR DREW SHINDELL, CHAIR, THE SCIENTIFIC ADVISORY PANEL TO THE CLIMATE AND CLEAN AIR COALITION (CCAC)PROFESSOR OF CLIMATE SCIENCES, DUKE UNIVERSITY110 GLOBAL VOICES