Confronting the Threat of Nuclear Winter

Large-scale nuclear war sends large quantities of smoke into the stratosphere, causing severe global environmental effects including surface temperature declines and increased ultraviolet radiation. The temperature decline and the full set of environmental effects are known as nuclear winter. This paper surveys the range of actions that can confront the threat of nuclear winter, both now and in the future. Nuclear winter can be confronted by reducing the probability of nuclear war, reducing the environmental severity of nuclear winter, increasing humanity’s resilience to nuclear winter, and through indirect interventions that enhance these other interventions. While some people may be able to help more than others, many people—perhaps everyone across the world—can make a difference. Likewise, the different opportunities available to different people suggests personalized evaluations of nuclear winter, and of catastrophic threats more generally, instead of a one-size-fits-all approach.