Climate change, uncertainty, and global catastrophic risk

The status of climate change as a global catastrophic risk is a significant point of contention. Some research characterizes climate change as a grave threat to human civilization; other research characterizes it as having relatively mild severity. This article provides a perspective on how to evaluate the considerable uncertainty about the potential for climate change to cause global catastrophe. The article shows that some prior literature has understated the basis for regarding climate change as a global catastrophic risk. In particular, the high uncertainty about climate change makes it more likely to be a global catastrophic risk and more likely to be a large global catastrophic risk. Additionally, a comparison to nuclear winter shows that much of the uncertainty about climate change as a global catastrophic risk comes from complex systems interaction in more moderate climate change scenarios. The article finds that, based on the body of evidence currently available, climate change should indeed be considered to be a global catastrophic risk. Implications for the general study of global catastrophic risk are also presented.