Quantifying the Economic Costs of Global Warming

Climate change poses a threat to the well-being of people across the globe. Rising global temperatures will increase the frequency and magnitude of extreme climate events, threatening the lives and livelihoods of vulnerable people. Yet the magnitude and persistence of these economic impacts are poorly understood, making it difficult both to design equitable mitigation and adaptation strategies and to hold emitters accountable for the impacts of their emissions. In this thesis, I combine methods from detection and attribution, climate projection, and causal inference to understand the global economic consequences of past and future climate change. I show that two extreme climate events that have not been previously integrated into climate-economy analyses---heat waves and El Niño events---reduce economic growth globally. But these impacts are highly unequal across the globe: Heat waves have their greatest effects in warm regions, and El Niño events primarily harm highly teleconnected countries. As a result, these effects fall most severely on the people that have contributed least to warming, a sign of the inequities embedded in the causes and consequences of global warming. To quantitively understand these inequities and support efforts to hold major emitters accountable for the impacts of their emissions, I develop an end-to-end attribution framework that links individual emitters to the economic effects of the warming induced by their emissions. I show that warming from the emissions of high-income countries in the global North have driven billions of dollars of economic losses in low-income, low-emitting countries. I then combine this framework with my previous results on extreme heat, showing that the emissions of major fossil fuel firms have intensified heat waves, and the resulting economic penalties, across the global tropics. These first-of-their-kind results lend scientific support to emerging discussions over climate liability and loss and damage payments. More broadly, these findings together highlight the already-emerging economic threat of global warming, raising the importance of climate mitigation and adaptation in order to avoid accelerating losses to the most vulnerable people around the globe