In addition to tail macroeconomic events (e.g. wars, financial crises and pandemics), climate change poses a threat to financial stability — with extreme climatic events increasing in frequency and intensity and policy risks putting pressure on asset valuations. We study the effect of a changing climate on asset prices and interest rates through the lens of a dynamic CAPM with rare disasters, time-varying risk and recursive preferences. In our model, a changing climate makes tail events more frequent and less predictable, increasing the premium of climate risk; interestingly, this change may not be fully reflected in the overall market risk premium that includes both components of risk: macroeconomic and environmental. Our results also support the hypothesis of a declining real rate of interest as the planet warms, while the increasing risk of climate policy reduces the participation of brown assets in the market portfolio.

We develop a conceptual framework for valuing biodiversity from an economic perspective. We argue for a dynamic economic welfare measure of biodiversity that complements the literature on benefit-cost approaches and genetic distance/phylogenic tree approaches. Using a unified model of optimal economic management of an ecosystem under ecological and genetic constraints, we identify gains from management policies leading to a more diverse system, using the Bellman state valuation function of the problem. We show that a more diverse system could attain a higher value although the genetic distance of the species in the more diverse system could be almost zero.