This paper analyzes the optimal level of public debt when taxes are used not only for funding public expenditures but also for correcting externalities from climate change. Taking into account externalities implies that the optimal policy deviates from tax smoothing. Provided cumulative marginal...

We analyze a repeated game in which countries are polluting as well as investing in technologies. While folk theorems point out that the first best can be sustained as a subgame-perfect equilibrium when the players are sufficiently patient, we derive the second best equilibrium when they are...

"Prices versus quantities" (Weitzman 1974), a hugely influential paper, is widely cited (and taught) in current debates about the best policy to reduce greenhouse gas emissions. The paper's criterion for ranking policies suggests that technological uncertainty favors taxes over cap and trade....

Limiting global warming to no more than 2°C requires global large-scale deployment of low-carbon and negative emissions technologies. This requires the development of new eco-innovations and the diffusion of new and existing ones. Existing portfolios of environmental and technology policy...

We characterize the optimal policy and policy instruments for self-enforcing treaties when countries invest in green technology before they pollute. If the discount factor is too small to support the first best, then both emissions and investments will be larger than in the first best, when...

Climate policy needs to set incentives for actors who face imperfect, distorted markets and large uncertainties about the costs and benefits of abatement. Investors price uncertain assets according to their expected return and risk (carbon beta). We study carbon pricing and financial incentives...

Policymakers and researchers worry that the low-carbon transition may be inadvertently delayed by higher global interest rates. To examine whether green investment is especially sensitive to interest rate increases, we consider the effect of unanticipated monetary policy changes on the equity...

We identify corporate commitments for reductions of greenhouse gas emissions—green pledges—from news articles using a large language model. About 8% of U.S. firms have made green pledges, and these companies tend to be larger and browner than those without pledges. Announcements of green...

We survey 861 finance academics, professionals, and public sector regulators and policy economists about climate finance topics. They identify regulatory risk as the top climate risk to businesses and investors over the next five years, but they view physical risks as the top risk over the next...

We investigate financial experts’ beliefs about climate risk pricing and analyze how those beliefs influence stock return expectations. In a comprehensive survey, we elicit experts’ beliefs using both structured and open-ended questions. We establish that most experts share the view that...