For any emission trading system (ETS) with quantity-based endogenous supply of allowances, there exists a negative demand shock, e.g. induced by abatement policy, that increases aggregate supply and thus cumulative emissions. We prove this green paradox for a general model and then apply it to...

The UK has pledged to cut greenhouse gases 68 percent below 1990 levels by 2030, to be emissions neutral by 2050, and to phase out internal combustion engine vehicles by 2030. Much progress has been made, but fully achieving these ambitious objectives with the current policy framework will be...

We investigate how irreversibility in "dirty" and "clean" capital stocks affects optimal climate policy, from both theoretical and numerical perspectives. An increasing carbon tax will reduce investments in assets that pollute, and so reduce emissions in the short term: our "irreversibility...

This paper introduces geoengineering into an optimal control model of climate change economics. Together with mitigation and adaptation, carbon and solar geoengineering span the universe of possible climate policies. Their wildly different characteristics have important implications for climate...

We develop a 2-period emission trading model for a stock pollutant with demand shocks resolving over time. We find precise conditions for efficiency of a stabilization mechanism where cumulative available permits decrease with excess supply in early periods. Our model describes the stabilization...

We develop a dynamic regulation game for a stock externality under asymmetric information and future market uncertainty. Within this framework, regulation is characterized as the implementation of a welfare-maximization program conditional on informational constraints. We identify the most...

A sufficiently rapidly rising carbon tax may increase near-term emissions compared with the case of no carbon tax. Even so, such a carbon tax path may reduce total costs related to climate change, since the tax may reduce total carbon extraction. A government cannot commit to a specific carbon...

France has a very ambitious environmental-policy agenda, aimed chiefly at cutting greenhouse gas (GHG) emissions but also at dealing with local air and water pollution, waste management and the conservation of biodiversity. The laws that followed the Grenelle de l'environnement encompass policy...