The world has pledged to protect 30 percent of its land and waters by 2030 to halt the rapid deterioration of critical ecosystems. We summarize the state of knowledge about the impacts of protected area policies, with a focus on deforestation and vegetation cover. We discuss critical issues...

A politically realistic approach to environmental policy seems to require avoiding significant profit-losses in major pollution-related industries. The government can avoid such losses by freely allocating some emissions permits or by exempting some inframarginal emissions from a pollution tax....

The U.S. Clean Air Act, passed in 1970 with strong bipartisan support, was the first environmental law to give the Federal government a serious regulatory role, established the architecture of the U.S. air pollution control system, and became a model for subsequent environmental laws in the...

We provide a spatial theory of clean growth to assess the global impact of the rise of renewable energy. We model the details of the combined production and transmission network of electricity ("the grid") that determine the supply and losses of energy in space. The local rate of clean energy...

In collaboration with a state environmental regulator in India, we conducted a field experiment to raise the frequency of environmental inspections to the prescribed minimum for a random set of industrial plants. The treatment was successful when judged by process measures, as treatment plants,...

In our analytical general equilibrium model where two polluting inputs can be substitutes or complements in production, we study the effects of a tax on one pollutant in two cases: one where both pollutants face taxes and the second where the other pollutant is subject to a permit policy. In...

We propose a dynamic spatial theory to analyze the geographic impact of climate change. Agricultural and manufacturing firms locate on a hemisphere. Trade across locations is costly, firms innovate, and technology diffuses over space. Energy used in production leads to emissions that contribute...