Environment & Climate Change

The authors break down the reasons for the United States to stay in the Paris Climate Agreement, arguing that the benefits far outweigh any potential costs. The Agreement gives the United States a seat at the table, and the ability to influence international policy on climate change, showing that the United States is open and willing to cooperate.

The author explores the role of the Montreal Protocol's assessment panel and draws lessons for the UNFCCC.

The authors explore, in particular, the implications for CO2 removal and solar geoengineering of the Paris Agreement's long-term temperature goals, provision for "removals by sinks," and market-based mitigation mechanisms.

Improvements in eco-efficiency—defined as a combination of reducing waste and reducing the use of raw inputs—offer one strategy for reducing greenhouse gas emissions while also lowering production costs. In addition, changes in culture—at the level of individual businesses, countries, or both—can enhance the eco-competitive position of these businesses and countries. This paper describes three examples from Costa Rica and shows how the goal of achieving carbon neutrality can provide incentives for improving eco-efficiency and eco-competitiveness.

The emerging pledge and review approach to international climate policy provides countries with substantial discretion in how they craft their intended emission mitigation contributions. The resulting heterogeneity in mitigation pledges places significant demands for a well-functioning transparency and review mechanism. In particular, the specific forms of intended contributions necessitate economic analysis in order to estimate the aggregate effects of these contributions as well as to permit "apples-to-apples" comparisons of mitigation efforts. This paper discusses the tools that can inform such analyses as well as the institutional needs of climate transparency.

Plants draw carbon dioxide from the atmosphere as they grow, sequestering the carbon in biomass and thus helping to mitigate climate change. This mitigation has an economic value commensurate with reduced damages from climate change. However, the U.S. National Park Service (NPS) has not calculated the carbon-sequestration benefits provided by the 84 million acres of land it manages, even though 85% of this land is vegetated.

The NPS has a dual mission—to foster both tourism ("visitation" to those researching this topic) and land stewardship. Measuring the value of carbon sequestration would complement ongoing attempts to measure the economic value of tourism by providing an initial estimate of the economic importance of one component of the NPS's stewardship obligations.

In the absence of an effective global agreement to reduce carbon emissions, some industrialized countries have taken unilateral action to reduce emissions. However, unilateral carbon policy can lead to leakage of carbon emissions and precludes abating emissions where such abatement would be least expensive (possibly in other countries). Border carbon adjustment (BCA) is one policy option to mitigate these two disadvantages of unilateral action, but the effectiveness of these measures remains unclear. Comparing the results of simulated carbon policy and BCA in multiple computable general equilibrium (CGE) models of the global economy offers several estimates of the effectiveness of BCA.

Recent research in economics shows how not to design climate treaties—and suggests how to get it right.

Emitting carbon dioxide (CO2 )—and other greenhouse gases—imposes a cost on society because it contributes to damages from climate change. This "social cost" is also known as an "externality," in that the emitter does not bear this cost. The "Social Cost of Carbon" (SCC), then, is the "marginal monetized externality value" of damages from CO2 emissions, where "marginal" refers to the next incremental unit of emissions. As damages from climate change become more evident, it becomes increasingly useful in formulating public policy (especially in connection with attendant benefit-cost analysis of that policy) to employ an SCC—that is, a numerical, non-zero value for climate damages. This paper examines the process in the U.S. government of specifying an SCC.

This April, the United States assumed the Chairmanship of the Arctic Council. The Belfer Center Environment and Natural Resources Program is releasing a series of policy briefs on the issues relating to the Arctic. This brief, focusing on security issues, is the first in this series.