This paper explores global perceptions and understanding of climate change and policies, examining factors that influence support for climate action and the impact of different types of information. We conduct large-scale surveys with 40,000 respondents from 20 countries, providing new international data on attitudes toward climate change and respondents’ socioeconomic backgrounds and lifestyles. We identify three key perceptions affecting policy support: perceived effectiveness of policies in reducing emissions, their impact on low-income households, and their effect on respondents’ households (self-interest). Educational videos clarifying policy mechanisms increase support for climate policies; those merely highlighting climate change’s impacts do not.

Notwithstanding great progress in scientific and economic understanding of climate change, it has proven difficult to forge international agreements because of free-riding, as seen in the defunct Kyoto Protocol. This study examines the club as a model for international climate policy. Based on economic theory and empirical modeling, it finds that without sanctions against non-participants there are no stable coalitions other than those with minimal abatement. By contrast, a regime with small trade penalties on non-participants, a Climate Club, can induce a large stable coalition with high levels of abatement.

This paper uses international trade data to examine the effects of climate shocks on economic activity. At the aggregate level, Melissa Dell, Benjamin F. Jones, and Benjamin A. Olken (2008) (hereafter, DJO) have demonstrated that higher temperatures in a given year reduce the growth rate of GDP per capita, but only in poor countries. The analysis of trade data in this paper builds on that finding, with three principal motivations. First, international trade links the fortunes of countries, providing potentially important conduits for geographically limited climatic impacts to have global economic effects. Second, international trade data is the best available source for identifying economic activity worldwide separately by narrowly defined sectors. Examining international trade data, one can thus say more precisely what sectors are affected by climatic changes. Finally, the trade data, collected by the importing country, provides a check on the potentially low-quality national accounts data provided by the home country.

This paper takes as given that (i) the burning of fossil fuel increases the carbon dioxide content in the atmosphere, which (ii) in turn leads to global heating and global climate change of a

There is a growing consensus that emissions of greenhouse gases due to human activity will alter the earth’s climate, most notably by causing temperatures, precipitation levels, and weather variability to increase. The design of optimal climate change mitigation policies requires estimates of the health and other benefits of reductions in greenhouse gases; current evidence on the magnitude of the direct and indirect impacts, however, is considered insufficient for reliable conclusions (A. J. McMichael et al. 2003).

An effective climate change treaty must promote the joint supply of two global public goods: climate change mitigation and knowledge of new technologies that can lower mitigation costs. R&D is especially needed to bring about substantial, long-term reductions in atmospheric concentrations of greenhouse gases, for this will require the development and diffusion of revolutionary, “breakthrough ” technologies (Martin I. Hoffert et al. 2002). In principle, such an outcome could be realized by the Kyoto Protocol approach, if that agreement were strengthened over time. However, that response may be inadequate (Kyoto makes no provision for R&D)—and, as I shall demonstrate, unlikely to succeed in any event. Can a treaty system relying directly on targeted R&D and the adoption of breakthrough technologies perform better in this same setting of anarchic international relations? I shall show that, as a general rule, the answer is no. Essentially, the same forces that undermine Kyoto also challenge the R&D and technology approach. There is one exception to this rule: R&D leading to breakthrough technologies exhibiting increasing returns can improve dramatically on the Kyoto approach, even when these technologies are otherwise inferior to the alternatives available. This suggests that our approach to treaty design should be strategic. 2I. The Kyoto Approach Begin by considering the abatement decisions of countries in the absence of a multilateral agreement. Let qi denote country i’s abatement and let Q denote aggregate abatement; with N countries, Q = qi i=1 N Â. Finally, let country i’s payoff be given by p i = bQ- c qi

William D. Nordhaus delivered his Prize Lecture on 8 December 2018 at the Aula Magna, Stockholm University.

Manmade climate change (CC) has catastrophic consequences. The United States has already experienced wholesale population realignment due to climate as households have relocated to the Sunbelt and West. The irony is that people are moving toward the heat and major storms associated with CC. As CC intensifies, with high rates of internal US factor mobility, firms and households will likely again relocate to areas with higher utility and profits, reducing CC costs. Yet current research typically focuses on CC costs in a given location without considering this realignment. We propose several avenues to overcome such shortcomings in US CC modeling.