• Wisdom of the Experts: Using Survey Responses to Address Positive and Normative Uncertainties in Climate-Economic Models

    The social cost of carbon (SCC) and the climate-economic models underlying this prominent US climate policy instrument are heavily affected by modeler opinion and therefore may not reflect the views of most climate economists. To test whether differences exist, we recalibrate key uncertain model parameters using formal expert elicitation: a multi-question online survey of individuals who have published scholarship on the economics of climate change.

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  • Option Value and the Social Cost of Carbon: What Are We Waiting For?

    Scientists and economists have long recognized that significant uncertainties and irreversibility characterize climate change. And yet, the social cost of carbon (SCC), the preeminent policy tool to address climate change applied by the U.S. government, does not include the option value (OV) that arises due to these characteristics. We demonstrate a simple methodology for approximating the OV underlying the SCC using the Bachelier formula.

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  • Federal Lands and Fossil Fuels: Maximizing Social Welfare in Federal Energy Leasing

    This Article suggests a rational path forward for federal fossil fuel leasing. Just as a private company would seek to maximize net revenue in its operations, Interior should seek to manage its program to provide maximum net benefits to the public, to whom public resources belong. This includes accounting for all of the costs and benefits of leasing—including environmental and social costs—and adjusting the fiscal terms of its fossil fuel leases to recoup unmitigated externality costs. The Article describes how maximizing social welfare is consistent Interior’s statutory mandates, legislative history, judicial precedent, and principles of executive review that instruct agencies to maximize the net benefits of their policy choices. The reforms suggested here can significantly increase revenue for states and the federal government while reducing greenhouse gas emissions, illustrating the utility of using fiscal reform as a policy lever in the absence of comprehensive climate change legislation.

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  • Mineral Royalties: Historical Uses and Justifications

    Governments and private landowners have collected royalties on mineral resources for centuries. When comprehensive measures to account for the environmental externalities of mineral extraction are politically or practically unavailable, federal and state governments may consider adjusting royalty rates as an expedient way to account for these externalities and benefit society. One key policy question that has not received attention, however, is whether a royalty rate can and should be manipulated in this way, assuming statutory discretion to do so.

    This article fills that gap by evaluating the argument for increasing federal or state fossil fuel royalty rates through historical, theoretical, and practical lenses. To that end, this article in turn considers the meaning of royalties, the economic justifications for royalties, the legislative history of the implementation of federal royalties, and the considerations that private landowners have relied upon in setting royalties. This article concludes that it would be appropriate for governments to adjust mineral royalty rates to account for negative externalities not otherwise addressed by regulation or to otherwise promote public welfare. Such use of royalties is consistent with the historical record. Royalties have been used as pragmatic policy tools from almost their inception, and federal and state governments have often exercised their existing statutory discretion to adjust mineral royalty rates to promote public welfare.

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  • Best Cost Estimate of Greenhouse Gases

    Despite the Trump administration’s decision to withdraw the official estimate of the Social Cost of Carbon and disband the interagency working group that developed it, a group of prominent economists and lawyers, including several Policy Integrity staff members, have highlighted the metric’s continued validity for policymaking in recent letter published in the journal Science.

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  • Few and Not So Far Between: A Meta-analysis of Climate Damage Estimates

    Given the vast uncertainty surrounding climate impacts, meta-analyses of global climate damage estimates are a key tool for determining the relationship between temperature and climate damages. Due to limited data availability, previous meta-analyses of global climate damages potentially suffered from multiple sources of coefficient and standard error bias. To address and test for these biases, we expand on previous datasets to obtain sufficient degrees of freedom to make the necessary model adjustments, including dropping duplicate estimates and including methodological variables. Estimating the relationship between temperature and climate damages using weighted least squares with cluster-robust standard errors, we find strong evidence that duplicate and omitted variable biases flatten the relationship. However, the magnitude of the bias greatly depends on the treatment of speculative high-temperature (>4 ◦C) damage estimates. Replacing the DICE-2013R damage function with our preferred estimate of the temperature–damage relationship, we find a three- to four-fold increase in the 2015 SCC relative to DICE, depending on the treatment of productivity. When catastrophic impacts are also factored in, the SCC increases by four- to five-fold.

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  • The Social Cost of Carbon: A Global Imperative

    To solve the unprecedented global commons problem posed by climate change, all nations must internalize the global externalities of their emissions. If not, collective efforts will never achieve an efficient, stable climate outcome. The United States’ practice of looking at the global impact of emissions has come under attack in courtrooms and academic journals, with some arguing that the U.S. should instead consider only the domestic impacts of climate change in its decisionmaking.

    In a letter published in Review of Environmental Economics and Policy, we argue that federal agencies should continue to use a global number for Social Cost of Carbon, as developed by the Interagency Working Group on Social Cost of Carbon. First, the United States benefits tremendously if other countries set policy based on global rather than local effects. From a legal perspective, not only does international law—the U.N. Framework Convention on Climate Change—commit the United States to account for global effects, but domestic laws like the Clean Air Act and the National Environmental Policy Act also either require or give discretion to agencies to consider global climate costs. Many seemingly “foreign” climate damages would actually spill over to harm the United States.

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  • Think Global: International Reciprocity as Justification for a Global Social Cost of Carbon

    U.S. climate regulations present a special case of federal agencies applying a global, rather than exclusively domestic, perspective to the costs and benefits in their regulatory impact analyses. Since 2010, federal agencies have emphasized global valuations of climate damages for policies that affect carbon dioxide emissions, using a metric called the “Social Cost of Carbon.” More recently, agencies have also begun to use a global valuation of the “Social Cost of Methane,” for methane emissions. Yet lately, these global metrics have come under attack in courtrooms and academic journals, where opponents have challenged the statutory authority and economic justification for global values. This paper defends a continued focus on the global effects of U.S. climate policy, drawing on legal, strategic, and economic arguments.

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