Department of Economics
University of Arizona
McClelland Hall 401EE
Tucson, AZ 85721
NBER Program Affiliations:
NBER Affiliation: Faculty Research Fellow
Information about this author at RePEc
NBER Working Papers and Publications
|June 2017||Expect Above Average Temperatures: Identifying the Economic Impacts of Climate Change|
A rapidly growing empirical literature seeks to estimate the costs of future climate change from time series variation in weather. I formally analyze the consequences of a change in climate for economic outcomes. I show that those consequences are driven by changes in the distribution of realized weather and by expectations channels that capture how anticipated changes in the distribution of weather affect current and past investments. Studies that rely on time series variation in weather omit the expectations channels. Quantifying the expectations channels requires estimating how forecasts affect outcome variables and simulating how climate change would alter forecasts.
|May 2017||Innovation-Led Transitions in Energy Supply|
I generalize a benchmark model of directed technical change in order to reconcile it with the historical experience of energy transitions. I show that the economy becomes increasingly locked-in to the dominant sector when machines and energy resources are substitutes, but a transition away from the dominant sector is possible when machines and energy resources are complements. Consistent with history, a transition in research activity leads any transition in resource supply. A calibrated numerical implementation shows that innovation is critical for climate change policy. A policymaker uses a U-shaped emission tax trajectory so as to immediately transition innovation away from the fossil sector, wait for clean technology to improve, and then hasten a transition in resource supply later in ...
|July 2012||Tipping Points and Ambiguity in the Economics of Climate Change|
with Christian P. Traeger: w18230
We model welfare-maximizing policy in an infinite-horizon setting when the probability of a tipping point, the welfare change due to a tipping point, and knowledge about a tipping point's trigger all depend on the policy path. Analytic results demonstrate how optimal policy depends on the ability to affect both the probability of a tipping point and also welfare in a post-threshold world. Simulations with a numerical climate-economy model show that possible tipping points in the climate system increase the optimal near-term carbon tax by up to 45% in base case specifications. The resulting policy paths lower peak warming by up to 0.5°C compared to a model without possible tipping points. Different types of tipping points have qualitatively different effects on policy, demonstrating the imp...