Climate

The United States recently passed major federal laws supporting the energy transition, and analyses suggest that their successful implementation could reduce US emissions more than 40% below 2005 levels by 2030. However, achieving maximal emissions reductions would require frictionless supply and demand responses to the laws’ incentives and implementation that avoids polarization and efforts to repeal or undercut them. In this Perspective, we discuss some of these supply, demand and polarization challenges.

‘Moral hazard’ links geoengineering to mitigation via the fear that either solar geoengineering (solar radiation management, SRM) or carbon dioxide removal (CDR) might crowd out the desire to cut emissions. Fear of this crowding-out effect ranks among the most frequently cited risks of (solar) geoengineering. We here test moral hazard versus its inverse in a large-scale, revealed-preference experiment (n~340,000) on Facebook and find little to no support for either outcome. For the most part, talking about SRM or CDR does not motivate our study population to support a large U.S.

Given that this year’s United Nations Climate Change Conference was hosted by a petrostate and led by a fossil-fuel CEO, climate campaigners understandably had low expectations. Yet the summit did deliver some new commitments, and there is good reason to think that they are more than just empty words.

How much will it cost to meaningfully reduce greenhouse gas (GHG) emissions on a global scale? The answer is critical for assessments of how to address climate change—affecting public support, political will, and policy choices. We find that the “bottom-up” estimation approach emphasized by the United Nations Intergovernmental Panel on Climate Change (IPCC) reports considerably lower costs for emission reductions than leading “top-down” economic models.

It is both technically possible and economically feasible to eliminate almost all the carbon dioxide from iron and steel production by mid-century, thus cleaning up an industry that accounts for 10% of global emissions. But progress will not happen without a concerted policy push.

With China’s economic growth slowing at the same time that its emissions continue to rise, it is clear that its carbon-intensive investment model has run its course. Chinese leaders urgently need to follow advanced economies in shifting toward greater domestic consumption and reduced energy demand.

Carbon pricing: Across (and sometimes even within) academic disciplines, no topic under the broad umbrella of climate economics tolerates quite so large a gap between facts and dogma, and between the power of a seemingly simple idea on the one hand and raw political power on the other.

Heated academic debates between proponents and opponents of traditional economic growth under capitalism might make for good television, but they offer little in the way of solutions. Climate change demands that we achieve both growth and degrowth, depending on the activity and economic sector in question.

As long as coal plants are still operating, it is a good idea to require them capture their carbon dioxide emissions. But those designing policies to hasten such practices must tread carefully, lest they unwittingly extend the life of dirtier energy sources.