*Flooding caused by Super Storm Sandy in Marblehead, Mass., on Oct. 29, 2012*

From economicprincipals.com

SOMERVILLE, Mass.

Weighed down by not knowing what to expect of the coronavirus timetable, I spent a day last week reading about climate change. Specifically, I read Three Prongs for Prudent Climate Policy, by Joseph Aldy and Richard Zeckhauser, both of Harvard University’s Kennedy School of Government.

Paradoxically I came away feeling better. Grim though the situation they describe is, theirs is anything but a counsel of despair.

For three decades, advocates for climate change policy have simultaneously emphasized the urgency of reducing greenhouse gas emissions and provided unrealistic reassurances of the feasibility of doing so. It hasn’t worked out, say Alby and Zeckhauser.

The Kyoto Protocol of 1997 imposed binding commitments on industrial nations to reduce emissions below 1990 levels in a decade. They exceeded them. Even so, global carbon dioxide emission grew 57 percent over the same ten years, because developing nations hadn’t joined the accord.

So the Paris Agreement of 2015 established “pledge and review” commitments by from virtually every nation in the world, designed to prevent warming of more than 2 degrees centigrade by 2030. But even if every country honors its pledge, the policy is unlikely to succeed in meeting the target, say Aldy and Zeckhauser,

That’s because what’s already in the atmosphere is a stock, not a flow. From the pre-industrial period to 1990, carbon dioxide concentration increased by about 75 parts per million. Since 1990, CO2 has increased by another 55 parts per million, and despite the agreements, the rate of increase is apparently accelerating.

Meanwhile, global temperature have increased around half a degree centigrade in the last 30 years. They are likely to rise faster in the years ahead. Storms, droughts, floods, fires, melting will increase. Mass migrations in response to these weather events have barely begun.

So, the authors say, after 30 years of single-minded stress on emission reductions in climate change discourse, two other policy prongs are urgently needed.

One of these headings, adaptation, is well-known and uncontroversial, except that it costs a lot in more complicate applications than in simple adjustments. Moving heating plants from basements to upper stories so that equipment is not damaged by flooding is simple and relatively cheap. Sea barriers and storm gates to protect coastal cities are another. The sea wall to protect the Venice lagoon is almost finished, but the Army Corps of Engineers plan to protect New York City would take 25 years to construct.

The other strut, amelioration, is considerably less discussed, mainly for fear of the ease with which the remedy may be embraced, once the cost differences are better understood. “Solar radiation management” means putting a sunscreen into the sky – most likely sulfur particles injected into the upper atmosphere by specially built airplanes. Major volcanic eruptions over the centuries have proven that the principle will work, though myriad details of its practical application are hazy. What’s clear is that so-called “geo-engineering” would cost considerably less than emissions reduction or adaptation, especially if time were of the essence.

The only place I see radiation management brought up regularly in the things I read is in Holman Jenkins’s twice-a-week column in the editorial pages of The Wall Street Journal. The other day Jenkins noted Amazon’s Jeff Bezos’s intention to spend $10 billion to fight climate change. Don’t spend it touting nuclear power, Jenkins advised; Bill Gates is already working on that. And never mind carbon taxation; that must come, if it comes, from the Left. Instead, why not atmospheric aerosol research?

Right though Jenkins may be about the possibilities of solar-radiation mitigation, he is preaching to those ready to be converted. That’s why I was interested in the Aldy-Zeckhauser paper: they are several steps closer to the mainstream. Aldy served as the Special Assistant to the President for Energy and Environment in 2009-2010. Zeckhauser works in in the tradition of tough-minded cooperation pioneered by his mentor, the policy intellectual (and Nobel laureate) Thomas Schelling.

But if we can’t handle a virus, what hope is there of devising effective policies against climate change? That’s just the point: we can handle a virus. It just takes a year, or, probably, two. The problem of arresting global warming is much more difficult, but if you believe the science, there can be no doubt that disastrous events will sooner or later cause public opinion around the world to come around

Wisdom begins with the recognition that there are three policy prongs with which to address the problem of greenhouse gases, not just one. Slowing the effects of carbon dioxide emissions – while continuing to slow emissions themselves – turns on the next election, and the two or three elections after that.

David Warsh, an economic historian and a veteran columnist, is proprietor of economicprincipals.com, where this essay first appeared.