Don’t Anchor a Carbon Tax to the Social Cost of Carbon

Editor’s note: Yesterday the world’s most influential newspaper finally did what CTC and other carbon tax proponents have sought for years: publish a ringing endorsement of a U.S. carbon tax. With its editorial, The Case for a Carbon Tax, the New York Times joins the growing community of opinion leaders, policy experts and, yes, elected officials who not only recognize the power of carbon taxes to quickly and equitably reduce emissions but also sense the emergence of a political critical mass that can enact fees into law. This heartening development signals that it’s not too soon to focus on the design of a U.S. carbon tax, especially its magnitude and rate of increase, as CTC senior policy analyst James Handley does in this post.

Which is the more effective way to set a tax on carbon pollution?

A. Start aggressively, then raise the rate slowly (“sprint”).

B. Start modestly, then raise the rate briskly and predictably (“marathon”).

You probably guessed that if the goal is to instill incentives that will bring about big emission reductions fast enough to avoid runaway global warming, the answer is B, the marathon. Yet a leading U.S. Senate advocate of legislative action on climate seems to be starting off like a sprinter, perhaps because his legislation is pegged to estimates of the Social Cost of Carbon that don’t account for the possibility that climate change will turn out to be catastrophically costly.

More on that senator in a moment — after this tutorial:

The Social Cost of Carbon (SCC) is a construct to quantify in monetary terms the damage caused by each additional ton of CO2 added to the atmosphere. While the SCC may sound arcane or academic, estimating its magnitude has real world implications: governments are pegging climate-related regulatory decisions to SCC estimates. A low SCC can make all but the lowest-cost clean-energy policies pencil out as expensive; higher estimates justify more rapid and aggressive measures, since moving too slowly to reduce emissions shows up as a mistake whose costs accumulate at a frightening pace.

Ice Shelf on eastern edge of Edgeoya, Norway. Waterfall. (20090812) (Strcorarius parasiticus)

Ice Shelf Melting in Eastern Norway (Paul Hoogeveen, Flickr)

Calculating the damage from a ton of CO2 turns on a host of assumptions that span wide ranges. Not surprisingly, estimates of the SCC reported in the peer-reviewed economics literature range from as little as $10 per ton of CO2 to over $400. A profoundly important modeling choice is how heavily to weigh the risks of climate-induced catastrophes. High-risk climate scenarios with nearly infinite costs, such as rapid release of methane from arctic permafrost or sudden sliding of vast ice masses into the ocean, “misbehave” in the equations used for conventional cost-benefit analysis, leading some modelers to omit them altogether.

One widely-used model assumes that economic growth rates will not be affected by climate change, thereby predicting that half of the world’s economic activity would continue after a whopping 18 degrees C of global warming. Other models dilute the high-risk scenarios by assigning them arbitrarily low probabilities that suppress their impact when their costs are averaged in with low-risk scenarios. A further problem in estimating the SCC is the bias toward high “discount rates” that telescope future impacts down to seemingly manageable proportions.

Amidst fraught debate and widely-divergent estimates, the Interagency Working Group has settled on $42 per ton of CO2 as the “official” U.S. government social cost of carbon. While that’s an improvement over past practice that omitted climate costs entirely — tacitly, an SCC equal to zero — the $42 figure grossly understates the large-scale global risks that dominate concern over global warming and climate change. [Read more…]


Last modified: June 28, 2015

Book Review: “Climate Shock”

Rachael Sotos is a political theorist and adjunct professor with a background in philosophy, classics and environmental studies.

Climate Shock: The Economic Consequences of a Hotter Planet, is both a tidy summation of the state of the art in climate economics and a powerful call for action. For all the uncertainties and challenges, “the overall policy framework needed for addressing climate change is clear and has been for decades,” state co-authors Gernot Wagner and Martin L. Weitzman (p. 23). “Carbon dioxide is the problem. Pricing it properly is the solution.”(38)

climate shock coverWagner, a senior economist at the Environmental Defense Fund, and Weitzman, a celebrated economist at Harvard, are an intriguing blend of young and elder, and realist and idealist. They exhort economists and climate advocates to get past the “epic debates” between taxes and cap-and-trade and, while consensus builds toward carbon pricing, to engage in the work required for “second -, third-, and fourth-best solutions”(26): electricity grid reform, stronger CAFE standards, and strategic application of subsidies and U.S. EPA regulations. “At the very least,” they say, “these regulations could provide a real bargaining chip when it comes to U.S. Congress considering comprehensive climate policy and a direct price on carbon down the line.”(19).

Flying their Pigovian colors from Preface to Epilogue, the authors are emphatic and unambiguous; “Putting a proper price on carbon isn’t a question of if, it’s a question of when.(xi) Our best hope is “a high enough price on carbon to reflect its true cost to society.”(152)

Unfortunately, the bracing clarity of Climate Shock appears to have been lost on some reviewers. Earlier this month, NY Times columnist Joe Nocera misconstrued Wagner and Weitzman’s extensive discussion of geo-engineering as surrender to the political obstacles to carbon pricing. On Nocera’s reading, insofar as “a carbon tax on the worst emitters has gotten nowhere,” it’s time for Plan B: “chemo for the planet.” Au contraire, Wagner and Weitzman do not delve into geo-engineering scenarios like sulfates dispersal in lieu of ambitious policies to reduce emissions. Rather, they insist, “the specter of geo-engineering should be a clarion call for action. Decisive, and soon.”(29)

If Nocera reconfigured Wagner and Weitzman to suit his own techno-utopian ends, Yale Nobel economist Robert J. Shiller, also in the Times, willfully invested Climate Shock with libertarian designs. Directly contravening the thoughtful and informative discussion of social change presented in Climate Shock (and previously thematized in Wagner’s 2011 But Will the Planet Notice?), Shiller proposed idealistically-motivated incrementalism as a way around Kyoto’s failure “to impose strict taxes on carbon emissions.”

According to Shiller, Wagner and Weitzman “say that we should be asking people to save our climate by taking many small, individual actions.” Climate Shock actually says the opposite: “the numbers don’t add up. They’ll only begin to add up when environmentalists use their collective political powers to move the policy needle in the right direction, toward a price on carbon.”(40) (See also CTC director Charles Komanoff’s recent takedown of Shiller’s piece in regard to both facts and theory.)

Shiller’s misreading is doubly unfortunate because, as Wagner and Weitzman point out, the imperative to seriously engage policy must be directed toward average citizens, “those in the middle of the political spectrum,” as well as those already conversant with climate economics.(136) Certainly we should all do what we can to encourage virtuous cycles of ethical engagement and political participation – “Recycling well leads to better environmental policies, which allow for a more environmentally enlightened citizenry; a more enlightened citizenry, in turn, leads to more people recycling well.”(132)

"Climate Shock" authors Martin Weitzman (left) and Gernot Wagner.

“Climate Shock” authors Martin Weitzman (left) and Gernot Wagner.

Indeed. But, as Wagner and Weitzman are right to remind: in a greenwashed world seemingly structured to distract and misinform the average person, the most virtuous deeds can dead end. In the practical economics of everyday life, single actions sometimes crowd out other forms of engagement: “when people substitute single, individual actions – like recycling – for larger policy actions – like voting.”(133) Pigovians from start to finish, Wagner and Weitzman are emphatic: “if you have to make a choice between recycling and voting for a price on carbon, choose voting.”(137)

Yet another review, this one by Yale economist William D. Nordhaus in the current New York Review of Books, is notable on several grounds, not least of which is Nordhaus’s outsized reputation as a pioneering climate economist and modeler. Respectful in tone, Nordhaus engages of Climate Shock’s discussions of geo-engineering, the economics of uncertainty and the pitfalls of negotiating climate treaties. Strangely, however, Nordhaus takes up Weitzman’s path-breaking analyses of catastrophic risk without acknowledging any critiques of his own perennially optimistic approach.
[Read more…]


Last modified: May 29, 2015

Arctic Oil vs. Carbon Tax? It’s Not Even Close.

It is true that the stroke of the presidential pen with which Barack Obama last week granted Shell Oil Corp. permission to drill off Alaska’s Arctic Coast cannot also put into force a U.S. carbon tax, without authorization by Congress. And it is all too possible that when climate reality eventually sweeps over the Capitol, the resulting carbon tax may be modest in scale and take a lot longer than a decade to reach the $100/ton level that would drive massive reductions in fossil fuel use and CO2 emissions.

All the same, it’s instructive to compare the capacity of Arctic drilling to supply oil with that of a robust carbon tax to quench the need for it. The outcome — the carbon tax wins — may not surprise. But the lopsidedness is startling: in just its tenth year, the carbon tax proposed last November by Rep. Jim McDermott (D-WA), starting at $12.50 per metric ton of carbon dioxide and rising annually by $12.50 as well, would be eliminating the need for oil at around a dozen times the rate at which Shell would be pulling the stuff from the Arctic.

Oil savings from a robust carbon tax dwarf oil "gains" from Arctic drilling.

Oil savings from a robust carbon tax dwarf oil “gains” from Arctic drilling.

Here are the numbers:

♦ Royal Dutch Shell’s Chukchi Sea project is projected by the U.S. Bureau of Ocean Energy Management to extract 4.3 billion barrels of crude over a 44-year period. (See Chukchi Sea Oil & Gas Lease Sale 193 Draft Second Supplemental Environmental Impact Statement, Volume 1 [pdf]; go to pp. 6 or 62 or 182 of 694.) This equates to daily production of 268,000 barrels. An estimated 2.2 trillion cubic feet of methane (natural gas) would be extracted as well; on a btu basis that equates to 360 million barrels of oil, or 23,000 barrels a day. Combined extraction of hydrocarbons is then around 290,000 barrels a day. (Note that we have not netted the energy expended to “discover,” extract and transport the oil.)

♦ For the carbon tax, we modeled McDermott’s Managed Carbon Price Act of 2014, setting the annual increases as the midpoint between the bill’s floor and ceiling prices. The price per U.S. (not metric) ton of CO2 in the tenth year, 2024, is $113.40. (Our model, which we’ll update soon, had the tax starting in 2015.) As indicated in the graph, the reductions in petroleum requirements would be substantial in every consuming sector. They sum to 3,486,000 barrels a day — 12 times the 290,000 bpd equivalent anticipated from Shell’s Arctic venture.

The estimated oil savings from the McDermott carbon tax amount to nearly one-fifth of U.S. oil consumption in both 2013 (the last data year in our model) and 2024 projected without a national carbon price. The biggest reduction in absolute terms is in what we call personal ground travel (chiefly driving), which dominates petroleum use. But on a proportional basis the savings would be greater in commercial sectors such as freight movement, oil refining, and construction, as the unmistakable price signal from the annually rising tax drives innovation enabling lower usage.

Still, the projected reduction in gasoline consumption for personal ground travel in 2024, 1.4 to 1.5 million barrels per day, commands attention. [Read more…]


Last modified: May 27, 2015

Last modified: June 1, 2015

Harvard Economist Charts Escape From Kyoto

[T]he quantity-based Kyoto-type approach [to UN climate negotiations] has pretty much broken down, leaving the world with a highly non-optimal patchwork of sporadic regional volunteerism that does not address centrally how to correct the critical externality of global warming.  — Harvard economist Martin Weitzman.

Which is simpler: negotiating one price, or 190 emissions caps?

The Kyoto Protocol is broken. What can replace it? Professor Weitzman, considered one of the world’s most influential economists, proposes a game change: Instead of squabbling over the quantity of fossil fuels each nation may burn, negotiate a single carbon price all can adhere to.

Weitzman is best known for modelling the economics of catastrophic climate change. In a ground-breaking 2009 paper, he demonstrated that conventional cost-benefit analysis under-weights the risk of catastrophic scenarios. In two new papers, he scrutinizes the Kyoto Protocol’s quantity-based structure through the lens of game theory. He calls Kyoto’s attempt to set and divvy up a global emissions cap “the ultimate… top-down worldwide treaty.” That’s not a compliment. Observing that Kyoto hasn’t come close to its goal of “an internationally harmonized binding system of emissions caps,” Weitzman shows why: the Kyoto framework induces each nation to game the system by attempting to maximize the efforts required of others while minimizing its own.

Weitzman lays out three criteria for an effective global emissions reduction system:

1. It should induce cost-effective emissions reductions.

2. It should allow negotiators to focus on negotiating one central and highly salient parameter.

3. It should align negotiators’ incentives toward internalizing climate costs.

On the first criterion, Weitzman points out that while a carbon tax is more easily administered and more transparent than a cap-and-trade system, a carbon cap or a tax can both achieve cost-effective emissions reductions.

On the second, Weitzman builds on Nobel-laureate Thomas Schelling’s pioneering game theory analysis establishing the importance of a clear focal point in negotiations. Kyoto’s quantity-based approach assigning different binding emissions quotas to each nation has no focal point. In contrast, a price-based negotiation offers a single focal point for all parties.

And building on the seminal work of Ronald Coase, Weitzman stresses the importance of minimizing transactions costs. Coase showed that parties that might otherwise negotiate an agreement can be deterred by the high costs of getting to yes. Weitzman points out that any quantity-based structure such as Kyoto necessarily multiplies transaction costs: “It is easier to negotiate one price than n quantities — especially when the one price can be interpreted as ‘fair’ in terms of equality of effort,” he writes.

The bulk of Weitzman’s analysis focuses on his third and most important criterion: the need to negotiate a structure that counteracts parties’ national self-interests and aligns their incentives toward reducing emissions. [Read more…]


Last modified: May 27, 2015

A Carbon Tax Can Carry Earth Day’s Legacy

In 1970 I was teaching math in a New York City suburb. On Earth Day I stood at a highway off-ramp with members of the high school ecology club. One of their signs read, “The Earth is a Closed Garage.” Another said, “Make Polluters Pay.”

There’s been some progress since then. Breathing New York’s air, once equated to smoking two packs of cigarettes a day, is many times safer. Wind turbines now provide five percent of the nation’s power, and electricity produced with solar cells rose ten-fold in the past three years. Driving has flatlined nationwide over the past decade, partly because Americans are strapped but also because the intoxication with cars is wearing off.

That’s great news for the environment, but it’s not nearly enough for climate. CO2 levels are still rising inexorably. Ditto global temperatures, polar ice melting and extreme weather. Emissions need to be cut radically even as seven-and-a-half billion people strive for prosperity.

For that to happen, prices of fossil fuels have to reflect the climate costs of carbon pollution. The way to do this, of course, is with carbon taxes:

To demystify carbon taxes and showcase their appeal, we’re rolling out the Carbon Tax Center’s first video. It explains how a carbon tax will transform investment, re-shape consumption and sharply reduce carbon emissions. As the video shows, no other policy can match its reach or simplicity. No other policy can be replicated globally, from China to Chile to Chad.

A carbon tax is no mere “technical fix.” It’s both a symbol and a means for us to respect nature and each other.

The central messages on Earth Day 1970 were to abide by nature’s limits and make polluters pay. On this Earth Day, let’s spread the word about a carbon tax. Let’s educate and organize so that the U.S. and other nations make taxing carbon the central policy to combat catastrophic climate change and sustain the Earth we love.


Last modified: April 22, 2015

Carbon Tax Polling Milestone: 2/3 Support if Revenue-Neutral

For more years than I care to count, the Carbon Tax Center beseeched pollsters to take Americans’ temperature on revenue-neutral carbon taxes. Time and again we explained that polling about carbon taxes had to incorporate the option of returning revenues to households ― as most carbon tax bills would do. Otherwise, the tax came off as all stick and no carrot, and about as appealing to most folks as a cold shower.

Finally, a Stanford University-Resources for the Future poll asked that question. The results, released today, show that two-thirds of Americans support making corporations pay a price for carbon pollution, provided the revenues are redistributed, i.e., made revenue-neutral. The poll’s finding is the most powerful indication yet that the public is warming to carbon taxation as the premier policy for combating climate change.

Poll-Graphic-Pie-Chart-AltStanford and RFF commissioned the polling firm SSRS to interview 1,023 U.S. adults on climate-related issues in January. Two findings from the poll — that Americans of Hispanic descent are particularly climate-concerned, and that half of Republicans would favor a presidential candidate who supports fighting climate change — led to front-page New York Times stories. (Click here for the story on Hispanics and here for the story on Republicans.) The full poll was made publicly available today at a briefing at the National Press Club in Washington.

The poll was supervised by RFF university fellow Jon Krosnick, who has been polling Americans on climate change for two decades as head of Stanford’s Political Psychology Research Group. Its section on carbon taxation included these two questions: [Read more…]


Last modified: April 30, 2015

Climate Idealism Can’t Hold a Candle to Collective Action

Why do Copenhageners ride bicycles? The key reason, says Yale economist and best-selling author (“Irrational Exuberance”) Robert J. Shiller, is that Danes are idealists who resolved, after the oil crisis of the 1970s, “to make a personal commitment to ride bicycles rather than drive, out of moral principle, even if that was inconvenient for them.”

“The sight of so many others riding bikes motivated the city’s inhabitants and appears to have improved the moral atmosphere enough,” Shiller wrote in yesterday’s New York Times, that the share of working inhabitants of Copenhagen who bike has reached 50 percent.

From “Copenhagen: City of Cyclists” (2010), a report by the City of Copenhagen.

From “Copenhagen: City of Cyclists” (2010), a report by the City of Copenhagen.

In much the same way, Shiller argues, “asking people to volunteer to save our climate by taking many small, individual actions” may be a more effective way to bring down carbon emissions than trying to enact overarching national or global policies such as carbon emission caps or taxes.

Goodness. Rarely do smart people so badly mangle both the historical record and basic economics. I say “people” because Shiller attributes his column’s main points to a new book, “Climate Shock: The Economic Consequences of a Hotter Planet” by Gernot Wagner of the Environmental Defense Fund and Martin L. Weitzman, a Harvard economist. And I say “smart” because the three stand at the top of their profession. Shiller won the Economics Nobel in 2013, Weitzman is a leading light in the economics of climate change, and Wagner is highly regarded young economist.

But mangle they have (I haven’t seen the Wagner-Weitzman book but assume that Shiller represents it fairly).

Let’s start with the history, which is fairly well known to anyone versed in cycling advocacy, as I’ve been since the 1980s, when I spearheaded the revival of New York City’s bike-advocacy group Transportation Alternatives (as recounted here.) Copenhagen’s 40-year bicycle upsurge, and indeed much of the uptake of cycling across Denmark, Germany and the Netherlands, came about not through mass idealism but from deliberate public policies to help cities avoid the damages of pervasive automobile use while reducing oil dependence.

If idealism played a part at the outset it was a social idealism that instructed government to undertake integrated policies ­― stiff gas taxes and car ownership fees; generously funded public transit; elimination of free curbside parking; provision of safe and abundant bicycle routes ― that enabled Copenhageners to do what they evidently desired all along: to use bikes safely and naturally.

The telltale is in the graphic. Only one in eleven Copenhageners who cycle have environment and climate in mind. The majority do it because it’s faster than other ways to travel, and around a third of cyclists say they ride because it’s healthy, inexpensive and convenient ― belying Shiller’s meme of Danes idealistically choosing bikes despite their inconvenience vis-à-vis cars. [Read more…]


Last modified: April 15, 2015

For Bioenergy, Mandates and Subsidies Trump even Carbon Taxes

The Carbon Tax Center is often asked why a carbon tax is needed; wouldn’t removing tax subsidies be sufficient to let efficiency and renewables compete on even terms with fossil fuels?

Our stock answer is that the subsidies the tax code confers on fossil fuels (as well as on some other extractive industries) are peanuts compared to their environmental subsidies, especially free dumping of CO2 into the atmosphere. The needed market corrective is huge and can come about only via a significant tax on carbon pollution.

Ethanol refinery

Ethanol production has always been energy-intensive

But bioenergy presents a starkly different picture. As recently as a decade ago, bioenergy sources — biofuels for transportation and biomass for electricity — seemed to have gained full-fledged membership in the “renewable energy club” along with wind, solar, small hydro and geothermal energy. To boost bioenergy production, Congress endowed biofuels with subsidies that now amount to about $1 per gallon of ethanol and $2 per gallon of biodiesel.

Congress also enacted mandates that, if left in place, will compel a tripling of U.S. biofuel output by 2022. Biomass for electricity generation is also poised to gain a huge boost if the final version of EPA’s Clean Power Plan carries over a longstanding but highly questionable assumption that biomass burning is “carbon-neutral.”

Since that honeymoon, closer scrutiny of bioenergy’s lifecycle emissions has been revealing a complicated and far less promising picture. Biofuel production typically involves substantial fossil fuel inputs. Moreover, biofuel mandates and subsidies tend to push land out of other carbon-sequestering uses including food production. And closer study of biomass burning is calling into question the “carbon-neutral” assumption: that growing wood or other biomass captures the same amount of CO2 that subsequent burning for electricity generation releases.

We discuss these issues in detail — and with abundant links to the key literature — in our new “Carbon-Taxing Biofuels” page. While our views are still evolving, we think it’s clear that removing bioenergy subsidies and mandates and preventing EPA from letting electricity generators claim credit for biomass as carbon-neutral would do more to internalize the climate costs of bioenergy than even a hefty carbon tax.

It’s a thorny issue that will only grow more important. Take a look at our new page and let us know what you think.

Photo: Iowa State University Extension Service


Last modified: March 26, 2015

One Cheer for the Guardian’s Divestment Campaign

The worldwide fossil fuel divestment campaign got a huge boost this week when Guardian editor Alan Rusbridger boldly thrust his paper into the fray. Britain’s most respected newspaper is urging readers to sign a petition by demanding that the Gates Foundation and the Wellcome Charitable Trust divest from the world’s top 200 fossil fuel companies within five years.

Divestment can’t loosen the fossil fuel stranglehold without a carbon tax.

Combined, the two charities manage over $70 billion in assets. Both say they consider climate change a  serious threat. But last year the Gates Foundation invested at least $1 billion of its holdings in 35 of the top 200 carbon reserve companies, while the Wellcome Trust invested $834 million in fuel-industry mainstays Shell, BP, Schlumberger, Rio Tinto and BHP Billiton.

We’re both elated and concerned by Rusbridger’s audacious move. Elated that this distinguished and brave journalist has thrown down the gauntlet to the global fossil fuel industry. But concerned that this divestment campaign may raise false hopes.

As Matthew Yglesias articulated last year in a thoughtful piece on Slate, divestment by socially responsible investors, universities and even governments won’t starve capital flows to fossil fuel corporations anytime soon. That’s because in a global market, every share of stock we activists dutifully unload will be snatched up in milliseconds by some trader who can bank on humanity’s continued dependence on fossil fuels to continue generating profits.

South Africa’s historic divestment campaign — the one that helped topple Apartheid and enshrined divestment as a tool against oppression  — was paired with a UN-sponsored boycott of South African goods. Not just aiming at the supply of capital but destroying the demand for goods sheared the Apartheid regime’s economic lifeline to the rest of the world more than either policy could have done alone.

No, we’re not suggesting a global boycott of fossil fuels. Rather, we point to the Guardian’s campaign to reiterate that the best and maybe only broadly effective way to reduce fossil fuel demand (which is the point of a boycott) is with a carbon tax. Economists agree on that policy prescription just as strongly as climate scientists agree on the diagnosis. And national-level carbon taxes can be designed to draw our or any nation’s global trading partners into carbon taxing, which means that a move by a big economy to impose a carbon tax will trigger a wave of followers.

So by all means, divest. The cultural and perhaps political opprobrium that divestment can spark is long overdue for the fossil fuels industry. But let’s not assume that divestment alone will break the chains of fossil fuel dependence. Even with the Guardian’s welcome campaign, the world still needs a transparent price on carbon pollution to strangle demand for fossil fuels by replacing them with non-carbon alternatives.


Last modified: March 19, 2015