See how a carbon tax works and why taxing carbon pollution must be the central policy to combat climate change:

Earth’s climate is changing in costly and painful ways. 2014 was the globe’s hottest year on record, and the dozen warmest have all come after 1997, as this graphic shows all too clearly.

Globe not warming? Look again.
Globe not warming? Look again. CO2 from fossil fuel-burning not the cause? Click here.

Yet the transition from climate-damaging fossil fuels to energy efficiency, renewable sunlight and wind energy is slow and halting. The Number One obstacle is that the market prices of coal, oil and gas don’t include the true costs of carbon pollution. A briskly rising U.S. carbon tax will transform energy investment, re-shape consumption, and sharply reduce the carbon emissions that are driving global warming.

  • A carbon tax is an “upstream” tax on the carbon contents of fossil fuels (coal, oil and natural gas) and biofuels.
  • A carbon tax is the most efficient means to instill crucial price signals that spur carbon-reducing investment. Download our spreadsheet (Excel file) to input your own tax levels and see how fast U.S. emissions will fall.
  • A carbon tax will raise fossil fuel prices — that’s the point. The impact on households can be softened through “dividends” (revenue distributions) and/or reducing other taxes that discourage hiring and investing (“tax-shifting or swapping”).
  • Carbon taxing is an antidote to rigged energy pricing that helps fossil fuels destabilize earth’s climate. Unlike cap-and-trade, carbon taxes don’t create complex and easily-gamed“carbon markets” with allowances, trading and offsets.

Latest from the Blog:

Here’s What’s New in CTC’s Carbon Tax Spreadsheet Model

June 27, 2015 by Charles Komanoff Comments (0)

We’ve just posted an update to our spreadsheet model — our powerful but easy-to-use tool for predicting future emissions and revenues from possible U.S. carbon taxes. We say taxes, plural, because the model accepts any carbon tax trajectory you feed it and spits out estimated nationwide emission reductions and revenue generation, year by year. Here’s a rundown of what’s new in the update.

    1. A year of new data: The most obvious change is the addition of 2014 baseline data on energy use, CO2 emissions and emission intensity for each of the model’s seven sectors.

    Our spreadsheet model lets you compare different carbon tax trajectories.

    Our spreadsheet model lets you compare different carbon tax trajectories.

    2. Smoothing the carbon tax impact: A new feature lets users smooth the impact of the tax to reflect real-world lags in households’ and businesses’ adaptation to more-expensive fossil fuels. (You get to set the adaptation “ceiling” rate; any excess gets carried over to future years.) This feature is helpful for trajectories like the Whitehouse-Schatz bill, whose rate starts with a bang at $45 per ton of carbon dioxide but then rises only slowly. Under our default setting, the reductions from the $45/ton initial charge are spread over four years rather than, unrealistically, assigned to the first year.

    3. Future baseline is calibrated to official forecast: We tweaked a few model parameters to make our 2040 emissions forecast without a carbon tax match the analogous forecast in the Energy Information Administration’s “Annual Energy Outlook.” This allows for apples-to-apples comparisons with other models that are explicitly calibrated to the EIA/AEO forecast.

    4. Demand vs. Supply side impacts: A new section at the bottom of the Summary page reports each sector’s CO2 reductions that arise from changes in the carbon intensity of fuels vis-à-vis reductions from reduced energy usage (e.g., lower electricity purchases, less driving or flying). Under the default carbon tax — the tax proposed by Washington Rep. Jim McDermott — an estimated 53% of the total projected CO2 reductions are on the supply side (i.e., due to decarbonization), while the remaining 47% come about through reduced demand. (This finding is helpful for understanding that subsidies-only policies miss out on huge CO2 reductions; indeed, they undercut reductions from decarbonization by stimulating energy usage through lowered energy prices, as we pointed out in our 2014 comments to the Senate Finance Committee.)

    5. Snapshot pushed back to 2030: We’ve changed 2020 to 2030 as the “snapshot” year on the Summary page. Our other gauge for the carbon tax’s emissions impact — the “10th year” output box — remains, as do our year by year forecasts of emissions, revenue, and oil savings.

    6. (Slightly) lowered gasoline price-elasticity: As part of our model update we ran regressions on U.S. gasoline consumption back to 1960 to recalibrate our assumptions on the extent to which gasoline use tracks economic growth and/or falls when pump prices rise faster than general inflation. The result is that we scaled back our gasoline price-elasticity assumption slightly, to 0.35 (from 0.40 previously). We wrote up the analysis — it’s toward the back, in the “Parameters” tab — so you economists out there can vet our thought processes.

    7. Spruced-up presentation: We’ve jazzed up some graphs and generally made the spreadsheet pages easier to follow.

    So go ahead and download the spreadsheet — here’s the link again — and give it a twirl. See for yourself the relative efficacy of a carbon tax trajectory that increases by a fixed amount each year, as does the McDermott tax, vs. one that starts high but rises only by small, percentage-driven amounts, as does the Whitehouse-Schatz tax. And as you work (play?) with the model, jot down your thoughts so you can tell us what works and what needs improving. Thank you.


Who’s “Out of Step” on Climate — Pope Francis or Harvard Expert?

June 19, 2015 by James Handley and Charles Komanoff Comments (5)

New York Times climate reporter Coral Davenport writes today that Pope Francis’s warning against cap-and-trade as a tool to address the climate crisis creates a “paradox”:

[W]here Francis’ environmental and economic agendas meet, he leaves something of a paradox. . . While urging swift action to curb the burning of fossil fuels that have powered economies since the Industrial Revolution, he also condemns the trading of carbon-emission credits, saying it merely creates new forms of financial speculation and does not bring about “radical change.” But carbon trading is the policy most widely adopted by governments to combat climate change, and it has been endorsed by leading economists as a way to cut carbon pollution while sustaining economic growth.

With due respect to Davenport as well as Robert Stavins, the Harvard climate economist whose concerns figure prominently in her story, there is no paradox. Francis’s encyclical, On Care For Our Common Home, doesn’t muddy the climate change debate because a carbon tax, not cap-and-trade, is economists’ preferred policy tool for curbing carbon pollution. Francis-cap-tradeFrancis criticizes emissions trading on three grounds: First, trading carbon allowances allows traders to profit from the climate crisis — indeed, it’s designed to do that. Second, “offsets” that are virtually hard-wired into cap-and-trade shift the burden of pollution to developing countries. Third, cap-and-trade with offsets absolves the wealthy of responsibility to rein in their carbon-intensive lifestyles. In Francis’s own words:

The strategy of buying and selling carbon credits can lead to a new form of speculation which would not help reduce the emission of polluting gases worldwide. This system seems to provide a quick and easy solution under the guise of a certain commitment to the environment, but in no way does it allow for the radical change which present circumstances require. Rather, it may simply become a ploy which permits maintaining the excessive consumption of some countries and sectors. [171]

What, then, does Francis demand? That societies internalize the costs of pollution, especially climate pollution:

[O]nly when the economic and social costs of using up shared environmental resources are recognized with transparency and fully borne by those who incur them, not by other peoples or future generations, can those actions be considered ethical. [195]

A reference in that passage attributes Francis’s calls for polluters to pay “the economic and social costs” they incur to his predecessor, Pope Benedict. (Both pontiffs presumably intended “impose” rather than “incur,” i.e., for costs to be borne by those who impose them, but no matter.) Those resources surely include clean air. The new encyclical thus aligns the Catholic Church with the century-old “Pigovian” tradition of economists urging policies to internalize costs. Francis-carbon4-taxNevertheless, in an email quoted by Davenport, Stavins brands Francis as “out of step with … informed policy analysts around the world,” in effect labeling the Pope as economically-illiterate and naïve:

“I respect what the pope says about the need for action, but this is out of step with the thinking and the work of informed policy analysts around the world, who recognize that we can do more, faster, and better with the use of market-based policy instruments — carbon taxes and/or cap-and-trade systems,” Robert N. Stavins, the director of the environmental economics program at Harvard, said in an email.

That Stavins is the lone environmental economist quoted in Davenport’s piece did not deter her from claiming that “environmental economists criticized the encyclical’s condemnation of carbon trading, seeing it as part of a radical critique of market economies.” Hardly. The Pope, like legions of environmental activists and economists worldwide, has seen the shams of emissions trading and carbon “speculation” for what they are. Read more…


Earth Institute Chief Trashes the Carbon Tax

June 12, 2015 by Daniel Lazare Comments (2)

Steven Cohen, executive director of Columbia University’s prestigious Earth Institute, recently weighed in on the carbon-tax debate in the Huffington Post. The results are breathtaking – and not in a good way.

Cohen’s June 8 screed, “A Carbon Tax Is Not Feasible or Practical,” was a riposte to a New York Times editorial two days earlier endorsing a carbon tax as “one of the best policies available” to address global warming. The Times is wrong, says Cohen, as he proceeds to lay out a multi-count indictment. Among his anti-CT arguments are the following:

1. Carbon taxes are politically infeasible: Given the system’s deep hostility to tax hikes, “the space between the carbon tax as a policy idea and the reality of American politics is too vast to overcome. For better or worse, here in America we are in a period of tax policy paralysis that is unlikely to be surmounted anytime soon.”

2. Carbon taxes are unfair: They “cause people on the lower end of the economic ladder to pay a higher portion of their income on energy,” while corrective measures aimed at redistributing the costs “are far from simple to implement, might stigmatize recipients, and would become easy and obvious political targets.”

3. Contrary to The Times, carbon taxes are unequal to the problem of climate change because they would founder on the shoals of international politics: “China and India would need to go along, and given the urgency of their energy and development needs, it is difficult to imagine that they would agree to such a measure.”

4. Carbon taxes are anti-urban: “I sometimes think the push for a carbon tax comes out of an early 20th century environmentalist mindset that scolds people for consumption and living in evil, immoral cities.”

5. Finally, carbon taxes are unnecessary since tax breaks can be just as easily used to encourage alternative energy development: “Why waste time and effort on an infeasible policy that will never happen? Why not devote time and effort to building a real partnership between the public and private sector to create a sustainable economy?”

NYT-CohenCareful readers will notice that the first two items are variations on a theme, which is to say the futility of relying on the U.S. political system to pass a well-crafted carbon-tax plan that discourages fossil fuels without burdening workers and the poor. The same can be said for number three, which is about the inability of a beggar-thy-neighbor international system to institute significant reform. Whether the fault lies with Washington, Beijing, or New Delhi, Cohen argues, the point remains that politicians of all nationalities are too selfish and shortsighted to deal intelligently with a carbon tax, so it’s best to forget the whole thing.

Charges four and five are different, so let’s tackle those first. Read more…


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

June 8, 2015 by James Handley Comments (11)

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…


Book Review: “Climate Shock”

May 26, 2015 by Rachael Sotos Comments (5)

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…