Market Mechanisms in the Paris Climate Agreement: International Linkage under Article 6.2

The Harvard Project on Climate Agreements hosted a research workshop in Cambridge, Massachusetts, on July 14–15, 2016, the purpose of which was to identify options for elaborating and implementing the Paris Climate Agreement, and to identify policies and institutions that might complement or supplement the United Nations Framework Convention on Climate Change (UNFCCC) process.  We were motivated by our recognition that while the Paris Agreement sets forth an innovative and potentially effective policy architecture for dealing with global climate change, a great deal remains to be done to elaborate the accord, formulate required rules and guidelines, and specify means of implementation.

Participants in the workshop – International Climate Change Policy after Parisincluded twenty-one of the world’s leading researchers focusing on climate-change policy, representing the disciplines of economics, political science, international relations, and legal scholarship. They came from Argentina, Belgium, China, Germany, India, Italy, Norway, the United Kingdom, and the United States.  (A list of workshop participants is here, biographies here, and the agenda here.)

The Harvard Project will next focus on communicating the ideas, insights, and recommendations of workshop participants to climate negotiators and policy makers, in the expectation that they might prove useful in elaborating and implementing the Paris Agreement. Each participant is preparing a brief—based largely on her or his presentation during the workshop. These briefs, together with a workshop summary, will be conveyed to participants in the Twenty-Second Conference of the Parties (COP-22) of the UNFCCC in Marrakech, Morocco in November 2016.  This will be done in meetings with negotiators representing UNFCCC member governments and in a side-event panel at COP-22.

Today I wish to share with readers just one of these draft briefs – namely, my own – on the topic of “International Linkage under Article 6.2 of the Paris Agreement.”

A Key Challenge for Sustained Success of the Paris Agreement

For sustained success of the international climate regime, a key question is whether the Paris Agreement with its Intended Nationally Determined Contributions (INDCs), anchored as they are in domestic political realities, can progressively lead to submissions with sufficient ambition?  Are there ways to enable and facilitate increased ambition over time?

Linkage of regional, national, and sub-national policies can be part of the answer. By “linkage,” I mean connections among policy systems that allow for emission reduction efforts to be redistributed across systems. Such linkage is typically framed as being between two (or more) cap-and-trade systems, but national policies will surely be highly heterogeneous under the Paris climate regime.  Fortunately, research – by Gilbert Metcalf of Tufts University and David Weisbach of the University of Chicago – indicates that linkage between pairings of various types of domestic policy instruments may be feasible.

Linkage and the Paris Agreement

Experience indicates that linkage will bring both merits and concerns in most applications.  To begin with the good news, linkage offers a number of important advantages. First, it offers the possibility of achieving cost savings if marginal abatement costs are heterogeneous across jurisdictions, which they surely are. In addition, linkage can improve the functioning of individual markets by reducing market power, and by reducing price volatility, although we should recognize that price volatility will also be transmitted from one jurisdiction to another by linkage. Finally linkage can allow for the UNFCCC’s important principle of Common but Differentiated Responsibilities (CBDR), but do so without sacrificing cost-effectiveness.

The possibility of linkage also raises concerns, including that there will be distributional impacts within jurisdictions, that is, the creation of both winners and losers. Also, linkage can bring about the automatic propagation from one jurisdiction to another of some design elements, in particular, cost-containment mechanisms, such as banking, borrowing, and price collars. In this and other ways, linkage raises concerns about decreased autonomy.

Linkage under Article 6.2 of the Paris Agreement

It was by no means preordained that the Paris Agreement would allow, let alone encourage, international linkage.  Fortunately, the negotiations which took place in Paris in December, 2015, produced an Agreement that includes in its Article 6.2 the necessary building blocks for linkages to occur.

Under Article 6.2, emissions reductions occurring outside of the geographic jurisdiction of a Party to the Agreement can be counted toward achieving that Party’s Nationally Determined Contribution (NDC) via Internationally Transferred Mitigation Outcomes (ITMOs).  This enables both the formation of “clubs” or other types of coalitions, as well as bottom-up heterogeneous linkage.  Such linkage among Parties to the Agreement would provide for exchanges between compliance entities within the jurisdictions of two different Parties, not simply the government-to-government trading (of Assigned Amounts or AAUs), as was the case with the Kyoto Protocol’s Article 17.

Linkage among Heterogeneous Nationally Determined Contributions

There are three types of heterogeneity which are important in regard to linkage under Article 6.2 of the Paris Agreement. First is heterogeneity among policy instruments. As demonstrated by Metcalf and Weisbach (see above), not only can one cap-and-trade system be linked with another cap-and-trade system, but it is also possible to link a cap-and-trade system with a carbon tax system. In addition, either a cap-and-trade system or a tax system can be linked (via appropriate offsets) with a performance standard in another jurisdiction.  (Linkage with systems employing technology standards are not feasible, however, because such systems are not output-based.)

A second form of heterogeneity that affects linkage and is potentially very important under the Paris Agreement is heterogeneity regarding the level of government action of the relevant jurisdictions. Although the Paris Agreement has as Parties both regional jurisdictions (in the case of the European Union) and national jurisdictions, sub-national jurisdictions are also taking action in some parts of the world. In fact, linkage has already been established between the state of California in the United States and the provinces of Québec and Ontario in Canada.

A third form of relevant heterogeneity is with regards to the NDC targets themselves.  Some are in the form of hard (mass–based) emissions caps, while others are in the form of rate-based emissions caps, either emissions per unit of economic activity, or emissions per unit of output (such as per unit of electricity production). There are also relative mass-based emissions caps in the set of existing NDCs, such as those that are relative to business-as-usual emissions in a specific future year.  Beyond these, there are other parties that have put forward NDCs that do not involve emission caps at all, but rather targets in terms of some other metric, such as the degree of penetration of renewable energy sources.

Combinations of various options under these three forms of heterogeneity yield a considerable variety of types of potential linkages, which may be thought of as the cells of a three-dimensional matrix.  Not all of these cells, however, represent linkages which are feasible, let alone desirable.

The Path Ahead – Key Issues and Questions

There are a substantial number of issues that negotiators will eventually need to address, and likewise, there are a set of questions that researchers (including within the Harvard Project on Climate Agreements) can begin to address now. Among the key issues for negotiators will be the necessity to develop accounting procedures and mechanisms. Also, it will be important to identify means for the ITMOs to be tracked in order to avoid double-counting of emissions reductions. And a broader question is whether and how the UNFCCC Secretariat or some other designated institution will provide any oversight that may be required.

For research, three questions stand out.  First, among pairings from the (3-D matrix) set of instrument–jurisdiction–target combinations that emerge from the three types of heterogeneity identified above, which linkages will actually be feasible?  Second, within this feasible set, are some types of linkages feasible, but not desirable? And third, what accounting treatments and tracking mechanisms will be necessary for these various types of linkages?  Future research will need to focus on these and related questions in order to achieve the potential benefits of Article 6.2 of the Paris Agreement.  Please stay tuned as this work develops.

Crude Oil Prices, Climate Change, and Global Welfare

A few weeks ago, I participated in a panel session titled, “The Remarkable Transformation of the Energy Sector: Does it Also Transform Our World.” The motivating question was: “Is the dramatic decline in oil prices a complete gift to the West because of the enormous funds being saved, or is it an unintended Trojan horse because development of renewable energy as well as new fossil-fuel sources will decline in the West, posing longer new challenges?”

The other members of the panel – from private industry – had vastly more expertise (and relevant insights) on fossil-fuel markets, but here’s what I had to say. This is hardly at the sweet spot of my professional competence, so I welcome your comments and corrections! In general, how would you answer that question?


I start (and started) from the premise that the dramatic decline in crude oil prices that took place from August, 2014 ($96/barrel), to March, 2015 ($44/barrel), was due – on the one hand – to decreased demand, a function of slow economic growth in Asia, Europe, and elsewhere, endogenous, price-driven technological change leading to greater fuel efficiency, and policy-driven technological change that also has been leading to greater fuel efficiency, such as more stringent Corporate Average Fuel Economy (CAFE) standards in the United States; and – on the other hand – was due to increased supply, partly a function of the growth of unconventional (tight) U.S. oil production (a product of the combination of two technologies – horizontal drilling and hydraulic fracturing).  And, in the presence of all of this, Saudi Arabia decided not to restrict its output to prop up prices.

[Before proceeding, I should note that since May of this year, crude oil prices have increased by about 30% from their March low, but as of May ($60/barrel) are still far below their August 2014 level.]


When one examines virtually any significant price change from an economic perspective, there inevitably seems to be both good news and bad news. So with the fall in crude oil prices.

The Bad News

First of all, I assume that low crude oil prices are problematic for the economic and political stability of some of the oil-producing/exporting countries, including Saudi Arabia, Russia, Venezuela, and Nigeria.  (For details, see Bordoff and Losz 2015, below.)

Second, it’s frequently been asserted that low oil prices are bad news for the development of alternative forms of energy, including renewable sources. Of course, in the United States, there isn’t much effect on electricity generation from renewable (wind and solar), because in the U.S. electricity sector, renewable supplies compete with coal and natural gas, not with fuel oil (but in other countries, which use more fuel oil for electricity generation than we do, there can be a disincentive for renewable dispatch – and hence development).

Third, there can be – indeed, has been – a major impact in the U.S. motor fuels sector, where the market for biofuels (mainly ethanol) is negatively affected by low conventional gasoline prices. However, these impacts must be somewhat muted by public policies, which directly or indirectly subsidize (or, in fact, require) the use of biofuels.

Fourth, low gasoline prices have resulted in decreased demand by consumers for motor vehicles with high fuel efficiency, and SUV and pickup truck sales have rebounded from previous lows. But these effects are also muted, to some degree, by public policies, including U.S. CAFE standards.   Finally, low gasoline prices also have short-term effects in the form of more driving and fuel use by the existing fleet of motor vehicles, which is bad news in terms of emissions (and congestion).

Differences across Sectors

Before turning to the “good news” about low crude oil prices (and there surely is good news), it’s worthwhile noting that whether individual businesses find these low prices to be good or bad depends largely upon the economic sector in which they operate. For example, whereas commercial airlines are finally making profits, due to the low price of jet fuel (their most important variable operating cost), manufacturers of commercial aircraft will see lower demand for new planes if low jet fuel prices become the long-term norm. The primary factor driving the larger airlines to replace aircraft in their fleets is the lower operating costs due to the much greater fuel efficiency of new models.

And, of course, low oil prices are systematically bad news for oil producers, including the major U.S. companies.

The Good News

Finally, here is the upside of these significant changes in crude oil markets.

Low oil prices are unambiguously good for aggregate global welfare. This includes consumers in the United States, Europe, Japan, and South Korea. And, at least temporarily, OPEC seems to have lost its ability to set a price floor.

Low oil prices mean an increase in consumers’ disposable income, amounting to nearly $2,500 per U.S. household annually, according to Stephen Brown (see below).  If we subtract the income losses to U.S. oil producers, the net gain per U.S. household amounts to a bit more than $800 per year, with gains accruing disproportionately to low-income households.

Turning to the environmental realm, there is also good news, or at least the possibility of good news. An opportunity for new, sensible energy and climate change policies has emerged with these low oil prices.

First, now is the time to reduce – or better yet, phase out – costly and inefficient fuel subsidies, which exist in many parts of the world, particularly in developing countries.

Second, with gasoline prices relatively low – and natural gas supplies holding down electricity prices, at least in the United States – there has never been a better time to introduce progressive climate policies in the form of carbon-pricing, whether via carbon taxes or through carbon cap-and-trade. Unfortunately, none of us should hold our breath waiting for that to happen.


For further reading, I recommend:

Bordoff, Jason, and Akos Losz.  “Oil Shock: Decoding the Causes and Consequences of the 2014 Oil Price Drop.”  Horizons, Spring 2015, Issue No. 3, pp. 190-206.

Brown, Stephen P. A.  “Falling Oil Prices: Implications in the United States.” Resources, Number 189.  Washington:  Resources for the Future, 2015, pp. 40-44.

The Second Term of the Obama Administration

In his inaugural address on January 21st, President Obama surprised many people – including me – by the intensity and the length of his comments on global climate change.  Since then, there has been a great deal of discussion in the press and in the blogosphere about what climate policy initiatives will be forthcoming from the administration in its second term.

Given all the excitement, let’s first take a look at the transcript of what the President actually said on this topic:

            We will respond to the threat of climate change, knowing that the failure to do so would betray our children and future generations. Some may still deny the overwhelming judgment of science, but none can avoid the devastating impact of raging fires, and crippling drought, and more powerful storms.  The path towards sustainable energy sources will be long and sometimes difficult. But American cannot resist this transition.  We must lead it.  We cannot cede to other nations the technology that will power new jobs and new industries.  We must claim its promise. That’s how we will maintain our economic vitality and our national treasure, our forests and waterways, our crop lands and snow capped peaks.  That is how we will preserve our planet, commanded to our care by God.

Strong and plentiful words.  Although I was certainly surprised by the strength and length of what the President said in his address, I confess that it did not change my thinking about what we should expect from the second term.  Indeed, I will stand by an interview that was published by the Harvard Kennedy School on its website five days before the inauguration (plus something I wrote in a previous essay at this blog in December, 2012).  Here it is, with a bit of editing to clarify things, and some hyperlinks inserted to help readers.

The Second Term: Robert Stavins on Energy and Environmental Policy

January 16, 2013

By Doug Gavel, Harvard Kennedy School Communications

President Obama’s second term in office began on Inauguration Day, January 21st, and the list of policy challenges facing his administration is daunting. Aside from the difficult task of addressing the nation’s economic woes, the president and his administration will also deal with the increasing complexities of global climate change, a rapidly changing energy market, entitlement and tax reform, healthcare reform, and the repercussions from the still simmering “Arab Spring.” Throughout this month, we will solicit the viewpoints of a variety of HKS faculty members to provide a range of perspectives on the promise and pitfalls of The Second Term.

We spoke with Robert Stavins, Albert Pratt Professor of Business and Government, and Director of the Harvard Environmental Economics Program, about energy and environmental policy issues the president will face in the next four years.

Q: What are the top priorities for a second Obama administration in energy and environmental policy?

A: The Obama administration faces a number of impending challenges in the energy and environmental policy realm in its second term, which I would characterize – in very general terms – as finding balance among three competing factors: (1) demands from some constituencies for more aggressive environmental policies; (2) demands from other constituencies – principally in the Congress – for progress on so-called “energy security;” and (3) recognition that nothing meaningful is likely to happen if the country’s economic problems are not addressed.

Q: What will be the potential challenges/roadblocks in the way of implementing those top priorities?

A: The key challenge the administration faces in its second term as it attempts to achieve some balance among these three competing objectives is the reality of a very high degree of political polarization in the two houses of Congress.

The numbers are dramatic.  For example, when the Clean Air Act Amendments of 1990 that established the landmark SO2 allowance trading system were being considered in the U.S. Congress, political support was not divided on partisan lines. Indeed, environmental and energy debates from the 1970s through much of the 1990s typically broke along geographic lines, rather than partisan lines, with key parameters being degree of urbanization and reliance on specific fuel types, such as coal versus natural gas. The Clean Air Act Amendments of 1990 passed the U.S. Senate by a vote of 89-11 with 87 percent of Republican members and 91 percent of Democrats voting yea, and the legislation passed the House of Representatives by a vote of 401-21 with 87 percent of Republicans and 96 percent of Democrats voting in support.

But, 20 years later when climate change legislation was receiving serious consideration in Washington, environmental politics had changed dramatically, with Congressional support for environmental legislation coming mainly to reflect partisan divisions. In 2009, the U.S. House of Representatives passed the American Clean Energy and Security Act of 2009 (H.R. 2454), often known as the Waxman-Markey bill, that included an economy-wide cap-and-trade system to cut carbon dioxide (CO2) emissions. The Waxman-Markey bill passed by a narrow margin of 219-212, with support from 83 percent of Democrats, but only 4 percent of Republicans. (In July 2010, the U.S. Senate abandoned its attempt to pass companion legislation.) Political polarization in the Congress (and the country) has implications far beyond energy and environmental policy, but it is particularly striking in this realm.

Q: In the Obama administration’s second term, are there openings/possibilities for compromises in those areas?

A: It is conceivable – but in my view, unlikely – that there may be an opening for implicit (not explicit) “climate policy” through a carbon tax. At a minimum, we should ask whether the defeat of cap-and-trade in the U.S. Congress, the virtual unwillingness over the past 18 months of the Obama White House to utter the phrase “cap-and-trade” in public, and the defeat of Republican Presidential candidate Mitt Romney indicate that there is a new opening for serious consideration of a carbon-tax approach to meaningful CO2 emissions reductions in the United States.

First of all, there surely is such an opening in the policy wonk world. Economists and others in academia, including important Republican economists such as Harvard’s Greg Mankiw and Columbia’s Glenn Hubbard, remain enthusiastic supporters of a national carbon tax. And a much-publicized meeting in July, 2012, at the American Enterprise Institute in Washington, D.C. brought together a broad spectrum of Washington groups – ranging from Public Citizen to the R Street Institute – to talk about alternative paths forward for national climate policy. Reportedly, much of the discussion focused on carbon taxes.

Clearly, this “opening” is being embraced with enthusiasm in the policy wonk world. But what about in the real political world? The good news is that a carbon tax is not “cap-and-trade.” That presumably helps with the political messaging! But if conservatives were able to tarnish cap-and-trade as “cap-and-tax,” it surely will be considerably easier to label a tax – as a tax! Also, note that President Obama’s silence extends beyond disdain for cap-and-trade per se. Rather, it covers all carbon-pricing regimes.

So as a possible new front in the climate policy wars, I remain very skeptical that an explicit carbon tax proposal will gain favor in Washington. Note that the only election outcome that could have lead to an aggressive and successful move to a meaningful nationwide carbon pricing regime would have been: the Democrats took back control of the House of Representatives, the Democrats achieved a 60+ vote margin in the Senate, and the President was reelected. Only the last of these happened. It’s not enough.

A more promising possibility – though still unlikely – is that if Republicans and Democrats join to cooperate with the Obama White House to work constructively to address the short-term and long-term budgetary deficits the U.S. government faces, and if as part of this they decide to include not only cuts in government expenditures, but also some significant “revenue enhancements” (the t-word is not allowed), and if (I know, this is getting to be a lot of “ifs”) it turns out to be easier politically to eschew increases in taxes on labor and investment and turn to taxes on consumption, then there could be a political opening for new energy taxes, even a carbon tax.

Such a carbon tax – if intended to help alleviate budget deficits – could not be the economist’s favorite, a revenue-neutral tax swap of cutting distortionary taxes in exchange for implementing a carbon tax. Rather, as a revenue-raising mechanism – like the Obama administration’s February 2009 budget for a 100%-auction of allowances in a cap-and-trade scheme – it would be a new tax, pure and simple. Those who recall the 1993 failure of the Clinton administration’s BTU-tax proposal – with a less polarized and more cooperative Congress than today’s – will not be optimistic.

Nor is it clear that a carbon tax would enjoy more support in budget talks than a value added tax (VAT) or a Federal sales tax. The key question is whether the phrases “climate policy” and “carbon tax” are likely to expand or narrow the coalition of support for an already tough budgetary reconciliation measure.  The key group to bring on board will presumably be conservative Republicans, and it is difficult to picture them being more willing to break their Grover Norquist pledges because it’s for a carbon tax.

What remains most likely to happen is what I’ve been saying for several years, namely that despite the apparent inaction by the Federal government, the official U.S. international commitment — a 17 percent reduction of CO2 emissions below 2005 levels by the year 2020 – is nevertheless likely to be achieved!  The reason is the combination of CO2 regulations which are now in place because of the Supreme Court decision [freeing the EPA to treat CO2 like other pollutants under the Clean Air Act], together with five other regulations or rules on SOX [sulfur compounds], NOX [nitrogen compounds], coal fly ash, particulates, and cooling water withdrawals. All of these will have profound effects on retirement of existing coal-fired electrical generation capacity, investment in new coal, and dispatch of such electricity.

Combined with that is Assembly Bill 32 (AB 32) in the state of California, which includes a CO2 cap-and-trade system that is more ambitious in percentage terms than Waxman-Markey was in the U.S. Congress, and which became binding on January 1, 2013.  Add to that the recent economic recession, which reduced emissions. And more important than any of those are the effects of developing new, unconventional sources of natural gas in the United States on the supply, price, and price trajectory of natural gas, and the consequent dramatic movement that has occurred from coal to natural gas for generating electricity.  In other words, there will be actions having significant implications for climate, but most will not be called “climate policy,” and all will be within the regulatory and executive order domain, not new legislation.

Q: Are there lessons that a second Obama administration can draw upon from the first administration, or from history, when constructing its energy & environmental policy over the next four years?

A: It will take a great deal of dedicated effort and profound luck to find political openings that can bridge the wide partisan divide that exists on climate change policy and other environmental issues. Think about the following. Nearly all our major environmental laws were passed in the wake of highly publicized environmental events or “disasters,” including the spontaneous combustion of the Cuyahoga River in Cleveland, Ohio, in 1969, and the discovery of toxic substances at Love Canal in Niagara Falls, New York, in the mid-1970s. But note that the day after the Cuyahoga River caught on fire, no article in The Cleveland Plain Dealer commented that the cause was uncertain, that rivers periodically catch on fire from natural causes. On the contrary, it was immediately apparent that the cause was waste dumped into the river by adjacent industries. A direct consequence of the observed “disaster” was, of course, the Clean Water Act of 1972.

But climate change is distinctly different. Unlike the environmental threats addressed successfully in past U.S. legislation, climate change is essentially unobservable to the general population. We observe the weather, not the climate.  Notwithstanding last year’s experience with Super Storm Sandy, it remains true that until there is an obvious, sudden, and perhaps cataclysmic event – such as a loss of part of the Antarctic ice sheet leading to a dramatic sea-level rise – it is unlikely that public opinion in the United States will provide the tremendous bottom-up demand that inspired previous congressional action on the environment over the past forty years.

That need not mean that there can be no truly meaningful, economy-wide climate policy (such as carbon-pricing) until disaster has struck.  But it does mean that bottom-up popular demand may not come in time, and that instead what will be required is inspired leadership at the highest level that can somehow bridge the debilitating partisan political divide.

Postscript:  Please note that the Kennedy School series on the second term of the Obama administration also includes an interview with my colleague, Professor Joseph Aldy, offering his own views on potential environmental policy developments in the next four years.