Climate 411

The Silver Bullet Of Climate Change Policy

(This post originally appeared on Forbes)

By Bob Litterman and Gernot Wagner

Whenever the conversation turns to climate change, someone is sure to opine that there’s no silver bullet. The issue is simply too complex to have one solution. When you focus on all the changes that need to occur to reduce greenhouse gas emissions globally it seems like a multifaceted approach is the only way forward.

Most of the world’s vexing problems share that feature. Mideast peace, nuclear non-proliferation, Eurozone stability, and plenty of other national security problems have no single right plan of attack. Some past plans might have brought us tantalizingly close to a seeming solution, but then reality started interfering once again, reconfirming the complexity of it all.

Climate change must surely be in that category. No single country, no single technology, no single approach can seemingly solve this one for us once and for all. Picking a single technology will almost inevitably end in some form of disappointment. Bureaucrats, the saying goes, ought not to try to pick winners. Leave that to venture capitalists for whom failure is a way of life. For every Apple and Facebook, there are dozens who never make it out of the garage. And clean technology doesn’t yet even have a single Apple and Facebook as the standout approach revolutionizing the field.

Source: NYU

It turns out, though, that how you frame the issue is crucial. If you think like an engineer there are dozens of challenges. If you think like an economist, there is one. It’s guiding the ‘invisible hand’. How can you create the appropriate incentive to decrease the pollution that’s causing climate change? For that, the government need not be in the business of picking winners at all. What it should—and can—do is identify the loser that’s been clear for decades: greenhouse gas pollution. And the solution is equally clear: create incentives to reduce emissions by pricing it. If we make this one change, most other actions that are needed will follow.

That’s what the European Union has done by capping carbon emissions from its energy sector, including large industrials, covering almost half of total carbon emissions. That’s what California is doing with over 80 percent of its total global warming emissions. It’s what China is experimenting with in seven city and regional trials, including in Beijing and Shanghai. All these systems put a price on greenhouse gas pollution.

On the other side of the ledger, there are still much larger incentives to consume fossil fuels in many other countries. The International Energy Agency estimates that global subsidies are well over $500 billion. These subsidies, which incentivize emissions, sadly dwarf the paltry incentives to reduce them. Free marketeers, small government advocates, and others who dislike distorting government subsidies should be appalled at the tax money poured into fossil fuels.

There’s one simple principle that’s been around in economics for so long that no economist worth his or her degree would question the conclusion: increase the price, watch the quantity demanded go down. It’s such a universal truism that economists call it the “Law of Demand.” Generations of graduate students have estimated the effects of price on demand for anything from the generic widget to demand for car miles driven. People may be irrational at times, but one thing that we know for sure is that they respond to incentives.

Everything we know from decades of the study of human behavior would lead us to believe that carbon pollution will go down as the price on emissions increases. The only interesting question is by how much.

The prescription then for anyone seriously concerned about climate change is simple: price carbon to the point where its now unpriced damages are incorporated into the price, and get out of the way. It’s simple. It works. It’s conservative to the core.

It’s also a silver bullet solution if there ever was one.

Bob Litterman is a Partner at Kepos Capital, LP. Gernot Wagner is a senior economist at the Environmental Defense Fund.

Posted in Economics, Greenhouse Gas Emissions, Policy / Read 1 Response

Why the cost of carbon pollution is both too high and too low

(This post originally appeared on EDF Voices)

Tell someone you are a “climate economist,” and the first thing you hear after the slightly puzzled looks subside is, “How much?” Show me the money: “How much is climate change really costing us?”

Here it is: at least $40.

That, of course, isn’t the total cost, which is in the trillions of dollars. $40 is the cost per ton of carbon dioxide pollution emitted today, and represents the financial impacts of everything climate change wreaks: higher medical bills, lost productivity at work, rising seas, and more. Every American, all 300 million of us, emit around twenty of these $40-tons per year.

The number comes from none other than the U.S. government in an effort to uncover the true cost of carbon pollution. This exercise was first conducted in 2010. It involved a dozen government agencies and departments, several dozen experts, and a fifty-page, densely crafted “technical support document,” replete with some seventy, peer-reviewed references and an even more technical appendix.

Cass Sunstein, the Harvard legal scholar of Nudge fame, who was co-leading the process for the White House at the time, recently declared himself positively surprised how the usual interest-group politics were all-but absent from the discussions throughout that process. This is how science should be done to help guide public policy.

The cost of carbon pollution is too low

The number originally reached in 2010 wasn’t $40. It was a bit more than half as much. What happened? In short, the scientific understanding of the impacts of rising seas had advanced by so much, and the peer-reviewed, economic models had finally caught up to the scientific understanding circa 2007, that a routine update of the cost of carbon number resulted in the rather dramatic increase to near $40 per ton. (There are twenty pages of additional scientific prose, if you want to know the details.)

In other words, we had been seriously underestimating the cost of climate change all along. That’s the exact opposite of what you hear from those who want to ignore the problem, and the $40 itself is still woefully conservative. Some large companies, including the likes of Exxon, are voluntarily using a higher price internally for their capital investment decisions.

And everything we know about the science points to the fact that the $40 figure has nowhere to go but up. The more we know, the higher the costs. And even what we don’t knowpushes the costs higher still.

Howard Shelanski, Sunstein’s successor as the administrator of the Office of Information and Regulatory Affairs (OIRA, pronounced “oh-eye-ruh”), has since presided over a further update of the official number. In fact, this one didn’t incorporate any of the latest science. It was simply a minor technical correction of the prior update, resulting in a $1 revision downward. (The precise number is now $37, though I still say $40 at cocktail parties, to avoid a false sense of precision. Yes, that’s what a climate economist talks about at cocktail parties.)

And once again, it all demonstrated just how science ought to be done: Sometimes it advances because newer and better, peer-reviewed publications become available. Sometimes it advances because someone discovers and fixes a small mathematical error.

Your input is needed

While announcing the correction, Shelanski added another layer of transparency and an opportunity for further refinements of the numbers: a formal call for public comments on the way the cost of carbon figure is calculated, open through January 27 February 26th.

We are taking this opportunity seriously. EDF, together with our partners at the Natural Resource Defense Council, New York University School of Law’s Institute for Policy Integrity, and the Union of Concerned Scientists, is submitting formal, technical comments in support of the administration’s use of the cost of carbon pollution number as well as recommending further revisions to reflect the latest science.

The bottom line, as economists like to put it, is that carbon pollution costs society a lot of money. So as the technical experts trade scientific papers, you can help by reminding our leaders in Washington that we need strong, science-based climate policies.

Update (on January 24th): The official comment period just was extended for another month, through February 26th. More time to show your support.

Posted in Economics, Greenhouse Gas Emissions, Science, Setting the Facts Straight / Read 1 Response

Correcting the maths of the “50 to 1 Project”

A nine-minute video, released earlier this fall, argues that climate mitigation is 50 times more expensive than adaptation. The claims are based on calculations done by Christopher Monckton. We analyzed the accompanying “sources and maths” document. In short, the author shows a disconcerting lack of understanding of climate science and economics:

  1. Fundamental misunderstanding of basic climate science: Pre-industrial levels of carbon dioxide (CO2) were at around 280 parts per million (ppm).[i] One of the most commonly stated climate policy goals is to keep concentrations below 450 ppm CO2. Monckton, oddly, adds 280 and 450 to get to 730 ppm as the goal of global stabilization efforts, making all the rest of his calculations wildly inaccurate.
  2. Prematurely cutting off analysis after ten years: Monckton calculates the benefits of the carbon tax over a ten-year time horizon. That is much too short to see the full effects of global warming or of the policy itself. Elevated carbon levels persist for hundreds to thousands of years.[ii]
  3. Erroneously applying Australian “cost-effectiveness” calculation to the world: This may be the most troubling aspect from an economist’s point of view. Monckton first calculates the effect of the Australia-only tax on global temperatures, which is unsurprisingly low, as Australia accounts for only 1.2% of world emissions. Next, he calculates the tax’s resulting “cost-effectiveness” — defined as the Australian tax influencing global temperatures. No surprise once again, that influence is there, but Australia alone can’t solve global warming for the rest of us. Then, Monckton takes the Australia-only number and scales it to mitigate 1ºC globally, resulting in a purported cost of “$3.2 quadrillion,” which he claims is the overall global “mitigation cost-effectiveness.” But this number simply represents the cost of avoiding 1ºC of warming by acting in Australia alone. Monckton has re-discovered the fact that global warming is a global problem! The correct calculation for a globally applied tax would be to calculate cost-effectiveness on a global level first. If Australia’s carbon price were to be applied globally, it would cut much more pollution at a much lower cost. And that, of course, is very much the hope. Australia, California, and the European Union are called “climate leaders” for a reason. Others must follow.

What’s the real cost of cutting carbon? The U.S. government’s estimate of the cost of one ton of CO2 pollution released today is about $40.[iii] That’s also the optimal price to make sure that each of us is paying for our own climate damages. Any policy with a lower (implied) carbon price—including the Australian tax—easily passes a benefit-cost test.

With all due respect Lord Monckton, 3rd Viscount of Brenchley, your maths are way off.


[i] “Summary for Policymakers,” IPCC Fifth Assessment Report, Working Group I (2013).

[ii] Results differ across scenarios, but a rough rule of thumb suggests that approximately 70% of the ‘peak enhancement level’ over the preindustrial level of 280 ppm perseveres after 100 years of zero emissions, while approximately 40% of the ‘peak enhancement level’ over the preindustrial level of 280 ppm persevered after 1,000 years of zero emissions (Solomon, Susan, Gian-Kasper Plattner, Reto Knutti and Pierre Friedlingstein, “Irreversible climate change due to carbon dioxide emissionsProceedings of the National Academy of Sciences 106, no. 6 (2009): 1704-1709). Note that this refers to the net increase in carbon dioxide in the atmosphere, not the exact molecule. Archer, David, Michael Eby, Victor Brovkin, Andy Ridgwell, Long Cao, Uwe Mikolajewicz, Ken Caldeira et al. “Atmospheric lifetime of fossil fuel carbon dioxide.” Annual Review of Earth and Planetary Sciences 37 (2009): 117-134 discusses these two often confused definitions for carbon’s ‘lifetime,’ and concludes that 20-40% of excess carbon levels remain hundreds to thousands of years (“2-20 centuries”) after it is emitted. Each carbon dioxide molecule has a lifetime of anywhere between 50 to 200 years, according to the U.S. Environmental Protection Agency’s “Overview of Greenhouse Gases: Carbon Dioxide Emissions.” The precise number is under considerable scientific dispute and surprisingly poorly understood. (Inman, Mason, “Carbon is forever,” Nature Reports Climate Change 20 November 2008)

[iii] The precise value presented in Table 1 of the Technical Update of the Social Cost of Carbon for Regulatory Impact Analysis Under Executive Order 12866 for a ton of carbon dioxide emitted in 2015, using a 3% social discount rate increased is $38. For 2020, the number is $43; for 2030, the number increases to $52. All values are in inflation-adjusted 2007 dollars. For a further exploration of this topic, see Nordhaus, William D. The Climate Casino: Risk, Uncertainty, and Economics for a Warming World. Yale University Press (2013) as only one of the latest examples summarizing this kind of analysis. Nordhaus concludes that the optimal policy, one that maximizes net benefits to the planet, would spend about 3% of global GDP.

Many thanks to Michelle Ho for excellent research assistance.

Posted in Basic Science of Global Warming, Economics, International / Comments are closed

Geoengineering: Ignore Economics and Governance at Your Peril

How serious is global warming? Here’s one indication: the first rogue entrepreneurs have begun testing the waters on geoengineering, as Naomi Klein laments in her must-read New York Times op-ed.

Sadly, Klein misses two important points.

First, it’s not a question of if but when humanity will be compelled to use geoengineering, unless we change course on our climate policies (or lack thereof). Second, all of this calls for more research and a clear, comprehensive governance effort on the part of governments and serious scientists – not a ban of geoengineering that we cannot and will not adhere to. (See point number one.)

Saying that we ought not to tinker with the planet on a grand scale – by attempting to create an artificial sun shield, for example – won’t make it so. Humanity got into this mess thanks to what economists call the “free rider” effect. All seven billion of us are free riders on the planet, contributing to global warming in various ways but paying nothing toward the damage it causes. No wonder it’s so hard to pass a sensible cap or tax on carbon pollution. Who wants to pay for something that they’re used to doing for free – never mind that it comes at great cost to those around them?

It gets worse: Turns out the same economic forces pushing us to do too little on the pollution front are pushing us toward a quick, cheap fix – a plan B.

Enter the Strangelovian world of geoengineering – tinkering with the whole planet. It comes in two distinct flavors:

  • Sucking carbon out of the atmosphere;
  • Creating an artificial sun shield for the planet.

The first involves reversing some of the same processes that cause global warming in the first place. Instead of taking fossil fuels out of the ground and burning them, we would now take carbon dioxide out of the atmosphere and bury it under ground. That sounds expensive, and it is. Estimates range from $40 to $200 and more per ton of carbon dioxide – trillions of dollars to solve the problem.

That brings us to the second scary flavor — which David Keith, a leading thinker on geoengineering, calls “chemotherapy” for the planet. The direct price tag to create an artificial sun shield: pennies per ton of carbon dioxide. It’s the kind of intervention an island nation, or a billionaire greenfinger, could pay for.

You can see where economics enters the picture. The first form of geoengineering won’t happen unless we place a serious price on carbon pollution. The second may be too cheap to resist.

In a recent Foreign Policy essay, Harvard’s Martin Weitzman and I called the forces pushing us toward quick and dirty climate modification “free driving.” Crude attempts to, say, inject sulfur particles into the atmosphere to counter the carbon dioxide that’s already there would be so cheap it might as well be free. We are talking tens or hundreds of millions of dollars a year. That’s orders of magnitude cheaper than tackling the root cause of the problem.

Given the climate path we are on, it’s only a matter of time before this “free driver” effect takes hold. Imagine a country badly hit by adverse climate changes: India’s crops are wilting; China’s rivers are drying up. Millions of people are suffering. What government, under such circumstances, would not feel justified in taking drastic action, even in defiance of world opinion?

Once we reach that tipping point, there won’t be time to reverse warming by pursuing collective strategies to move the world onto a more sustainable growth path. Instead, speed will be of the essence, which will mean trying untested and largely hypothetical techniques like mimicking volcanoes and putting sulfur particles in the stratosphere to create an artificial shield from the sun.

That artificial sunscreen may well cool the earth. But what else might it do? Floods somewhere, droughts in other places, and a host of unknown and largely unknowable effects in between. That’s the scary prospect. And we’d be experimenting on a planetary scale, in warp speed.

That all leads to the second key point: we ought to do research in geoengineering, and do so guided by sensible governance principles adhered to be all. We cannot let research get ahead of public opinion and government oversight. The geoengineering governance initiative convened by the British Royal Society, the Academy of Sciences for the Developing World, and the Environmental Defense Fund is a necessary first step in the right direction.

Is there any hope in this doomsday scenario? Absolutely. Country after country is following the trend set by the European Union to institute a cap or price on carbon pollution. Australia, New Zealand, South Korea, and also California are already – or will soon be – limiting their carbon pollution. India has a dollar-a-ton coal tax. China is experimenting with seven regional cap-and-trade systems.

None of these is sufficient by itself. But let’s hope this trend expands –fast – to include the really big emitters like the whole of China and the U.S., Brazil, Indonesia, and others. Remember, the question is not if the “free driver” effect will kick in as the world warms. It’s when.

Posted in Economics, Geoengineering, Science / Tagged , | Read 1 Response

Antarctica’s Glacial Melt

There should no longer be any doubt. Climate change is here, and it is happening. 26,000 broken heat records this summer speak for themselves.

Extreme weather events hit home. Another consequence of climate change, by contrast – rising sea levels – often seems far away and far off.

“Far away” is easily dismissed. U.S. coasts are as much in danger as sea shores anywhere else on the planet.

“Far off” often seems tougher to address. After all, seas have only risen by inches so far. Projections say we could see three or more feet by the end of the century.

Even right now, though, we’re seeing the evidence of sea level rise. Antarctic ice sheets have been melting to the tune of 24 cubic miles of melt water per year, every year, since 2002.

That is a huge number, but a fairly abstract number. So The Globalist designed a quiz to make the giant quantity feel a bit more real. EDF was honored to help with the research for the quiz.

See if you can answer the question:

If you were to take the melt-off from Antarctica’s ice sheets over the past decade (2002 to 2012) and pour it into a California-sized Jell-O mold, how high would the water rise?

The right answer might surprise you. Hint: Think Paul Sturgess, the world’s tallest professional basketball player.

And check out The Globalist quiz for more details.

Posted in Arctic & Antarctic, Extreme Weather, News, Oceans, Science / Read 1 Response

Economists save the planet

Why are we so “gung-ho” about cap and trade? The term might be banned from Washington and much of our vocabulary at the moment, but it’s still far from a trick question.

Call them what you want, environmental markets are fundamentally the most scientifically sound, economically efficient, and often the only way forward.

No wonder countries the world over are adopting or planning to adopt them.

We are starting a new blog specifically focused on market forces and why re-guiding them is the only solution to many of our environmental problems.

Individual volunteerism won’t do. Blocking market forces won’t do. Subscribing to the new blog won’t make the world a better place all by itself either, but it probably doesn’t hurt.

Posted in Climate Change Legislation, Economics / Tagged | Comments are closed