Has crop ethanol met its Waterloo?

It should be obvious by now that I think today's is one of the best issues of Science in recent memory. This will be my last post out of this issue, but even these three posts don't come close to covering everything in there that I think is cool. If you don't work at an institution that has a subscription, you could do a lot worse for your brain than buying a copy online or at a newsstand or bookstore. So to wrap up my blogging on this one, I'll cover some papers that support my extreme distaste for biofuel mania, especially with respect to food crops such as corn and soybeans. A pair of articles today find that using food crops for ethanol is even worse in terms of carbon balance than continuing to use fossil fuels.

My regular readers will no doubt be aware that I positively loathe the idea of using corn for ethanol, and am somewhat dubious of the benefits of using even cellulosic ethanol as a biofuel. These are at best stopgaps on the way to fully clean energy sources, do not in general remove a great deal of carbon from the atmosphere, and may have significant adverse effects on the environment and carbon balance. So you should consider this post in light of the significant potential for confirmation bias. That said, these papers seemingly end the debate on the carbon balance benefits of corn or soybean ethanol, and raise serious questions about the benefit of any form of monoculture intended to replace petroleum, especially if they take over cropland or forest.

The fundamental problem with previous models of greenhouse gas reductions due to biofuels, according to the authors of these papers, is that they do not take into account the carbon debt incurred by altered land use. For instance, clearing land to allow the planting of biofuel monocultures has the effect of releasing all or almost all of the carbon presently fixed in plants in those areas (1). Moreover, forward-looking economic models were not previously employed to judge the likely effects of shifting food crops into fuel production. For instance, the increased cost of corn might induce clear-cutting intended to free up more cropland to grow the now more-profitable food crop (2).

What happens when you start taking those "carbon costs" into account? Searchinger et al. find that corn ethanol doubles greenhouse emissions versus petroleum over a period of 30 years and doesn't break even for 167 years. Fargione et al. predict that it takes 48-93 years, depending on what kind of source land is used, before corn ethanol pays back its carbon debt. And it's not even the worst: biodiesel derived from lands that used to be rainforest take more than 250 years to balance the carbon sheet, on average. Even cellulosic energy sources, if they are grown on viable cropland, produce more greenhouse gases over the next 30 years than petroleum does (2).

So, are we totally screwed? Not exactly. Both papers suggest that cellulosic sources grown on marginal croplands or prairie, or derived from existing biomass waste (i.e. inedible cornstalks) still end up on the right side of the carbon balance sheet. This is consistent with estimates from a study I discussed previously.

The ideal response to both global warming and oil dependence is to depress petroleum usage (by increasing fuel mileage and encouraging public transit) while transitioning to a completely green transportation system that doesn't rely on combustion at all. Stretching out oil and growing forests is the best option for slowing emissions short term, and does not require an additional construction of infrastructure to produce and distribute ethanol. If biofuels are unavoidable, however, then they should be derived from non-food crops grown on marginal land if at all possible.

It's still not clear that biofuels can replace petroleum, so they may not help us as much as we'd like. However, if they are not to hurt us, we must make sure that we make wise choices about what kinds of sources to use and where to grow them. The best evidence now conclusively indicates that ethanol from corn and soybeans (except for cellulosic derived from their spare biomass) is not the way.

1. Fargione, J., Hill, J., Tilman, D., Polasky, S., Hawthorne, P. (2008). Land Clearing and the Biofuel Carbon Debt. Science, 319(5867), 1235-1238. DOI: 10.1126/science.1152747

2. Searchinger, T., Heimlich, R., Houghton, R.A., Dong, F., Elobeid, A., Fabiosa, J., Tokgoz, S., Hayes, D., Yu, T. (2008). Use of U.S. Croplands for Biofuels Increases Greenhouse Gases Through Emissions from Land-Use Change. Science, 319(5867), 1238-1240. DOI: 10.1126/science.1151861

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Policy and the law of prudence

The one thing I find most infuriating in debates about anthropogenic warming is the inevitable point in the conversation when the denialist states that we shouldn't do anything because we aren't really sure that humans cause global warming. If you point out to him that the vast majority of scientists believe the evidence supports this conclusion, he will either point out that scientists 30 years ago were wrong about something relating to climate (the "global cooling" gambit), or that people have been wrong about things before ("everyone believed the earth was flat"). Both these points are irrelevant: forecasting technology has improved vastly, and it was not scientists who believed the earth was flat (most educated people knew it to be a sphere), but backwards hicks like himself. But there's a more important point to be made: when it comes to policy decisions, it doesn't matter whether we cause global warming or not.

In the first case, most of the things we need to do about climate change are just plain good ideas, whether the earth is warming or not. We need more efficient ways to grow and transport our food. We need to end our dependence on the finite resource of fossil fuels. We need to make our cities better filters of their own pollution. We need better water management. We need to end suburban sprawl. We need to control the global population of human beings. It doesn't matter whether our planet is warming, cooling, or staying the same: almost all mitigation policies make sense in any context. For policymakers to sit on their hands and ignore these steps is inexcusable, regardless of their belief in anthropogenic warming.

When it comes to emissions caps, however, the typical denialist will draw his line in the sand. Why ruin the economy if we aren't sure that warming is our fault? Leaving aside the fact that economic forecasts are at least as unreliable as climactic ones (and therefore just as bad a reason to make decisions), there is a very good reason to alter our policies to eliminate emissions of all kinds. This is the law of prudence: If you don't know how it works, don't mess with it, especially if you're stuck with it.

You don't try to jack around in the engine before you board your passenger flight to Miami. You don't screw with the wheels before you get into a roller coaster. Why not? Because you don't know how it works, and once you get on that thing you can't get off. The same principle applies here. We're stuck on this planet; we can't leave and start over. If we ruin it, we will all die. Thus, if you truly believe that our best scientists really don't know enough about this planet to say how its climate system works, then your only rational choice is to minimize our impact on that system.

Denialists love to argue that we're uncertain about climate change as if ignorance is a reason for inaction, but this does not follow. Inaction is a decision, and it is the wrong decision to make when faced with uncertainty. When ignorant of an essential system's mechanics, we do not want to damage it, and that means not screwing with it. The reduction of all forms of pollution (including carbon) as rapidly as possible is the best decision we can make if we're unsure of what's going on with our environment. If, as is the case, we suspect or believe that our actions are outright harmful, then elimination of emissions is the only reasonable option.

You'll hear the uncertainty argument again; in fact, you've probably already heard it once today if you've had a discussion about Gore's Nobel Prize or the environment generally. Uncertainty is always used as an justification for inaction, but it actually supports the opposite.

For Blog Action Day...

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The new Nobelity

I try not to pay too much attention to the Nobel Prizes, because the recipients are usually either boring, obvious choices or stupid ones. This time around, most fell into the former category. The choice of Capecchi, Evans, and Smithies for their development of the genomic knockout mouse was as unassailable as it was inevitable, and Fert and Grünberg's award for giant magnetoresistance shared both those properties. Gerhard Ertl's work, which probably sounds dull or obvious to the layman, is in fact of staggering significance, and his prize too was richly deserved, if not particularly exciting to read about. I can't recall ever having read anything by Doris Lessing, but this is true of most Nobel Literature Prize winners. I have always been confused by the idea of awarding a literary achievement prize to anyone who is still alive, anyway (more on that in another post, perhaps). Some have complained about her award, but the controversy on this prize is muted, especially compared to the storm that broke with today's announcement of the Nobel Peace Prize. No doubt you've heard that the prize was given to Al Gore, just days after a British judge debunked his film, which reflects poorly on our media. In fact, Gore was a co-recipient with the Intergovernmental Panel on Climate Change, and the judge, though he found that the film advocated a viewpoint and contained nine errors (most of them insignificant or understandable), did not dispute its central message. These facts are related, and understanding that relationship is, I think, essential.

The finding that An Inconvenient Truth advocates a viewpoint is unsurprising, because Al Gore is unapologetically an advocate for controlling anthropogenic warming. He is not a scientist, but a man who uses science (sometimes disputed science) to send a message. The Peace Prize has been awarded to advocates before, and justly so. Indeed, it would be completely unreasonable to award it to someone who was not some kind of advocate — gazing at your navel and saying "Apartheid is bad" does not qualify you for any kind of award, while getting thrown in prison for trying to end it arguably does.

On these grounds it would be inappropriate to give the Prize to the IPCC on its own. The IPCC is a scientific organization, and advocacy or even the appearance of advocacy would significantly undermine its mission. Gore and his allies make use of the IPCC's findings, and indeed without the weight of the IPCC consensus their fight against anthropogenic warming would go the same way as the awakening that followed the publication of Silent Spring. Gore is a strong, visible advocate, the sort of person or organization that deserves the prize, but though the IPCC did all the hard work, it is not an advocate, and would be practically invisible without the help of Gore and his friends. Without the scientists, the advocacy would be ignored, and without the advocates the scientists would be ignored. As such, if a Peace Prize is to be given for the fight against warming, both must be honored. That is what the committee did.

Was it justified to give a Peace Prize for this? At first blush, it might not seem that warming has all that much to do with peace. Of course this isn't particularly relevant — the Peace Prize has been awarded in the past for innovative banking approaches, service to the poor, and agricultural research. But if you want to be a stickler nonetheless, you should know that the effects of anthropogenic warming are likely to be a significant threat to security in this century, and perhaps the largest threat. If you think I'm not a credible witness on this point, perhaps you will listen to Gen. Gordon R. Sullivan, Adm. Frank Bowman, Lt. Gen. Lawrence P. Farrell Jr., V. Adm. Paul G. Gaffney II, Gen. Paul J. Kern, Adm. T. Joseph Lopez, Adm. Donald Pilling, Adm. Joseph W. Prueher, V. Adm. Richard H. Truly, Gen. Charles F. Wald, and Gen. Anthony C. Zinni. If you don't want to read their report detailing the security threat to the United States from warming, I'll give you the short version.

Climate change will cause agricultural disaster and population displacements in some of the most unstable places in this world. Rising sea levels will push millions of refugees out of Bangladesh. Changing rainfall/snowfall patterns will cause water shortages in Africa, Asia, and the Middle East, and these droughts will be accompanied by famine and disease. The cruel fact is that the countries hardest hit by global warming will probably be those least capable of mitigating its effects. The natural result of this tumult will be resource wars, including the possibility of wars involving nuclear powers such as India, Israel, Pakistan, Russia, and China. Famine, disease, and war will displace millions in these regions, leading to increased competition for resources in more habitable regions and an increasing strain of immigrants in nations where the effects of climate change have not been so dire.

In my own view, it is likely that societies facing this degree of resource scarcity will fracture along ethnic or tribal lines, leading to repeated incidents of genocide much like that we have seen in Darfur. Hopefully the situation will not advance to the point of nuclear war, but it is entirely possible that unhinged tribalists in unstable countries like Pakistan will decide that if they cannot have the resources, nobody can. Unchecked, global warming may well lead to war and an era of genocide unlike anything the world has yet known, including the unthinkable prospect of a second nuclear war. Only this time, the victim will be able to return fire in kind.

Was this the committee's justification? I couldn't tell you. It probably contributed, but it's equally fair to say that they were likely motivated by a political desire to tweak the Bush administration. It's fair to say that Bush deserved it, as his attitude towards the problem has been abominably stupid. More broadly, they may have meant the endorsement to help silence global warming deniers, though at this point the outright denial of warming is so far to the fringe that it will likely have no effect among stalwarts. At this point the essential debate concerns the policies that ought be adopted in light of the warming trend — in my view, the committee's action will add weight to the IPCC recommendations. The choice is still rightfully controversial, but it isn't outrageous or improper. They've made worse decisions.

The Gore-IPCC Peace Prize will be widely discussed for some time, and it is to be hoped that by awarding this prize the committee will encourage new efforts on greenhouse gas reduction and climate change mitigation. But the committee has tried to use the prize in such a way before, without success.

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A Program for Response to Climate Change

The recent news that polar bears might disappear by 2050 shouldn't really shock anyone, but it does serve as a reminder that the global warming policies being proposed by our political elites are failures-in-waiting. That the Republicans have presented a suite of jokes as policy proposals is par for the course, but the Democratic approaches are equally weak. Most of them advocate cuts in greenhouse gas emissions, but that ship has already left port -- no cuts made over the next 40 years can prevent global warming, they can merely limit it. That's still a noble goal, and carbon cuts should be made, but the belief that we can do something to stop warming and then all will be well is fundamentally misguided. What we need and deserve to see from our candidates is not just their promises to reduce emissions, but their plan for mitigating global warming's impact.

Climate change will alter the temperature schedule and rainfall levels in many agricultural regions, producing novel climates in some portions of the country. Water may become scarce in some areas of the country now thickly populated. Sea levels will probably rise, threatening coastal regions. As supplies are exhausted, petroleum prices will begin to increase, making the modern suburban lifestyle less tenable for the middle class, especially when those price increases percolate through every other sector of the economy.

The response has to be multifaceted and nimble -- years of effort have not yet yielded any certainty on the precise effects of warming on the environment. So it would be a mistake for anyone to plan on the basis of any particular model. However, there are general steps that could be taken for preparedness.

Agricultural research and readiness: The United States has a plethora of agricultural universities, and now is the time to strengthen their research programs, with the aim of producing hardier, more efficient strains of our workhorse foods. Make use of the powerful techniques developed in the study of human health and bend them to the study and improvement of plants. Technical development should also be a focus: particular attention should be paid to the devising of more efficient irrigation systems. Pest control and topsoil management should also be priorities. Existing technologies should be pushed into use wherever possible; agricultural schools should be used as distribution centers to help local farmers put novel techniques into use. The government should take an active role in helping farmers adapt to the changes in local climate. The Department of Agriculture, in conjunction with local agricultural universities, should help farmers change what they grow and when they grow it so as to maximize productivity. This will have to come at the expense of tradition, and I'll miss Chilton County peaches if they have to go, but it's better for the food supply and better for the farmers if they're growing crops suitable for the climate they're experiencing.

Alternative fuels: By which I do not mean biofuels. In fact, biofuel initiatives should be abandoned immediately, not only because cutting forest to make way for biofuel monocultures is harmful to the environment, but also because biofuels will not substantially help carbon balance or warming in the long term. The simple fact is that burning biofuels is still burning something, and the additional CO2 and NO2 released during their cultivation will seriously diminish their potential to affect global warming. A recent (non-research) article in Science (subscription required) points out that sequestration of carbon in forests is superior to the use of biofuels from the pure greenhouse-gas perspective. Moreover, using arable land for biofuel monocultures will be a losing proposition when climate change stresses the food supply. Food prices in the United States and Mexico have already suffered some disruption from the proposed use of ethanol; when food itself starts being difficult to come by, the growing of corn for fuel (or even animal feed) is likely to be untenable.

If biofuels are to be used, then it ought only be when they can be produced exclusively from the refuse of existing food crops (cellulosic ethanol from cornstalks, for instance). Barring this, the government should enforce increasingly stiff fuel-efficiency requirements while pushing forward on research into non-carbon fuel sources for transportation. Simultaneously, every effort should be made to reduce the amount of automotive traffic required in everyday life...

Re-urbanization: Cities are crowded, messy, polluted, and filled with crime, but suburbs sprawl, destroy forests, promote excessive use of automobiles, and spread vile environmental impacts over a large area. As forests are our best friends in the fight against warming, anything that destroys them must be anathema. However, there is no way that any mandate of the government could shove everyone back into the cities. Rather, the government must work diligently to support the cities in their efforts to call people back by reducing crime and producing more family-friendly spaces. At the same time, the cities themselves must be revamped so that they are more environmentally friendly. "Green" buildings must be economically encouraged or enforced by statute. Public transit must be made as attractive and efficient as possible. Suburban sprawl must be curtailed, by inviting the nation back into the cities if possible, by forbidding further development in wooded areas if necessary. Increased property taxes encourage living in small spaces while providing additional revenues to support urban redevelopment.

Water Policy: Water management beyond the local level has largely been ad hoc up to this point, but with increasing populations in some major urban areas stressing the water supply of multiple states or large regions, a comprehensive higher-level policy must be put in place. The government should provide assistance to those wishing to move away from areas experiencing significant strains on the water supply, and help develop economic opportunities in areas where water is plentiful in order to make such moves desirable.

Disaster preparedness: One likely consequence of the development of novel climates is the destruction of the previous climates. In cases where temperatures rise and rainfall decreases, this will probably take the form of extensive forest fires. Even now it seems like every year brings a record number, and it's probably not because so many kids are playing with matches these days. The government will need to come up with a comprehensive plan for dealing with these fires without completely exhausting the men and women who fight them on our behalf. Trying to imagine and then plan for every possible contingency is a good way to get completely lost in details, but nothing DHS and FEMA have done since the Katrina disaster suggests that they have grown more nimble or capable. These agencies should be shaken up from top to bottom, and if necessary FEMA should be removed from the bloated and apparently completely ineffectual DHS.

This isn't everything that such a plan needs by half, and by this time next week I may have 3-4 more headings of components that are necessary. But it's telling that even the most environmentally conscious candidates seem to have only thought of one.

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