Creative Solutions to the Problem of CO2?

Chapter 4F

Creative Solutions to the Problem of CO₂?

Those scientists who foresee a catastrophe vehemently disapprove of a wait-and-see attitude. By the time we have conclusive proof, they say, it may be too late. They want to curtail CO₂ emissions now. From a professional philosophical perspective, it appears at first sight that they are right: Under conditions of uncertainty it seems reasonable to move so as to avoid disaster.

First sight, however, might be as misleading in social policy as in love. Dissenters argue that the present conditions of uncertainty do not justify the drastic controls pessimist activists hunger for. They suggest two reasons why.

The first reason is that there may be alternative solutions even if the problem is truly serious. That is, we may be able to avert most, if not all, of the catastrophic scenarios without hindering the world’s industry in a massive scale. They do not have in mind the radical technological alternatives discussed in Chapter 2, e.g., solar power satellites and non-imaging optics, but rather ways of preventing the warming of the atmosphere even if fossil fuels continue to supply the lion’s share of our industrial energy.

Instead of our spending 250 billion dollars a year to reduce CO₂ emissions by 15%, as recommended by environmentalists (in the sort of rough financial estimate that can easily be off by a factor of two, most likely upward), a National Academy of Sciences panel (1992) suggested that we find means to compensate for any undue increase in greenhouse gases. The physicist Gregory Benford has cataloged several such means and has devised more of his own. One simple way to remove a large portion of the increase in CO₂ is to plant more trees. A campaign of reforestation in unused lands can be done for a few billion dollars, enhancing the quality of life, and giving us some breathing room in which to think of longer-term solutions.[1]

Plankton can provide another solution, since they can withdraw a considerable amount of fossil-fuel emissions as well. It is known that plankton are scarce in the polar oceans, in spite of the presence of large reserves of the nitrates and phosphates that plankton normally use. The reason seems to be the absence of iron in those oceans. But surely, John Martin suggests, we could ferry the needed iron dust for a relatively low price. According to Benford, for about ten billion dollars a year we could farm enough plankton to absorb as much as a third of a year’s fossil-fuel emissions.[2] This result is clearly superior to the 15% reduction that the draconian measures of the environmentalists would achieve for the sum of 250 billion!

Not surprisingly, such proposals would not be to the liking of environmentalists such as Bill McKibben, who believe that the only way to slow climate change is to use fewer fossil fuels.[3] The evidence seems to favor Martin’s idea, however. In a week-long experiment off the Galapagos Islands in 1996, 990 lbs. of iron made the waters bloom with plankton, Benford reports, which then covered 200 square miles, suddenly green.[4] This was just one of many successful experiments that have been carried out from 1993 to 2002. Some oceanographers worry that long-scale fertilization over a period of many decades may adversely affect the ocean;[5] but, as we will see below, this proposal has been offered only as a temporary measure.

Other possible solutions involve changing the albedo of the planet: If it reflects more sunlight, it will absorb less energy, and therefore the greenhouse effect will diminish, other things being equal. We might achieve this goal by increasing sulfur emissions in the South Pacific (which would increase cloud cover over the middle of the Pacific Ocean, the darkest and most solar-energy-absorbing area of the world). Or we might, alternatively, make jetliners burn a richer fuel mixture, which would leave a trace of fog high in the atmosphere. According to Benford, this process would offset a year’s worth of U.S. emissions for a mere $10 million!

Readers may worry about the possibility of hidden long-term environmental costs and dangers of such geo-engineering – ideological critics will be certain to do so. But all these suggestions are put forth as reversible experiments. In the case of the iron dumping, for example, if the iron dust is not continuously supplied, the polar ocean will return to its previous state in ten days or so.

The greenhouse problem is thus not a case of having to act in the face of uncertainty so as to avert disaster. For given the possibility of apparently reasonable, and significantly cheaper temporary solutions, the wise course of action is to reduce the uncertainty before imposing drastic permanent solutions. That is, we ought to increase our knowledge of the factors that may influence the warming of the atmosphere, and particularly of the ways they affect each other. We should, thus, attempt to gain a better global understanding of the Earth’s environment. Only then will our worries command the universal respect now demanded by the pessimists.

This result is strengthened by the realization that we know very little about how the global and regional environments interact. This is the second reason adduced by the dissenters. To see what they mean, think about how irrigation and other uses of land affect the local climate. Overgrazing in Northern Mexico makes for temperatures as much as four degrees Celsius hotter than you find in Arizona, just a few dozen meters away. On the other hand, irrigation in the plains of Colorado, where corn and other crops have replaced dry prairie, has reduced the mean temperature in July by two degrees Celsius. Transpiration by plants seems to cool the air and produce clouds over the plains. Further irrigation, then, may enhance the effect, for the plains’ winds will cool the nearby mountains, and that will increase rainfall there.[6] Some may wish to draw the conclusion that the global problem of climatic change will thus resolve itself into a collection of regional problems. It seems to me, however, that the wisest approach is to determine how regional climates interact with the global climate. Just to parade a trivial example: We would not want to increase irrigation in dry Southern California in a year when a strong El Niño is bound to dump near-disastrous amounts of rain on the region.

We may not wish to postpone action until the pessimists’ computer models place the catastrophe beyond doubt. We may find a reasonable compromise by searching for a better global understanding of our planet (and of the problem of CO₂ in that context).[7] Even if the dissenters are right and global warming turns out to be a false alarm, sleeping free of worry will not be the only benefit to derive from that search. Our new views will improve our dealing with the Earth in a myriad of ways.

Eventually the story will likely be resolved by space technology used in combination with fields like oceanography and paleobiology. The idea behind the “Mission to Earth,” for example, was precisely to look at Earth from space the way we have looked at other planets. This most ambitious mission evolved into the somewhat more modest Earth Observing System, a multi-billion dollar, interdisciplinary effort to understand global climate by observing the Earth from space. The three main instrument platforms are called Terra, Aqua and Aura (to study, respectively, land, water, and atmosphere). It is clear to many scientists that even this effort must be surpassed. A recent meeting of the National Research Council attempted “to do for climate change what has been done for astronomy, planetary science, and solar physics: create consensus on a realistic, long-term blueprint for the field, including the most important questions to be answered and the tools needed to explore them.”[8]

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[1]. According to Benford, it would take a land the size of Australia covered with trees to soak up all the present increase in CO_2. “Climate Controls,” Reason, Vol. 29, No. 6, November 1997, pp. 24-31.

[2]. Ibid., p. 27.

[3]. William McKibben, The End of Nature,

[4]. op. cit.

[5] P.G. Falkowski, Scientific American, op. cit., p. 61.

[6]. Jennifer Couzin, “Landscape Changes Make Regional Climate Run Hot and Cold,” Science, Vol. 283, 15 January 1999, pp. 317-319.

[7]. This will, of course, make for improved climatic computer models.

[8] Andrew Lawler, “Stormy Forecast for Climate Science,” Science, Vol. 305, August 20, p. 1094. Unfortunately, I fear, the needed effort may be undermined by the political advocacy by scientists during the past several years. According to this article, “Whereas fiscal conservatives would attack any massive new research program as unaffordable, liberals are likely to see it as a ruse to delay action on the underlying problems that are causing global warming.” P. 1097.