Volume 1, Number 30
9 December 2001

Global Warming

Dear Friends,

Of all the topics in The Quaker Economist, global warming has confounded me most. The subject is so technical (and I am not a techie) and the experts disagree, so that I feel like the selection committee for the Little Minister in J.M. Barrie's book of the same name. One member was so impressed by whoever was called for a visiting sermon that he voted for the one selected only because he was the latest to speak. I find myself agreeing with whoever last argued global warming, pro or con.

I believe that in a subject as important as this one, a scientist should be able to explain his or her position to a lay audience in nontechnical terms. I have been reading all the scientific articles I could find and understand; most I could not find or understand. I have consulted as many scientists as I could. I had luncheon with Kevin Tremberth, one of the top scientists at the National Center for Atmospheric Research (NCAR, fortunately located in Boulder), and have spoken at length with Jack Herring of Boulder Meeting, another NCAR scientist, and Roger Conant, a scientist member of my board. Both helped me immensely with this Letter, but I am solely responsible for it.

From all of that, here is what I think.

  1. The earth is warming, but how much is anthropogenic (caused by human activity) and how much is natural cycle I do not know. Neither do the scientists.
  2. Most of the evidence of anthropogenic warming resides in mathematical models. As an economist, I am familiar with mathematical models, and I know how wrong they can be.
  3. Scientists have measured warming at different times, at different parts of the earth, at different heights above the surface, and at different depths of the ocean. The measurements do not all agree.
  4. Those scientists who argue that global warming will be small say that the models used to prove its occurrence were fine-tuned: if they did not come out the way the model-maker expected, some of the inputs would be adjusted to conform
  5. The majority of scientists around the world, including many at NCAR, believe anthropogenic warming is a principal force.
  6. I never accept a position just because the majority believes it. (At one time the majority of scientists thought the sun revolved around the earth.)
  7. The media have given much more exposure to scientists who tout anthropogenic warming than to those not believing in it. Why? I think because it makes better copy.
  8. I'm strongly influenced by Walter Roberts (died 1990), founder of NCAR and a personal friend, who told me that global warming is occurring and we cannot stop it. We should be more concerned about what to do about it than to avert it, he said.

Richard Lindzen, the Alfred Sloan Professor of Meteorology at MIT and the principal proponent that global warming will be small, is a friend of a friend of mine. He reports (through my friend) that his principal evidence is that the temperature in the stratosphere has not changed. While scientists who emphasize anthropogenic warming say it is caused by increased carbon dioxide (the principal greenhouse gas outside of water), Lindzen argues that the increased warming causes ocean evaporation, and the eventual effect of the increased water vapor is a cooling that offsets the warming. He has switched positions on this, and then switched back again, each time with new evidence.

Lindzen, a member of the Inter-Governmental Panel on Climate Change, wrote the following about press reports (Wall Street Journal, 6/1/01):

"Last week the National Academy of Sciences released a report on climate change, prepared in response to a request from the White House, that was depicted in the press as an implicit endorsement of the Kyoto Protocol. CNN's Michelle Mitchell was typical of the coverage when she declared that the report represented 'a unanimous decision that global warming is real, is getting worse, and is due to man. There is no wiggle room.' As one of 11 scientists who prepared the report, I can state that this is simply untrue ...

"Our primary conclusion was that despite some knowledge and agreement, the science is by no means settled. We are quite confident (1) that global mean temperature is about 0.5 degrees Celsius higher than it was a century ago; (2) that atmospheric levels of carbon dioxide have risen over the past two centuries; and (3) that carbon dioxide is a greenhouse gas whose increase is likely to warm the earth (one of many, the most important being water vapor and clouds). One reason for uncertainty is that, as the report states, the climate is always changing; change is the norm. Two centuries ago, much of the Northern Hemisphere was emerging from a little ice age. A millennium ago, during the Middle Ages, the same region was in a warm period. Thirty years ago, we were concerned with global cooling. Distinguishing the small recent changes in global mean temperature from the natural variability, which is unknown, is not a trivial task ...

"We simply do not know what relation, if any, exists between global climate changes and water vapor, clouds, storms, hurricanes, and other factors, including regional climate changes, which are generally much larger than global changes and not correlated with them. Nor do we know how to predict changes in greenhouse gases. This is because we cannot forecast economic and technological change over the next century, and also because there are many man-made substances whose properties and levels are not well known, but which could be comparable in importance to carbon dioxide. What we do know is that a doubling of carbon dioxide by itself would produce only a modest temperature increase of one degree Celsius. Larger projected increases depend on 'amplification' of the carbon dioxide by more important, but poorly modeled, greenhouse gases, clouds and water vapor.

"My own view, consistent with the panel's work, is that the Kyoto Protocol would not result in a substantial reduction in global warming. Given the difficulties in significantly limiting levels of atmospheric carbon dioxide, a more effective policy might well focus on other greenhouse substances whose potential for reducing global warming in a short time may be greater."

Lindzen is but one of many scientists who have criticized the mathematical models. In "The Human Impact on Climate," Scientific American, 281(6):100-5, Karl and Tremberth open with "How much of a disruption do we cause? The much-awaited answer could be ours by 2050, but only if nations of the world commit to long-term climate monitoring now."

As Lindzen says, all scientists agree that the earth has gone through natural warming and cooling cycles. Kevin Keigwin, an oceanographer at Woods Hole (MA) observatory, prepared a 3,000 year record of the temperatures of the Sargasso Sea "through analyzing thermally dependent oxygen isotopes in fossils on the ocean floor. He discovered that temperatures a thousand years ago ... were two degrees Celsius warmer than today's. Roughly confirming this result are historical records — the verdancy of Greenland at the time of the Vikings, . . ." (from The American Spectator, May 2001). During the last few centuries preceding the birth of Christ annual temperatures began to decline. The two succeeding millennia in the AD period have seen temperatures substantially lower than the two preceding millennia, again with considerable variation. During this latter period the decline bottomed out roughly between AD 500 and 700. They then rose again reaching a high between 900 and 1200 AD. At the end of the 14th Century temperatures again began to decline. By the beginning of the 16th Century this change started to be noted in writings of the time. The period of this "Little Ice Age" lasted well into the 18th Century. By the 19th Century, things started to warm again, and have been doing so ever since, with considerable short term variation, of course, but have never approached the temperatures prevalent in ancient times The causes of these changes have nothing to do with the burning of fossil fuels. (This information was compiled by my brother-in-law, Tom Todd.)

The Harvard-Smithsonian Center for Astrophysics has asserted that the increase in greenhouse gases has been spread over the last century and most of the small earth temperature rises since 1880 occurred before gases from human activity were being emitted. "The eco-system itself dwarfs human activity in generating or absorbing carbon dioxide." The eleven-year sunspot cycle has been blamed by some scientists. Sallie Balliunas, an astrophysicist with the Harvard-Smithsonian Center, and her co-workers studied records of the past 120 years and found the Sun responsible for much of the Earth's temperature shifts. Charles Harper, planetary scientist at Harvard, criticized the inter-governmental report for being based more on deficient computer models than on ground-based temperatures during the period in which greenhouse gases were mainly omitted. (Quoted from my book, The Moral Economy, p. 63.)

In The Skeptical Environmentalist (see TQE #29), Bjorn Lomborg reports that "a recent Atmosphere-Ocean General Circulation Model showed that the increase in direct solar irradiation over the past 30 years is responsible for about 40 percent of the observed global warming" (p. 276), but he also notes that "the connection between temperature and the sunspot cycle seems to have deteriorated during the last 10-30 years ... Most likely, we are instead seeing an increasing signal, probably from greenhouse gases like CO2. Such a find exactly underscores that neither solar variation nor greenhouse gases can alone explain the entire temperature record" (p. 278).

Also, in "Climate Forcing by Changing Solar Radiation" (Journal of Climate, 11, 1998, p.3069), Lean & Rind show that while "solar radiation changes may have been the predominant climate forcing during the seventeenth and eighteenth centuries, ... according to simple linear parameterization of surface temperature anomalies and solar irradiance based on this preindustrial relationship, less than one third of the earth's's surface warming since 1970 is attributable to changes in solar radiation.''

In "The Coming Climate," (Scientific American, May, 1997), Karl, Nevills, & Gregory spend many pages on the inadequacies of mathematical models predicting that climate change is caused by global emissions of greenhouse gases, aerosols, and other relevant agents. Yet they conclude that these must be watched as probable causes.

In his book, The Skeptical Enviromentalist (see TQE #29), Bjorn Lomborg writes (p. 317): "Temperatures have increased over 0.6C over the past century, and it is unlikely that this is not in part due to an anthropogenic greenhouse effect, although the impression of a dramatic divergence from previous centuries is surely misleading." He argues that fighting the warming earth would be enormously expensive, and we would better spend those trillions of dollars in adjusting to the change, as generations in the past have always had to do, but in a less technological world.

The chief difference between scientists and economists seems to be that scientists do not calculate the costs of whatever action they propose, while economists (like me) often do not understand the science. So, where does this leave us?

We must indeed be concerned about anthropogenic global warming, but we should calculate the costs and benefits of trying to stop it and compare them with the costs and benefits of not doing so. A benefit of trying to stop it would be, "if we are totally successful the climate will warm only to the extent that nature determines." The cost of doing that would be "what all the people of the earth must suffer to make it happen." That could include a much lesser life style than we are accustomed, as well as slowing the growth of the poorest of the world. There are also costs and benefits of not stopping the global warming, which I leave to your imagination.

In each calculation, we must take account of the probability that whatever we propose or think would indeed occur. (We should not pay a high cost to prevent something that is very unlikely, say billions of dollars to ward off a meteor.)

We should also consider the costs versus benefits of doing it part way. While most governments have agreed to the Kyoto protocol (except the United States), they have not put it into effect, and I am dubious that anyone will. A benefit would not be that it would stop global warming, but that it would delay it by a short period (some scientists say no more than seven years). We may also consider that the costs would be so high that, for political reasons, they would never realistically be paid. Should we devote our efforts to fighting this recalcitrance, or to adapting to the circumstance, or part one and part the other? I do not have the answer, only the question. Unfortunately, not enough of us have been asking the question.

How would we adjust? I do not trust the government to take the initiative. Any government or inter-governmental body, with its defense of power bases, its "all-must-be-alike" thinking, its attempt to please everybody (or at least the majority of voters, who also don't count costs), and with its bureaucratic squabbles, would never be able to coordinate the effort of adjustment.

Instead, millions upon millions of individuals would do the adjusting, calculating their own private costs and benefits. Some would insulate their houses, some would sell their farms and move father north; some would inoculate against new diseases; some would give up farming and take other jobs, some would install air conditioning, some would irrigate, some would move farther from the seashore. And so on. Fortunately, the warming will be so gradual that each generation would bear only a small part of the long-run cost.

On a few points we should all be agreed. Global warming or no, we should decrease automobile and factory emissions, fouling of rivers, and other kinds of pollution. The benefit might not be to stop global warming but merely to make our Earth a more pleasant place to live. How much cost are we willing to pay for that? What do you think?

In Peace, from your friend,

Jack Powelson

Readers' Comments:

Please send comments on this or any TQE, at any time. Selected comments will be appended to the appropriate letter as they are received. Please indicate in the subject line the number of the Letter to which you refer! The email address is tqe-comment followed by @quaker.org. All published letters will be edited for spelling, grammar, clarity, and brevity. Please mention your home meeting, church, synagogue (or ...), and where you live.

Why do people in the present era in the US almost instinctively side with the pessimists, the panic-button-pushers? Why do advocates arise on the side that tends to increase costs rather than on the side that tends to compare costs and benefits? There have been a few books lately about public perceptions of risk as opposed to statistical probabilities, and these may offer clues. It might also be a matter of where confidence and trust are placed, but this would have deeper roots. Possibly stuff for contemplation in a future Letter.

— J.D. von Pischke, a Friend from Reston (VA).

Apparently, Mars may be warming, too. It is unlikely that the change in Mars' climate is entirely due to the presence of human probes in that region of space. Here is a quotation from the report, from the New York Times, 12/7/01.

Photographs of the south polar ice cap of Mars, taken by a spacecraft in 1999 and again this year, have revealed a marked erosion of the year-round reservoir of solid carbon dioxide there, scientists reported in an article being published today in the journal Science.

— Gusten Lutter, Mountain view Meeting, Denver (CO).

Jack's letter credits Lomborg's analysis of the high cost of trying to stop global warming. Lomborg, in turn, quotes Nordhaus extensively on the high costs of mitigation policies. Nordhaus has been criticized for ignoring the economic gains from new technologies which would replace carbon based generation of power. For example, Nordhaus's 1990 analysis estimates a cost of $200 billion/year. Von Weizsacker and Lovin (Factor Four, 1997, p. 150) argue the magnitude of this number is about right, but the sign is wrong, if one brings into the calculation conservation, efficiencies and new technologies, which Nordhaus neglected. There is a report from the World Resource Institute by Repetto and Austin (The Cost of Climate Protection: A guide for the perplexed, 1997) which points out how drastically economic models of the cost of climate protection depend on such often hidden assumptions. One conclusion of theirs: "Under the best-case assumptions, a reduction in CO2 emission by 2020 would result in a substantial improvement in GDP relative to its business-as-usual path".

— Jack Herring, Boulder (CO) Meeting of Friends

When it comes to taking care of our bodies, we don't simply wait for absolute proof or insist on absolute perfection. Nor do we set our health targets based on simple cost benefit analysis. We pragmatically accumulate a regime of practices that contribute to the longevity and happiness of our lives. Of course, we are careful not to accumulate bad habits also. This is in some way a pragmatic expression of thankfulness to God for our bodies. We would do well to apply the same thankfulness and pragmatisim to our care of the planet as well.

— Patrick Koppula, Golden Gate Lutheran Church, San Francisco (CA)

"Fortunately, the warming will be so gradual that each generation would bear only a small part of the long-run cost."

Not necessarily true. If (or when, if warming continues) the Antarctic ice cap falls into the sea, that generation will pay heavily. Coastal areas under water and untold millions drowned would be only the immediate effects.

— Jim Caughran, Toronto (Ontario) Monthly Meeting

I think your paragraph starting, "How would we adjust?" is vulnerable. To the extent that the optimal measures are ones that people have incentives to take, of course there is no problem. But to the extent that the optimal measures are ones for which there is no incentive in ordinary market conditions, e.g., to cut back on activities that generate greenhouse emissions, your apparent approach will lead to underuse of those measures. Of course one can argue that the bureaucracy, etc., associated with creating incentives of this sort will be costly and itself generate errors, but it isn't clear that — if anthropogenic global warming is serious — avoidance of those errors justifies foregoing the potential advantages.

— Steve Williams, Bethesda (MD) Meeting

My rather simplistic view has long been that, even if the chances of significant human-made effect are small, the costs of global warming, even though spread over a century and more, would be sufficiently high to warrant doing what we reasonably can to reduce that effect, especially considering there are other probable benefits to "doing what we reasonably can," e.g., more efficient use of hydrocarbons for fuel, e.g., driving an SUV a mile or more to buy a quart of milk.

— Don Marsh, Seattle (WA).

Your thoughtful letters are, as usual, thought-provoking and a joy to receive.

— Tom Selldorff, Weston (MA).

You are right to be suspicious, or at least wary, of computer models, but computer models are all we have to go on. The only alternative is just intuition, for example unscientific generalizations from facts such as that the last few years have been the hottest in the last millenium. Yes, computer models can be wrong, but they can be right too, and if you believe in the process of science in which good science expels bad science (under peer review, testing, etc) then there is reason to believe that the models of climate change are evolving to become more and more accurate. There is no alternative to computer models, is there?

— Roger Conant, Mt. Toby (MA) Meeting.

If the consensus of scientists is wrong and Lomborg and Lindzen are right, those who were led to act according to their best light would have made a few unnecessary choices, such as living close enough to work and shopping to forego the use of a car, rather than driving many, many hours each week. They may waste time evaluating what is important to them as humans, as children of God.

If the opposite is true, if the overwhelming majority of the knowledgeable people are correct, then people my age and younger may see perhaps a quarter, perhaps half or more, of Earth's species extinct or doomed to extinction in our lifetime, a paucity of biodiversity likely to exist for the remainder of the lifetime of our species.

Karen has posted her complete reply to TQE #29 at http://www.quaker.org/fep/CLQ29rep.html

— Karen Street, Berkeley (CA) Meeting.

There is an unusual high consensus among climate scientists that global warming is underway and irreversible. The debate concerns how to reduce and hopefully reverse the rate of increase.

As a new TQE reader very interested in Jack Powelson's list of topics, I must say I hope he is not generally subject to the force field of the White House–Wall Street Journal spin, as he does seem to be on global warming. Jack, there are excellent readable and very clear presentations in a recent series in New Yorker and Granta magazines. Not only are world scientists in agreement, but those level-headed Dutchmen are in the process of spending several hundred million dollars to help citizens of their lowlands survive the first floods. I hope you will review some of this material and revise your letter on global warming.

A Friend in concern about the life span of humanity on Earth,

— Merlin Taber, member of Champaign-Urbana Illinois Monthly Meeting [letter dated 7 May 2005]


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Publisher: Russ Nelson, St. Lawrence Valley (NY) Friends Meeting

Editorial Board

  • Roger Conant, Mount Toby Meeting, Northampton, MA.
  • Amy Cooper, Cambridge (MA) Friends Meeting (but living in Lafayette CA).
  • Ann Dixon, Boulder (CO) Meeting of Friends.
  • Virginia Flagg, San Diego (CA) Friends Meeting.
  • Merlyn Holmes, Unitarian, Boulder, Colorado.
  • Janet Minshall, Anneewakee Creek Friends Worship Group, Douglasvillle (GA).
  • Jack Powelson, Boulder (CO) Meeting of Friends, Principal Editor.
  • J.D. von Pischke, a Friend from Reston, VA.
  • Geoffrey Williams, Attender at New York Fifteenth Street Meeting.

Members of the Editorial Board receive Letters several days in advance for their criticisms, but they do not necessarily endorse the contents of any of them.

This newsletter was formerly known as The Classic Liberal Quaker.

Copyright © 2001 by John P. Powelson. All rights reserved. Permission is hereby granted for non-commercial reproduction.

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