In all of this work, my goal was to do an objective scientific analysis and new research, following traditional scientific principles of disprovability. This research includes observations (empirical studies) and theory. Wherever possible, theoretical models have been tested and validated.

Now that global warming has become a major public issue, a great many people are speaking and writing about global warming , regardless of their knowledge, experience, research, and study of the subject. As a result, people have been asking me a variety of questions about the scientific basis of what we are being told.

Ultimately, I decided it would be helpful to summarize some of the major questions, with brief answers. To assure the reader that I have done years of research on this subject, I have also listed my major papers that deal directly with ecological effects of global warming or provide some scientific results essential to assessing some of its possible ecological effects. That list follows the 21 questions and answers.

One of the reasons that debates over global warming become confused is that the subject raises a number of scientific questions and as a result people often talk at cross-purposes. Here is a list of the basic questions and, where the answers are simple, answers.

Questions about Global Warming Itself

1. Is there a greenhouse effect?
Yes, some gases and liquids transmit visible light and absorb infrared light.

2. What are the major greenhouse gases in our atmosphere?
Water vapor, carbon dioxide, methane, nitrogen oxides, and CFCs (Freon). Strictly speaking, water vapor is the major greenhouse gas by concentration; the rest are minor constituents of the atmosphere.

3. If carbon dioxide is only 0.03% of the atmosphere, and water vapor is one of the atmosphere’s major components, how can carbon dioxide play a greenhouse role?
The answer has to do with the infrared wavelengths carbon dioxide absorbs uniquely and the fact that it liquefies and freezes at a lower temperature than water does and therefore can act as a greenhouse gas much higher in the atmosphere than water can.

4. Has the climate changed in the past prior to the industrial age and prior to any human effects on the atmosphere? If so, at rates and degrees that are forecast by current climate models to happen in the near future for us?
Yes, recent scientific evidence indicates that climate has always been changing, and prior to human influences, temperature has changed as rapidly and to as great a degree as is forecast to occur in the future from the global warming computer models.

5. Is carbon dioxide increasing?
Yes. There are solid data for this.

6. Are any of the other greenhouse gases increasing?
Data support that this is happening for methane, nitrogen oxides, and CFCs. It is worth noting that rate of increase in methane, CFC-11, and CFC-12 slowed (or even decreased) recently, for reasons that are not well explained or understood.

7. Has the temperature been rising steadily in recent years?
There have been decades in the 20th century when the temperature rose and decades when it fell. Up through the end of the 1990s, there had been a recent warming trend. So far, it is unclear whether this is continuing in the 21st century. A warming trend began around 1850, lasting until the1940s, when temperatures began to cool again, followed by a leveling off of temperature in the 1950s, and a further drop during the 1960s. After that, the average surface temperature rose.

8. What is the source of the major beliefs that global warming will occur and will have severe and undesirable effects?
Large computer models of Earth’s climate, called general circulation models (GCMs). There are at least 30 of these in use worldwide.

9. Have these climate models been proved to be true?
Scientists refer to such proof as model validation. The GCMs have not been validated with standard scientific methods.

10. Are there any legitimate questions about the forecasts from these climate models?
Yes. In particular: Climate modelers and their critics agree that the models do not do a very good job with water in the atmosphere. As the climate warms, more water is evaporated from Earth’s surface. A key question is: Does most of this water remain vapor (a greenhouse gas) or condense into clouds (that cool the climate)?

1. The models are steady-state, requiring and assuming that a specific change in the concentration of a greenhouse gas always has the same effect, regardless of past changes and total concentration. In fact, however, climate is always changing and is not in a steady state.
2. The effect on climate of carbon dioxide and other greenhouse gases is not linear. As the concentration of carbon dioxide goes up, an increase in a ton of CO2 has less and less effect on climate.
3. The relative effects of greenhouse gases compared to other factors that influence the Earth’s temperature are still open to debate. Among these other factors are the following:
   1. variations in the sun’s energy output;
   2. internal dynamics of the atmosphere, ocean, and life, which can modulate the direct greenhouse effects.
4. One of the main causes of variation in sunlight reaching the Earth is long-term variations in our planet’s path around the sun and its tilt and wobble as it spins like a top. Known as the Milankovitch cycles, these produce variations over 20,000, 40,000, and 100,000 years and are believed to be the primary drivers of the glacial and interglacial cycles.
5. The models are weak in their handling of the dynamics of land vegetation and ocean dynamics, and the coupling among these and the dynamics of the atmosphere. Since both oceans and land vegetation — especially forests, wetlands, and grasslands — can have major effects on atmospheric chemistry and physics, these aspects of the global models need considerable attention.

Questions about Possible Effects of Global Warming

11. The UN IPCC report states that up to 30% of animal and plant species will be threatened with extinction in the next few decades from global warming. Is this realistic?
In the past 2½ million years, under climate change as great and as fast, very few animal and plant species went extinct, far less than 30%. Most forecasting methods suggest that extinctions will be fewer than the IPCC asserts. Methods that suggest high rates of extinction assume that the world is in steady state and must be in steady state for species to persist; that species have little or no ability to adjust and adapt to climate change, contrary to well-established biological and ecological knowledge.

12. Will tropical epidemic diseases spread widely and rapidly?
Some excellent scientific papers show that temperature is not a good basis to forecast the spread of malaria and encephalitis. In fact, until the second half of the 20th century, malaria was endemic and widespread in many temperate regions and there were epidemics north to the Arctic Circle.

13. Will all the ice in the arctic melt?
Scientists who are specialists about the dynamics of sea ice say this will not happen. What might happen is that the Northwest Passage could open up – could become ice-free – for a few months in the summer; large areas of sea ice in the arctic might melt back, but these would be renewed each year. Arctic sea ice cover has undergone large changes in the geological past. For example, studies of deposits of fossil plankton indicate that sea ice in the Chukchi Sea was significantly less between 6,000 and 2,500 years ago. (These organisms respond rapidly to climate change.)

14. Will many arctic mammals go extinct from this change in ice cover?
Today’s arctic mammals evolved long enough ago for the species to have experienced past climate changes of equal rate and amount, and survived these. Experts on arctic mammals are concerned about a few that have very specific requirements and narrow, highly specialized ecological niches.

15. What about polar bears?
There are between 17,000 and 27,000 polar bears worldwide, and some of the populations have increased recently. Polar bears evolved several hundred thousand years ago and survived past climate changes equal in rate and amount to what is forecast to happen in the future. Ecologists and geneticists have in the past said that a species is not likely to be threatened with extinction until its number gets below 500 individuals.

16. Are all mountain glaciers melting because of present warming?
No. A prime example is Mt. Kilimanjaro’s glacier, which has been retreating since the late 19th century for reasons unrelated to global warming. Some mountain glaciers may retreat from global warming, but this can happen only when the temperature at the elevation of the glaciers is above freezing, or if global warming greatly reduces snowfall in those mountains.

17. Is Greenland’s ice melting? If so, will it disappear?
Current scientific papers disagree about the extent to which Greenland has lost its glacial ice in recent years and about how much the glaciers will change in the future. But the most thorough recent study by Greenland scientists suggests that Greenland’s glaciers have oscillated and are not in general decreasing.

18. Is the sea level rising rapidly because of global warming?
The sea level has been rising at about a 18 cm (7 inches) a century since the end of the last ice age. Between 1993 and 2003, the sea level rose about 3.1mm/year, or a rate of 31 cm (about 1 foot) a century. There is much disagreement about what may happen to the sea level in the future, even among climatologists and oceanographers, and even if global warming happens as forecast by the global climate models.

19. Will some island nations disappear due to sea-level rise?
Yes, even from the background rate (the rate at which the sea level has been rising without global warming). But the jury is still out as to whether the sea level is rising more rapidly than that, and therefore might be causing accelerated problems of this kind. (Of course, healthy coral reefs grow and in the past have kept pace with sea level rise.)

20. Will global warming affect world food production?
If global warming occurs, it will change where the best areas for agriculture will be. Present forecasting methods are not good enough to tell us much more than that. The result will be that some countries will benefit and others will lose agriculture production.

21. Are there any fundamental underlying issues we have not addressed?
One of the most important is whether, globally, life and its life-supporting systems have been, must be, and are best in a steady state, one that is unchanging over time. The most extreme concerns about global warming assume that life and its environment must remain as they were around 1960. This assumption is common among climatologists who argue that global warming is happening and will be disastrous. In contrast, ecologists have established that ecological systems are not steady-state and that species not only have evolved and adapted to change, but in fact many, perhaps most, require change.

Global warming Publications by Daniel B. Botkin

Books

1. Botkin, D.B., and E.A. Keller, 1987, Environmental Studies: Earth as a Living Planet (Columbus, Ohio: Charles E. Merrill), 500 pp. (2nd edition; 1st edition published 1982).

2. Botkin, D.B., M. Caswell, J.E. Estes, and A. Orio, eds., 1989, Changing the Global Environment: Perspectives on Human Involvement (New York: Academic Press).

3. Botkin, D.B., 1990, Discordant Harmonies: A New Ecology for the 21st Century (New York: Oxford University Press).

4. Botkin, D.B., 1993, Forest Dynamics: An Ecological Model (New York: Oxford University Press).

5. Skinner, B., S. Porter, and D.B. Botkin, 1999, The Blue Planet (New York: John Wiley & Sons).

6. Botkin, D. B., and E.A. Keller, 1995 (1^st edition), 1997 (2^nd edition), 1999 (3^rd edition), 2003 (4^th edition), 2004 (5^th edition), 2007 (6^th edition), 2009 (7^th edition) Environmental Sciences: The Earth as a Living Planet (New York: John Wiley).

7. Keller, E.A., and D.B. Botkin, 2007, Essential Environmental Science (New York: John Wiley).

Global Warming Articles and Reports by Daniel B. Botkin

1. Botkin, D.B., J.F. Janak, and J.R. Wallis, 1973, Estimating the effects of carbon fertilization on forest composition by ecosystem simulation, pp. 328-344, In G.M. Woodwell and E.V. Pecan, eds., Carbon and the Biosphere, Brookhaven National Laboratory Symposium No. 24, Technical Information Center, U.S.A.E.C., Oak Ridge, TN.

2. Botkin, D.B., 1977, Forests, lakes, and the anthropogenic production of carbon dioxide, BioScience 27: 325-33

3. Woodwell, G.M., R.H. Whittaker, W.A. Reiners, G.E. Likens, C.A.S. Hall, C.C. Delwiche, and D.B. Botkin, 1978, The biota and the world carbon budget, Science 199: 141-146.

4. Ralston, Charles W., G.M. Woodwell, R.H. Whittaker, W.A. Reiners, G.E. Likens, C.C. Delwiche, D.B. Botkin, 1979, Where Has All the Carbon Gone? Science, New Series, Vol. 204, No. 4399. (Jun. 22, 1979), pp. 1345-1346.

5. Botkin, D.B.,ed., 1980, Life from a Planetary Perspective: Fundamental Issues in Global Ecology. Final report NASA Grant NASW-3392. 49 pp.

6. Botkin, D.B., 1982, Can there be a theory of global ecology? Journal of Theoretical Biology, 96: 95-98.

7. Botkin, D.B., 1984, The Biosphere: The New Aerospace Engineering Challenge. Aerospace America, July 1984, pp. 73-75.

8. Botkin, D.B., J.E. Estes, R.M. MacDonald, M.V. Wilson, 1984, Studying the Earth’s Vegetation from Space, BioScience 34(8):508-514.

9. Botkin, D.B., and S.W. Running, 1984, Role of Vegetation in the Biosphere, Purdue University Machine Processing of Remotely Sensed Data (Symposium), pp. 326-332.

10. Davis, M.B., and D.B. Botkin, 1985, Sensitivity of the Cool-Temperate Forests and Their Fossil Pollen to Rapid Climatic Change, Quaternary Research 23:327-340.

11. Botkin, D.B., 1985, The Need for a Science of the Biosphere, Interdisciplinary Science Reviews,10(3):267-278.

12. Botkin, D.B., 1985, The Science of the Biosphere, Origin of Life, 15:319-325.

13. Orio, A.A., and D.B. Botkin, eds.,1986, Man’s Role in Changing the Global Environment, Proceedings of International Conference, Venice, Italy, 21-26 October 1985; The Science of the Total Environment 55: 1-399 and 56:1-415.

14. Bretherton, F.P., D.J. Baker, D.B.Botkin, K.C.A. Burke, M. Chahine, J.A. Dutton, L.A. Fisk, N.W.Hinners, D.A. Landgrebe, J.J. McCarthy, B. Moore, R.G. Prinn, C.B. Raleight, WV.H.Reis, W.F. Wee,s, P.J. Zinke, 1986, Earth Systems Science: A Program for Global Change, NASA Earth Systems Science Committee of the NASA Advisory Council, Washington, DC. 48pp + supplements.

15. Botkin, D.B. 1986, ed., Remote Sensing of the Biosphere, National Academy of Sciences, Washington, DC.

16. Botkin, D.B., 1989, “Science and The Global Environment,” pp. 3-14 (Chapter 1) in Botkin, D.B., M. Caswell, J.E.Estes, A.Orio, eds., Man’s Role in Changing the Global Environment: Perspectives on Human Involvement (Boston: Academic Press).

17. Stolz, J.F., D.B. Botkin, and M.N.Dastoor, 1989, “The Integral Biosphere”, pp. 31-49 (Chapter 3) in M.B. Rambler and L. Margulis, eds., Global Ecology:Towards a Science of the Biosphere (Boston: Academic Press).

18. Botkin, D.B., R.A. Nisbet, and T.E. Reynales, 1989, “Effects of Climate Change on Forests of the Great Lake States, pp.22-31 in The Potential Effects of Global Climate Change on the United States, J.B. Smith and D.A. Tirpak, eds. U.S. Environmental Protection Agency, Washington, DC, EPA -203-05-89-0.

19. Rosenfeld, A.H., and D.B. Botkin, 1990, Trees Can Sequester Carbon, Or Die, Decay, and Amplify Global Warming: Possible Positive Feedback Between Rising Temperature, Stressed Forests, and CO₂, Physics and Society 19:4pp.

20. Botkin, D.B., and L. Simpson, 1990, Biomass of the North American Boreal Forest: A step Toward Accurate Global Measures: Biogeochemistry 9:161-174.

21. Botkin, D.B., and L.G. Simpson, 1990, Distribution of Biomass in the North American Boreal Forest, pp. 1036-1045 in G. Lund, ed. Proceedings of the International Conference on Global Natural Resource Monitoring and Assessments: Preparing for the 21st Century, American Society for Photogrammetry and Remote Sensing.

22. Botkin, D.B., and R.A. Nisbet, 1990, Response of Forests to Global Warming and CO₂ Fertilization, Report to EPA.

23. Botkin, D.B., D.A. Woodby, and R.A. Nisbet, 1991, Kirtland’s Warbler Habitats: A Possible Early Indicator of Climatic Warming, Biological Conservation 56 (1): 63-78.

24. Botkin, D.B., 1991, Global Warming and Forests of the Great Lakes States: An Example of the Use of Quantitative Projections in Policy Analysis. An Essay submitted for the George and Cynthia Mitchell International Prize Competition, 1991, which won first prize and was published by the Mitchell Foundation, Houston, TX.

25. Botkin, D. B., 1991, Global Warming: What it is, What is Controversial About it, and What We Might Do In Response To It, UCLA J. of Environmental Law and Policy, 9: 119-142.

26. Botkin, D.B., R.A. Nisbet, S. Bicknell, C. Woodhouse, B. Bentley, and W. Ferren, 1991, Global Climate Change and California’s Natural Ecosystems, pp. 123-149 in J.B. Knox, ed., Global Climate Change and California: Potential Impacts and Responses (Berkeley: University of California Press).

27. Botkin, D.B., and R.A. Nisbet, 1992, Forest response to climatic change: effects of parameter estimation and choice of weather patterns on the reliability of projections, Climatic Change 20: 87-111.

28. Botkin, D.B., R.A. Nisbet, and L.G. Simpson, 1992, Forests and Global Climate Change, Chapter 19, pp. 274- 290 in S.K. Majumdar, L.S. Kalkstein, B.M. Yarnal, E.W. Miller, and L.M. Rosenfeld, eds., Global Climate Change: Implications, Challenges and Mitigation Measures, (Philadelphia: Pennsylvania Academy of Sciences).

29. Botkin, D.B., L.G. Simpson, and H.J. Schenk, 1992, Estimating Biomass, Science Letters.

30. Botkin, D.B., and R.A. Nisbet, 1992, Projecting the effects of climate change on biological diversity in forests, pp. 277-293 in R. Peters and T. Lovejoy, eds., Consequences of the Greenhouse Effect for Biological Diversity, (New Haven: Yale University Press).

31. Botkin, D.B., L.G. Simpson, and R.A. Nisbet, 1993, Biomass and Carbon Storage of the North American Deciduous Forest, Biogeochemistry 20: 1-17.

32. Simpson, L.G., D.B. Botkin, R.A. Nisbet, 1993, The Potential Aboveground Carbon Storage of North American Forests, Water, Air, and Soil Pollution 70:197-205.

33. Nisbet, R.A., and D.B. Botkin, 1993, Integrating a Forest Growth Model with a Geographic Information System, pp.265-269 in Goodchild, M.S., B.O. Parks, L.T. Steyaert, eds., Environmental Modeling with GIS (New York: Oxford University Press).

34. Hunsaker, C.T., R.A. Nisbet, D.C.L. Lam, J.A. Browder, W.L. Baker, M.G. Turner, D.B. Botkin, 1993, pp.248-264 in Goodchild, M.S., B.O. Parks, L.T. Steyaert, eds. Environmental Modeling with GIS (New York: Oxford University Press).

35. Guggenheim, D., and D.B. Botkin, 1996, CO₂ Offset Opportunities in Siberian Forests, Report to the Electric Power Research Institute, Center for the Study of the Environment, Santa Barbara, CA, EPRI report # TR-106059.

36. Botkin, D.B., 2001, “Energy and the Quality of Life,” Los Angeles Times, Sunday, June 10, 2001.

37. Botkin, D.B., Henrik Saxe, Miguel B. Araújo, Richard Betts, Richard H.W. Bradshaw, Tomas Cedhagen, Peter Chesson, Terry P. Dawson, Julie Etterson, Daniel P. Faith, Simon Ferrier, Antoine Guisan, Anja Skjoldborg Hansen, David W. Hilbert, Craig Loehle, Chris Margules, Mark New, Matthew J. Sobel, and David R.B. Stockwell, 2007, “Forecasting Effects of Global Warming on Biodiversity,” BioScience57(3): 227-236.

38. Bockstoce, J.R., D.B. Botkin, A. Philp, B.W. Collins, and J.C. George, 2007, “The Geographic Distribution of Bowhead Whales in the Bering, Chukchi, and Beaufort Seas: Evidence from Whaleship Records, 1849-1914,”2007 Marine Fisheries Review 67 (3) 1-43.

39. Botkin, D.B., 2007, The Future of Ecology and the Ecology of the Future, pp. 409-414 in Larry L. Rockwood, Ronald E. Stewart, and Thomas Dietz, eds., Foundations of Environmental Sustainability: The Co-Evolution of Science and Policy (New York: Oxford University Press).
40. Botkin, D.B., M.J. Sobel, L.G. Simpson, K. Cummins, and L.M. Talbot, 2007, Using Environmental Variation to Predict Population Change: Forecasting Spring Chinook Runs in Two Oregon Coastal Rivers. Report from The Center for the Study of the Environment available at www.naturestudy.org as a pdf file.

Underlying this belief that our environment has tipping points and we might be nearing one is a deeper belief: that the Earth’s environment is stable, that undisturbed by human influences it would be constant, or close to it.  Allied with this is the belief that our own actions are pushing the Earth toward the edge of a tipping point in ways that have never happened before.

The idea that our environment — nature, as it used to be called — is pretty much unchanging except for what we do is an ancient belief. It goes back to the Greek and Roman philosophers, who expressed it as the great Balance of Nature: that nature undisturbed achieves a permanence of form and structure, and that even when disturbed by us, if we then leave it alone, it will return to its harmonious constancy.

That idea has followed Western civilization down the ages, and in the 20th century was a fundamental belief even among ecologists — scientists who study the relationship between living things and their environment.  But as I’ve shown in my book Discordant Harmonies: A New Ecology for the 21st Century, nature has always changed.  All the climate reconstructions show that change is its only constant property.  To be more technical about this, modern science tells us that natural ecological systems and their environment are non-steady-state systems.  The old idea about nature being constant and able to return to its constant state after disturbance is based on a classical idea of stability — the stability of a machine, like the pendulum of an antique grandfather clock.  Once set in motion, the pendulum goes back and forth, but gradually friction slows it down and it comes to rest exactly where it started.

One of the things that makes it hard to accept the view of environment and ecosystems as out-of-steady-state and part of non-steady-state systems is that we haven’t had ways to think about how such systems change over time.  To make that possible, years ago I and my colleague Matthew Sobel — an applied mathematician, economist, and William E. Umstattd Professor at Operations Research at Case Western Reserve University — wrote a paper called “Stability in Time-Varying Ecosystems.”  (The paper was originally published as Botkin, D.B. and M.J. Sobel, 1975, “Stability in time-varying ecosystems” in  American Naturalist 109: 625 – 646.)

Briefly, we coined and defined two new terms for ecological systems that insist on changing all the time: persistence and recurrence. Instead of expecting an ecosystem, say of tundra near Barrow Alaska, or a population, say of polar bears, to remain constant, we expect instead that their numbers will vary, but within a certain range. This means the bear population will persist within certain limits, an upper and a lower number.  We call this persistence within bounds.  If we take actions that we think might harm the polar bear populations, we can check if there is an effect by comparing its past persistence with current ranges of variation.  (That is, of course, if we have the data to do this.  If we don’t, we’re out of luck as scientists and our management of polar bears lacks an important scientific base, but that’s another story.)

Recurrence is similar.  If an ecosystem or population is recurrent, then the condition it is in now will occur again in the future.  If a population is declining and on its way to extinction, its current population size is nonrecurrent.  Here’s another example.  In 1938 there were only 18 whooping cranes, and there was concern that this species would go extinct, and steps were taken to protect their habitat — their wintering grounds at Aransas National Wildlife Refuge, Texas and their summering grounds at Ramsar Wetlands in northern Canada.  This helped their population to increase greatly, and by 2007 scientists counted 237 at Aransas.  We who admire these cranes hope a population low of 18 never recurs — the population never gets that low again, but that 400 or even more could.

Tipping points don’t work for non-steady-state ecological systems, because they are always changing, kind of sloshing around from one condition to another, and they don’t really have cliffs to fall off of.  Life has persisted on Earth for about 3.5 billion years, during which it has evolved, changed, and adapted to changes many times.  Indeed, many of the changes life has adapted to were brought about by life itself, which has altered the environment locally and globally, adding to that sloshing among system states. Living things and their ecological systems do change a lot.  We can talk about changes that we like and those we don’t like, changes we consider natural or unnatural, but speaking of these as tipping points gets us off the track, away from how these things really work, and interferes with understanding what we could do, want to do, and even should do.

These are the general ideas.  If you want to get into the details, please read Matt Sobel’s and my paper.  Meanwhile, realize that tipping points only happen to steady-state systems, and our environment and ecosystems are not that kind.  There are many helpful ways to consider and discuss the possible effects of global warming.  Tipping points is not one of them.

by Daniel B. Botkin

NEW YORK:

Now that the Bali conference is over and climate scientists have warned us again about the dire predictions of their climate models, a question remains: Will their forecasts come true? Given the current international focus on global warming, you would think that, in 10, 15 or 20 years, many people will want to know whether today’s predictions proved accurate.

But, in fact, people rarely look back to see if their old forecasts were on the mark. Foretelling the future has always been difficult and almost always wrong. Charles Mackay, in his wonderful 1841 book “Extraordinary Popular Delusions and the Madness of Crowds,” observes that the so-called necromancers of earlier centuries who purported to divine the future were grouped with the worst alchemists. Today, however, computers seem to have undermined our natural skepticism. Many of us put our faith in complex software that most of us cannot understand.

My own experience makes me skeptical of how environmental forecasting is being used. In 1991, several colleagues and I drew national and international attention when we used a computer model to forecast possible effects of global warming on an endangered species. Our computer program forecast that the Kirtland’s warbler, the first songbird in America ever subjected to a complete census, would likely face extinction by 2010. Its habitat, jack pine trees, would be unable to thrive in conditions that climate computer programs forecast for southern Michigan, the only place and only trees where the bird nested.

The computer told us these declines should be measurable even in the year we made the forecast. We suggested that measurements of jack pine growth be started to verify the forecasts and to see whether the potential effects of global warming on the diversity of life were actually occurring. People could have started going to southern Michigan to check out our forecasts 16 years ago. Nobody did. I tried to get funding to do this, but no government agency or private foundation was interested.

Even today, amid the furor over global warming, no one is rushing out to verify that it does indeed threaten the Michigan jack pine. (But, happily, independent action by the government, the Audubon Society and private individuals has brought the Kirtland’s warbler back from the brink of extinction.)

What could explain the lack of interest in verifying a dated computer forecast? After all, computer forecasts are the basis for the current alarm. Did people perhaps decide that a 16-year-old forecast had to have been based on inferior methods?

But wait a minute. Given the usual progress of science, won’t forecasting methods in the future always be better than in the past? What this suggests is that today the primary uses of, and interest in, such forecasts are political, not scientific – that scientists as well as politicians are using forecasts for political and ideological purposes to influence public behavior here and now.

The question is not really whether the forecasts are scientifically valid, but how much impetus they can provide to influence society.

It wasn’t always this way. In the 1960s, when research into global warming was just beginning, it seemed impossible that people could change the global environment; the Earth was just too big. Charles Lyell, the father of modern geology, considered the possibility in detail in the mid-19th century and decided it was impossible because the mass of living things amounted to less than a drop in the bucket compared to the weight of all the materials in the oceans, atmosphere, soil and rocks.

In the 1970s, however, scientists began to realize that life had in fact greatly changed the Earth’s environment, starting more than a billion years ago. At the same time, evidence was building that burning fossil fuels was increasing the atmospheric concentration of carbon dioxide. In 1957, Charles Keeling began the first continuous measurements to study carbon-dioxide change over time at Mauna Loa, Hawaii. By 1973, he reported at a landmark conference at Brookhaven National Laboratory on “Carbon and the Biosphere” that carbon dioxide showed a definite increase in 15 years, consistent with releases from burning fossil fuels. For those of us working on these issues, the scientific and environmental implications were vast.

Global environmental change began to become a political issue in the 1980s. Climatologists and astrophysicists showed that a nuclear war could put so much dust in the air that disastrous cooling would occur, the infamous nuclear winter. With the end of the Cold War, the focus shifted to global warming. At that time, climatologists explained that their computer models were crude approximations of the real atmosphere and pushed the limit of computer technology, requiring months of computing for a single simulation. You could accept either the results of these crude models or the less-formal projections by the most experienced meteorologists. The primary focus continued to be on the implications of what we knew.

In 1988, in a move that marked a shift to the politicization of forecasts, Congress asked the Environmental Protection Agency to report on the potential effects of global warming. Computer forecasting became much more complex; output from the huge climate models became input into ecological models. My projection for the little warbler was part of that work. The attempt was to be more realistic, but the result was that forecasts became more difficult to verify and also more alarming, thus drawing more and more public attention.

Thinking over this history, I see three primary uses of environmental computer forecasts: to understand the implications of what we know (Can living things change the global environment?); to know the future; and to influence public behavior. Only the first can be strictly scientific. The third is wandering farther and farther away from science.

Since proving the validity of long-term forecasts is difficult and the ultimate tests would take years, and since many scientists are alarmed at the dire scenarios, my colleagues are beginning to talk about whether it is O.K. to exaggerate and push forecasts that are not currently provable if the only way to get societies to act is to frighten people. I think it is not O.K. It is a short-term view, and even if it works, it will inevitably debase science and scientists.

Soothsayers have always tried to persuade people that they could predict the future. What is new today is that the incredibly powerful tools of science – nuclear weapons, flights to the moon, computers, iPods – have such huge implications for civilization that they may contain the seeds of their own destruction.

Thirty years from now, we will probably not be interested in today’s specific computer forecasts, but we may have lost our faith in science, a deeper and, to me, a more important problem.

—————

Additional information about the Kirtland’s warbler forecast:

The scientific paper for the original forecast is:

Botkin, D. B., D. A. Woodby, and R. A. Nisbet, 1991, Kirtland’s Warbler Habitats: A Possible Early Indicator of Climatic Warming, Biological Conservation 56 (1): 63-78.

Those interested in the forecasting method can download the computer model of forest growth, JABOWA, from website www.naturestudy.org and play around with it. The software is pretty easy to use, and you can grow your own forest, log it, test it against various global warming climate regimes, etc. It isn’t as sophisticated a computer game as you can get today, but it is ecologically realistic and is used in research around the world.

And if you really want to get into the science part of this in depth, there are other scientific papers, including:

Botkin, D. B., and R. A. Nisbet, 1992, Forest response to climatic change: effects of parameter estimation and choice of weather patterns on the reliability of projections, Climatic Change 20: 87-111.

Botkin, D. B. and R. A. Nisbet, 1992, Projecting the effects of climate change on biological diversity in forests, pp. 277 – 293 in R. Peters and T. Lovejoy, (Eds.) Consequences of the Greenhouse Effect for Biological Diversity, Yale University Press, New Haven.

In researching recent literature on global warming, I came across the following quote, made in 1990: “Our projections on global warming suggest that by the year 2000, we will begin to see rapid changes over vast areas. In parts of the North, we expect to see stately old trees beginning to die back. The warmer temperature will make many trees vulnerable to insect attacks and different blights. Hikers will increasingly find themselves among dead trees. Loggers will have to choose between harvesting the dead timber and glutting the lumber and paper industries. And the diebacks will affect water supply and erosion rates. It’s really overwhelming.”

I wondered what idiot made this forecast — and discovered that it was me, in Harper’s magazine. The complete reference is: Pollan, M., Daniel B. Botkin, Dave Foreman, James Lovelock, Frederick Turner, Robert D. Yaro. (1990). “Only Man’s Presence Can Save Nature.” Harper’s magazine (April issue) pp. 37-48.

Fifty years ago, a group of scholars and scientists — some of America’s greatest humanitarians — published a landmark book titled Man’s Role in Changing the Face of the Earth. It was one of the twentieth century’s major statements about how people and their civilizations had changed the environment. Not only did it paint the picture of what people had done that had harmed the environment, it suggested what people might do to improve the environment and at the same time improve the lot of humanity.

Nowadays we hear daily from the media and through the media about the threat of global warming and its potentially dire effects on people and the diversity of life on Earth. The general tenor of these pronouncements is negative for people. You get the sense that people, especially modern technological people, have done wrong by Mother Nature. Having thus sinned against nature, we are warned that we will suffer the consequences. There will be massive flooding and terrible storms, destroying our homes and ways of life; millions if not billions of people displaced, homeless, wandering. Fresh water will be hard to find; we will thirst and our crops will fail. Pestilences and plagues confined to tropical climates will spread, and many of us will die.

A dark picture of the future emerges that sounds like the Medieval explanation of the great plagues as mankind’s punishment for its sins. The obvious implication is that we environmental sinners must pay by becoming material and energy minimalists and misers.

But if a warmer world is inevitable, is it not worth asking what is the role of human beings in that world and how could we make that world livable? Can we more than mitigate the worst effects, perhaps create a globally warmed world where there is music, art, literature, swimming, boating, hiking, picnics, trips to wilderness, views of magnificent forests, wildlife, and ocean shores.

Some biological conservationists are using formal computer models to forecast where habitats for endangered species might be in the future. Sometimes this is cast only negatively, to assure us that our present parks and preserves are doomed. But sometimes there is a glimmer of hope, that perhaps our modern scientific tools and our technology could help us help other creatures and build a world of the future that has biodiversity, life’s wonderful variety, and might even be enjoyed by us.

Perhaps it is time to expand this constructive approach, to look back at the ways of thinking of scholars and scientists of the mid-twentieth century, who saw not only our dark side but also our bright side, and sought to move us and our civilizations to be better.

There are precedents for such positive approaches to dire environmental change. In the 1930s, in response in part to the Dust Bowl and in part to the Great Depression, the federal government, apparently from a conviction that writers, artists, and musicians, that human culture and creativity, were worthwhile and deserved support, set up the Works Project Administration including the Federal Writers Project, and provided things for creative people to do that would benefit them, as well as benefit creativity and society. Today, in a time when large federal agencies and projects are seen often as having serious drawbacks, there could be other paths to this goal: individual creativity, local initiatives, regional responses, actions from the private sector.

Those who don’t believe in global warming will probably say that this kind of activity would be a waste of money. Those who do think global warming is happening may think that this is the worst admission of our failure to avoid it. Those who believe that a democratic society only acts in panic faced with doom and gloom will oppose this as another way to assure that the worst will happen to the environment. But those who love the best of civilization and the best of human cultures and creativity should applaud this suggestion and begin thinking of the best ways to make the globally warmed future liveable and more. Those scientists and scholars who are convinced that global warming is our most likely future have a moral obligation to take constructive actions of the kind I am suggesting. Who will stand up to the challenge?

I will be putting up a list of things you can do, both to help reduce the emissions of carbon dioxide and other greenhouse gases, and to improve our lives in a global warming world.

As someone who has done research since 1968 on global warming and its possible effects on living things, I am impressed and surprised by the great amount of attention that the media, Congress, international bodies, and people in general are paying to this issue, which seemed to be ignored for so long. 

Over the years, people have often asked me whether global warming is happening or not, and whether the terrible possible effects are definitely going to happen or not.  I reply that this isn’t the right question, that we should think about global warming and its possible effects more like the way we think about buying insurance against other natural hazards and catastrophes.

I was on the faculty at the University of California, Santa Barbara for many years, and when I  moved there I became acquainted with earthquakes and wildfires.  I bought  a house there and asked one of my colleagues in the geology department who was an expert on earthquakes and asked if I should buy earthquake insurance.  “I don’t have it,” he said,  “and here’s why.  It’s expensive.  The deductible is $10,000.  If an earthquake strikes this part of California and does an average of $10,000 damage per house, this will bankrupt the insurance companies and the Feds will have to come in and bail them out and cover our costs anyway.  And it’s very unlikely that that bad an earthquake will happen in my lifetime anyway.  So I don’t have it.”  He was right — the damage of the next big earthquake did exceed the ability of the insurance companies to pay, and the Feds did have to come in and bail people out.

What he was evaluating was, first, the cost of the premium; second, the likelihood of the event; third, the effects (in dollar terms) of that event; and fourth, whether the insurance would likely pay off anyway.

People did the same kind of analysis for wildfires and came to the opposite conclusion. Everybody had that kind of insurance.  The premium was relatively cheap, wildfires were common and likely in one’s lifetime, the deductible was low; and the potential personal costs without insurance were disastrous.

What’s the equivalent of buying global-warming insurance?  Actions to lessen the rate of warming or offset potential effects of global warming.  The intriguing thing is that most of the actions we would take to “insure” ourselves would benefit us even setting aside the issue of global warming.  We would plant trees to take up carbon dioxide; and we would burn less coal, which, aside from its greenhouse gas contributions, is highly polluting both to mine and to burn (and especially hazardous for the miners). We would generate electricity from solar and wind energy, abundant in many places that do not have petroleum reserves; this would reduce international strife over access to oil and gas. We would increase plantings even in our cities, making urban life more pleasant.  We would lower our energy costs (when you take into account all the costs of fossil fuel energy including the oil depletion allowance and wars fought over petroleum resources. We would help save endangered and threatened species. Viewed this way, it would make sense to do the equivalent of buying global-warming insurance. 

Forget about empty debates as to whether or not global warming is going to bring catastrophe and whether it is our fault. Take action that is carefully chosen to both combat global warming and benefit living things with or without global warming. And be particularly careful not to act in such panic as to do things that are dangerous and  damaging to life on Earth.  In short, think about it the way my geologist colleague thought about buying earthquake and wildfire insurance in California.

Case in point: In 1991, I and several colleagues published a forecast about how global warming would effect the Kirtland’s warbler, an endangered species that nests only in Michigan. The state of Michigan had set aside 38,000 acres of jack pine forest, the only kind of forest in which this bird nested, and managed these for the warbler. 

The warbler nests only in young jack pine woodlands, and jack pine only comes in after a fire. It can’t grow in the shade of taller trees, so if there are no fires, jack pine disappears. Periodic fires set intentionally in the Kirtland’s warbler’s forest were benefiting the bird. This raised the question: if the climate warms and jack pine can no longer grow in the part of Michigan where the warbler nests, what will happen to the bird’s habitat? (For reasons not completely understood, the warbler only nests in a specific kind of sandy soil found only in southern Michigan, so the bird is unlikely to migrate north.)

The computer model of forest growth that I developed with colleagues at IBM Thomas J. Watson Laboratory (available to download at  www.naturestudy.org) forecast that by 2015 jack pine would decline significantly and the warbler would begin to get into trouble.
Oddly, although there is so much written and said about global warming, and although this 1991 prediction got the attention of newspapers around the world, no one has tried to see if the forecast is turning out ot be valid. Here’s an opportunity to test at least one global warming forecast. Why is nobody taking advantage of this test? (Stay tuned.)

Forecast Jack pine forest under present climate and 40 years in the future

These forecasts are based on the use of the JABOWA forest model (see www.naturestudy.org) and a standard climate model.

Copyright © 2007 Daniel B. Botkin