During the 1980's the terms greenhouse effect, greenhouse earth, and global warming haunted me everywhere. I could not escape tedious and sophomoric discussions of the theory and its ramifications in the popular press and television. Friends who had strenuously avoided taking any science during school now wanted to tell me all about entropy and the heat death of the Earth. People openly hostile to science and reason became celebrities and experts on the greenhouse effect1. It made some activists and their organizations wealthy on book royalties alone. It promoted political careers 2. I hated it.
The greenhouse effect
The earth is isolated except that it receives radiation from the sun, mainly in the form of infra-red and visible light, and either reflects this radiation back to space or reradiates it as long-wave radiation by virtue of its temperature. In principle, there is some average temperature at which the incoming and outgoing radiation are in balance as shown in Figure 1. This radiation temperature ought to equal the mean earth temperature, except for some little complications.
If the earth were completely uniform, had no atmosphere, oceans or life, and solar intensity never varied, then the mean temperature would be simple to calculate--250K is a rough figure. However, adding just a thin atmosphere of CO2 complicates radiative transfer. It makes the atmosphere slightly opaque to longwave radiation, while leaving it clear for visible light. The result is to lower longwave emissivity and warm the planet, or perhaps another way to view this is that it raises the level at which longwave radiation leaves the Earth to some height in the atmosphere. Adding water vapor to the atmosphere causes fantastic complications, because water vapor, in addition to acting like CO2 in lowering emissivity, leads also to clouds. Clouds not only reflect and absorb sunlight in varying and poorly understood ways3, they also radiate longwave from their tops. Now mean earth temperature and radiation temperature have no clear relation to one another. In brief, the Earth might maintain a radiation balance with a widely varying mean temperature, because clouds allow the possibility of emitting radiation from high above the surface. Thus, it is odd to a physicist, to this physicist at least, that mean earth temperature should cause intense public debate. It is even more odd that people treat mean earth temperature as proxy for the driving engine of climate and weather. The real driver is the transfer of energy along vertical and lateral temperature gradients.
Revenge of the Greenhouse effect
For a time I thought fears of greenhouse warming were waning. The eruption of Mt. Pinatubo in 1990 cooled the planet slightly while proponents of catastrophic global warming theories busied themselves with damage control. Because of extreme criticism they'd received over sloppy science, they had spent several quiet years explaining away discrepencies between the global warming hypothesis and observation4. In fact, they perfected during this time means of explaining how record cold, wet weather actually confirms a theory predicting withering heat and drought. They built a theory confirmed by each and every weather observation.
In one of the most surreal addresses ever given by a U.S. President, President Clinton stated in 1996 that a record outbreak of arctic air over the U.S., and the flooding of the Pacific Northwest, resulted from greenhouse warming of the Earth. I couldn't have been more surprised if he had stated that experiments he and the First Lady had recently done proved the existence of ESP. The President, however, knew this to be true because his advisors told him it was so. I shuddered to think of having to argue each and every occurence of extreme weather as not being the result of global warming. Real science is not equipped for such a task. However, the proponents of global warming are busy tying every observation of unusual ecology, weather, climate, chemistry, disease, animal migration, and maleformity to global warming.
Recent headlines note that scientists have scrutinized solar behavior and, having first found evidence that it caused the entire 20th century recent warming, now find no solar influence at all5. Therefore, man's burning of fossil fuels must be the culprit in global warming6. They have looked at the most recent few years of satellite temperature data, and have concluded that global warming is definitely upon us7. They have looked for climatic fingerprints, which, when dusted, show unambiguous whorls of impending doom from burning fossil fuels8. Notable among these works is S.H. Schneider's claim9 that the 20th century increase in air temperature is so unusually long (shown in Figure 2) that it represents an 80-90% probability of being man-caused by carbon dioxide. Both the figure itself, and the calculations that produce it, remind me of James Hansen's testimony to Congress on June 23, 1988. Hansen testified that the unusually hot summers of the mid 1980's represented a 99% certainty of being man-caused greenhouse warming10. Before swooning over all this certainty, however, consider several pertinent observations.
A sequence of unusually hot summers characterized the 1980s; but there also occurred several unusually severe frosts that heavily damaged the citrus fruit industry. Unusually dry soil and drought in the midwest during 1988 eventually gave way to saturated soil and flooding in 1993. The winter of 1992-1993 presented record cold temperatures, record snowfalls, and record number of days of snow cover in parts of the west and midwest. 1994 presented the eastern U.S. with its harshest winter in decades. In early March New York City braced to break its season record snowfall of 57" ¾ a record set in climatically less altered 1977. Tulsa, Oklahoma set a record for snowfall in one storm. Record cold temperatures occurred across the midwest and eastern United States. Yet, in the middle of all the record setting cold there occurred a record high temperature for February in Caribou, Maine.
The summer of 1995 was among the hottest on record in the western U.S., but eventually the record heat and drought gave way to record rainfall in the Pacific Northwest, and to the greatest outbreak of Arctic air in an outbreak that broke pipes across the U.S. and paralyzed the upper midwest.
What do these observations tell us? They seem to say that after a century of allegedly man-induced climate change, and a temperature increase that some characterize as unprecedented in Earth history, weather continues to operate much as it did in 1896. There are record cold days, record hot days, record snowfalls, early killing frosts, floods, droughts, and so forth. Factors which affect the supply and price of food, and demand for fuel and power, continue to work as usual. They indicate at least how poorly mean earth temperature indicates climate and its trend. Perhaps they indicate its irrelevance.
Does pre-history tell us anything?
Climate modelers are fond of large, complex computer programs they call global climate models (GCMs). These models are interesting in that they exhibit many characteristics of real climate, but they do not predict earth climate very well. If one were to input all climatological data for the year 1940, and leading up to it, for instance, these programs could not predict the present climate. Some scientists defend these models by showing that they predict the yearly variation in temperature very well11; but many non-computer, and non-sophisticated models can do that also12. Just because a computer simulation exhibits some behavior is no reason to presume the earth works the same way12a.
The greatest weather and climate calculator of all is the Earth itself. It calculates the equations of atmospheric motion in parallel, at unequaled speed, with absolute accuracy every day. Every conceivable climate found in a global climate model (except those known as "hothouse earth" and "white earth") the earth has already calculated. It has calculated its way through a ten-fold increase in CO2 and a warming of more than 10°C during the Cretaceous period, and yet found it possible to drop into subsequent ice ages; the depths of which may have been 20°C colder, in places, than the present. It somehow found its way out of the ice ages. Once global climate models reach these states scientists have to prod them back to reality. No wild perturbation of the earth has managed to produce a Venus-like thermal runaway in 4 billion years. It is unlikely to happen in the next century.
Examination of past climates (paleoclimatology) promises counterintuitive, but accurate, findings that simply do not appear in current global climate models. For example, the geological record indicates that past episodes of polar warming, much like the worry of greenhouse doomsayers, precede ice ages 13. Thus, geologic history hints at a negative feedback that the climate system must contain. I often presumed that these negative feedback mechanisms would be found either in the ocean sequestering of carbonate ion, or in some change to cloud cover that would increase albedo. A recent summary article in Nature 45 suggests that foraminifera provide another route and that the fossil record conatins evidence that this has worked once before. However, the work of paleoclimatologists, glaciologists, and geologists is largely ignored by global warming proponents. There is a strong trend in fact, apparent in some scientific work as well as in popular science, to presume that earth climate prior to the current epoch to have been extremely stable, and that life itself has come to depend on this stability. There is downright circular scientific study that seeks to prove it. Yet, even within the past thousand years climate variation has caused tremendous human suffering and dashed the fortunes of great nations.
Figures of certainty quoted by Hansen and Schneider depend on assumptions about the statistics of climate. They presume that climate is statistically stationary. A stationary, random process varies unpredictably from one time period to another. However, its average (or mean) and measures of its variation always remain constant. A world of stationary climate may show a varying temperature, but variations in the 1880s resemble those in the 1990s. Scientists could, in principle, collect records of temperature in such a climate over a decade, or a century, and then say with certainty how improbable is a particular future temperature observation.
Real climate doesn't behave like this. Temperature is unpredictable, but hot years tend to cluster together as do cold years. Warm decades, in turn, cluster together as do cold decades; and warm centuries cluster together, as do cold centuries. Mandelbrot refers to this tendency of climate as the Joseph Effect, after the prophet who foresaw seven fat years followed by seven years of famine. Clustering causes present climate depend to some extent on the distant past, and makes the present statistically unique. No matter how long the real temperature record we examine, we find it contains cyclic variations of different lengths; and, most likely, one cycle so long it appears to be a secular trend14. The engineer calls such a process 1/f. It has no constant average or variation. Its main feature is an endless succession of new climatic records (see Figure 3).
Thus, Hansen's statement of certainty means simply that if average temperature is a stationary process typified by the past 100 years, summer temperatures in 1988 were above 99% of those expected to occur. But climate is not stationary; it is 1/f; and, in a 1/f process we expect new high temperature records with a probability of 100%. From this viewpoint Hansen's figure of certainty doesn't appear especially significant; neither does the often quoted observation that six of the hottest years on record occurred in the 1980s.
Likewise Schneider's statement of certainty presumes stationary climate, and makes a further assumption that the 20th century warming is an isolated event in the past 1000 years. In his view each century is an independent trial, like the flipping of a coin. Sustained warming has occurred in only the present century, coincident with a unique rise in CO2, ergo, the 1 in 10 chance occurrence has happened15. It must be man-caused.
But does Schneider know that only the present century shows a warming? He does not. We know, without any doubt, that the past millenium exhibited a warming (the middle ages optimum) which peaked during the 13th century. An abrupt cooling, The Little Ice Age, followed, which resulted in a temperature minimum in the 17th or 18th century. A subsequent warming then followed-a warming of which the 20th century warming is, perhaps, but a part. Surely this suggests that a 1 in 10 chance occurrence did not take place; that the 20th century warming is, in fact, hardly unusual.
Carbon dioxide and climate
W.J. Humphreys, a famous meteorologist, once said that ``Many people, relying on their memories alone, insist that our climates are very different from what they used to be. Their fathers made similar statements about climates of earlier times, and so did their father's fathers . . . ; and the bulk of this testimony is that our climates are getting worse16.''
People have always believed that climate is becoming worse. The new twist added to this human pathology is that man now controls the climate and ought to do something about it. The catastrophic global-warming thesis identifies carbon dioxide released from various human activities as culprit. People often think this idea is new. Yet, even in Humphrey's time the theory of CO2 -caused climate change was already old, and some scientists had suggested a link between burning of fossil fuels and warming of the earth. Humphreys examined the question, and settled the matter for himself by observing that water vapor duplicates most of the infra-red absorption band of CO 2; and that CO2, itself, is already on the flat portion of the extinction curve. Eighty years ago physicists recognized that water vapor is the dominant greenhouse gas. Current calculations suggest that it is 100 times more potent than CO2, which is in turn 10 times more potent than methane16a. To see how truly distorted the public debate on the subject has become, one must only point out that methane is now routinely called a ``major greenhouse gas.17'' If this is so, how major must be water vapor?
Without the greenhouse effect of water vapor the earth would be inhospitably cold. Figure 4 shows a greenhouse history of three similar planets. The idea is modified from a text by James Walker entitled Evolution of the Atmosphere, but it has appeared in other places as well.The curve for Mars shows a planet with insufficient atmosphere, and placed too far from the sun, to raise its surface temperature much. On this world the greenhouse gases lie as frost on or under the surface18 .
The curve for Venus shows that having an opaque atmosphere, where the radiation balance obtains at the cloud tops, and being placed too close to the sun, results in a world hot enought to melt lead.
As the Little Bear's porridge was to Goldilocks, the Earth's placement from the sun and its greenhouse accumulation of water vapor make a world that is just right; a world of liquid seas and modest temperature. Could the earth become like Venus in runaway greenhouse warming? Only if there is some way to duplicate Venus' dense, CO2-dominated atmosphere, and to increase solar absorption high in the troposphere by a factor of two, or so, on Earth.
Global climate models often calculate mean earth temperature and temperature distributions on the basis of a doubling of CO2. Will CO 2 concentration ever double? I doubt it. Even pumping enough CO 2 into the atmosphere to double its concentration every 20 years will not actually double its ultimate concentration. My best reasons for this are technical and confined to the notes19, but a good economic reason is that we are very likely to have substitutes for the fuel uses of oil, gas, and coal within twenty or forty years20.
Considering how much carbon dioxide burning fossil fuel we have burned since 1800, very little of the product carbon dioxide actually appears in the atmosphere. Even so, the observed temperature rise is still too small for the rise in CO2, and hasn't risen steadily with increasing CO2 concentration. In fact, observed temperature doesn't resemble global warming expectations well at all, despite repeated attempts to demonstrate a correlation. Two curves (Figure 5), taken from recent and old works on greenhouse warming, show such attempts21.
Thumbnail of Figure 5. Click to see full figure.
Positive feedback as far as the eye can see
There always exists a possiblility of positive feedback, in which a modest increase in CO2 concentration produces a small temperature rise, which in turn leads to an increase in other greenhouse gases, or some other factor that increases temperature further. While the media has continued to focus on CO2 itself as the problem, most climate scientists, like Humphreys, have recognized the inability of CO2 to alter climate substantially, and their global climate models actually depend on positive feedback loops to accomplish the estimated 2-4°C warming of a doubling of CO 2.
Two such positive feedback effects are noteworthy. The first is that rising temperature will increase the amount of water vapor in the atmosphere greatly, which in turn raises temperature greatly21a. The second possibility is that rising temperature will increase plant respiration and reduce photosynthesis. The result being that vegetation itself becomes a source of more CO2.
I might point out that neither mechanism depends on increased CO2 as its initiator. Anything that causes Earth temperature to rise starts the positive feedback loop. This presents a problem. Engineers face the challenges of positive feedback everyday. No engineer has ever managed to build a system of any kind, dominated by positive feedback, that didn't eventually cause trouble. The squeal of a public address system and the runaway Chernoble reactor are but two examples. If Earth's climate were dominated by positive feedback, and yet has undergone large temperature extremes in the past, how has it managed anything like a stable climate?
There is no satisfactory answer to this except that the climate system contains large elements of negative feedback that go unrecognized.
The Testimony of Current Climate
If CO2 causes Earth temperature to rise, surely the 30% increase in CO2 since 1800 should be observed in the temperature record. Our most recent temperature trend, during the period of most rapid accumulation of carbon dioxide, appears generally negative22 although there is now disagreement about this. However, because of the possibility of a discrepancy, global warming proponents spent much energy attacking the problem of why Earth temperature behaves so unexpectedly.
Schlesinger and Ramankutty recently found a 50 - 80 year periodic variation in temperature records from North America, the North Atlantic and Europe. In their words the influence of this variation ``. . . has so far dominated the [greenhouse] induced warming, thereby obscuring the latter and confounding its detection 23.'' In other words, we'd have better evidence for global warming if only normal climate would cooperate. Other scientists have hypothesized that the true magnitude of global warming, which they characterize as unprecedented is apparently hidden by a natural cooling trend. Thus, they seek to explain an unobserved, but unprecedented warming trend, with an unprecedented and unobserved coincident cooling trend. These appear as Ad Hoc explanations.
Whenever observations of real climate won't cooperate, some scientists return to global climate models. R.J. Stouffer and colleagues at Princeton report 24 about what adding the North Atlantic conveyor does to their computer model of climate. The conveyor refers to a system of ocean surface currents that carry warm, salty water from the Caribbean to the Norwegian Sea, and which have a profound influence on the climate of the entire hemisphere. They ran a 1000 year-long simulation of climate with this model and found that earth temperature fluctuated up and down, but that none of the fluctuations lasted as long as what we observe in the 20th century. They conclude from this that the observed 20th century warming must be man-caused or the result of some process not included in their model. Since they haven't included thousands of possible processes in their model, however, we should be skeptical about what this says about man-caused warming. In fact, temperature proxies such as borehole temperaturs in glaciers and mercury levels in peat bogs suggest millenial temperature variations. Other, even worse, studies exist that replace observations of actual climate with simulated thousands and million of years of Earth climate from a global climate model. A fair criticism is that they contain circular reasoning.
The history of physics contains innumerable examples of research, good and bad, in which scientists are fooled by their biases. Fleischman and Pon's observation of cold fusion is an example; so is the Palmdale Bulge25 . Irving Langmuir referred to these as pathological science, and he attempted to outline certain characteristics that identify it26. The debate about global warming contains many of these characteristics. Some of those summarized below are mine, not Langmuir's, by the way.
1) Identification of signals that are barely resolvable27.
2) Ignoring contrary evidence irrespective of its quality28 .
3) Complaints about conspiracies and persecution29.
4) Ad hoc explanations of contrary evidence30.
5) Quibbling. Tailoring to fit present circumstances31.
6) Shoehorning. Fitting unrelated items into a global framework32 .
7) Exclusive dependence on confirming data33.
My examples for item 6 show that a silly season in science is upon us. Perhaps there is unopposable pressure to tie all research into the currently fadish worry so as to guarantee funding. Perhaps it is delusional. But everyone attempts to tie their work or cause to that of global climate change.
Examples of this tendency include: Calculating by how much beef cattle warm the planet. M.A.K. Kahlil calculated, basically at the behest of the "let's stop eating beef outfit," that beef cattle warm the planet by a mere 0.04°C per century34. The effect is actually incalculable, insignificant, and the calculation itself fatuous.
That dinosaurs' flatulence lead to their extinction at the end of the Cretaceous and a fatal geo-belch of CO2 lead to the mass extinction at the end of the Permian35. Heaven knows that enough catastrophes befell the dinosaurs within a very short time, now they suffer being drawn into the greenhouse debate.
That demonstrated migration of animals and plants away from increasing urbanization is, in fact, a need to move into climates cooler by temperatures of as little as 0.06°C.36
Oceanographers suggest fertilizing the ocean to bury carbon in the undecayed remains of plankton. Atmospheric scientists suggest whitening the sky to reflect more sunlight.
In one strange exchange, scientists who suggested planting Connecticut-sized kelp beds to sop up CO2 had their plan derided by environmentalists as dangerously arrogant. The enviromentalists suggested a better approach would be to plant (Connecticut-sized) forests of trees, although I fail to see the distinction.37
Most data proferred as evidence of global warming involves the mean earth temperature. This data set, trotted out each year, is not a raw, objective set of observations. It is a compilation involving a varying, in fact growing, number of reporting stations, that have changed location with respect to major nearby cities over time. It results from making large corrections to the raw data, and from lumping together data taken in various ways. The inconsistencies and weaknesses of this data set are not widely published 38. However, even ignoring these weaknesses, a significant shortcoming in using mean temperature is that it summarizes earth climate with a single parameter. Single parameter measures rarely manage to characterize complex systems well. For example, the single parameter measure, body weight, is applied (tongue in cheek) to Abe Lincoln and Humpty Dumpty in figure 6. Even though we can easily differentiate the two, body weight suggests they are indistinguishable.
Temperature is obviously one component of climate; but so are cloud cover, precipitation, humidity, windiness, distribution of temperature between night/day, distribution of precipitation between summer/winter, and length of growing season. Does mean temperature tell us very much about these factors? Not at all.
If average temperature, even as measured by the most reliable sets of historical data, doesn't adequately characterize climate, what does? Within the past 5 years climate scientists have attempted to formulate fingerprints of climate. These are measures that characterize climate accurately and unambiguously. If we are to demonstrate global warming unambiguously, a fingerprint is indispensible.
A true fingerprint of climate does not currently exist, but the consensus among global warming proponents is that either mean temperature and its trend, or the outcome of global climate models are the two best possibilities. In addition to observation of mean temperature trend, global warming proponents often point to three other significant temperature charateristics.
First, they say, the 20th century temperature rise is of unprecedented amplitude 39. I have already argued that this is not so, and even if it were, it would be statistically irrelevent. Second, they claim that the temperature rise is of unprecedented duration40, which I have shown is simply not so. Finally they argue that the rise is of unprecedented pace.
To place this last statement in perspective, examine figure 7, which shows the level of Lake Victoria over the past century41. Note the abrupt level change that occurs after 1960; a level change exhibited in other East African lakes; and, note also that the level had not returned to its former value after several decades. This level change occurred coincidentally with an abrupt change in atmospheric circulation. I note that the change is, for all purposes, instantaneous. Moreover, it suggests a climatic variation that switches between stable states. Such a system displays stationary statistics only if the state switching is uncorrelated. Our observation of 1/f noise suggests correlation of infinite time span, however. Recent glaciology suggests that Earth temperature possesses this same state switching behavior 42. Moreover the other graph in the figure shows how sea level has changed over the past 15,000 years. It is stated as fact by global warming proponents that current sea level rise is of unprecedented pace. However, the history of sea level places the current rate well below the average over the past 15,000 years.
The concept of fingerprint of climate is currently evolving. Several recent studies demonstrated very imaginative ways of examining temperature data; and have also found some perplexing aspects of earth climate. However, I do not see how we will construct a set of observations that can identify man-caused climate change except in unusual circumstances43.
The question of whether earth temperature is currently increasing seems to be open. Even conceding that burning fossil fuels is putting large amounts of CO 2 into the atmosphere, the question of whether man and CO2 , or some other factor is causing a rise in Earth temperature is unanswerable at present. However, a fundamental question is whether increasing Earth temperature is of any great consequence. I suppose that the answer is that it depends on how much the temperature actually changes, and what further consequences this has. Let me propose an answer.
The most important measures of a climate, both from the standpoint of agriculture and the natural environment, are the extreme values expected of temperature, rainfall, and so forth. For temperature, in particular, extreme low values seem more important than extreme high values. For instance, one unusual cold spell destroys an orchard that may have thrived over a period of 25 years during which local average annual temperature varied by many degrees centigrade. Average temperature for that year might not even show any trace of the disaster.
The winter of 1948-1949 provides a real example of such a disaster. The winter wreaked havoc across the western U.S. and northern Mexico, caused unprecedented damage to citrus and livestock businesses, and set records for low temperature and duration of snow cover. Yet, this winter counts among the warmest in the northern hemisphere over the past century.
Earth temperature has recovered somewhat from Mt. Pinatubo's cooling. The recent El Nino (1997-1998) caused average temperature to rise quite fast, but not unexpectedly, and some opportunists saw this as a means to publicize an acceleration of global warming. I expect journalists to soon pound us mercilessly with of stories about man-caused warming; and global warming proponents will offer more frightening scenarios of a world without winter. Lost in the debate, and in the distractions of the technology of computer modelling, is any understanding that the danger we face comes not as a climate too warm, but as weather too cold. I do not know that global warming will decrease extremes of cold weather. I suspect it may even increase it; but if global warming does put us farther away from this danger, it will provide a great service.
A note added in September 2000: Recently in Science Easterling et al emphasize that the risks we face from climate change do, indeed, come from climate extremes and not from the drift of climate averages.46)
1. Jeremy Rifkin, an activist of no known scientific training, was advertised on the Metropolitan State College Campus as an "Expert on the Greenhouse Effect" in 1991. Jessica Tuchman Mathhews, who jumps around from one scientific topic to another, but is actually a systems analyst, was advertized as a "greenhouse expert" on Bill Moyer's World of Ideas Sept 14, 1988. She opined that scientists had only recently discovered the greenhouse effect.
2. Earth in the Balance garnered Mr. Gore book royalties of $200,000 in one year; this from a book that is not fun to read.
3. R. Cess et al. Science. v. 267 27 Jan 1995, p. 496.
4. Philip Abelson, an editor of Science magazine, editorialized that "... if the situation is analyzed applying the customary standards of scientific inquiry one must conclude there has been more hype than fact." Science 31 March, 1990.
5. David Thompson. Science. V 268 7 Apr 1995 p. 59. Paired against "A fickle sun could be altering Earth's climate after all." Science, V 269, 4 Aug 1995, p. 633.
6. In fact, criminological metaphors are found throughout the debate. Such terms as "convict greenhouse gases," "killer gases," and so forth abound. We also notice dark warnings that acquiescing to any criticism, or giving critics any fuel for debate is "dangerous." Proponents are practicing a type of self censorship after having become sensitive about criticism. See for example a quote by Thomas Karl, Science 12 Jan 1996 p138.
7. Science v 268, 1567, 16 June 1995
8. The initial analyses, being those of Earth temperature trend alone, were so easily dismissed by knowledgable critics that proponents began a search for more complex spatial and temporal patterns of temperature change hoping to unambiguously identify a global warming pattern. Among these are: preferential warming of polar regions (which seems to be a general feature of Earth climate during warming episodes), preferential warming of nights, preferential warming of winters and so forth. The critics did proponents a great favor by forcing them to examine these more complex fingerprints. The critics have received no thanks for this, however. One criticism that I have concerning climatic finger- prints is that they are all suggested by global climate models rather than by a basic understanding of how climate works.
9. Science 21 Jan 1994.
10. In Hansen and Lebedeff Geophys. Res. Letters. Vol 15, n. 4, pp 323-326. We find the conclusion "... the 1987 global temperature relative to the 1951-1980 climatology is a warming of between 2 and 3 standard deviations. If a warming of 3 standard deviations is reached it will represent a trend significant at the 99% confidence level. However, a causal connection of the warming with the greenhouse effect requires examination of the expected climate system respoonse to a slowly evolving climate forcing, a subject beyond the scope of this paper." Six months later, in his testimony before congress Hansen stated "... the global warming is now sufficiently large that we can ascribe with a high (99%) degree of confidence a cause and effect relationship to the greenhouse effect." Obviously the science is being represented differently to different audiences.
11. Schneider S., Sci. Am. v 256, 72, May 1987.
12. For example, a simple model known as Spitaler's formula predicts average temperature per laitude well simply from fraction of land coverage. H. Lamb. Climatic History and the Future. 1977. Princeton University Press. p. 298.
12a. I could hardly believe what I was reading, but Freeman Dyson editorialized on this very topic, taking my point of view, in a recent APS newsletter.
13. Sci. News. Feb 8 1992 Ice from Fire. Geologists suggest that past growth of ice caps is connected initially with a warming of Polar regions, suggesting a major negative feedback loop.
14. Mandelbrot in a series of papers shows the 1/f dependence of a variety of geophysical processes including river discharge, precipitation, and so forth. Mandelbrot and Wallis. 1968. Water Resources Research. V. 4, 909-918; and, 1969, V. 5, 321-340.
15. I thought that Schneider meant to say 98-99% confidence because he has considered two 1/10 occurences, CO2 accumulation and temperature rise. Having assumed they are random and unrelated, he should have multiplied the factor of 1/10 for each. However, maybe he does not consider the CO2 accumulation to be a random occurence. Nevermind the correctness of the underlying assumptions.
16. W.J Humphreys. 1940. Physics of the Air. Dover Edition. p. 577. The discussion that follows this quote is valuable reading for anyone interested in a clear exposition of the isolated effect of CO2.
16a. Here I rate potency by the combined ability to absorb IR longwave radiation and the concentration of the gas in the atmosphere. Water vapor and carbon dioxide come out atop my list because of their relative concentration. The usual measure of potency considers only the sensitivity to unit change in concentration. This measurement method will enable many tiny risks to loom very large.
17. Sci. News. v 139 18 May 1991 p. 310. Rice: Methane risk rises.
18. See Science 31 March 1995, p. 1912, for a cool Hubble photograph of Mars enveloped in CO2 frost.
19. This is a long note, please bear with me. The effect of any step increase in CO2 to the atmosphere is accomodated in the ocean in two steps. Let us refer to the addition of 2.5x1015 kg of CO 2 as a virtual doubling of atmospheric CO2. I say virtual doubling because this would double the concentration if no CO2 could leave the atmosphere. Step one involves adding CO2 at constant alkalinity. The buffer system working to maintain this is
H2CO3 <-> H+ + HCO3- <->2H+ + CO3-2
Enough CO2 is absorbed in this step to keep the virtual doubling from ever changing the atmosphere by more than 75ppm. Actually there are other paths for the absorption of CO2 because the virtual doubling of CO 2 during the period of 1970 to 1990 didn't raise atmospheric levels even this much. In a second, slower, step, oceanic water comes into equilibrium with bottom sediments. One possible reaction is
H+ + Sediments <-> Na+ + Sediments
which prevents one from moving to the left in the first reaction above. The long term virtual doubling of atmospheric CO2 actually becomes a maximum increase of 6%. An interesting related calculation involves assuming that the step increase in CO2 decays in the atmosphere as dC = dCo e-t/to where C is concentration and to is a time constant. From the observed growth of CO2 from 1970 to 1990, I have estimated to as about 10 years. If the step release (dCo) is made in each and every time period forever more, and the buffering capacity of the earth is not saturated, then the ultimate increase in concentration is dCo/(1-e -dt/to), where dt is the time increment producing the step release dCo. Using 2.5x10 15 kilograms per twenty years and to of a decade leads to a 50% long term increase. See Ferrin Macintyre, Sci. Am.
20. Hydride metal systems could store sufficient hydrogen to power an automobile for long distances. The economics of producing hydrogen from water do not compete effectively with fossil fuels at the present time.
21. Gilbert N. Plass. 1959. Carbon Dioxide and Climate. Sci. Am. July 1959. The correlation shown is spurious because, as note number 22 below shows, GCMs predict no measureable correlation before 1983. Thompson, Science v 268, 7 Apr 1995, p. 64, shows a neat correlation between world temperature and CO2 increases 1860 to present, but note the extreme amount of processing of each data set. What are we looking at here?
21a. See the perspective on climate change entitled Just Add Water Vapor, David Rind, Science, 281, 1152-1153, 1998.
22. World Climate Review. V. 3, N. 2, Winter 1995, p. 16. In the Planet Watch section note the dismal correlation in both hemispheres between satellite temperature records and predictions of GCMs. Note also that GCMs predict no significant warming before 1983, leading me to point out that the correlation in the 1930's shown by Plass is probably spurious. There is now a dispute over the actual trend of satellite temperatures. I have trouble understanding why a decaying satellite orbit causes the satellite to view slightly too high in the atmosphere. The interested reader can ponder the topic by beginning at the web page http://wwwssl.msfc.nasa.gov/newhome/headlines/essd06oct97_1.htm A review in the September, 2000 Issue of Reviews of Geophysics by Cristie et al, shows once again that microwave soundings from satellites fails to demonstrate any clear temperature trend. Thus, while surface temperature data never fails to make new global temperature records year after year in the 1990s, the satellite data is really ambiguous and enigmatic.
23. Schlesinger and Ramankutty, again this reference is in Nature in early 1994, but I can't find my copy. The inability of GCMs to find climate trends as long as the 20th century warming underlies Schneider's statistical assessment of the significance of the warming. However, it is only the GCMs that cannot find long term temperature trends. The temperature proxies do indicate long temperature trends. See for example, Delia Oppo. 1997. Science. 278, 1244-1245.
24. Manabe, S. and R.J. Stouffer, 1993, Nature, 364, 215. Stouffer (et al?). Nature. Feb 17 1994.
25. The Palmdale Bulge provides an example of self sustaining delusion in the earth sciences. No one, to my knowledge, has ever documented the several year life of this amusing, and expensive, scare. It thus presents itself as an excellent M.Sc. thesis topic in history of science. I have included a brief synopsis at http://www.kilty.com/bulge.htm
26. Langmuir recounted these characteristics in a series of seminars at the General Electric Company in the 1950s. I have a list in volume 6 of my scientific notes, but I do not have a reference for the reader. I apologize. Check in mid 1980s issues of Physics Today, perhaps.
27. Considering the magnitude of the secular temperature and the magnitude of corrections and short term natural variation, observed temperature rise is not much beyond bare resolution. This is, in effect, the subject of Hanson, et al, Geophy. Res. Letters, v. 16, n. 1, pp49-52, January 1989.
28. The work of Hanson, et al, is largely ignored, as is criticism of S. Fred Singer, and other faculty at the University of Virginia, and so is that of contributors to the ICS Press book The Greenhouse Debate Reconsidered.
29. Stephen Schneider has complained openly about being the target of a disinformation conspiracy (Rocky Mountain News, Feb 20, 1990, p. 8). Other proponents like to accuse critics as being the hired guns of industrial and commercial enterprises, and thus duplicitous.
30. The time length constituting a trend varies according to desire and thus is ad hoc. Most of the explanations for why real climate isn't behaving as expected, containing as they do large unexplained mechanisms, are also ad hoc. Finally, James Hansen, has suggested that the recent satellite data ". . . are awfully close" to the expectations of global climate models. Since the observation show zero trend, I can only label Hansen's characterization as ad hoc.
31. Refer to note 10 for a good example of tailoring. However, we might note that the neglect to explain the role of water vapor, as is done often, is a form of quibbling also.
32. Virtually all observations of ecosystems and climate are now directly tied to global warming, no matter how tenuous or silly. Thus, global warming has lead to increased severity of hurricanes, cold weather, warm weather, drought, flood, rising sea level from melting of ice caps, increasing thickness of ice caps (thus to a simultaneous melting and growth of ice caps), infection among ocean mammals, migrations of land mammals, methane release from tundra and swamp, extinction of dinosaurs and other mass extinction, and the increase of statospheric H2O. The tying of research funding to global warming suggests a speculative hysteria usually reserved for financial panic. For example, the millions spent by Iowa State University to determine how much methane cattle produce.
33. The case of ozone depletion and UVB is more illuminating in this instance than any example I can quote on global warming. The only worry of any consequence of a depletion of stratospheric ozone is an increase in UVB at the Earth's surface. The more direct indication of danger then is the measurement of UVB. However, the mere suggestion of doing such a direct measurement brings near hysteria, leads to no funding, and may have lead to the firing of William Happer from the Clinton Administration. Direct measurement of UVB might deflate the ozone depletion worry completely. We would rather make expensive U2 flights to measure ClO, instead.
34. Drover's Journal. Beef may not hasten greenhouse effect. 7 Sep 1989.
35. Dinosaur flatulence (Rocky Mountain News summary of the work of Simon Brassell, Indiana U. geochemist). Another Killer Charged with Mass Extinction. Science, v. 270, 1 Dec 1995, p.1441.
36. Migrations set off by .06°C changes . There are many examples of this sort of work. Kirtland's Warbler--a casualty of the greenhouse effect? is the work of Dr. Dorothy B. Rosenthal at Cal. St. Long Beach. The bird is extremely picky about nesting in young Jack Pines in central Michigan. The claim is that 1C change in temperature will push the trees 100km north, out of their ideal sandy soil. (I suppose the implication is that the average temperature gradient is 1C per 100km in central Michigan.) Another example is Edith's Checkerspot Butterfly (Nature August 29, 1996, p. 765). This moth has vanished at various sites along the West Coast of North America. In both instances the vanishing of species occurs in regions becoming urbanized. What, therefore causes the change? In the case of the butterfly it is not obvious that there is any change, for the vanishing of colonies in certain areas may only indicate that these are sink areas for the species..
37. Several of these schemes are summarized in The Long Beach Press Telegram Saturday June 16, 1990.
38. The Greenhouse Debate Reconsidered. S. Fred Singer, Ed. 1992. ICS Press.
39. Ibid. Hansen and Lebedeff.
40. Ibid. Schneider.
41. H. Lamb. Climate, History, and the Modern World. Methuen publisher. 1982, p 17.
42. D. Paillard. 1998. The timing of Pleistocene glaciations from a simple multiple-state model. Nature. 391, 378-381.
43. The drying up of the Aral Sea over ill advised diversions of river discharge is a good example of a change that is decidedly man-caused. Yet, even this is not a climate change.
44. There are other potential benefits to the rise in carbon dioxide concentration in the atmosphere. One example is that plants better utilize available rainfall and soil moisture. Considering the short supplies of fresh water for expanding uses, this too is a benefit.
45. Birger Schmitz. 2000. Plankton cooled a greenhouse. Nature. News and Reviews. 407, 143-144. The plankton connection appears to be associated with an extreme spike of delta18O and delta13C and biogenic barium salts at the paleocene/eocene boundary.
46. D.R. Easterling et al. 2000. Climate Extremes: Observations, Modeling,
and Impacts. Science, 289, 2068-2074. Among the interesting facts brought out in
this review are: 1) there is no trend in heat waves, despite the media hysteria in
1980, 1988, and 1995, and that the only remarkable event is the high frequency of
such events in the 1930s. 2) There is some tendency toward fewer temperature extremes
both high and low, across New England, and an earlier arrival of the frost-free
season there by 11 days since the 1950's. 3) There are fewer days of frost over the
There are many areas for dispute in this report, not just with its emphasis on costs of weather disasters, which may result from non-climatic factors, but also with apparent picking and choosing of examples from here and there, then and now, etc. This sort of picking and choosing is bound to emphasize clusters of occurences that are otherwise random. There is insufficient information at times to demonstrate the significance of some trends. For example, does 1% increase per decade of extreme rain events mean 1 extra 2 inch rainfall per year, or 10? We don't know.