Report by the E.P.A. Leaves Out Data on Climate Change....Draw your own conclusions

Amazing. A hot button topic produces a reasoned dialogue.

Let's start with the EPA report. First, there is nothing unusual about a draft report from agency staffers getting edited. The unappreciated fact of life in Washington is that , although we have a Republican administration, the agencies are heavily staffed by liberal democrats. Staff is often at war with the agency heads and the White House. They knew this wording would be highly controversial, and saw it as a no lose proposition. Either get a radical enivornmental manifesto into offical policy or go whining to their media allies that the White House is against the environment.


That this is highly politicized can be seen from the fact that the networks all ran major pieces on it Wednesday evening. I only saw the CBS segment, which was a model of scare-mongering, uncritical floating of the most radical golbal warming horrors and a one sentence disclaimer from the White House. Unfortunately, the major media has decided this issue is closed to debate, no matter whatthe science says. Their stories are almost totally propaganda.

What about the initial question posed in this thread? Shouldn't we err on the side of caution? What's so bad about protecting our planet?

The answer is complicated but compelling in my judgment. Basically, the Kyoto treaty imposed draconian cutbacks on the use of fossil fuels by the US, even as it exempted "developing" countries like China and India, which are large scale polluters. Europe was also givne a dispensation from severe cuts due to the closing of the old east german factories which were big polluters. So we have a treaty that purported to address the crucial issue of climate change, but miraculously singled out the US for punitive measures while letting the rest of the industrialized world off with minor limits. This treaty was so flawed that 95 senators voted against it. The Clinton administration never even submitted it for ratification. Yet President Bush is assailed by Dan Rather for not following it.

So the Kyoto treaty is flawed and hoepless, but what about the broader issue? Shouldn't we be doing something? A basic principle of policy analysis is to balance the risk versus the reward, the cost of taking action against the risk of doing nothing. We know the costs of taking action, either alone or with other countries, would be enormous. To turn back the emissions of so-called greenhouse gasses to even 1995 levels would require a huge loss of gdp, double digit unemployment, massive governmetn deficits and unprecedented lifestyle restrictions. But what of the risks?

There are four basic questions that need to be answered in the affirmative to justify action. 1. Has there been global warming? 2. If so, has it been caused by mankind's activities? 3. If so, is it something we should be concerned about? 4. Is there anything we can do to reverse it?

Without getting into a lengthy treatise, suffice it to say there is respectable scientific disagreement on all these questions. It is significant to point out that dissenting scientists face severe consequences, as the university/government/media axis has decided , for varying reasons, that global warming is a clear and present danger. Government grants to "study" (meaning produce scary reports) about this issue keep many science departemtns afloat. Environmentalists see it as a method to force the public to get rid of wasteful private vehicles adn other modern conveniences they abhor. And our global competitors see it as a device to hobble our economy.

And what are these noxious "greenhouse gasses" we hear so much about? By far the most prevalent is carbon dioxide, which you and 4 billion Chinese are expelling with every breath.

What would be the easiest and most efficient way to reduce our emissions? Widespread adoption of nuclear power. Guess who's against that?
 
Im for Global warming.....think about it? If we start getting warmer, maybe all the Newyorkers and Canadians will stay out of Florida and go to Virginia!

Acid rain is a myth.....It's cause by volcanic eruptions ....and they are now finding that it helps forest....Take all the smoke and combustion ever put forth by all the cars ever produced on the earth....and it still is nowhere near as harmful as the Volcanic eruptions of Pintumo or Mt. St. Helens...Live your life and don;t listen to these idiots...for years they worried about the ICE CAP "melting" and raising the level of the ocean...Now some scientist have discovered that the ICE is already floating and there fore the level is the same due to displacement....Look at the dinosaurs...never had a car, factory or a land fill...yet they are extinct...the earth changes...get used to it
 
There is just so much bad science that I don't believe any of it. It has been shown that the ice core samples used to measure cooling and warming periods are way, way off. They interpret daily temp changes, could even be intraday, as years. They still use them.

Max
 
As for the "it seems reasonable" argument, don't forget that it once seemed reasonable to just about everyone to believe that the Sun revolved around the Earth and that heavy objects fell faster than light ones...

Global warming may turn out to be a real problem, but we seem to be a long way from being able to judge what's really happening. In the meantime, those who oppose global capitalism for other reasons are quite happy to give the benefit of the doubt to the theory, induce fear among (and gain support from) impressionable observers, and propose measures that would restrain economic growth and establish ever greater administrative control of industry.

As for climate change in particular, I ran across this interesting, skeptical discussion of the topic:

Climate change debate somewhat hazy

I've been dealing with climate science issues in detail for approaching a month today. As a result, I am amazed whenever I hear anyone say that "science shows" anything in the climate change debate. The plain fact is that normal scientific methods simply aren't applicable in the climate science area. Normally, you come up with a hypothesis and run experiments to check it. The trouble is that you can't run experiments with the climate. We have no other Earth to act as a control (anyone who points to Venus as an example is showing his ignorance there and then). The science can therefore only progress by building models, which, if acceptably accurate, might predict what will happen. But those models are based on theory. If they cannot predict what is currently happening (as we know from observation) accurately, there is something wrong with them and/or the underlying theory. Theorists, however, are often wedded to their theories.

Take, for example, the satellite temperature data. There has been a warming trend in measurements taken on the Earth's surface (although most of it happened in the early 20th century, and there is huge debate as to whether heat island effects and land use changes caused the change rather than any actual change in the Earth's global average temperature, which itself is a pretty meaningless statistic. But I digress). The greenhouse theory says that this warming should be reflected in the atmospheric temperature measurements. But it isn't. Satellite temperature data show no warming trend. This has led some prominent modellers to suggest recently the satellite data must be be incorrectly measured, and if you just add a few mathematical corrections, they fall into line with the models. QED. Except that the weather balloon data also show no warming trend, and back up the satellite data. You might remember that pre-Galilean astronomers used to perfrom complex mathematical adjustments to their measurements of the position of the planets to back up their model of the Sun revolving around the Earth.

Anyway, this is all shown again in recent scientific debates surrounding the role of aerosols in climate change. The last Intergovernment Panel on Climate Change (IPCC) didn't really consider the role of black carbon aerosols (ie. soot) in the atmosphere (the atmosphere is an incredibly complex thing). Yet half the world burns wood and dung for fuel and heat, producing vast amounts of soot -- the Asian "brown cloud" is just one example of its effects. Research into the effects of soot is strongly suggesting that it warms the atmosphere. A recent study from James Hansen, one of the founders of the global warming theory, estimates that black aerosols are responsible for much of the warming trend to date, which has been far less than the greenhouse theory suggests.

Yet there's another side to aerosols. Other, sulfate aerosol particles -- non-soot pollution, basically -- reflect energy, and are therefore held to cool the earth. The IPCC took these into account, suggesting that they therefore masked what was really happening with global warming (thereby explaining why the warming trend is less than the theory suggests) and that, as atmospheric pollution decreased, global warming would accelerate. Hansen's paper suggests that the two forms of pollution cancel each other out, thereby leaving the greenhouse theory open once again to the question why temperatures have not increased as much as they should.

So once again there is a revision of the theory. New Scientist reports how a group of scientists in Berlin have decided that the aerosol cooling effect must, in theory, be bigger than presently supposed. The original short Perspectives piece in Science magazine the workshop was based on had said that this might mean either that the earth’s temperature is more naturally variable than thought or that the climate is more sensitive to forcing than thought. The Berlin workshop settled on the latter, and produced the prediction that, when sulfate aerosol production wanes, the earth might warm between 7-10° C. based on the IPCC’s worst-case scenario. The worst-case scenario is based on the improbable idea that the entire world will raise itself to the economic output levels of the United States.

New Scientist admits that the calculations on which these dire predictions were “back-of-the-envelope” figures. Despite this extreme uncertainty, Will Steffen of the Swedish Academy of Sciences was quoted as saying that “the message for policy makers is clear: ‘We need to get on top of the greenhouse gas emissions problem sooner rather than later.’”

This is a perfect illustration of the way the greenhouse theory is manipulated. The base theory suggests warming that isn't happening to the extent it should. Science then suggests something else. A new theory is produced, or an old one updated, to make the new data fit with the base theory. Worst-case scenarios are dreamed up and promulgated, normally worse than before. Action is then demanded now from policy-makers to avert the worst-case scenario.

Whatever this is, it isn't real science. It's science distorted to fit a politically-accepted view of nature. Those who question the progress of the science are vilified and pilloried. Galileo would recognize what's going on here, I think.
More...

http://volokh.com/2003_06_08_volokh_archive.html#200417645
 
Some don't like it hot:
James McCarthy knows what's around the corner
By Alvin Powell
Gazette Staff

While politicians argue, polar bears slowly starve.

A 1999 study of polar bears on Hudson Bay showed that rising temperatures are thinning the pack ice from which the bears hunt, driving them to shore weeks before they've caught enough food to get them through hibernation.

One of those trying to give the polar bears a break and settle the argument is James McCarthy, Alexander Agassiz Professor of Biological Oceanography and an internationally known authority on climate change. McCarthy was among a handful of top scientists who coordinated a remarkable report by the world scientific community this year that said global warming is real, it's here, and it's going to be worse than we thought.

"We already see effects that [indicate] the change in climate has occurred," said McCarthy, who also serves as director of the Museum of Comparative Zoology, head of the concentration on environmental science and public policy and Pforzheimer House master. "And the projection of some of those [effects] into the future are not a pretty scene."

McCarthy co-chairs of one of three working groups of the United Nation's Intergovernmental Panel on Climate Change (IPCC), a body established in 1988 to gather information on human-induced changes to global weather. Since its creation, the IPCC has released three assessments.

The Third Assessment Report was released in three parts over the past three months and states more clearly than ever that global warming is occurring. It also states for the first time that the evidence is overwhelming that humans are causing most of the change.

The report comes against a backdrop of international disagreement over how to curb rising levels of greenhouse gases in the atmosphere, largely carbon dioxide.

The United States and Europe are at odds over details of the 1997 Kyoto Protocol, which provides guidelines for the reduction of greenhouse gases. Opponents of the treaty, which has not been approved by the U.S. Senate, argue that it hurts developed nations and would limit economic growth in the United States.

President Bush added fuel to the debate this month – and infuriated environmental groups – when he announced he would not fulfill a campaign pledge to impose mandatory carbon dioxide reductions on power plants.

Atmospheric carbon dioxide slows the rate at which heat radiated by the Earth is lost to space. Carbon dioxide is a naturally occurring gas that is released and absorbed in a natural cycle. One illustration of that complex cycle is that animals, such as human beings, exhale carbon dioxide, which is absorbed by plants. The plants use the carbon dioxide and then release oxygen that humans can inhale.

Fossil fuels release carbon dioxide when they're burned, throwing the natural cycle out of balance and increasing the amount of carbon dioxide in the atmosphere.

The Third Assessment Report's release gained worldwide media attention and prompted speculation about such effects as the flooding of tropical islands, the flow of refugees from agricultural failure into Europe from Africa, and the disappearance of species that depend on specialized environments.


Tropical impacts

The report of Working Group II, which McCarthy co-chairs, talked about the potential impacts of projected global average temperature increases between 1990 and 2100 - which are expected to be in the range of two and a half to ten degrees. This four-fold range reflects varying future scenarios with different human populations, standards of living, and levels of environmentally-friendly energy sources.

The Working Group II report, released in February, painted a picture of tropical farmers unable to grow crops, a spread of tropical diseases such as malaria and cholera, and an increase in flooding from both heavy rains and rising seas.

One of the expected hallmarks of climate change, however, is its lack of uniformity. Talking about rising average temperature is almost misleading, McCarthy said, because the effects will vary in different parts of the world. Common all over, however, will be the increase in violent storms and extreme weather events, such as droughts and floods, as the atmosphere seeks to redistribute the new energy – in the form of heat – that it is absorbing.

Other major global shifts, such as changes to ocean currents, are less likely but possible. Should they occur, they could also have far-reaching effects. If the warm water current that flows across the North Atlantic were to slow or shift south, for example, temperatures in Europe, which typically experiences warmer temperatures than its northerly latitude would indicate, could plunge. Great Britain and Ireland, for example, are at about the same latitude as the southern tip of Hudson Bay, though their temperatures are much warmer. New England, by contrast, is at about the same latitude as the northern Mediterranean.

Barring those kinds of major shifts to the Earth's circulatory system, the brunt of the negative effects – floods, severe storms and drought – most likely will be felt by the world's poor, clustered in the tropical and subtropical latitudes. Exacerbating the problem is that it is the developed world, much of it further north, that has distribution systems and the technology to adapt to changing climate.

"What makes this more complicated is the fact that most of the problem has arisen, and most of the solution must arise, in parts of the world that are not likely to be as severely impacted as parts of the world that did little to contribute to this problem and have little resources to address it," McCarthy said.


'A conservative view'

McCarthy's colleagues at Harvard applaud the work of the IPCC for greatly increasing understanding among policymakers and the public about the scientific underpinnings of global warming.

But as alarming as one might think the IPCC's findings are, they very well may be understating the danger, according to Daniel Schrag, professor of geochemistry and director of the Laboratory for Geochemical Oceanography.

Schrag said the IPCC is by nature a conservative organization. The breadth that gives its findings weight – 3,000 scientists, reviewers, and government officials were involved in drafting the reports – means that consensus had to be reached across broad points of view, including those from countries whose economies are based on oil production.

"This is inevitably a conservative view," Schrag said. "This isn't something coming from Greenpeace."

Schrag points out that the IPCC's projections are just that – projections. Humankind is conducting a gigantic experiment to see what happens when you rapidly increase carbon dioxide to levels not seen for 40 million years. And no one knows the outcome, he said.

"This is an experiment that hasn't been done on the Earth for a very long time," Schrag said.

John Holdren, Heinz Professor of Environmental Policy at the John F. Kennedy School of Government, credited the IPCC with largely ending the debate over whether human-induced climate change is happening.

Holdren said he believes that global warming – which he prefers to term "global climate disruption" – will come to be known as an even more difficult problem than people today expect.

"I believe that global climate disruption will come to be understood over the next few decades as the most dangerous and most intractable environmental problem faced by civilization," Holdren said. "Up until now, it has been undersold more than oversold. Most people, even most scientists, do not understand the degree of dependence of human well-being on environmental conditions and processes that depend, in turn, on the climate."
 
Global Warming: Big Questions, Big Research


As mentioned previously, there is a great debate over whether or not humans are causing global warming. Some activists and researchers have resorted to name-calling or accusing the opposing side of having "sold out" to one special interest or another. As mentioned previously, we have attempted to cut away the personal attacks between the opposing sides, search for the kernel of truth (or logic, where truth cannot be discerned), and get down to the heart of the matter.

In order to properly read any of the reports or research on global climate change, one must keep in mind that nothing (or almost nothing) is certain. Everything has a certain degree of uncertainty, a certain flavor of the unknown. There really is no conclusive evidence of global warming, and many scientists in favor of the global warming hypothesis say that it will be a decade or more before it is possible to develop any substantial evidence. As an anonymous senior climate modeler has said about global warming, "The more you learn, the more you understand that you don't understand very much" (Kerr - Greenhouse Forecasting). Global climate is by nature always fluctuating, and that only adds to the confusion about anthropogenic global warming. If there were an anthropogenic global warming, we couldn't be sure what temperature we were supposed to be at, as climate shifts are a natural part of life on Earth. Compounding that confusion is natural variability, which is always working to confuse researchers just as they come close to attributing a perceived change in average temperature to some external factor, such as atmospheric composition (GHGs) or solar variation. One reason for this variability is the long adjustment time of the oceans' heat storage and current systems. It is estimated to take several hundred years for water to circulate from the deepest portions of the oceans back to the surface. This means that if, for example, a pool of extra cold water is singled out and stored in the depths by some freak mechanism, it could stay there a century or two before resurfacing and producing a local, cool climate change (Clarkson, North, and Schmandt).

Since no one can create another Earth (let alone one that behaves exactly like ours) and perform atmosphere-altering experiments on it, we are left with the alternative of theorizing based on observations. In other words, the only way we can purport to know anything about what might be changing in our climate is by playing with data, such as records of temperature, borehole measurements, etc., and seeing what scenarios the data will agree with.

Most of the body of global warming theory is based on computerized climate models called global circulation models or GCMs, for they are almost the only tools global warming researchers have. GCMs are difficult to make as making them properly involves a deep-rooted understanding of the way the atmosphere works and how its actions are interconnected with other planetary bodies, such as the oceans or the terrestrial biosphere. But our understanding of the inner workings of the atmosphere and the ways it relates to other planetary bodies is not very good. Renowned NASA climate modeler James Hansen, the man whose summer 1988 congressional testimony kicked off the climate change debate, states in the Proceedings of the National Academy of Sciences: "The forcings [outside factors] that drive long-term climate change are not known with an accuracy sufficient to define future climate changes." One of the fundamental illustrations of chaos, the butterfly effect, displays the interconnectedness of the atmosphere system when it states that a butterfly fluttering through the air in China could cause rain in New York the following spring.

GCMs are made by formulating mathematical descriptions of the interrelationships between the atmosphere/ocean/biosphere/cryosphere system and conducting numerical experiments. They certainly are unable to form a mathematical description based on the kind of interconnections, or feedbacks, that the butterfly effect would suggest. Indeed, Michael Schlesinger, modeler at the University of Illinois, Urbana-Champaign, tells us that "in the climate system, there are 14 orders of magnitude, from the planetary scale--which is 40 million meters--down to the scale of one of the little aerosol particles on which water vapor can change phase to a liquid [cloud particle]--which is a fraction of a millionth of a millimeter." Of these 14 orders of magnitude, only the two largest (the planetary scale and the scale of weather disturbances) can currently be included in models. Schlesinger notes that, to include the third order of magnitude (the scale of thunderstorms, at about 50 km resolution) a computer a thousand times faster would be necessary, "a teraflops machine that maybe we'll have in 5 years." Including all orders of magnitude would require 1036-1037 times more computing power (Kerr - Greenhouse Forecasting).

Because GCMs are so hard to make, often they account for the same processes differently; two models may have two different mathematical descriptions of what effect clouds have on warming, for example. Processes with a resolution smaller than a few hundred kilometers cannot be represented directly in the models, but instead must be parameterized, or expressed in terms of the larger scale motions, since the models do not have the resolution necessary to properly represent the actions of important weather systems such as tropical and extratropical cyclones. To offset this downfall, a few parameterizations (such as horizontal eddy viscosity, large-scale precipitation cumulus convection, gravity wave drag, etc.) are calibrated. Added to these parameterizations are adjustments commonly referred to as flux corrections, and they are an important "fudge factor" for the GCMs. These factors keep the models from floating off into nowhere. As Kerr (Model) stated, "Climate modelers have been 'cheating' for so long it's almost become respectable." Through these parameterizations, GCMs attempt to represent certain climate features reasonably well, but it is possible that they may be getting the right numbers but have the wrong underlying reason for them. As a result, such models' ability to simulate climate change properly would be negatively impacted.

Lately, a model has been designed and tested at the National Center for Atmospheric Research to eliminate the flux corrections. This model better incorporates the effects of ocean eddies, not by shrinking the scale, but by parameterization, passing the effects of these invisible eddies onto larger model scales using a more realistic means of mixing hear through the ocean that any earlier model did. This model doesn't drift off into chaos even after 300 years of running. This model gives a 2oC rise in temperature due to a CO2 doubling. (Some of the more popular GCMs assume that the concentration of CO2 will double in 70 years or quadruple in 140 years and use the assumption to try to predict what the climate will be like in decades or even centuries based on that doubling or quadrupling.) This figure is on the low side of estimates and puts the model's sensitivity to greenhouse gases near the low end of current model estimates (Kerr - Model).

GCMs are very sensitive to the representations of the effects of clouds and oceans, as their effects are complex and not understood well. While some GCMs are being specially made to simulate water behavior in clouds, limited vertical resolution (i.e., they don't go up far enough) and coarse horizontal resolution (i.e., the cloud activity of large areas of the Earth is averaged together and this average is used for the entire area) prevent even these models from accurately covering thin clouds and some cloud formation processes. Most early simulations were run with fixed cloud distributions based on observed cloud cover data, but these fixed levels didn't allow any feedback between cloud distributions and changing atmospheric/oceanic temperatures and motions. Problems in cloud feedback are seen as the Achilles heel of GCMs. Likewise, ocean representations were initially crude; in some early models, a swamp (stagnant, heat-absorbing, heat and water vapor-releasing body of water) was used as the oceanic model. Later models had a 50 meter thick slab of ocean that allowed summertime heat storage and wintertime heat release. While not including ocean currents (caused by the movement of heat to colder areas of ocean), these models attempted to represent seasonal responses to temperature in the upper ocean, but the lack of currents resulted in tropical oceans being too hot and polar regions too cold. Even today's most sophisticated, computationally-intense climate models are still just numerically experimental approximations of the exceedingly complex atmosphere/ocean/biosphere/cryosphere system. And yet, these GCMs are the basis of global warming theory, if for no other reason than the near-impossibility of conducting physical experiments at the global level (Cotton & Pielke).
 
The main means of testing these mathematical models of the climate involves taking climate data from previous years, running the programs, and seeing if the computer results are close to the actual present climatic data. The problem there is that the data are not exactly accurate. When the predicted global warming ranges from .5oC to 4oC, data accuracy is important, to say the least. Satellite data (view some) is called insubstantial by some researchers for the short length of its records, but Phil Jones states that the shortness even of global-scale surface temperature records (about 100 years) aids the uncertainty in the field.

Interestingly enough, current surface temperature measurements have shown a .5oC warming over the past century, but satellite measurements for the past fifteen years (satellite data has only been available for nineteen years) shows a slight downward trend. Satellite trends in temperature vary smoothly, while in some surface data, one region will appear to be warming while those regions around it appear to cool. According to Dr. Roy Spencer, a NASA scientist, "We see major excursions [from the trend] due to volcanic eruptions like [Mount] Pinatubo and ocean current phenomena like El Niño, but overall the trend is about 0.05 degrees Celsius per decade cooling" (Horack and Spencer). Earlier this year, it was realized that the satellite data needed correction for orbital decay, or "downward drift," in the satellites that cause erroneous cooling to show in the data. However, even after a careful readjustment the trend is still 0.01oC per decade of cooling, while weather balloons show -0.02 and -0.07oC per decade in Britain and America respectively, and British surface data show a warming of 0.15oC per decade.

The Intergovernmental Panel on Climate Change (IPCC) climate model predictions estimate surface warming to be 0.18oC per decade and warming in the deep layer measured by satellites and weather balloons to be about 30% faster, or +0.23oC per decade. None of the satellites or weather balloons show values anywhere near this, not even when the adjusted satellite record is updated through July 1998 to show a trend of +0.04oC per decade, which is still only 1/6 of the IPCC-predicted rate (Spencer).

Even while the satellites may need adjustments in their data for changes in orbit, this data is still more accurate than surface data. Satellites do not have anything in their surroundings to skew the data. On the other hand, many sources of error exist here on Earth. Things as seemingly minuscule as variation in the color and type of paint used for the instrument shelters can skew data slightly, for different types and colors of paint absorb small but differing amounts of solar radiation. As another example, the urban heat island effect is known to make cities warmer at night and milder during the day. The growth of urban areas during this century has resulted in a 0.4oC bias in the US climate record, making the amount of warming appear larger than it was (Cotton and Pielke). Thomas Karl, climatologist at the National Oceanic and Atmospheric Administration (NOAA), demonstrated in a 1989 paper that, if surface temperatures are corrected for the urban heat island effect, the years around 1940 emerge as the warmest, with readings since then showing a downward trend (Crandall). If this bias exists in the global climate data set, its use to represent a wider geographic record for climate change studies will be misleading.

Another largely-ignored factor affecting temperature data is solar variation, or periodic changes in the brightness of the sun based on sunspots and the like. Some climate modelers say that the Sun only varies with an 11-year cycle, and this period is too fast for the climate system to respond to. Hoyt points out that explosive volcanic eruptions have a one to two year long radiative forcing which does appear to affect climate, and so solar variance should have a substantial impact on climate. James Hansen, the famed NASA modeler, put it this ay: "Anthropogenic greenhouse gases (GHGs), which are well-measured, cause a strong positive (warming) forcing. But other, poorly measured, anthropogenic forcings, especally changes of atmospheric aerosols, clouds, and other land-use patterns, cause a negative forcing that tends to offset greenhouse warming.

One consequence of this partial balance is that the natural forcing due to solar irradiance changes may play a larger role in long-term climate change than inferred from GHGs alone" (NASA's). Current research by Daniel Cayan and Warren White of the Scripps Institution of Oceanography gives evidence that "the waxing and waning of the sun" may be behind current climate change. They studied North Pacific sea surface temperatures for the past 50 years and noticed that their pattern looked remarkably like that of satellite records of solar irradiance (Kerr - New). Based on this, it would seem logical to include these effects in GCMs, but few researchers do.

Moreover, any calculated warming would be reduced by this cooling effect of volcanoes. Even though we cannot predict the occurrence of a volcanic eruption, we have sufficient statistical information about past eruptions to estimate their average cooling effect; yet this is one of several factors not specifically considered by the IPCC (Singer - Scientific) and many other models.

If these models are wrong in their assumptions about climate, then everything that is thought to be known because of them is wrong. If, however, their assumptions are right, but essential factors or effects within the global system are being omitted from study, then GCMs thought to be wrong may actually need only an enlightened tweaking. Unfortunately, enlightenment is difficult to come by in this field. Many, many things are still unknown.
 
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