Those who promote the theory that mankind is responsible for global warming have been working for the past 20 years on a revisionist climate history. A history where climate was always in a harmonious state of balance until mankind came along and upset that balance.

The natural climate cycle deniers have tried their best to eliminate the Medieval Warm Period and the Little Ice Age from climate data records by constructing the uncritically acclaimed and infamous “hockey stick” of global temperature variations (or non-variations) over the last one- to two-thousand years.

Before being largely discredited by a National Academies review panel, this ‘poster child’ for global warming was heralded as proof of the static nature of the climate system, and that only humans had the power to alter it.

While the panel was careful to point out that the hockey stick might be correct, they said that the only thing science could say for sure is that it has been warmer lately than anytime in the last 400 years. Since most of those 400 years was during the Little Ice Age, I would say this is a good thing. It’s like saying this summer has been warmer than any period since…last fall.

These deniers claim that the Medieval Warm Period was only a regional phenomenon, restricted to Europe. Same for the Little Ice Age. Yet when a killer heat wave occurred in France in 2003, they hypocritically insisted that this event had global significance, caused by anthropogenic ‘global’ warming.

The strong warming that occurred up until 1940 is similarly a thorn in the side of the natural climate cycle deniers, since atmospheric carbon dioxide increases from fossil fuel burning before 1940 were too meager to have caused it. So, the ‘experts’ are now actively working on reducing the magnitude of that event by readjusting some ship measurements of ocean temperatures from that era.

Yet, they would never dream of readjusting the more recent thermometer record, which clearly has localized urban heat island effects that have not yet been removed (e.g., see here and here). As Dick Lindzen of MIT has pointed out, it is highly improbable that every adjustment the climate revisionists ever make to the data should always just happen to be in the direction of agreeing with the climate models.

Of course, global warming has indeed occurred…just as global cooling has occurred before, too. While the global warming ‘alarmists’ claim we ‘skeptics’ have our heads stuck in the sand about the coming climate catastrophe, they don’t realize their heads are stuck in the sand about natural climate variability. Their repeated referrals to skeptic’s beliefs as “denying global warming” is evidence of either their dishonesty, or their stupidity.

The climate modelers’ predictions of the coming global warming Armageddon is of a theoretical event in the distant future, created by mathematical climate models, and promoted by scientists and politicians who have nothing to lose since it will be decades before they are proved wrong. They profess the utmost confidence in these theoretical predictions, yet close their eyes and ears to the natural rhythms exhibited by nature, both in the living and non-living realms, in the present, and in the previously recorded past.

They readily admit that cycles exist in weather, but can not (or will not) entertain the possibility that cycles might occur in climate, too. Every change the natural cycle deniers see in nature is inevitably traced to some evil deed done by humans. They predictably prognosticate such things as, “If this trend continues, the Earth will be in serious trouble”. To them behavior of nature is simple, static, always in-balance – if not sacred…in a quasi-scientific sort of way, of course.

They can not conceive of nature changing all by itself, even though evidence of that change is all around us. Like the more activist environmentalists, their romantic view of a peaceful, serene natural world ignores the stark reality that most animals on the Earth are perpetually locked in a life-or-death struggle for existence. The balances that form in nature are not harmonious, but unsteady and contentious stalemates — like the Cold War between the United States and the former Soviet Union.

Meanwhile, humans are doing just what the other animals are doing: modifying and consuming their surroundings in order to thrive. The deniers curiously assert that all other forms of life on the planet have the ‘right’ to do this – except humans.

And when the natural cycle deniers demand changes in energy policy, most of them never imagine that they might personally be inconvenienced by those policies. Like Al Gore, Robert F. Kennedy, Jr., and Leonardo DiCaprio, they scornfully look down upon the rest of humanity for using up the natural resources that they want for themselves.

And the few who freely choose to live such a life then want to deny others the freedom to choose, by either regulating or legislating everyone else’s behavior to conform to their own behavior.

The natural climate cycle deniers’ supposedly impartial science is funded by government research dollars that would mostly dry up if the fears of manmade global warming were to evaporate. With contempt they point at the few million dollars that Exxon-Mobil spent years ago to support a few scientists who maintained a healthy skepticism about the science, while the scientific establishment continues to spent tens of billions of your tax dollars.

So, who has the vested financial interest here?

Even the IPCC in its latest (2007) report admits that most of the warming in the last 50 years might be natural in origin — although they consider it very unlikely, with (in their minds) less than 10% probability. So, where is the 10% of the global warming research budget to study that possibility? It doesn’t exist, because — as a few politicians like to remind us — “the science is settled”.

The natural climate cycle deniers claim to own the moral high ground, because they are saving future generations from the ravages of (theoretical) anthropogenic climate change. A couple of them have called for trials and even executions of scientists who happen to remain skeptical of humanity being guilty of causing climate change.

Yet the energy policies they advocate are killing living, breathing poor people around the world, today. Those who are barely surviving in poverty are being pushed over the edge by rising corn prices (because of ethanol production), and decimated economies from increasing regulation and taxation of carbon based fuels in countries governed by self-righteous elites.

But the tide is turning. As the climate system stubbornly refuses to warm as much as 95% of the climate models say it should be warming, the public is turning skeptical as well. Only time will tell whether our future is one of warming, or of cooling. But if the following average of 18 proxies for global temperatures over the last 2,000 years is any indication, it is unlikely that global temperatures will remain constant for very long.

The above graph shows an average of 18 non-tree ring proxies of temperature from 12 locations around the Northern Hemisphere, published by Craig Loehle in 2007, and later revised in 2008, clearly showing that natural climate variability happens with features that coincide with known events in human history.

As Australian geologist Bob Carter has been emphasizing, we shouldn’t be worrying about manmade climate change. We should instead fear that which we know occurs: natural climate change. Unfortunately, it is the natural climate cycle deniers who are now in control of the money, the advertising, the news reporting, and the politicians.

(edited 12:15 p.m. 7/26/09 for clarity)
(3:25 p.m. DOH! Hawaii IS part of the U.S…)

I’m getting a lot of e-mails asking about a new study by Clement et al. published last week in Science, which shows that since the 1950s, periods of warmth over the northeastern Pacific Ocean have coincided with less cloud cover. The authors cautiously speculate that this might be evidence of positive cloud feedback.

This would be bad news for the Earth and its inhabitants since sufficiently strong positive cloud feedbacks would have the potential of amplifying the small amount of direct warming from our carbon dioxide emissions to disastrous proportions.

The authors are appropriately cautious about the interpretation of their results, which are indeed interesting. The very fact that the only 2 IPCC climate models that behaved in a manner similar to the observations were the most sensitive AND the least sensitive models shows that interpretation of the study results as proof of positive cloud feedback would be very premature.

But how could such a dichotomy exist? How could what seems to be clear evidence of positive feedback in the observations agree with both the climate model that predicts the MOST global warming for our future, as well as the model that predicts the LEAST warming for our future?

In my view, the interpretation of their results in terms of cloud feedback has the same two problems that previous studies have had. These problems have to do with (1) the regional character of the study, and (2) the issue of causation when analyzing cloud and temperature changes.

Problem #1: Interpretation of Feedbacks from a Regionally-Limited Study
Back in 1991, Ramanathan and Collins published a paper in Nature which indirectly argued for negative cloud feedbacks based upon the observation that regional warming in the deep tropics is accompanied by more convective cloud (thunderstorm) activity, which then shades the ocean from solar heating. This was the basis for what became known as the “Thermostat Hypothesis”, an unfortunate name since there are many potential thermostatic mechanisms in the climate system.

But as subsequently pointed out by other researchers, cloud feedbacks can not be deduced based upon the behavior of only one branch of vertical atmospheric circulation systems — in their case the ascending branches of the tropical and subtropical atmospheric circulation system known as the Hadley and Walker circulations. This is because a change in the ascending branch of these circulations, which occurs over the warmest waters of the deep tropics, is always accompanied by a change in the descending branch, and the two changes usually largely cancel out.

The new Clement et al. study has the same problem, but in their case they studied changes in the strength of one portion of the descending branch of an atmospheric circulation system, generally between Hawaii and Mexico, where there is little precipitation and relatively sunny conditions prevail. So, even if the regional cloud response they measured was indeed feedback in origin (the ‘causation’ issue which I address as Problem #2, below), it must be lumped in with whatever regional changes occurred elsewhere in concert with it before one can meaningfully address cloud feedbacks.

Unfortunately, further complicating feedback diagnosis is the fact that these atmospheric circulation cells are interconnected all around the world. And since cloud feedbacks are, strictly speaking, most meaningfully addressed only when the whole circulation system is included — both ascending and descending branches — we need global measurements. Except for our relatively recent satellite monitoring capabilities, though, we do not have sufficiently accurate cloud measurements over all regions of the Earth to do this over any extended period of time, such as the Clement study that used ship observations extending back to the 1950s.

But there is a bigger – and less well appreciated — problem in the inference of positive cloud feedback from studies like that of Clement et al.: that of causation.

Problem #2: The Importance of Causation in Determining Cloud Feedbacks
I am now convinced that the causation issue is at the heart of most misunderstandings over feedbacks. It is the issue that I spend most of my research time on, and we have been studying it with output from 18 of the fully coupled climate models tracked by the IPCC, a simple climate model we developed, and with satellite data.

[As an aside, as a result of reviews of our extensive paper on the subject that was submitted to the Journal of Geophysical Research, we are revamping the paper at the request of the journal editor, and working on a resubmission. So, I am hopeful that it will eventually be published in some form in JGR.]

Using the example of the new Clement et al. study (the observation that periods of unusual warmth on the northeast Pacific coincided with periods of less cloud cover)…what if most of that warming was actually caused by the decrease in clouds, rather than the decrease in clouds being caused by the warming (which would be, by definition, positive cloud feedback)? In other words, what if causation is actually working in the opposite direction to feedback?

It turns out that, when a circulation-induced change in clouds causes a temperature change, it can almost totally obscure the signature of feedback — even if the feedback is strongly negative. This is easily demonstrated with a simple forcing-feedback model, which is what one portion of our new JGR paper submission deals with. It was also demonstrated theoretically in our 2008 Journal of Climate paper.

In other words, a cloud change causing a temperature change gives the illusion of positive feedback – even if negative feedback is present.

In the case of the new Science magazine study, one of the major changes seen in temperature and cloudiness (and other weather parameters) occurred during the Great Climate Shift of 1977, an event which is known to have been accompanied by changes in atmospheric circulation patterns, such as immediate and prolonged warming in Alaska and the Arctic. And since circulation changes can cause cloud changes, this is one example of a situation where one can be fooled regarding the direction of causation.

This issue of the direction of causation is not easy to get around. While I’ve found some researchers who think this is only a matter of semantics, and who claim that all we need to know is how clouds and temperature vary together, our 2008 J. Climate paper demonstrated that this is definitely not the case.

The bottom line is that it is very difficult to infer positive cloud feedback from observations of warming accompanying a decrease in clouds, because a decrease in clouds causing warming will always “look like” positive feedback.

Based upon the few conversations I have had with other researchers in the field on this subject, the issue of causation remains a huge source of confusion among climate experts on the subject of feedbacks. Even though our 2008 Journal of Climate paper on the subject outlined the basic issue, the climate research community has still failed to grasp its significance. Hopefully, the more thorough treatment we provide in our JGR resubmission will help the community better understand the problem — if it ever gets published.

Since fears of manmade global warming — and potential legislation or regulations of carbon dioxide emissions — are based mostly upon the output of climate models, it is important for people to understand the basics of what climate models are, how they work, and what their limitations are.

Climate Models are Computer Programs

Generally speaking, a climate model is a computer program mostly made up of mathematical equations. These equations quantitatively describe how atmospheric temperature, air pressure, winds, water vapor, clouds, and precipitation all respond to solar heating of the Earth’s surface and atmosphere. Also included are equations describing how the so-called “greenhouse” elements of the atmosphere (mostly water vapor, clouds, carbon dioxide, and methane) keep the lower atmosphere warm by providing a radiative ‘blanket’ that partly controls how fast the Earth cools by loss of infrared to outer space.

The equation computations are made at individual gridpoints on a three-dimensional grid covering the Earth (see image below).

In “coupled” climate models, there are also equations describing the three-dimensional oceanic circulation, how it transports absorbed solar energy around the Earth, and how it exchanges heat and moisture with the atmosphere. Modern coupled climate models also include a land model that describes how vegetation, soil, and snow or ice cover exchange energy and moisture with the atmosphere.

You can make computer visualizations of how these processes evolve as the model is run on the computer, such as the nice example shown below produced by Gary Strand at the National Center for Atmospheric Research (NCAR). This particular image shows sea surface temperatures, near-surface winds, and sea ice concentrations in one of the NCAR models at some point during a run of the model on a supercomputer. [Note the model does not have an actual physical shape in the computer…it is just a long series of computations.]

If you want to see how a climate model simulation evolves over time, a striking YouTube video of the NCAR CCSM climate model is shown here.

The Importance of Energy Balance in Climate Models

Climate models are usually used to study how the Earth’s climate might respond to small changes in either the intensity of sunlight being absorbed by the Earth, or in the case of anthropogenic global warming, the addition of manmade greenhouse gases that further reduce the atmosphere’s ability to cool to outer space.

For it is the balance between these two flows of radiant energy – solar energy in, and infrared energy out of the climate system — that is believed to control the average temperature of the climate system over the long run. If the two radiant energy flows are in balance, then the average temperature of the climate system remains pretty constant. If they are out of balance, the average temperature of the climate system can be expected to change.

If this fundamental concept of “energy balance” sounds foreign to you, it shouldn’t because it is part of your everyday experience. For instance, the temperature of a pot of water warming on the stove will only increase as long as the rate of energy gain from the stove is greater than the rate of energy loss by the pot to its surroundings. Once the pot warms to the point where the rate of energy loss equals the rate of energy gain, its temperature then will remain constant.

Similarly, the temperature of the inside of a car sitting in the sun will increase only until the rate at which sunlight is absorbed by the car equals the rate at which heat is lost by the hot car to its surroundings.

In the same manner, any imbalance in the average flows of energy in and out of the climate system can be expected to cause a temperature change. When averaged over the whole Earth, the rates of absorbed solar energy and infrared energy lost are estimated to be about 235 or 240 Watts per square meter. I say “estimated” because our satellite system for measuring the radiative energy budget of the Earth is still not quite good enough to measure it to this level of absolute accuracy.

A variety of adjustable parameters in the model are tuned until the model approximates the average seasonal change in weather patterns around the world, and also absorbs sunlight and emits infrared energy to space at a global-average rate of about 235 or 240 Watts per sq. meter. The modelers tend to assume that if the model does a reasonably good job of mimicking these basic features of the climate system, then the model will be able to predict global warming. This might or might not be a good assumption – no one really knows.

It is also important to understand that even if a climate model handled 95% of the processes in the climate system perfectly, this does not mean the model will be 95% accurate in its predictions. All it takes is one important process to be wrong for the models to be seriously in error. For instance, how the model alters cloud cover with warming can make the difference between anthropogenic global warming being catastrophic, or just lost in the noise of natural climate variability.

Anthropogenic Global Warming in Climate Models

Our addition of carbon dioxide to the atmosphere by burning fossil fuels is estimated to have caused an imbalance of about 1.5 Watts per sq. meter between the 235 to 240 Watts per sq. meter of average absorbed sunlight and emitted infrared radiation. The extra CO2 makes the infrared greenhouse blanket covering the Earth slightly thicker. This energy imbalance is too small to be measured from satellites; it must be computed based upon theory.

So, if the Earth was initially in a state of energy balance, and the rate of sunlight being absorbed by the Earth was exactly 240 Watts per sq. meter, then the rate of infrared loss to outer space would have been reduced from 240 Watts per sq. meter to 238.5 Watts per sq. meter (240 minus 1.5).

This energy imbalance causes warming in the climate model. And since a warmer Earth (just like any warmer object) loses infrared energy faster than a cool object, the modeled climate system will warm up until energy balance is once again is restored. At that point, the rate at which infrared energy is lost to space once again equals the rate at which sunlight is absorbed by the Earth, and the temperature will once again remain fairly constant.

What Determines How Much the Model will Warm?

The largest source of uncertainty in climate modeling is this: will the climate system act to reduce, or enhance, the small amount of CO2 warming?

The climate model (as well as the real climate system) has different ways in which an energy imbalance like that from adding CO2 to the atmosphere can be restored. The simplest response would be for the temperature alone to increase. For instance, it can be calculated theoretically that the ~40% increase in atmospheric CO2 humans are believed to have caused in the last 150 years would only cause about 0.5 deg. C warming to restore energy imbalance. This theoretical response is called the “no feedback” case because nothing other than temperature changed.

But a change in temperature can be expected to change other elements of the climate system, like clouds and water vapor. These other, indirect changes are called feedbacks, and they can either amplify the CO2-only warming, or reduce it. As shown in the following figure, all 20+ climate models currently tracked by the United Nations’ Intergovernmental Panel on Climate Change (IPCC) now amplify the warming.

This amplification is mostly through an increase in water vapor — Earth’s main greenhouse gas — and through a decrease in low- and middle-altitude clouds, the primary effect of which is to let more sunlight into the system and cause further warming. These indirect changes in response to warming are called feedbacks. The models amplify the CO2 warming with positive water vapor feedback, and with positive cloud feedback.

But is this the way that the real climate system operates?

Uncertainties in Climate Model Cloud and Water Vapor Processes

The climate model equations are only approximations of the physical processes that occur in the atmosphere. While some of those approximations are highly accurate, some of the most important ones from the standpoint of climate change are unavoidably crude. This is because the real processes they represent are either (1) too complex to include in the model and still have the model run fast on a computer, or (2) because our understanding of those processes is still too poor to accurately model them with equations.

This is especially true for cloud formation and dissipation, which in turn has a huge impact on how much sunlight is absorbed by the climate system. The amount of cloud cover generated in the model in response to solar heating helps control the Earth’s temperature, so the manner in which clouds change with warming is of huge importance to global warming predictions.

Climate modelers are still struggling to get the models to produce cloud cover amounts and types like those seen in different regions, and during different seasons. The following NASA MODIS image of the western U.S. and eastern Pacific Ocean shows a wide variety of cloud types which are controlled by a variety of different processes.

The complexity of clouds is intuitively understood by everyone, experts and non-experts alike. It is probably safe to say that all climate modelers recognize that the modeling of cloud behavior accurately is very difficult, and is something which has not yet been achieved in global climate models.

All of the IPCC climate models reduce low- and middle-altitude cloud cover with warming, a positive feedback. This is the main reason for the differences in warming produced by different climate models (Trenberth and Fasullo, 2009). I predict that this kind of model behavior will eventually be shown to be incorrect. And while the authors were loathe to admit it, there is already some evidence showing up in the peer-reviewed scientific literature that this is the case (Spencer et al., 2007; Caldwell and Bretherton, 2009).

I believe that the modelers have mistakenly interpreted decreased cloud cover with warming in the real climate system as positive cloud feedback (warming causing a cloud decrease), when in reality it was actually the decrease in clouds that mostly caused the warming. This is basically an issue of causation: one direction of causation has been ignored when trying to estimate causation in the opposite direction (Spencer and Braswell, 2008).

The fundamental issue of causation in climate modeling isn’t restricted to just clouds. While warming will, on average, cause an increase in low-level water vapor, precipitation systems control the water vapor content of most of the rest of the atmosphere. As shown in the following illustration, while evaporation over most of the Earth’s surface is continuously trying to enhance the Earth’s natural greenhouse effect by adding water vapor, precipitation is continuously reducing the greenhouse effect by converting that water vapor into clouds, then into precipitation.

But while the physics of evaporation at the Earth’s surface is understood pretty well, the processes controlling the conversion of water vapor into precipitation in clouds are complex and remain rather mysterious. And it is the balance between these two processes — evaporation and precipitation — that determines atmospheric humidity.

Even in some highly complex ‘cloud resolving models’ – computer models that use much more complex computations to actually ‘grow’ clouds in the models – the point at which a cloud starts precipitating in the model is given an ad hoc constant value. I consider this to be a huge source of uncertainty, and one that is not appreciated even by most climate modelers. The modelers tune the models to approximate the average relative humidity of the atmosphere, but we still do not understand from ‘first principles’ why the average humidity has its observed value. We would have to thoroughly understand all of the precipitation processes, which we don’t.

In the end, many of the approximations in climate models will probably end up being not very important for forecasting climate change…but it takes only one critical process to be wrong for model projections of warming to be greatly in error. The IPCC admits that their largest source of uncertainty is low cloud feedback, that is, how low cloud cover will change with warming. And, as just mentioned, I believe how precipitation efficiency might change with temperature is also a wild card in climate model predictions.

Sources of Global Warming: Humans or Nature?

At this point hopefully you understand that climate modelers think global warming is the result of humans ‘upsetting’ the Earth’s radiative energy balance. And I agree with them that adding more carbon dioxide to the atmosphere must have some effect…but how large is this change in comparison the energy imbalances the climate system imposes upon itself?

It turns out that the modelers have made a critical assumption that ends up leading to the their conclusion that the climate system is very sensitive to our greenhouse gas emissions: that the climate system was in a state of energy balance in the first place.

There is a pervasive, non-scientific belief in the Earth sciences that nature is in a fragile state of balance. Whether it is ecosystems or the climate systems, you will hear or read scientists claims about the supposed fragility of nature.

But this is a subjective concept, not a scientific one. Still, it makes its way into the scientific literature (read the abstract to this seminal paper on the first satellite measurements of the Earth’s energy budget…look for “delicately balanced”). Just because nature tends toward a balance does not mean that balance is in any way ‘fragile’. And what does ‘fragile’ even mean when nature itself is always upsetting that balance anyway?

Why is this important to climate modeling? Because if climate researchers ignore naturally-induced climate variability, and instead assume that most climate changes are due to the activity of humans, they will inevitably come to the conclusion that the climate system is fragile: that is, that feedbacks are positive. It’s a little like some ancient tribe of people believing that severe weather events are the result of their moral transgressions.

If the warming observed during the 20th Century was due to human greenhouse gas emissions, then the climate system must be pretty sensitive (positive feedbacks). But if the warming was mostly due to a natural change in cloud cover, then the climate system is more likely to be insensitive (negative feedbacks). And there is no way to know whether natural cloud changes occurred during that time simply because our global cloud observations over the last century are nowhere near accurate enough.

So, climate modelers simply assume that there are no natural long-term changes in clouds, water vapor, etc. But they do not realize that in the process they will necessarily come to the conclusion that the climate system is very sensitive (feedbacks are positive). As a result, they program climate models so that they are sensitive enough to produce the warming in the last 50 years with increasing carbon dioxide concentrations. They then point to this as ‘proof’ that the CO2 caused the warming, but this is simply reasoning in a circle.

Climate modelers have simply assumed that the Earth’s climate system was in a state of energy balance before humans started using fossil fuels. But as is evidenced by the following temperature reconstruction for the last 2,000 years (from Loehle, 2007), continuous changes in temperature necessarily imply continuous changes in the Earth’s energy balance.

And while changes in solar activity are one possible explanation for these events, it is also possible that there are long-term, internally-generated fluctuations in global energy balance brought about by natural cloud or water vapor fluctuations. For instance, a change in cloud cover will change the amount of sunlight being absorbed by the Earth, thus changing global temperatures. Or, a change in precipitation processes might alter how much of our main greenhouse gas — water vapor — resides in the atmosphere. Changes in either of these will cause global warming or global cooling.

But just like the tribe ancient people not understanding that there are physical processes at work in nature that cause storms to occur, climate modelers tend to view climate change as something that is largely human in origin – presumably the result of our immoral burning of fossil fuels.

Faith-Based Climate Modeling

There is no question that much expense and effort has gone into the construction and improvement of climate models. But that doesn’t mean those models can necessarily predict climate 20, 50, or 100 years from now. Ultimately, the climate researcher (and so the politician) must take as a matter of faith that today’s computerized climate models contain all of the important processes necessary to predict global warming.

This is why validating the predictions of any theory is so important to the progress of science. The best test of a theory is to see whether the predictions of that theory end up being correct. Unfortunately, we have no good way to rigorously test climate models in the context of the theory that global warming is manmade. While some climate modelers will claim that their models produce the same “fingerprint” of manmade warming as seen in nature, there really is no such fingerprint. This is because warming due to more carbon dioxide is, for all practical purposes, indistinguishable from warming due to, say, a natural increase in atmospheric water vapor.

The modeler will protest, “But what could cause such a natural change in water vapor?” Well, how about just a small change in atmospheric circulation patterns causing a decrease in low cloud cover over the ocean? That would cause the oceans to warm, which would then warm and humidify the global atmosphere (Compo and Sardeshmukh, 2009). Or how about the circulation change causing a change in wind shear across precipitation systems? This would lead to a decrease in precipitation efficiency, leading to more water vapor in the atmosphere, also leading to a natural ‘greenhouse’ warming (Renno et al., 1994).

To reiterate, just because we don’t understand all of the ways in which nature operates doesn’t mean that we humans are responsible for the changes we see in nature.

The natural changes in climate I am talking about can be thought of as ‘chaos’. Even though all meteorologists and climate researchers agree that chaos occurs in weather, climate modelers seem to not entertain the possibility that climate can be chaotic as well (Tsonis et al., 2007). If they did believe that was possible, they would then have to seriously consider the possibility that most of the warming we saw in the 20th Century was natural, not manmade. But the IPCC remains strangely silent on this issue.

The modelers will claim that their models can explain the major changes in global average temperatures over the 20th Century. While there is some truth to that, it is (1) not likely that theirs is a unique explanation, and (2) this is not an actual prediction since the answer (the actual temperature measurements) were known beforehand.

If instead the modelers were NOT allowed to see the temperature changes over the 20th Century, and then were asked to produce a ‘hindcast’ of global temperatures, then this would have been a valid prediction. But instead, years of considerable trial-and-error work has gone into getting the climate models to reproduce the 20th Century temperature history, which was already known to the modelers. Some of us would call this just as much an exercise in statistical ‘curve-fitting’ as it is ‘climate model improvement’.

The point is that, while climate models currently offer one possible explanation for climate change (humanity’s greenhouse gas emissions), it is by no means the only possible one. And any modeler who claims they have found the only possible cause of global warming is being either disingenuous, or they have let their faith overpower their ability to reason.

Even the IPCC (2007) admits there is a 10% chance that they are wrong about humans being responsible for most of the warming observed in the last 50 years. That, by itself, shows that anyone who says “the science is settled” doesn’t know what they are talking about.

Conclusion

There is no question that great progress has been made in climate modeling. I consider computer modeling to be an absolutely essential part of climate research. After all, without running numbers through physical equations in a theoretically-based model, you really can not claim that you understand very much about how climate works.

But given all of the remaining uncertainties, I do not believe we can determine — with any objective level of confidence — whether any of the current model projections of future warming can be believed. Any scientist who claims otherwise either has political or other non-scientific motivations, or they are simply being sloppy.

REFERENCES CITED:

Caldwell, P., and C. S. Bretherton, 2009. Response of a subtropical stratocumulus-capped mixed layer to climate and aerosol changes. Journal of Climate, 22, 20-38.

Compo, G.P., and P. D. Sardeshmukh, 2009. Oceanic influences on recent continental warming, Climate Dynamics, 32, 333-342.

Intergovernmental Panel on Climate Change, 2007. Climate Change 2007: The Physical Science Basis, report, 996 pp., Cambridge University Press, New York City.

Loehle, 2007. A 2,000 year global temperature reconstruction on non-treering proxy data. Energy & Environment, 18, 1049-1058.

Renno, N.O., K.A. Emanuel and P.H. Stone, 1994. A Radiative-convective model
with an explicit hydrologic cycle: 1.Formulation and sensitivity to model parameters.
Journal of Geophysical Research, 99, 14,429-14,441

Spencer, R.W., W. D. Braswell, J. R. Christy, and J. Hnilo, 2007. Cloud and radiation budget changes associated with tropical intraseasonal oscillations, Geophys. Res. Lett., 34, L15707 doi:10.1029/2007GL029698.

Spencer, R.W., and W.D. Braswell, 2008. Potential biases in cloud feedback diagnosis: A
simple model demonstration, J. Climate, 21, 5624-5628.

Trenberth, K.E.., and J.T. Fasullo, 2009. Global warming due to increasing absorbed solar radiation. Geophysical Research Letters, 36, L07706, doi:10.1029/2009GL037527.

Tsonis, A. A., K. Swanson, and S. Kravtsov, 2007. A new dynamical mechanism for major climate shifts. Geophysical Research Letters, 34, L13705, doi:10.1029/2007GL030288.

(edit at 3:10 pm CDT: changed “tropics” to “Southern Hemisphere”)

YR MON GLOBE   NH   SH   TROPICS
2009   1   0.304   0.443   0.165   -0.036
2009   2   0.347   0.678   0.016   0.051
2009   3   0.206   0.310   0.103   -0.149
2009   4   0.090   0.124   0.056   -0.014
2009   5   0.045   0.046   0.044   -0.166
2009   6   0.001   0.032   -0.030   -0.003

1979-2009 Graph

June 2009 saw another — albeit small — drop in the global average temperature anomaly, from +0.04 deg. C in May to 0.00 deg. C in June, with the coolest anomaly (-0.03 deg. C) in the Southern Hemisphere. The decadal temperature trend for the period December 1978 through June 2009 remains at +0.13 deg. C per decade.

NOTE: A reminder for those who are monitoring the daily progress of global-average temperatures here:

(1) Only use channel 5 (“ch05”), which is what we use for the lower troposphere and middle troposphere temperature products.
(2) Compare the current month to the same calendar month from the previous year (which is already plotted for you).
(3) The progress of daily temperatures (the current month versus the same calendar month from one year ago) should only be used as a rough guide for how the current month is shaping up because they come from the AMSU instrument on the NOAA-15 satellite, which has a substantial diurnal drift in the local time of the orbit. Our ‘official’ results presented above, in contrast, are from AMSU on NASA’s Aqua satellite, which carries extra fuel to keep it in a stable orbit. Therefore, there is no diurnal drift adjustment needed in our official product.

I don’t think Al Gore in his wildest dreams could have imagined how successful the “climate crisis” movement would become. It is probably safe to assume that this success is not so much the result of Gore’s charisma as it is humanity’s spiritual need to be involved in something transcendent – like saving the Earth.

After all, who wouldn’t want to Save the Earth? I certainly would. If I really believed that manmade global warming was a serious threat to life on Earth, I would be actively campaigning to ‘fix’ the problem.

But there are two practical problems with the theory of anthropogenic global warming: (1) global warming is (or at least was) likely to be a mostly natural process; and (2) even if global warming is manmade, it will be immensely difficult to avoid further warming without new energy technologies that do not currently exist.

On the first point, since the scientific evidence against global warming being anthropogenic is what most of the rest of this website is about, I won’t repeat it here. But on the second point…what if the alarmists are correct? What if humanity’s burning of fossil fuels really is causing global warming? What is the best path to follow to fix the problem?

Cap-and-Trade

The most popular solution today is carbon cap-and-trade legislation. The European Union has hands-on experience with cap-and-trade over the last couple of years, and it isn’t pretty. Over there it is called their Emissions Trading Scheme (ETS). Here in the U.S., the House of Representatives last Friday narrowly passed the Waxman-Markey bill. The Senate plans on taking up the bill as early as the fall of 2009.

Under cap-and-trade, the government institutes “caps” on how much carbon dioxide can be emitted, and then allows companies to “trade” carbon credits so that the market rewards those companies that find ways to produce less CO2. If a company ends up having more credits than they need, they can then sell those credits to other companies.

While it’s advertised as a “market-based” approach to pollution reduction, it really isn’t since the market did not freely choose cap-and-trade…it was imposed upon the market by the government. The ‘free market’ aspect of it just helps to reduce the economic damage done as a result of the government regulations.

The Free Market Makes Waxman-Markey Unnecessary

There are several serious problems with cap-and-trade. In the big picture, as Europe has found out, it will damage the economy. This is simply because there are as yet no large-scale, practical, and cost-competitive replacements for fossil fuels. As a result, if you punish fossil fuel use with either taxes or by capping how much energy is allowed to be used, you punish the economy.

Now, if you are under the illusion that cap-and-trade will result in the development of high-tech replacements for fossil fuels, you do not understand basic economics. No matter how badly you might want it, you can not legislate a time-travel machine into existence. Space-based solar power might sound really cool, but the cost of it would be astronomical (no pun intended), and it could only provide the tiniest fraction of our energy needs. Wind power goes away when the wind stops, and is only practical in windy parts of the country. Land-based solar power goes away when the sun sets, and is only practical in the sunny Southwest U.S. While I personally favor nuclear power, it takes forever to license and build a nuclear power plant, and it would take 1,000 1-gigawatt nuclear power plants to meet electricity demand in the United States.

And no one wants any of these facilities near where they live.

Fortunately, cap-and-trade legislation is not necessary anyway because incentives already exist – right now — for anyone to come up with alternative technologies for energy generation and energy efficiency. Taxpayers and consumers already pay for billions of dollars in both government research (through taxes) and private research (through the cost of goods and services) to develop new energy technologies.

Whoever succeeds in these efforts stands to make a lot of money simply because everything we do requires energy. And I do mean everything…even sitting there and thinking. Using your brain requires energy, which requires food, which requires fossil fuels to grow, distribute, refrigerate and cook that food.

Economic Competitiveness in the Global Marketplace

Secondly, when instituted unilaterally by a country, cap-and-trade legislation makes that country less competitive in the global economy. Imports and trade deficits increase as prices at home rise, while companies or whole industries close and move abroad to countries where they can be more competitive.

The Obama administration and congress are trying to minimize this problem by imposing tariffs on imports, but this then hurts everyone in all of the countries involved. Remember, two countries only willingly engage in trade with each other because it economically benefits both countries by reducing costs, thus raising the standard of living in those countries.

The Green Mafia

Third, cap-and-trade is a system that is just begging for cheating, bribing, and cooking the books. How will a company’s (or a farm’s) greenhouse gas emissions be gauged, and then monitored over time? A massive new bureaucracy will be required, with a litany of rules and procedures which have limited basis in science and previous experience.

And who will decide how many credits will initially be given by the government to each company/farm/industry? Does anyone expect that these decisions will be impartial, without political favoritism shown toward one company over another, or one industry over another? This is one reason why some high-profile corporations are now on the global warming bandwagon. They (or at least a few of their executives) are trying to position themselves more favorably in what they see to be an inevitable energy-rationed economic system.

Big Oil and Big Coal Will Not Pay for Cap-and-Trade

Fourth, it is the consumer – the citizen – who will pay for all of this, either in the form of higher prices, or reduced availability, or reduced economic growth. Companies have no choice but to pass increased costs on to consumers, and decreased profits to investors. You might think that “Big Business” will finally be paying their “fair share”, but Big Business is what provides jobs. No Big Business, no jobs.

The Green Jobs Illusion

Fifth, the allure of “green jobs” might be strong, but the economic benefit of those jobs is an illusion. The claim that many thousands of new green jobs will be created under such a system is probably true. But achieving low unemployment through government mandates does not create wealth – it destroys wealth.

Let me illustrate. We could have full employment with green jobs today if we wanted to. We could pay each other to dig holes in the ground and then fill the holes up again, day after day, month after month. (Of course, we’ll use shovels rather than backhoes to reduce fossil fuel use.) How’s that for a green jobs program?

My point is that it matters a LOT what kinds of jobs are created. Let’s say that today 1,000 jobs are required to create 1 gigawatt of coal-fired electricity. Now, suppose we require that electricity to come from a renewable source instead. If 5,000 jobs are needed to create the same amount of electricity with windmills that 1,000 jobs created with coal, then efficiency and wealth generation will be destroyed.

Sure, you can create as many green jobs as you want, but the comparative productivity of those jobs is what really matters. In the end, when the government manipulates the economy in such a fashion, the economy suffers.

And even if a market for green equipment (solar panels, windmills, etc.) does develop, there is little doubt that countries like China will be able to manufacture that equipment at lower cost than the United States. Especially considering all of our laws, regulations, limits, and restrictions.

So, What’s the Alternative?

If anthropogenic global warming does end up being a serious problem, then what can be done to move away from fossil fuels? I would say: Encourage economic growth, and burn fossil fuels like there is no tomorrow! Increased demand will lead to higher prices, and as long as the free market is allowed to work, new energy technologies will be developed.

As long a demand exists for energy (and it always will), there will be people who find ways to meet that demand. There is no need for silly awards for best inventions, etc., because the market value of those inventions will far exceed the value of any gimmicky, government-sponsored competitions.

Why are Politicians so Enamored by Cap-and-Trade?

Given the pain (and public backlash) the EU has experienced from two years’ experience with its Emissions Trading Scheme, why would our politicians ignore that foreign experience, as well as popular sentiment against cap-and-trade here at home, and run full-steam with eyes closed into this regulatory quagmire?

The only answer I can come up with is: more money and more power for government. As a former government employee, I am familiar with the mindset. While the goal of a private sector job is to create wealth, the government employee’s main job is to spend as much of that wealth as possible. A government agency’s foremost goal is self preservation, which means perpetuating a public need for the agency. The idea that our government exists to help enable a better life for its citizens might have been true 100 years ago, but today it is hopelessly naïve.

All Pain, No Gain

And finally, let’s remember what the whole purpose of carbon cap-and-trade is: to reduce future warming of the climate system. Even some prominent environmentalists are against Waxman-Markey because they do not believe it will substantially reduce carbon dioxide emissions here at home. To the extent that provisions are added to the bill to make it more palatable to politicians from agricultural states or industrial states, it then accomplishes even less of what it is intended to accomplish: reductions in carbon dioxide emissions.

And even if cap-and-trade does what is intended, the reduction in CO2 emissions as a fraction of global CO2 emissions will moderate future warming by, at most, around one tenth of a degree C by late in this century. That is probably not even measurable.

Of course, this whole discussion assumes that the climate system is very sensitive to our carbon dioxide emissions. But if the research we are doing is correct, then manmade global warming is being overestimated by about a factor of 5, and it is the climate system itself that causes climate change…not humans.

If that is the case, then nothing humanity does is going to substantially affect climate one way or the other. Indeed, given the fact that life on Earth depends upon the tiny amount of CO2 in the atmosphere, I continue to predict that more atmospheric CO2 will, in the end, be a good thing for life on Earth.

Yet, many politicians are so blinded by the additional political power and tax revenue that will come from a cap-and-trade system that they do not want to hear any good news from the science. For instance, in my most recent congressional testimony, the good news I presented was met with an ad hominem insult from Senator Barbara Boxer.

I can only conclude that some politicians actually want global warming to be a serious threat to humanity. I wonder why?