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Wednesday, February 14, 2007

My commentary on the draft IPCC report, submitted last spring

When the United States government solicited feedback on the draft IPCC report last spring, it asked commentators not to reveal what was in the draft report. Now that the IPCC has broken faith by releasing the its summary for policymakers three months before it releases the science, and is demanding that scientists adjust their science chapters to fit with the summary instead of vice versa, JunkScience.com has decided to post the draft report online. I agree with that judgment, and in the same spirit, will here post the properly submitted feedback that I attached to six cross referenced locations in the draft report.

It is clear from the summary that my feedback was sent to the circular file. Natural warming effects were completely omitted from the draft report, and they are completely absent from the summary. Still, readers might find it interesting to see just how this ruse works throughout the draft report.


My comment addresses the failure of the Fourth Assessment Report to include indirect solar effects in its analyses. I trace this failure through six locations in the Report, including the core conclusion of the report: that warming effects in the 20th century are primarily anthropogenic. The Report acknowledges that indirect solar effects are the only candidate for powerful natural warming effects. Evidence that some kind of powerful indirect solar effects exist is acknowledged. But indirect solar effects are then omitted from both the computer models that are discussed, and from the conclusions that are drawn based upon the computer models. The result is the classic problem of the omitted variable. Warming effects get misattributed to the greenhouse/anthropogenic effects that ARE included in the model. Thus the main conclusion of the Report is based entirely on elementary errors of logic and statistics.

To cross-reference, I am attaching the same comment to each of the five locations in the report where indirect effects are either mentioned or are errantly omitted.

Chapter 1, page 13 (i.e. page 1-13), lines 37-43
The direct effect of solar variation, through changes in total irradiance, is known to be small. Thus page 1-13, at lines 37-43, notes that if solar variation is to be a significant contributor to observed variations in global temperature, it must be through “unknown large feedbacks in the climate system,” such as effects on cloud nucleation. It goes on to note that mechanisms by which such indirect solar effects are at this point highly speculative and require more research. What is missing in this section is any acknowledgment of the large body of evidence that SOME kind of indirect mechanisms must be at work, given the numerous findings of strong correlations between solar activity and global temperature in the historic and geological records.

Chapter 2, page 56 (page 2-56), lines 5-17
The evidence for a correlation between temperature and solar activity, and the correlation itself, is only mentioned in one place in the entire report: 2-56, lines 5-17. Here it is noted that solar activity blocks some of the Galactic Cosmic Ray flux (GCR) from reaching earth, so that isotopes created by GCR and deposited in the geological record can be compared to temperature proxies, allowing correlations between temperature and solar activity to estimated from the geological record. The correlations are not described in their full strength, but the Report does at least note the GCR record shows that solar activity previously peaked during the Medieval Warm Period, and is as high today as it has ever been.

The problem is that this crucial correlation is never mentioned again, anywhere else in the entire report! In consequence, the implications of this known correlation are never properly accounted in the analysis.

Chapter 2, Page 2-56, line 38 through page 2-58, line 8
The omissions begin immediately after the above. Starting at 2-56, line 38, the report describes a couple of the proposed mechanisms by which solar activity might indirectly affect global temperature: the possible warming effects of the disproportionately high levels of UV light that accompany high levels of solar activity, and the possible effects of GCR on cloud nucleation. These particular mechanisms are seen to be theoretically incomplete and to bear an ambiguous relation to the evidence, but it is concluded (page 2-58, lines 1-8), that some combination of these mechanisms could end up consisting with the evidence.

Overall, what this section and its conclusion emphasize is the highly uncertain nature of the proposed mechanisms by which indirect solar effects might operate. What ought to be included in the conclusion is an acknowledgement of what is CERTAIN: that even if these PARTICULAR mechanisms are not borne out, it seems clear that that SOME indirect solar effect on temperature must be at work, given the known strength of the historical correlation between solar activity and temperature.

Chapter 9, page 25, line 54, through page 27, line 29
Where the omission of indirect solar effects becomes glaring, and perverts the conclusions arrived at, is in the discussion of the computer models in chapter 9. It is clear that the computer models being discussed do not include indirect solar effects. These models are described as including “solar output” (9-25, 56) but it is clear that the models only include direct solar effects because, in the one model cited as typical, it is estimated that “over the entire [20th] century, natural forcings gave a linear trend close to zero” (9-26, lines 7 and 8). Since the estimate for indirect solar forcings over the 20th century is that they rose drastically, it is clear that the model did not include these indirect forcings.

The Report should have noted at this point that the premises of the models being discussed were known to be at odds with the established evidence about natural forcings, which rose strongly during the century, even if we don’t completely understand the mechanism. But no hint that the models are known to be wrong appears.

This misfeasance continues throughout the rest of chapter 9. Page 9-26, lines 26-39, goes on to discuss another class of models which assume “a small net contribution from natural factors over the century.” Again, no note is made that this is known to be wrong. We may not understand the MECHANISM, but we know that there is SOME mechanism by which solar activity has a strong indirect affect on global temperature.

At each point, the Report describes how virtually all of the temperature variability of the 20th century is attributed by these models to changes in greenhouse gases and aerosols, and hence to human activity (since changes in greenhouse gases and aerosols have been caused by human fossil fuel burning). But these conclusions (culminating on page 9-27, lines 16-29) are obviously circular. Of course all temperature effects will be attributed to human activity, when what is known to be the primary natural source of temperature variation (indirect solar effects) has been excluded from the model.

This is known as the problem of the omitted variable. When an explanatory variable is left out of a statistical model, its explanatory power will be picked up by any variables that are correlated with it over the sample period (whether there is any causality behind the correlation or not). Since possible human-created causes of warming (the increase in greenhouse gases) correlates over the 20th century with the increase in solar activity (no causal relation), leaving indirect solar effects out of the model means that natural warming effects get misattributed as greenhouse gas effects.

This is a very basic and egregious error, made as baldly as can be, leads to the central conclusion of the report: that 20th century warming is anthropogenic in origin.

Page 9-30, lines 21 and 22
The closest the Report comes to acknowledging that it has omitted indirect solar effects is in the “Remaining uncertainties” section ( where it notes that “chemical and dynamical processes associated with the atmospheres response to solar irradiance are omitted or not adequately resolved.” (9-30, lines 21 through 22.) No mention is made that these un-modeled effects, whatever the specific mechanism involved may be, are KNOWN to be powerful. No mention is made of the known consequences that this omission for the results of the model: that the omission will cause known natural warming effects to be misattributed as human effects.

Page 9-38, lines 7 through 17
Most egregious is the conclusion of section 9.4.5 (page 9-38, lines 7 through 17) where it is asserted that the models used “include the most important forcings of the climate system” (line 11). This is simply a flat-out lie. Indirect solar forcings are KNOWN to be powerful, and they are NOT INCLUDED in the models used. Yes, there is an excuse for not including them: scientists are not sure HOW to include them. But there is no excuse for claiming that the most important forcings have been included when it is known that there are some very VERY important forcings that have not been modeled.

This flat-out lie is then used to support the central conclusion of the entire report: “that greenhouse gas forcing has very likely been the dominant cause of the observed global warming over the last 50 years.” (9-38, lines 14 and 15.)

Not dishonest enough for you? How about this freakish masterpiece of anti-human disinformation: “The fact that climate models are only able to reproduce observed temperature changes over the 20th century when they include anthropogenic forcings and their failure to do so when they exclude anthropogenic forcings is strong evidence for the influence of humans on global climate.” (9-38, lines 11 through 14).

No mention that the known primary natural forcings have been left out of the model, and that this is why temperature variations cannot be accounted for unless human forcings are included. If human forcings were also excluded from the model then ALL forcings would be excluded and of course no temperature variation would be possible!

The real evil of this disinformation comes in the implications for policy. If global warming since the 1970’s is substantially due to indirect solar effects, then we need to worry about the predicted fall off in solar activity from current highs. Statistical analysis of solar activity over time indicates a variety of regular cycles that are forecast to reach a minimum in about 2030. We could soon be facing strong natural cooling effects, in which case substantial amounts of anthropogenic warming could well be desirable. Policies that pay a high price to lessen human warming effects could easily turn out to be a double whammy, both exacerbating the climate problem, and lessening the economic strength we will need to adapt to a cooling earth.

The draft Report is deceitful and dangerous ideology. Please fix it.

Sincerely, Alec Rawls
Environmental writer for World Ahead Publishing, author of Kyoto chapter in World Ahead’s 2004 book Thank You President Bush.

Alec Rawls, alec@rawls.org

End of submitted feedback

According to the summary for policymakers, the current Fourth Assessment Report actually reduces warming due to solar effects by half, compared to the Third Assessment Report. Both only account "solar irradiance," or the direct warming effect of solar radiance. (See the middle of page 5 of 18.) Neither report includes any GCR blocking effects, or other indirect solar effects.

For more on indirect solar effects, see Fred Singer's new book, Unstoppable Global Warming, every 1500 years. I read it last week and it strips the hoax of human induced global warming naked. GREAT book. I also have Svensmark's new book The Chilling Stars on pre-order.

Related posts:

Global warming's omitted variable
NASA global-warmist James Hansen is a LIAR
Is Realclimate a part of the "reality based" community?

And for fun:
Earth Day 2030: "A new eye blinked open upon the world"

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