What's HotWorld Climate Report

A few issues back, we apprised you of the big press hooha over changes in atmospheric concentrations of the hydroxyl radical OH. MIT's Ronald Prinn and colleagues determined that, after OH levels rose throughout the 1980s, they dropped markedly through the end of the century. Because it's so reactive, hydroxyl is difficult to measure in the atmosphere. In fact, OH is highly reactive with the greenhouse gases including methane, sulfur dioxide, and carbon monoxide, acting to remove those compounds from the atmosphere. Where does the blame lie for causing OH to decline? That's right: Humans.

According to Reuters' coverage of Prinn's paper:

The cause of the fluctuation is unclear, the researchers said. But because the decrease in the global concentration of OH is driven by changes in the northern hemisphere—where most of the world's industrialization and emission of human-made gases takes place—the findings likely stem from manmade rather than natural causes.

The paper, we should note, was published in Science, one of the world's premiere scientific journals. The editors of Science deemed this work to be of such profound importance that, in the first week of May, they released it early on-line, as you may recall, via an outlet called "Sciencexpress" that selects papers whose "timeliness and importance" merit early release. "Additional editorial changes in the text and figures may appear in the print version," they caution.

Evidence for the manmade connection was very clear in the Sciencexpress abstract that appeared a few weeks ago:

Analysis of these observations shows that OH levels in the southern hemisphere are on average about 14±35 percent higher than in the northern hemisphere, and global average OH levels rose 15±22 percent between 1979 and 1989 and then subsequently decreased to levels in 2000 about 10±24 percent below 1979 values.

As we pointed out (WCR, Vol. 6, No. 18, 5/28/01), because of the imprecision of the measurements, that study is meaningless: 14±35 percent translates into a range of +49 percent to –21 percent. In other words, it's not clear if OH levels are higher or lower in the Southern Hemisphere. Furthermore, the authors don't know if global OH levels even rose (the range is +37 percent to –7 percent). That means that the change in OH levels is not statistically different from zero. End of non-story.

Well, apparently Prinn is an avid reader of World Climate Report. The non-"xpress" version of the paper just came out. Aside from the occasional addition of a comma or change in capitalization and a slight rearrangement of a few sentences in the conclusion, the papers are identical—with one exception. Here's the new abstract:

Analysis of these observations shows that global OH levels were growing between 1978 and 1988, but the growth rate was decreasing at a rate of 0.23±0.18% year–2, so that OH levels began declining after 1988. Overall, the global average OH trend between 1978 and 2000 was –0.64±0.60% year–1.

Bingo! Statistical significance! Instead of talking about the nonsignificant differences between hemispheres, they now focus on the rate of change of the global OH trend. Suddenly, something that only one month ago was evidence that humans are defiling the atmosphere now is no longer abstract-worthy—instead, it's relegated to the body of the text, where it will remain forever hidden.

The body of the paper is, for all practical purposes, identical between the two versions. The science is the same. The analysis is the same. But the non–statistically significant OH rise from 1979 to 1989 (15±22 percent) and decline from 1989 to 2000 (10±24 percent) is now a significant overall decline of –0.64±0.60 percent per year.

This time, the New York Times got it right. In their May 4 coverage of the Sciencexpress release, reporter Andrew Revkin noted:

Experts in atmospheric chemistry who were not involved in the study...emphasized the difficulties in measuring something that comes and goes so quickly and varies mile by mile. Dr. Ralph J. Cicerone, an atmospheric chemist and chancellor of the University of California at Irvine, said he doubted there was a way to confirm that the hydroxyl radicals were exhibiting wide swings.

Detecting the wide swings in the paper's abstract was far easier.


Prinn, R.G., et al., 2001. Evidence for substantial variations of atmospheric hydroxyl radicals in the past two decades, Science, 292, 1882–1888.


Warning: GCM at Large!

There's a reason those TV psychics run a banner across their ads that says, "For entertainment purposes only." They know their predictions are hardly the basis for making major life decisions. Most so-called psychics can't accurately "read" your past or present, so you'd hardly trust them to predict your future, right? The same is true for the general circulation models.

So we've thought for years that GCM output should come with a warning label attached. Finally, an Australian science agency (or at least its legal advisors) has admitted what we've known for a long time. CSIRO, in a spiffy little brochure entitled "Climate Change: Projections for Australia," leads the reader through the usual laundry list of global warming rhetoric: Rising sea levels, temperatures, number of days with extreme summer temperatures, and so on.

The brochure closes with the following disclaimer:

The projections are based on results from computer models that involve simplifications of real physical processes that are not fully understood. Accordingly, no responsibility will be accepted by CSIRO for the accuracy of the projections inferred from this brochure or for any person's interpretations, deductions, conclusions or actions in reliance on this information.

Given that global warming alarmists have virtually nothing to support their cause except these models, there is really no climate change debate without them. We therefore propose the following warning label for all future GCM propaganda:

This climate model is to be used for political purposes only. Its creators are not responsible for any scientific inferences made from the data, nor is model output designed for comparisons with actual observations under any circumstances. Output from this model may be compared only with output from other models. This model is incapable of simulating tropical storms, El Niños, La Niñas, clouds, thunderstorms, cyclones, anticyclones, fronts, or other natural phenomena responsible for the earth's climate. Inferences about these factors are permissible, however, to the extent that they support the stated primary goal.


CSIRO, Climate change: Projections for Australia, 2001, 8pp. (www.dar.csiro.au/publications/projections2001.pdf)