Eyeballing and other nonsense

Over at Skeptical Science — a must read for those interested in sound explanations of climate science — John Cook has posted an analysis and refutation of an American Thinker article by Gary Thompson.

Let’s look briefly at Gary Thompson’s article, The AGW Smoking Gun.  First of all, note the title. Every skeptic and denier and contrarian out there wants to find that “smoking gun” so they can dismiss AGW. Fair enough. That’s part of science — trying to knock down research and theory.  There have been many attempts both in the past and recently to do so. Climategate has provided  a lot of talking points and has succeeded in raising public, if unfounded doubt, about AGW.

So far, nothing I have seen has been convincing. Pretty much everything skeptics have thrown up has been refuted and Skeptical Science is the place to go for all the dirt.

What is Thompson’s article claiming?

A key component of the scientific argument for anthropogenic global warming (AGW) has been disproven. The results are hiding in plain sight in peer-reviewed journals.

Of course, this assumes that every climate scientist and, in fact, every non-climate scientist who has read the articles he cites are really really stupid since the smoking gun is right there in front of them, smoking away. That, or they’re lying.

Here’s his argument:

The science behind the AGW hypothesis is that increased amounts of CO₂ in the atmosphere (that humans produce by burning fossil fuels) will block more outgoing long-wave IR radiation (OLR) from exiting the atmosphere and thereby warm the surface. It is well-known that IR radiation causes CO₂ molecules to vibrate, but only at very specific wavelengths (wavelengths are the distances between peaks of each wave), and that wavelength is 15µm. (Fifteen µm means that each wavelength crests at a distance of 15 millionths of a meter.) As was discussed above, this vibration of the molecule causes it to heat and then radiate IR radiation back toward the atmosphere and the surface of the Earth. If the solar activity is taken to remain constant, more CO₂ in the atmosphere will trap more of the OLR, and thus cause a net heating of the planet. [my emphasis]

So what type of experiment could be performed to test this AGW hypothesis? If there were satellites in orbit monitoring the emission of OLR over time at the same location, then OLR could be measured in a very controlled manner. If, over time, the emission of OLR in the wavelengths that CO₂ absorbs decreases over time, then that would prove the AGW hypothesis (i.e., that OLR is being absorbed by CO₂ and heating the planet instead of being emitted from the atmosphere). But what if, over time (say, over thirty years), the emissions of OLR wavelengths that CO₂ absorb remained constant? That would disprove the hypothesis and put the AGW argument to bed.

He concludes the following:

The last two graphs can be placed on top of each other, and the black lines (actual measured data) are basically copies of each other. That means that there was no difference in OLR between 1970 and 2006.

All three of the links referenced here devote the latter sections of the papers to removing the impact of surface temperatures and water vapor and graphing the OLR that is associated only with trace GHGs. The authors perform this trick (there is that word again…) based on the climate models and not through actual measurements, and surprise, surprise — these simulated results show a reduction in OLR emission with wavelengths that are absorbed by CO₂. Computer-simulated results based on climate models are never a replacement for actual measured data, and they should never be used to draw conclusions when actual measured data contradicts those models.

So the results of three different peer-reviewed papers show that over a period of 36 years, there is no reduction of OLR emissions in wavelengths that CO₂ absorb. Therefore, the AGW hypothesis is disproven. [my emphasis]

Simple, right?  AGW theory predicts X and models predict X and observations do not show X — hence theory is disproved.

More like simply ridiculous.

Here’s Cook:

Thompson concludes “After analyzing this graph, the following conclusion can be drawn: The 1997 OLR associated with CO2 is identical to that in 1970”. By “analyzing this graph”, he presumably means eyeballing the graph as he provides no actual data analysis. This is a shame because in Harries 2001 directly below this graph is data analysis of the calculated difference between the IMG and IRIS satellite data as well as a comparison with modelled results. What do models predict will happen with rising greenhouse gases? Less longwave radiation will escape at the absorptive wavelengths of greenhouse gases such as carbon dioxide and methane. As the atmosphere warms, it will emit more radiation over the whole longwave spectrum. So we expect to see an increase in outgoing radiation over some of the longwave spectrum with sharp drops at certain wavelengths. This is indeed what is observed, consistent with model simulations.

What’s interesting is that the models of what is expected to happen due to AGW on OLR is almost identical to the measured OLR.

The top curve in Figure 2 is the observed difference between 1970 and 1996 over the central Pacific. This shows strong agreement with the middle curve which is the modelled results. The bottom curve is the observed difference for a near-global area. Observations are consistent with our theoretical expectations of how the greenhouse effect should behave. The close match between observation and simulation lead the paper’s authors to conclude “Our results provide direct experimental evidence for a significant increase in the Earth’s greenhouse effect that is consistent with concerns over radiative forcing of climate”. One wonders how Gary Thompson missed this conclusion as it’s stated both in the paper’s abstract and in the concluding paragraph.

In other words, the theory predicted X and the models predicted X  and satellite observations show X (where X = more long wave radiation at certain wavelengths and less at CO2, methane and other GHG wavelengths)

Let’s look a little more closely at Harries et al:

Here’s Harries:

The bottom panel shows the difference of 1997 minus 1970.  In most places the difference is small, but in some wavenumber intervals the 1997 brightness temperatures are significantly less in 1997.  This reflects the increase in the concentrations of gases such as CO2, CFC and CH4 between 1970 and 1997.  The optical depth depends on the density of the absorber.  If the amount (density, mixing ratio) of absorber increases, the optical depth at the wavelengths of absorption increases, the emission that escapes comes from higher in the atmosphere, where the density is lower and the temperature is lower, and so the brightness temperature is less.  Thus we see the greenhouse gases increases reflected in the emission spectrum of longwave radiation.

The basic principle, as I understand it — more  GHGs such as CO2 and methane in the atmosphere, less OLR in those particular wavelengths.

Here’s the actual abstract from the Harries et al. article in Nature:

The evolution of the Earth’s climate has been extensively studied^{1, 2}, and a strong link between increases in surface temperatures and greenhouse gases has been established^{3, 4}. But this relationship is complicated by several feedback processes—most importantly the hydrological cycle—that are not well understood^{5, 6, 7}. Changes in the Earth’s greenhouse effect can be detected from variations in the spectrum of outgoing longwave radiation^{8, 9, 10}, which is a measure of how the Earth cools to space and carries the imprint of the gases that are responsible for the greenhouse effect^{11, 12, 13}. Here we analyse the difference between the spectra of the outgoing longwave radiation of the Earth as measured by orbiting spacecraft in 1970 and 1997. We find differences in the spectra that point to long-term changes in atmospheric CH₄, CO₂ and O₃ as well as CFC-11 and CFC-12. Our results provide direct experimental evidence for a significant increase in the Earth’s greenhouse effect that is consistent with concerns over radiative forcing of climate. [my emphasis]

In other words, Thompson has not actually analyzed the data — he’s eyeballed the graphs, and maybe even then, did so very badly. There is some doubt whether he really read the papers, for how else he would have come to conclusions that directly contradicts the stated conclusions of the authors?

Thompson shows up at Skeptical Science and responds:

First off, I never stated in the article that I was disproving the greenhouse effect. My aim was to disprove the AGW hypothesis as I stated in the article “increased emission of CO2 into the atmosphere (by humans) is causing the Earth to warm at such a rate that it threatens our survival.” I think I made it clear in the article that the greenhouse effect is not only real but vital for our planet (since we’d be much cooler than we are now if it didn’t exist).[my emphasis]

Hmm. How could Skeptical Science and the rest of us get it so wrong?

Let me repost what he claimed in his article:

A key component of the scientific argument for anthropogenic global warming (AGW) has been disproven. The results are hiding in plain sight in peer-reviewed journals.

Politicians and scientists still cling to the same hypothesis: Increased emission of CO₂ into the atmosphere (by humans) is causing the Earth to warm at such a rate that it threatens our survival. The reality of our global temperatures, the failure of these catastrophic predictions to materialize, and the IPCC scandals all continue to cast serious doubt on that hypothesis. [my emphasis]

So what type of experiment could be performed to test this AGW hypothesis? If there were satellites in orbit monitoring the emission of OLR over time at the same location, then OLR could be measured in a very controlled manner. If, over time, the emission of OLR in the wavelengths that CO₂ absorbs decreases over time, then that would prove the AGW hypothesis (i.e., that OLR is being absorbed by CO₂ and heating the planet instead of being emitted from the atmosphere). But what if, over time (say, over thirty years), the emissions of OLR wavelengths that CO₂ absorb remained constant? That would disprove the hypothesis and put the AGW argument to bed.

Here is his conclusion:

So the results of three different peer-reviewed papers show that over a period of 36 years, there is no reduction of OLR emissions in wavelengths that CO₂ absorb. Therefore, the AGW hypothesis is disproven.

Of course, he’s done nothing of the sort.  What he has done is:

1. Misread the journal articles he cites

2. Failed to support even his own flawed hypothesis

The journal articles he cites found the opposite of what he claimed so he misread them and misrepresented them, either through ignorance or intention.

Worth repeating: The journal articles FOUND THE OPPOSITE!

Second, the AGW “hypothesis” — whatever that is — does not state that the CO2 being emitted since 1970 itself will cause warming at such a rate as to threaten human survival. Many scientists do argue that, based on models scenarios, if this rate of CO2 emission continues unabated, eventually, the warming that results will disrupt the climate and lead to a number of negative effects, including melting of glaciers and ice caps (over the long term), increase in sea level, increased severe weather including droughts and floods, etc.

His little misadventure proved nothing of the sort.

He created a straw man — “the AGW hypothesis” — and then misrepresented the science he misunderstood in a failed effort to disprove it!

American Thinker — and Thompson — obviously need a bit of work in the ‘thinking’ department…