Earlier I pointed out the multiple errors of thinking in Oregon's Chuck Wiese's claim that the horrendous heat wave we had here in the Pacific NW at the end of June -- an unbelievable 117°F in Salem, Oregon, a maximum reading that was a full 39°F above the normal for that day (normal period = 1981-2010) -- was, he claimed, nothing special at all, just a regular heat wave with the sun in its sunlike position.
I found another huge error.
Needless to say, actual scientists concluded that anthropogenic climate change had a very significant role in such a huge heat wave anomaly.
Chuck Wiese argued that it was just another heat wave but caused by orbital and solar parameters and a nominal increase in atmospheric CO2, calculated naively -- a claim easily shown to be B.S. by all the factors he chose to ignore.But shortly after, as I was looking more closely at his claims, I saw a deeper error, which I haven't been able to write about since I was busy on an article. He considers atmospheric CO2 to be a blackbody, when it is anything but.
Recall, a "blackbody" is one that absorbs all radiation incident upon it. The Sun is a perfect example. The surface of the Earth is a pretty good example, in the infrared. But atmospheric CO2 does not meet that definition at all.
Let's get into the technical details of Wiese's error.
In his post on Ed Berry's site -- a place Wiese considers "publication," LOLz -- he presents this little argument:
What about atmospheric CO2? In 1981, the Mauna Loa CO2 level was given as 341 ppmv whereas today it is 416 ppmv. Calculating the change in radiative forcing from CO2 as a stand-alone constituent, the difference from 1981 to now is only 1.07 Wm-2. ( Watts per square meter ).This is just comical as physics, and let me show you why -- again, Wiese thinks atmospheric CO2 is a blackbody, which it is certainly is not. Bear with me through a few elementary equations.
Next, I took the mean temperature of the daily temperature delta or deviation, which was about 90 deg F and plugged that into the derivative of the Stefan Boltzmann equation, dF/dT which gives 6.45 Wm-2K-1 or 6.45 Watts per square meter per degree Kelvin.
Using this relationship, if CO2 acts alone as permitted in this special case, we get 0.963 Wm-2 with a ground emissivity of 0.9 divided by the rate of change of flux with respect to temperature or the 6.45 Wm-2K-1 number which gives 0.15 deg C or a possible contribution of +0.27 deg F. to the heating total.
CO2's radiative forcing is, from the "Arrhenius equation"
where alpha is a constant = 5.35 W/m2. From this we can indeed verify that the change in forcing going from CO2=341 ppmv to CO2=416 ppmv is, from the above equation, 1.06 W/m2, just a slight rounding difference from CW's result. OK.
Next Wiese uses the Stefan-Boltzmann law for a blackbody
He takes "the mean temperature of the daily temperature delta or deviation" [???], which he says was about 90 deg F (305 K), and using this third equation to get ΔP/ΔT = 6.46 W/m2. Let's call this "A."
Then here's where Wiese makes his big mistake. He wants to use this result to determine the change in temperature from atmospheric CO2. But atmospheric CO2 isn't a blackbody. A blackbody is defined as one which absorbs all electromagnetic radiation incident upon it. Again, the Sun is a perfect example. Atmospheric CO2 isn't.
Here's an absorption chart from NASA. In regions that matter, CO2 strongly absorbs around 4.3 microns, 9.4 microns, 10.4 microns and 15 microns (not shown). It doesn't absorb much anywhere else.
[In truth the spectrum is a lot more complicated, with hundreds of thousands of absorption lines, but still CO2 does not absorb all outgoing radiation, not by a long shot.]
So atmospheric CO2 isn't a blackbody. Everything Wiese does after this point is junk science. He just proceeds blindly along, mashes a couple of different things together and uses this equation:
Oh boy. Besides the CO2-blackbody problem, here there's a ground emissivity when there should be an atmospheric emissivity, a rather mysterious (to me at least, as defined) 90 F entered into the problem per above, a radiative forcing (forcings are defined at the troposphere) used as the radiance of the CO2-blackbody, not to mention all the other problems I originally laid out about the value of CO2 on that particular day, the other GHGs, the urban heat island effect, dimming pollutants, and.... What a mess!
Of course experts did conclude that this monstrous heat wave did have an anthropogenic component to it. I'm not going to go over that again. It killed about a thousand people. That Chuck Wiese and Lars Larson are trying to downplay and confuse the issue is really shameful, but not really surprising given what we've seen of them in the past.
8 comments:
David, I'm not sure that Wiese is saying that CO2 is a black-body. What he's trying to do is assume that the Earth's response to the CO2 forcing is close to blackbody, not that CO2 is a blackbody. He is simply calculating the non-feedback Planck response to CO2, but getting it wrong. It's at the atmospheric skin layer that the radiation in equals the radiation out because convective heat and latent heat are negligible. Fourier knew this 200 years ago. At this layer the outgoing infrared has to be ~ 240 w/m^2, which corresponds to a temperature of 255 K. Not the 305 K that he's using (I have no idea where he gets this either). Of course, by calculating the Planck response and getting it wrong, he's also neglecting feedbacks on the system. Even the emissivity is in the wrong place --- it should be in the denominator, not the numerator (but that's the least of the problem).
The rest of the argument doesn't make any sense. Yes, solar insolation peaks in June, but as we all know thermal inertia due to the oceans means that temperatures in the northern hemisphere peak in August or so. He's not solving a full energy balance equation on the surface which does include convection and latent heat. Rather, he's assuming only radiation balance for the surface --- which is absurd, especially for a meteorologist. He doesn't even factor in the albedo from what I can see. If only solar insolation in June mattered for Portland, why don't temperatures always peak in June?
Hi Joe. Thanks for your comment. I went out of town and am taking some days off so it's might take me some days to get back to you on this. But I will....
Hi Joe. I have a few minutes.... I admit to being very confused by Wiese's argument. The only way I was able to reproduce his number of 0.15 C was to use his radiative forcing number of 1.07 W/m2, which is of course radiation coming down from the atmosphere. That's why I thought he was assuming that atmospheric CO2 was a blackbody.
But, similarly to you, his calculation seems to me so mixed up that it's almost hopeless -- to me anyway -- to understand what he's doing.
Hi David,
I find it useful to think of the radiative forcing, not as radiation coming down from the atmosphere, but as radiative flux that is missing from the Earth's outgoing infrared. David Archer's on-line modtran model is useful for exactly this problem. You can find it here: http://climatemodels.uchicago.edu/modtran/
Keep the altitude at 70 km, looking down. I usually use the 1976 US standard atmosphere. Set the CO2 concentration to zero and note the outgoing integrated upward IR heat flux. Then plot the heat flux for values, 2, 50, 200, 300 .... 1000 or so. If you plot the outgoing flux as a function of CO2 concentration, you'll see that it looks very similar to Myrhe's formula that you have as Equation 1 (or rather plot the negative of Myrhe's formula alongside the modtran result). You'll have also demonstrated for yourself the band saturation effect that is responsible for the logarithmic dependence on CO2 concentration.
For a doubling of CO2, Myrhe's equation gives 3.71 watts/m^2. From your equation (3), one can get that the Planck response (without feedbacks) gives a delta-T = 0.27 K/(w/m^2) * delta-P (I dropped the emissivity and used T = 255 K at the skin layer). That means the delta-T for a doubling of CO2 is about 1 K without feedbacks.
This is more-or-less what Wiese is doing but Wiese is going from 341 to 416 ppm CO2 and using 305 K instead of 255 K for the Planck response.
Hi Joe. I emailed Chuck Wiese and Ed Berry a link to our comments, and here's what I got back:
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There are no errors in my calculations, Appell, and you are so screwed up in your misrepresentations of what I state, there is no hope you will ever recover from your idiocy. You have the comprehension of a ten year old because you aren't interested in science. You distort it rather than use it.
You can't seem to get it through that thick skull of yours that I have never called atmospheric CO2 a black body. I have stated that the 15 micron band which composes the Q-branch of its radiation behaves nearly as a black body over that narrow range of wavelength where the absorption coefficients are very high similar to black body radiation. Elsasser's treatment of CO2 uses this premise and it is perfectly valid.
The forcing equation you used is precisely the one that I used to compute the CHANGE in radiative forcing as integrated over CO2's wavelengths from increasing atmospheric CO2.
Being the scientific moron you keep demonstrating that you are, you claim that I applied this result to black body radiation emission FROM ATMOSPHERIC CO2 which you erroneously call a mistake, because apparently, you think the earth's surface is not a Planck emitter, which it clearly is with a ground emissivity of roughly .9.
That is where the calculation follows through with a plug-in to the Stefan Boltzman equation that emits this absorbed radiation from the earth's surface. If it is emitting from the earth's surface as it would be in this special case, this CHANGE in radiative forcing from the Arrhenius relationship is most certainly valid in the Stefan Boltzman equation.
The number of times that you continue to make a fool out of yourself with your distorted and wrong assertions seems to know no bounds. You are not worth the time of day for me to go over to your blog that nobody reads to argue science with someone who distorts and argues nonsense.
Chuck Wiese
Meteorologist
Pleasant fellow.
Yes, very pleasant fellow. And so illuminating.
Hi guys. I'm back home and just got some work, but will get back to this as soon as I can.
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