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Is Kirchhoff’s rule in atmosphere proven by the Cabauw measurements, or not? I had earlier received a note on calculations by Noor van Andel claiming, yes, Kirchoff’s relationship as used in Miskolczi’s theory was confirmed by the linear regression of Ed (longwave down radiation) and Su(1-Ta) (longwave surface up, without transmitted longwave). Miskolczi also confirmed this result, using older results in a the previous post in this series.

However, I just received an email from Rob van Dorland who took the actual measurements claiming this is not the case. In Rob’s opinion:

The calculations show “Kirchhoff’s rule” cannot be obtained using my measurements. These measurements consist of downward radiation at the surface and the mixing ratio’s of water vapor at the surface (that is what I sent to Noor van Andel). From this you cannot compute the atmospheric LW transparency (Ta), like Noor van Andel did, because you need information on profiles of temperature, water vapor and of other greenhouse gases. Of course, I used this profile information to compute the downward radiation at the surface and compare these computed values with the observed ones (see attachment).

From Thesis Rob van Dorland, 1999.

I think the computation of Kirchhoff’s rule by Noor illustrates very well that assumptions (which are not a standard part of radiative transfer calculations) are put into the model of Noor (and probably also in Ferenc’s model). In turn these assumptions result to my opinion in wrong conclusions such as the optimum optical depth for the present Earth’s atmosphere and the very low sensitivity to CO2 changes, stated in Ferenc paper.

Rob mentions for background information you can download the pdf of chapter 3 of his thesis. Click on “deel 2″ at the end of this page after the reference to the thesis.

I must admit I thought Noor’s results were based on profile measurements at the 200m high Cabauw tower, near Lopik, the Netherlands. Unfortunately I have been unable to contact Noor to gain his approval to publish the findings on the web.

Update: Rob has sent details of the data and the data itself he sent to Noor. I think it clears up the profile issue, as I (mis)understood Noor’s note to read that he calculated the profiles. The data sent by Rob is here, and email below.

Dear David
See my brief response below
regards
Rob

David Stockwell wrote:

>Dear Rob,

>Thanks very much. It takes a disagreement to provoke discussion on the web, you are right!
>Still I think we learn more in an interesting way when that happens.
>I am interested in your statement that you did not send Noor temperature and water
>vapor profile information, as he says clearly in his note that the calculations of
>Ta are based on profile information sent by you. I am just a bit confused.

Noor only got the surface values. please ask him. I send you the same file as I did in May to Noor.
column 3: 2m temperature
column 4: 2m humidity
column 5: Longwave downward measured at the surface
column 6: Longwave downward calculated at the surface

lwdmeas_calc_van_dorland

>”The 200 m high radio broadcast transmitter in Cabauw, near Lopik, the Netherlands,
>can be used, like a weather balloon, to measure atmosphere profiles,
>albeit only until 200 m high. Rob van Dorland has measured these profiles. ”

I actually combined the 200 m tower measurements with the balloon measurements. So I got profiles of temperature and humidity up til a height of 25 to 30 km. Further details of my comparison can be read in paragraph 3.5 of my thesis.

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