Sherwood, Allen, and radiosondes

The media recently wrote far-reaching comments about the latest Nature Geophysics article by Steven Sherwood and Robert Allen (Yale University):
Warming maximum in the tropical upper troposphere deduced from thermal winds.
The authors – or at least the media – have claimed that a new method to “measure” the tropical tropospheric temperatures has removed all contradictions between the theoretical and empirical warming rates in the troposphere.

Recall that the greenhouse-dominated models predict rapid warming in the troposphere, roughly 10 km above the equator. The satellite measurements (UAH MSU, RSS MSU) show an actual warming rate that is at least 10 times slower than the theoretical predictions. The data from balloons and radiosondes they carry, for example the Hadley Center data, confirm the satellite figures. Detailed numbers will be discussed below.

That seems to be a problem. Every acceptable solution to this problem must either find serious errors in both the satellite and balloon data or a serious error in the theoretical models (or both).

Steven Sherwood and his pre-PhD student, Robert Allen, use a different strategy. They pretend that the discrepancy doesn’t exist at all. How do they do it? Well, they want you to believe that the measurements of the temperatures don’t exist. Instead, they propose their own, idiosyncratic, elaborated “measurement” of the tropospheric temperatures. Well, there is one additional immediate problem: it’s not really their own method, as we will see. 😉

Sherwood & Allen vs Pielke Sr

They look at some patterns in the thermal (?) westerly winds, manipulate them to obtain a rather continuous function, and claim that this function of the winds data is … a measurement of temperature that is apparently better than the thermometers. Their method is not really original: it is a small subset of the methods discussed by Roger Pielke Sr and two co-authors in 2006 and especially by Pielke Sr and four co-authors in 2001. See also Pielke’s comments about his priority.

So the idea is that instead of proving global warming, you prove global blowing 🙂 and then you argue that blowing and warming sound similar, especially according to your model that links the two. This strategy has the advantage that when the climate begins to cool down, you can also say that global blowing is the same thing as global cooling and the cataclysmic warming can continuously “rotate” into a new kind of catastrophic cooling. 🙂

The problems with the particular conclusions by Sherwood and Allen have been discussed by
Roger Pielke Sr,
too. He is preparing a technical manuscript on that issue. The main drawback of their approach is circular reasoning. They want to demonstrate that the models are consistent with reality but what they actually call “reality” is extracted from the models, too.

More precisely, the relationship between the winds and the temperature is derived from the very same models that are shown to disagree with the actual temperature measurements by the balloons and satellites. So the arguments they show only support the compatibility of one particular theoretical prediction with the observations – namely the quantity describing winds as predicted by the very same models.

But a correct model should agree not only with one but with all observed quantities – especially with the temperature if this quantity is the main focus of your models. 😉

The models also link this quantity related to winds to the temperature but the real measurements actually falsify the predicted temperature trend and the Yale authors don’t change anything about that. To a large extent, they only demonstrate a “self-consistency” – which really means uniqueness of one prediction by the models that characterize the winds. It is not shocking that the predictions of such a model are self-consistent; it is much more non-trivial constraint that they should also be consistent with the real data.