Saturday, March 14, 2009

Troposhpere Temps from Satellites and Surface Temps

In an earlier post I took at look at MM07 versus S09. One of the interesting results was that the rate of post secondary education (PSE) in a country was inversely proportional to the rate of temperature increase in that country. Taking a deeper look I saw that if you take the top quartile of grid points based on PSE from the analysis that the surface warmed more slowly than the troposphere, while in the rest of the grid points the surface warmed much faster than the troposphere. (This is using HadCRUT for the surface and RSS for the troposphere.) I suppose you could shrug this off to coincidence except that according to the Model E data supplied by Dr. Schmidt the troposhpere is supposed to be generally warming faster than the surface everywhere.

Over the 440 grid cells of the analysis the Model E troposphere warmed faster than the surface (.16 degrees per decade versus .14) This contrasts with the measured data from HadCRUT and RSS where the surface warmed faster than the troposphere (.27 versus .23).

Looking at the segment with high PSE we can start with the US. Now I know there has been a lot of sniping about the US temperature network, but I'm guessing that it is really pretty good. Out of the 440 grid points 52 are in the US. For the these grid points the troposhpere is warming faster than the surface (.26 versus .24). There are 85 grid points in the top quartile outside the US. For those points the troposphere is also warming faster than the surface (.21 versus .19).

Now the truth is that this data is very convenient for me to look at because it was already layed out by others, and I haven't looked at any other time periods to confirm that this isn't some kind of fluke.

But I think it is pretty interesting that in the countries that probably have the best surface temperature networks the actual measurements are in line with the theory as proposed by the results of Model E. The conclusion would be that perhaps climate scientists ought to be focused on troposhperic temperatures as measured by satellite, and reduce their dependence on ground based measurements. Switching to satellite measurement seems to be happening elsewhere with a good example being sea level rise.

I should add that they ought to be noticing this type of agreement with models and be pleased with the vindication, but I don't sense that they are. I have a theory as to why.

When the satellite temperatures were first introduced by UAH they were used by climate skeptics to show that there was no warming. In addition Drs. Christy and Spencer aligned themselves to some degree with the skeptics camp. Even though subsequent events have corrected the satellite trends and there now is an independent satelitte measurement from RSS this seems to have put satellite measurements out of favor in this area. This is particularly true for the UAH data.

In fact you can get a hint of this from S09. At one point Dr. Schmidt comments that the differing regression results he got by using RSS versus UAH might be caused by the "higher trend" in RSS. In fact this is uncited and he provides no results to back this up. I think he just assumed it was true, because a quick test of the trends show that for this set of grid cells over this period RSS and UAH have identical average trends. The point being that Dr. Schmidt believed so strongly that of course UAH would show less warming than RSS that he didn't even test the conclusion.

I think it would be quite interesting if the climate modeling community would look at their results relative to the troposhperic measurements from RSS/UAH and deemphasize the surface network. There is plenty of warming in the satellite measurements, and they may be a whole lot more accurate


  1. Many good points.

    But I'm not such a fan of your analysis using PSE. MM07 analyzed many variables. Isn't it inevitable that one or more of those variables would show "interesting" results. Based on what you describe here, it seems like the default assumption should be that the correlation is spurious.

  2. Hasn't Schmidt's recent position been that a faster warming troposphere is a characteristic of warming in general rather than AGW in specific ?

  3. Anonymous, yes I understand your point about PSE and cherry picking. But it turns out that the US is a separate way to look at the split. It is my belief that the US ground based temperature network, particularly with GISS adjustments is probably the best in the world. In this case measurement matches theory as it does in the other locations with high PSE.

    So theory says that the troposphere should warm more quickly. In the area that has the best measurement system this is happening. There are reasons beyond random selection of variables to think that this makes sense.

  4. Other Anonymous. Yes I believe the the troposphere should probably warm more quickly regardless of the source of the forcing. My theory has nothing to do with AGW, it is just about the measurement systems.

    Theory and observation would seem to indicate that ground based measurements might be overstated.

    Remember that all of this is only over land which makes up a minority of the total global measurement.