global climate change

Stratospheric Temperatures: Bleg.

32 Comments

I haven’t taken any “pre-peeks”, but it occurred to me that, since Global Warming predicts surface warming with stratospheric cooling, it might be useful if I also run tests on the stratosphere. I found the NOAA page with
MSU and RSS data.

As I’d like to look at as much data as possible and compare to stated hypothesis I was hoping some might direct me to:

  1. Any other sources of data for recent time periods. (2001-now is essential. Earlier is nice.)
  2. Any projection/ predictions. (Otherwise, I will just test 0C/Century and state betas as we go along.)
  3. An literature discussing past evaluations of this data. (My impression is the stratospheric cooling is not anticipated if warming is due to solar. So, this seems a good compliment given JohnV’s recent suggestion to consider the solar connection when hypothesis testing.)

Thanks!

32 thoughts on “Stratospheric Temperatures: Bleg.”

  2. Moshpit presents:

    a cage match. Lumpy versus ModelE.

    Simple versus complex.

    What gain in accuracy is there?

    Lumpy hindcast versus ModelE hindcast.

    lumpy forecast versus modelE forecast. Time capsule test.

  5. So we ought to get absolute cooling at between 40-50 km, and we should also get relative troposphere warming: the tropical troposphere, somewhere around 5km, should warm faster than the ground? Is that right?

    When I raised this question a while ago on Tamino, the general view seemed to be that we should not expect the relative warming, it was not predicted by the IPCC, and its absence would not falsify GG warming, and therefore Ross McKittrick’s tax proposal was pointless. Never did grasp why all this exactly. And a quick look at IPCC suggested the tropical warming was indeed predicted. But we should apparently expect the stratospheric cooling, and it was happening, was what most people said. No longer read Tamino, so it may have changed.

    It would be great to have a definitive view of what exact developments in the atmosphere would falsify GG warming, were it to happen. Glad to see you turning your attention to this.

  6. fred–
    I’m not too surprised to read Tamino suggesting the IPCC didn’t predict relative warming, and yet one might read the IPCC to predict that.

    As far as honest to goodness projections/predictions that can be pinned down, the IPCC doesn’t come out and post much that can be tested. On the one hand, this is likely due to the fact that there is a lot of work involved in any particular prediction/projection. But on the other hand, it makes evaluating the skill of the predictions a bit like evaluating the accuracy of Jean Dixon or Nostradamus. If the “prediction/projections” are sufficiently vague, how can we test if they were correct? In so far as they are vague, they often cannot be wrong. On the other hand, to the extent they are too vague to even pin down the temperature in 1990 when writing a document in 2001, I think we all have a right to complain that we don’t believe there are any true post-prediction verifications or evaluations of skillfulness!

    So, for my part, I’m going to find what statements I can, interpret them, and compare to data. My theory is that by going ahead and doing it publically, having people read what I post, we may influence the upcoming fifth report be somewhat clearer (or not.)

  7. And then you have “cherry picking” after the fact. Tout the results that support your prediction and ignore those that don’t. I think it was Parade magazine (a Sunday supplement in our paper) that used to publish Dixon’s predictions, but I don’t ever remember them pointing out how bad her batting average was even allowing for the vagueness of some of them.

    One thing about the modelers that troubles me is that they believe their results when they appear correct and ignore those that don’t. How do you know that the matching of the model to the real world wasn’t just random luck? Similar scenario to those touting stock market predictors.

  10. Boris, it is incorrect to state that

    any warming should be somewhat greater in the tropical troposphere–whether it’s solar, GHG or whatever.

    Because the modelers would disagree with you.

    Looking at the image here:

    Solar heats the atmosphere fairly uniformly, with no “hot spot” (mind you, this is TSI (and UV-Ozone?)).

    Now, I don’t want to get flamed by linking to the analysis of the evil Steve Milloy but…

    All is not well in the stratosphere…

    BTW, ongoing discussion of tropical trends at climate audit, where Christy has chimed in about the RC critique of Douglass et al.
    http://www.climateaudit.org/?p=3048

    Admin note:You won’t be flamed for linking to Steve Milloy; I try to prohibit all flaming. Also, I permit linking to nearly anything. My inclination is that it’s better for people to be specific and linkboth when discussing topics whether they agree or disagree with them.

  11. David,

    Real Climate had a good response to that, I thought. But anyway it wouldn’t disprove warming by GHGs, but our understanding of lapse rate, because any warming should be somewhat greater in the tropical troposphere–whether it’s solar, GHG or whatever.

    However, stratospheric cooling is the fingerprint of GHG warming. But ozone depletion is confounding that signal somewhat.

  13. Boris, re: “However, stratospheric cooling is the fingerprint of GHG warming.”

    I was under the impression that the majority of stratospheric cooling was hypothesized to be due to increased stratospheric H20?

    —

    Lucia, Happy (slightly belated) Bday, and here are a couple of references wrt your #3: (I’ve no idea if they’ve been superseded)
    http://pubs.giss.nasa.gov/abstracts/2001/Oinas_etal.html
    http://pubs.giss.nasa.gov/abstracts/2001/Shindell.html
    and an overview of that second paper here:
    http://www.giss.nasa.gov/research/briefs/shindell_05/

    Great blog by the way.

  14. Andrew,

    See RC’s post here:

    http://www.realclimate.org/index.php/archives/2007/12/tropical-troposphere-trends/

    The basis of the issue is that models produce an enhanced warming in the tropical troposphere when there is warming at the surface. This is true enough. Whether the warming is from greenhouse gases, El Nino’s, or solar forcing, trends aloft are enhanced. For instance, the GISS model equilibrium runs with 2xCO2 or a 2% increase in solar forcing both show a maximum around 20N to 20S around 300mb (10 km):

    The first thing to note about the two pictures is how similar they are. They both have the same enhancement in the tropics and similar amplification in the Arctic. They differ most clearly in the stratosphere (the part above 100mb) where CO2 causes cooling while solar causes warming. It’s important to note however, that these are long-term equilibrium results and therefore don’t tell you anything about the signal-to-noise ratio for any particular time period or with any particular forcings.

    If the pictures are very similar despite the different forcings that implies that the pattern really has nothing to do with greenhouse gas changes, but is a more fundamental response to warming (however caused). Indeed, there is a clear physical reason why this is the case – the increase in water vapour as surface air temperature rises causes a change in the moist-adiabatic lapse rate (the decrease of temperature with height) such that the surface to mid-tropospheric gradient decreases with increasing temperature (i.e. it warms faster aloft). This is something seen in many observations and over many timescales, and is not something to climate models.

    In addition to not trusting Milloy, I would not trust Monckton or SPP either. BTW, I could make neither heads nor tails out of the image you linked.

    I just posted over at CA. Maybe someone has a reliable source…

  16. (I’m cross posting this from CA)
    Andrew,

    Ah, I see what’s wrong with Monckton’s interpretation of the figure you cite.

    The figure shows the contributions from the various forcings, and then the total effect of all forcings combined. It does not attempt to show various forcing fingerprints.

    Here is the actual caption from the figure Monckton uses:

    Zonal mean atmospheric temperature change from 1890 to 1999 (°C per century) as simulated by the PCM model from (a) solar forcing, (b) volcanoes, (c) wellmixed greenhouse gases, (d) tropospheric and stratospheric ozone changes, (e) direct sulphate aerosol forcing and (f) the sum of all forcings

    As you can see, this has nothing to do with “fingerprints” or “signatures.”

  17. Lucia and others, I’d be interested as well in any links to digital projections of T4 or T2LT under doubled CO2. I trust that someone somewhere has filed projections that tie into what is actually reported in the primary observations.

  18. The problem the people at NASA Goddard are running into is that although they had meant for their model projections to be “unfalsifiable” at least to the middle of this century, clever statistical techniques used by Lucia, William Briggs, etc. are able to falsify the models’ projections much earlier.

    So they are reduced to the type of verbal dancing that you see in comment 2317 above. Not dignified for a NASA scientist, but one does what one must.

  19. Pingback: Niche Modeling » Douglass et al 2007 and Atmospheric Models

  20. Hi Boris, I don’t have time to get into the stats on RC right now. However, see the post above. Your second point also seems correct, that ozone confounds stratospheric cooling is simply not inconsistent with troposphere warming, not a ‘fingerprint’ of GHG warming, if by fingerprint you mean a unique pattern that identifies something. Regards

  22. Oh. steve. they have an utterly retarded naming convention for scenarios so caveat emptor.

  23. How would one determine from running models that a particular phenomema was a FINGERPRINT.
    fingerprint of the world or fingerprint of the model. Predicted phenomena or computational
    artifact?

    I’m getting very sceptical about this fingerprint metaphor. decompose the fingerprint metaphor into maths.

  24. The fingerprint of eqns in GCMs in maths is something like:

    delta surf temps prop delta IR prop delta optical depth prop delta GHG concentation – greenhouse increasing.

    The fingerprint of eqns in the smi-transparent theory is something like:

    delta surf temps prop delta IR atmosphere down inv prop delta IR top of atmosphere up – greenhouse constant.

    If any of that makes sense.

  25. I’m going through that latter paper you mentioned on your site. My head hurst. Opps a fractal joke. my head hurts.

    In any case, the fingerprint of AGW is asserted by the models. That is, the models say, if you have AGW, then
    you will see this fingerprint.

    When allegeded fingerprint is slow to show, they say. wait a few years. After a while of no show, they say,
    the models while largely correct need adjustment in this area.
    Crap, guys, raise your hand if you danced this kind of dance before. everybody? ya I thought so.

    Modelers Anonymous.

  28. Steve,
    Step 1. Deny, Step 2. apply auxilliary hypotheses, Step 3. Claim the credit yourself. Read about the way Tommy Gold and others have been treated by establishment scientists. Very predictable.

  29. Andrew,

    Your graph is for the lower strat, where ozone dominates. CO2’s cooling effect is greatest at the top of the strat. –40-50km.

    See the graphs at the bottom of this page, though they are a decade out of date. Anybody know of any updated upper stratospheric temps?

    http://www.atmosphere.mpg.de/enid/20c.html

  30. Thanks, unfortunately the sources I’m using only seem to have lower stratosphere temps. Hm…Now where would one find upper stratosphere data…I’m off to searching!

  31. Stratospheric cooling observed since 1992 is the result of less aerosols in the upper troposphere / lower stratosphere. The role of aerosols is the achilles heel of climate models. The lack of aerosols in the atmosphere explains the twin effect of cooler stratosphere temperatures and warmer surface temperatures since the mid-90’s (particularly if coupled with a more active sun). In fact, it is a better explanation of the observed warming than CO2-driven positve feedback loops. The fact that there was no mention of the role of aerosols in the posts above (and in other similar threads) suggests to me a certain amount of ignorance on the subject by the posters. By the way, I claim no expertise on the matter, it’s just that no one else seems to understand what is going on. For goodness sake, there’s no consensus on its sign (i.e., positive or negative) or whether aerosols are increasing or decreasing. I’ve been scouring the net for the past two months on the subject and there is literally no consensus on the matter. Most assume aerosols have gotten worse. The air over NH (North America, Europe, and Asia) has probably never been cleaner in 100 years due to modernization of China, collapse of the Former Soviet Union, and uber pollution control equipment installed in Europe and America. Based on info summary results that I’ve seen, ALL of the supposed warming by CO2-driven feedback loops can be negated by the effect of aerosols (not in the traditional sense where more aerosols mask CO2-driven global warming, but in the counter-intuitive sense that less aerosols cause surface heating and therefore should cause a decrease in the influence of CO2 in the climate models).

  32. Boris, hee is my take on the stats at RC.

    An easy way to understand the issue is to ask “What random data would I need to generate to pass a particular test?”

    For the test proposed at RC, I would only need to generate radom data with sufficient variance to encompass the observations, irrespective of the mean.

    For the test in Douglass, I would need to generate data where the mean matched the observations. To do this I would need the random number generating process to be sufficiently right about physical reality to reproduce the lapse rate change. This matches the intent of the Douglass comparison.

    RC slides over the issue that they are not looking at the possible trajectories of temperature over time, but at the atmospheric profile aloft. This is much more constrainted that the time-evolution of the system, and much more theory laden. Thats why it is a test of the theoretical basis of the models (which they fail).

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