The Search for a Short Term Marker of Long Term Climate Sensitivity
By Dr. Roy Spencer. October 4th, 2009
[This is an update on research progress we have made into determining just how sensitive the climate system is to increasing atmospheric greenhouse gas concentrations.]
While published studies are beginning to suggest that net feedbacks in the climate system could be negative for year-to-year variations (e.g., our 2007 paper, and the new study by Lindzen and Choi, 2009), there remains the question of whether the same can be said of long-term climate sensitivity (and therefore, of the strength of future global warming).
Even if we find observational evidence of an insensitive climate system for year-to-year fluctuations in the climate system, it could be that the system’s long term response to more carbon dioxide is very sensitive. I’m not saying I believe that is the case – I don’t – but it is possible. This question of a potentially large difference in short-term and long-term responses of the climate system has been bothering me for many months.
Significantly, as far as I know, the climate modelers have not yet demonstrated that there is any short-term behavior in their models which is also a good predictor of how much global warming those models project for our future. It needs to be something we can measure, something we can test with real observations. Just because all of the models behave more-or-less like the real climate system does not mean the range of warming they produce encompasses the truth.
For instance, computing feedback parameters (a measure of how much the radiative balance of the Earth changes in response to a temperature change) would be the most obvious test. But I’ve diagnosed feedback parameters from 7- to 10-year subsets of the models’ long-term global warming simulations, and they have virtually no correlation with those models known long-term feedbacks. (I am quite sure I know the reason for this…which is the subject of our JGR paper now being revised…I just don’t know a good way around it).
But I refuse to give up searching. This is because the most important feedbacks in the climate system – clouds and water vapor – have inherently short time scales…minutes for individual clouds, to days or weeks for large regional cloud systems and changes in free-tropospheric water vapor. So, I still believe that there MUST be one or more short term “markers” of long term climate sensitivity.
Well, this past week I think I finally found one. I’m going to be a little evasive about exactly what that marker is because, in this case, the finding is too important to give away to another researcher who will beat me to publishing it (insert smiley here).
What I will say is that the marker ‘index’ is related to how the climate models behave during sudden warming events and the cooling that follows them. In the IPCC climate models, these warming/cooling events typically have time scales of several months, and are self-generated as ‘natural variability’ within the models. (I’m not concerned that I’ve given it away, since the marker is not obvious…as my associate Danny Braswell asked, “What made you think of that?”)
The following plot shows how this ‘mystery index’ is related to the net feedback parameters diagnosed in those 18 climate models by Forster and Taylor (2006). As can be seen, it explains 50% of the variance among the different models. The best I have been able to do up to this point is less than 10% explained variance, which for a sample size of 18 models might as well be zero.
Also plotted is the range of values of this index from 9 years of CERES satellite measurements computed in the same manner as with the models’ output. As can be seen, the satellite data support lower climate sensitivity (larger feedback parameter) than any of the climate models…but not nearly as low as the 6 Watts per sq. meter per degree found for tropical climate variations by us and others.
For a doubling of atmospheric carbon dioxide, the satellite measurements would correspond to about 1.6 to 2.0 deg. C of warming, compared to the 18 IPCC models’ range shown, which corresponds to warming of from about 2.0 to 4.2 deg. C.
The relatively short length of record of our best satellite data (9 years) appears to be the limiting factor in this analysis. The model results shown in the above figure come from 50 years of output from each of the 18 models, while the satellite range of results comes from only 9 years of CERES data (March 2000 through December 2008). The index needs to be computed from as many strong warming events as can be found, because the marker only emerges when a number of them are averaged together.
Despite this drawback, the finding of this short-term marker of long-term climate sensitivity is at least a step in the right direction. I will post progress on this issue as the evidence unfolds. Hopefully, more robust markers can be found that show even a stronger relationship to long-term warming in the models, and which will produce greater confidence when tested with relatively short periods of satellite data.
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Anthony, you spelled Spencer wrong in the by-line.
REPLY: Yeah I’m a dyslexic typist at times, all the letters were there 😉 Thanks
Anthony
AFAIAA, the models don’t include sea sub-surface temperature gradients (and anyway the satellites can’t measure ocean temp gradients), which is where I would look for short term indicators of long term climate trends.
If it’s in the satellite data as well as the models it has to be a real value.
The need to average multiple models stumped me a bit, but I suspect that is a Christie type red herring.
So I plump for changes in the albedo reflective spectrum (oceans? oceans and land?), perhaps relative to the size of the warming event. Which would point to an underlying biological mechanism.
And I’d add, that if the value is found in the climate models, then that is the proper function of the climate models, to indicate where to look for climate relevant values in the real world, and not to make climate predictions.
One of the many salient quotes:
“It needs to be something we can measure, something we can test with real observations. Just because all of the models behave more-or-less like the real climate system does not mean the range of warming they produce encompasses the truth.
Chris
Norfolk, VA, USA
I have no idea what the man is talking about, but I’m guessing the recent jump in satellite measured temperature at the 14,000 foot level that he regularly tracks along with the recent SST numbers has given him pause to reflect. I suspect the “skeptic” community will not be delighted with Spencer’s eventual unveiling of his latest theory.
Perhaps I have the wrong take on this, but let me query in lay terms:
1) A number of climate models exist, no doubt with much commonality in terms of the functional relatioships within them.
2) There is a reasonable correlation between two variables across these models being noted here.
Why should this be surprising? I would almost counter with… I am surprised there is not a stronger correlation.
Have we got to the stage where science is now backwards? We generate models and feed in some data, then come up with an hypothesis? As someone that has studied econometric modelling extensively I find this somewhat disturbing, but perhaps I am getting the gist of this article wrong.
My mystery index candidate is the inverse of sea surface temperature.
Well, this past week I think I finally found one. I’m going to be a little evasive about exactly what that marker is because, in this case, the finding is too important to give away to another researcher who will beat me to publishing it (insert smiley here).
This should not be a concern of any person who is interested in science for the sake of science with the ultimate goal of finding truth. That is my initial reaction to this article. This is before I looked up Dr. Spencer.
Ehh.
Why does it even matter. How can a person who believes that the earth was created by an imaginary being be expected to have an objective view of the natural world and its processes.
NOTE TO READERS: This person has demonstrated all the classic symptoms of trolling, best to just ignore him. – A
Claude Harvey
“I have no idea what the man is talking about, but I’m guessing the recent jump in satellite measured temperature at the 14,000 foot level that he regularly tracks along with the recent SST numbers has given him pause to reflect.”
Why would “recent” changes “give him pause to reflect.” The supposed global warmining didn’t just start “recently”, did it?
danappaloupe
Do you have that same regard for Issac Newton, etc.?
Translation:
Anyone believing in God, gods, Gaia, Cthulhu or the Flying Spaghetti Monster is incapable of performing science a priori.
Tolerance.
REPLY: We aren’t going to have a religious discussion here, best to just ignore him. Troll. -A
Wow, this article went completly over my head. I might possibly have a tiny glimmer of what short term differences impacting long-term results of the models means –I think he’s saying the models are so primitive as to have monotonous increases built into them that are impervious to short-term changes. This would likely be why we hear all that “come back with a vengeance” crap –they literally mean it since they expect it all to average out to their models in the long run, so a period of less now requires a period of more later.
So that much, at least, I *think* I get.
But what that has to do with a marker that would explain the differences between the climate model program results. . . I’m utterly not getting the connection, or how such a thing could be possible, or if it was why it would mean anything other than Dr. Roy has identified the major difference in algorithm *between the models*. Why that might be interesting, I still can’t think of why it would have any real-world applicability in determing how the models *should* change to reflect a short-term change.
But he’s a smart man. I’m sure he has something interesting in mind here –but I’m just not getting it yet. Perhaps having to be coy about what it actually is causes it to be hard to communicate how it ties together. Or perhaps I’m just not that smart. 🙂
danappaloupe (22:36:14) :
Well, this past week I think I finally found one. I’m going to be a little evasive about exactly what that marker is because, in this case, the finding is too important to give away to another researcher who will beat me to publishing it (insert smiley here).
This should not be a concern of any person who is interested in science for the sake of science with the ultimate goal of finding truth. That is my initial reaction to this article. This is before I looked up Dr. Spencer.
Ehh.
Why does it even matter. How can a person who believes that the earth was created by an imaginary being be expected to have an objective view of the natural world and its processes.
Your logical fallacy is called “Poisoning the Well” It does not matter who someone is or what their beliefs are in other fields. What matters is the evidence/data and the conclusions that can be drawn from that data.
The flip side of your “Poisoning the Well” is “Argument from Authority” – I.e. Someone who I believe would be right said it – so it must be so? Again – no reference to the evidence/data.
These tactics are used to avoid confronting your belief system with hard evidence/data that might refute your belief system. Said refutation being an emotionally painful experience… hence the mental gymnastics to avoid it.
So if you have 18 climate models and they all fail to produce what is physically observed, at what point do you begin questioning whether the models are valid? Could they all share a fatal flaw? Like maybe carbon dioxide really doesn’t have much to do with earth’s temperature?
Crazy talk, I know.
I’m just sayin’.
These models proporting to show Mann-made global warming just don’t cut it.
Graeme Rodaughan (23:04:08) :
Good points that you make, but, in another world I inhabit we say “Don’t feed the Troll”
I like to use the price of a carbon credit as my marker. Money talks, bullshit walks. Just my 10 cents.
danappaloupe
Let me make something perfectly clear. You are in the penalty box right now (your comments are held) due to what you did yesterday and are attempting to do again today, and thats disrupt the blog to suit your purposes. Thats called trolling.
Yesterday you came into the Tips & Notes page trying to turn a section that is exactly what it says, “Tips and Notes” into your argument forum with the completely wrong assertion that Arctic Sea ice is less in 2009 than in 2008. Which is wrong and you aren’t seemingly sharp enough to realize this.
Any source you pick, NSIDC or JAXA shows the same result: More ice in 2009 than 2008, more ice in 2008 than 2007. If you are able, interpret these two graphs
http://www.ijis.iarc.uaf.edu/en/home/seaice_extent.htm
http://nsidc.org/images/arcticseaicenews/20090917_Figure2.png
If you want to discuss sea ice, pick a thread about sea ice and discuss it there where commenters will tell you exactly what I have told you. But I won’t have this thread turn into an argument over your erroneous belief that sea ice was less in 2009 than 2008 when even your favorite agency says otherwise.
Now you are trying the same discussion diversion tactics again on several threads tonight, for example trying to turn the discussion about Dr. Spencer’s findings into a religious argument. I won’t have it and I’m no the least bit concerned if you are offended. Thats the blog policy.
If you want to discuss models, that’s fine and OK by me. Otherwise cease, since we don’t allow religious discussions on WUWT. Read the policy page, the link under the masthead.
– A
NOTE TO READERS: This person has demonstrated all the classic symptoms of trolling, best to just ignore him. – A
On top of that he’s shallow. But you left his comment up. It can’t be said you delete comments like his and don’t give them a chance.
I like it that comments like his can be seen with its bias in plain view.
REPLY: He’s welcome to post on topic and on-threads with that topic. But religious discussions aren’t going to happen – A
I am proposing a genuine viewpoint which is different from the majority of the people on this blog, I ask questions, seeking a discussion about the facts. I counter number with numbers and pose serious questions about how data is being interpreted. The number of personal attacks against me far exceeeds anything I have dealt out. The worst I have said was ‘your readers need to be educated about the difference between weather and climate’, which does bring into question to intellect of the readership, but is above all a statement of facts. Your readers use 1 year of weather data to draw conclusions bout trends in climate.
The publisher of this blog is not interested in sparking good debate. There is no debate on this blog as a consequence and it is has become a place of talking points and partisan politics, yet is touted as a science blog (and a best one at that!). You call me a troll in an attempt to discredit my opinion and the questions I pose. Look up how a troll is defined, it is not me.
REPLY: Tell you what, I’ll give your your own thread. Then you can demonstrate your viewpoint to everyone. Only rule is that you have to stay on that thread. Accept or decline – A
But, Dr. Roy missed a golden opportunity to note the current lack of sunspots.
I did some thinking about the discussion about the area of sea ice. Although you never clarified which numbers you are using to make you claim of a 28.7% increase in area, you still say I am wrong.
It doesn’t matter anyway. The real important characteristic of ice as it applies to climate change is the volume of ice, expressed in thickness.
http://nsidc.org/arcticseaicenews/faq.html#really_declining
I am sorry I brought up religion in your Science Blog, it does not belong anywhere near the discussion of science if we are all indeed seeking truth.
So, Earth has warmed since the LIA. Big surprise! Wake me when the world temp reaches that of the MWP, when oarsmen of Iceland could simply row across to Greenland and establish farms.
Please not us play games; if there is new info to discredit the AGWarmists, let’s hear about that. This kind if crap serves no useful purpose, smacks of ego-driven hubris and serves nothing in establishing the truth.
Seems to me that establishing the reality of the MWP would do more to put the current panic to rest, than everything else we could do.
Back at UCLA, I took a class in Scandiavian Literature. Among the sagas assigned were “Leif the Lucky” who reached North America around 1000 CE.
He reported hostile indiians “Skralings;” They were suifficeinty armed to make the Norse to think twice.
So, the Norse went north, where the hostiles didn’t live. Right up to the northern tip of Baffin Island, and estbabished a colony there, lost later due to climate change.
But the jerkizoids insist that this never happened. God, help us,
Roy Spencer, first, thankyou so much for your work in general.
Question: I see from your and Lindzens findings that the have negative responce to (CO2-) heat.
In many debates I argument like the following (and nobody ever had any contra argument ive seen..):
“The major process of positive feedback is the reaction of water to heat:
CO2-heat => more water in atmosphere => Even more heat”
– which is of course not likely in the light of yours and Lindzens findings.
BUT. As most here knows, the basic fact is, that from 1940-today, the has not been measured more water in the atmosphere. Without more water in the armosphere, its actually “game over” for the idea of positive feedback, is it not??
I mean, its very useful to examine things as you do, but the idea of positive feedbacks has lost already before examining the effect of more water in the atmosphere?
(And then we remember that alsp CH4 has stopped rising years ago)
Water content in the atmoshere: in ther lowes levels we have very near the 1940-50 level, rest of the atmosphere far less water than in 1940. This should be game over for “positive feedbacks??
http://www.klimadebat.dk/forum/dokumentation-for-global-opvarmning-uden-for-byomraader-d12-e473-s60.php#post_6080
Anthony, the “danappaloupe” guy.. i was thinking, how about letting him make his own thread “What danappaloupe means about climate a-z” giving him free space. I think this would be joy-full for the rest of us to comment 🙂
But i understand if you think its waste of time, though.
K.R Frank Lansner
REPLY: I had done so earlier, see previous comments…he apparently hasn’t seen it yet. -A
I am not a fan of pointing out the “500 pound gorilla in the room” …
But we have one.
Not a single person has stepped up and addressed the issue that many people on this website believe, wrongly, that one year of weather data can be used to draw conclusions about climate, global warming, models etc. Even if we were talking about a climate model that we know is wrong, and designed it to be wrong, we can’t judge that model based on one year of data.
That is the only thing I care about.
REPLY: Well when you botch sea ice extent so badly… I’ve offered you your own thread where you can disucss this as you please – Accept or Reject? Second request, I won’t ask again. – A