Tuesday, September 06, 2011

GRL doi:10.1029/2011GL049236 Andy Dessler does not like Spencer and Braswell very much

UPDATE: Video (Thnx to Sou)



Andrew Dessler has a new, recently awaited take (open preprint) on Spencer and Braswell 2011 and Lindzen and Choi 2011. Skeptical Science goes over the cherry picking in SB. Basically, the former looked only at the models that were not very sensitive to El Nino and found them wanting in a comparison where El Nino dominated, and both made interesting choices of data. Skeptical Science goes through this in detail. You gotta get up early in the morning to beat them Aussies. UPDATE: Gavin has a measured take on the blowup @ Real Climate, more meta than not.

Eli is more interested in the setup. Dessler notices that when both LC and SB write an equation for the change in the ocean surface temperature on a short term basis, ∆Tsas a function of the heating of the climate system by the ocean, ∆Focean and the change in the TOA flux due to clouds,

C dTs/dt=∆Rcloud+∆Focean−λ∆Ts

they bundle the feedbacks into λ, but this defines the clouds and oceans as the source of ∆Ts not as the result. SB specifically separate cloud forcing from response, AKA, they assume what they wish to prove which is not such a bad tactic if you want to show that the something you assumed is wrong, e.g. induce a contradiction, but it does not work as well in the other direction. However, are the oceans part of the climate system which SB and LC are modeling? If so the ∆Focean forcing term is driving changes in the temperature of the oceans, but if the ocean is part of the climate system then the ocean respond to changes in the system, i.e. this model confuses forcings and feeedbacks. Dessler puts it this way
The formulation of Eq. 1 is potentially problematic because the climate system is defined to include the ocean, yet one of the heating terms is flow of energy to/from the ocean (∆Focean). This leads to the contradictory situation where heating of their ocean, yet one of the heating terms is flow of energy to/from climate system by the ocean (∆Focean > 0) causes an increase of energy in the ocean (C(dTs/dt) > 0), apparently violating energy conservation. While it may be possible to define the terms so that Eq. 1 conserves energy, LC11 and SB11 do not provide enough information to show that they have actually done so.
One possible out is to claim that neither the oceans nor clouds are forced on a monthly time scale (which kinda says El Nino is external to the system, all flail down) or to jigger the constants C and λ which provides the freedom to pick the ratios of ∆Rcloud and ∆Focean

The issue of the specific heat is indicative. The standard value is ~168 W-month m-2K-1 which both LC and Dessler use (also see for example Schwartz). This is for a depth of ~100 m, but SB use 3 W-month m-2K-1 for a depth of 25 m. If you simply scale this it is equivalent to 12 W-month m-2K-1, still way low. However, this shallow ocean would respond faster to any changes in the system as SB discuss as justification for choosing such a low value, making the assumption of decoupling from the system even worse.

Still, Andy is a nice guy
However, to comprehensively evaluate the arguments of LC11 and SB11, I simply note this potential problem and assume in the rest of the paper that Eq. 1 is correct.
Which is where Skeptical Science comes in.

Eli? Eli is fond of conservation of energy.

41 comments:

Sou said...

Rather than send people to WTFUWT, Andrew Dessler has posted a link to his paper (on RealClimate) - here:
http://geotest.tamu.edu/userfiles/216/Dessler2011.pdf

EliRabett said...

Done

Anonymous said...

Have the bunnies seen Roy's latest attempt to defame Dessler?

http://www.drroyspencer.com/2011/09/dessler-vs-rick-perry-is-the-2011texas-drought-evidence-of-human-caused-climate-change/

Evidently Roy has not paid any attention to what Dr. Nielsen-Gammon has been saying about the drought over most of the Southern Great Plains, for example, see here:

http://blog.chron.com/climateabyss/2011/08/texas-drought-spot-the-outlier/

Now why did Roy not show the graph shown by Dr. N-G above?

Come on bunnies, please remind Roy of this graph-- I cannot as I have been banned, evidently in part b/c Spencer thinks that I am Dr. Trenberth.

Please do not let Roy's attempt at generating a smokescreen to detract from his dire failings work.

Obscurity

Anonymous said...

Here is the URL for the SkS article on Dessler's refutation of LC11 and SB11.

http://www.skepticalscience.com/Dessler-2011-Debunks-Roy-Spencer-And-Richard-Lindzen.html

Enjoy.

Sou said...

And a video by Dessler about his paper, to send to your non-sciency friends.

Never seen anyone do that before - what a great move.

Anonymous said...

Dr. Jay Cadbury, phd.

Well ho ho ho. For all the fanboys here, the model that Eli is ripping was suggested to Dr. Spencer by Isacc Held. Dr. Held endorses global warming and believes it's human induced. What more do you want Dr. Spencer to do? He asked a colleague who has an opposing viewpoint which model to use and he did. For shame, Eli.

Horatio Algeranon said...

Horatio is fond of the "Conservation of Goofiness"

The Conservation of Goofiness
Is a law that governs Nature
Goofiness can't be created or destroyed,
(Without the legislature)
It only changes form
As it flows about the earth
The Goofiness of the Universe
Is constant (for what it's worth)




Editors note: If recent events in the climate science world make it seem as if the total "goofiness" of the universe is actually undergoing a sharp increase, it's only because most folks actually try to hide their goofiness, not flaunt it like some sort of medal of honor.

Anonymous said...

Dr. Jay Cadbury, phd.

Furthermore, Eli is basically saying that it is fact that clouds don't cause climate change, which is a regurgitation of Kevin Trenberth. All I'm going to say is you're not very smart if you believe that. It's quite ironic that the 2 most respected global warming scientists believe this is a good study, while the bums at realclimate cry.

Doug said...

Dr. Jay Cadbury, phd. [sic]:

... clouds don't cause climate change, which is a regurgitation of Kevin Trenberth.

Trenberth's book "Climate System Modeling" goes into the role of clouds in shaping our climate quite extensively, probably is the best place to discover what he actually is prepared to say about the topic.

Dr. Dr., why not squeeze your opinion into the mold of reality by getting synchronized with Trenberth?

Anonymous said...

Ray,

You have been duped by Spencer. Yes, held might have suggested the model in question. But what Roy is not telling you is how badly he forced it (the parameters he used to "tune" it are unphysical) to arrive at a predetermined answer/belief.

Dr. Held will not be impressed that Roy is trying to use this lame and transparent argument-- held is a much. much better scientists than that.

Unfortunate, that uncritical fans of Roy are buying yet more half-truths from Spencer.


And as for your claim that "clouds don't cause climate change" that would be a lie by Spencer and a complete misrepresentation of Dessler's and Trenberths's positions. It also shows that you have not read Dessler's papers and have not watched his video.

Please do so before making a fool of yourself.

Obscurity

Holly Stick said...

On the other hand Horatio and his Editors appear to think that cloud cover may hide goofiness but does not decrease net goofiness.

I am not convinced that Horatio's thesis is correct. If human goofs are able to find each other on the internet and get together at goofiness conventions where they may well breed like rabbits (pray excuse the expression) will their supergoofy offspring not emit more intense goofiness, thus leading an overall removal of gravity?

J Bowers said...

Someone's repeating The Motl.

Belette said...

Whether or not equation 1 is valid is important, I think. If it is invalid, then you need go no further: the entire thing is junk (the converse isn't true, of course: eq 1 being valid doesn't make the paper good).

D re-names it to "C dTs/dt=∆Rcloud+∆Focean−λ∆Ts" but that isn't the naming that S+B give it. The crux bit is then ∆Focean, which S+B call S (incidentally, S+B calling non-radiative forcing S and radiative forcing N is very confusing; you'd expect them the other way round).

D says "This leads to the contradictory situation where heating of their ocean, yet one of the heating terms is flow of energy to/from climate system by the ocean (∆Focean > 0) causes an increase of energy in the ocean (C(dTs/dt) > 0), apparently violating energy conservation" but I can't see how you work out what sign convention S+B are using. Indeed S doesn't seem to be very clearly defined at all, except by the rather vague "non-radiative forcing" and a couple of examples of what might belong in S.

I tried to work out their sign convention by reading further down, but it didn't seem to come back into the analysis, which is also odd. On page 1607 equation 2 has an S in it, but since that S is radiative I think it must be a different S. On p 1610 S re-appears, but in the odd guise of a series of not very clearly specified random numbers.

All in all D's "they do not provide enough information" seems quite mild.

David B. Benson said...

Eli should read Emmy Neother's (first) theorem.

Anonymous said...

Just in case anyone happens to still care what Steve believes (CA-- who are they again?):

http://climateaudit.org/2011/09/06/the-stone-in-trenberths-shoe/

Who needs the "young and the restless" when we have such drama queens like Steve and Woy to entertain us.

Funny, word verification sounds a lot like "scheize", pretty apt give my posts discusses CA and Spencer :)

Rattus Norvegicus said...

If you think CA or WUWT is sad, Judith is letting her brains leak out. She missed the rather blatant cherry pick pointed out by Dessler!

David B. Benson said...

Rattus Norvegicus --- Any left to leak?

Rattus Norvegicus said...

Eh, the flow has been slowing down, but this may mark the end.

David B. Benson said...

Oops. Emmy Noether.

andrew adams said...

Rattus,

The most amusing thing on that thread at Curry's is Steven Mosher continually popping up to claim it's all Michael Mann's fault.

dhogaza said...

RN:

"She missed the rather blatant cherry pick pointed out by Dessler!"

Well, she did say 'if they did that, that's a no-no" but even after I provided the obvious hint, she didn't bother to check either the paper or Dessler's response which points it out. Thanks for also pointing out the blatantly obvious.

And, yes, AA, Mosher's pretty funny ... the strongest argument they've got seems to be the 4 year-old child's rant ... "Mike did it first!!!!!".

Dallas said...

Spencer has responded to the cherry picking, how good is he at picking ripe fruit?

Anonymous said...

Dr. Jay Cadbury, phd.

@Ratty Norwegian

Roy's cherry pick huh? Excuse me Ratty, your side has caused global cherry prices to soar, as you have a near monopoly on cherries. You guys started the warming trend and started at 1800 or 1850, I've seen both starting points used. Meanwhile, you tactically avoided telling the public the earth is below it's average temperature and below its average co2 level. Making extremely hypocritical statements hurts your credibility, Ratty.

Doug said...

As predicted, dead cat bounce.

Would Dessler's paper have been noticed at the "Ars Technica" level of the food chain without Wagner's resignation? I'll be bold and give it a solid "no."

dhogaza said...

RN:

"Thanks for also pointing out the blatantly obvious."

In case it wasn't clear, I meant thanks for pointing it out to Judith.

Anonymous said...

OK I'll ask: What is the reference or link to Issac Held?

Pete Dunkelberg

Anonymous said...

Pete,

Can you elaborate please?

Anonymous said...

I asked first! In this thread and at least one other I find Held said this! No he didn't. Did so.

Pete

Anonymous said...

Pete,

Despite his name being thrown around, Held is not very interested in this debate/tiff, or at least he wasn't until very recently.

Roy claims that Held suggested he use the one-box model. Roy also claims that Held has said that SB11 was a good paper. I have not been able to find such a claim, at least not on the web.

So perhaps it might be that Held will shed some light on this relatively soon.

Anonymous said...

@Dr Chocolate:

"the earth is below it's average temperature and below its average co2 level"

What's this, comedy hour at the undergraduate debating society?

William T

J Bowers said...

@ Doug, would it have been in Ars Tecnhica if FOX, Forbes and Heartland hadn't made such a broo-ha about SB11?

Doug said...

The collective hippocampus of our popular media is so damaged or congenitally absent that the industry resembles a case study from one of Oliver Sacks' books. There's no consolidation of memory to allow retrieval of events and thus narrative continuity from last week or last month, let alone last year.

For my part I'm quite certain the connection between Dessler's paper and Spencer's PR blitz would never have been made without a sensational jolt.

Paul said...

Pete,

Isaac Held's blog is well worth following. Check out his third and fourth posts. They describe one and a two dimensional models and how these simple models can help us understand more complex ones. They might be similar to Spenser's but are much more clearly explained. Held makes no grand claims for their utility beyond their instructional utility.

http://www.gfdl.noaa.gov/blog/isaac-held/

Paul Middents

Anonymous said...

Clouds don't cause clouds.

Jeffrey "Runaway Warning" Davis

Horatio Algeranon said...

"Both Sides Now"

Horatio Algeranon's rendition of the Joni Mitchell song

Rows and flows of Pachauri hair
And IPCC castles in the air
And alarmist scientists ev'rywhere
I've looked at clouds that way
But now they only block the sun
They change the temperature for everyone
So many papers I would have done
But clouds got in my way
I've looked at clouds from both sides now
As feedback and forcing, and still somehow
It's cloud illusions I recall
I really don't know clouds at all

JCH said...

Pete - I believe they are saying the model was recommended to SB by Issac Held, who did not Held their hands when they f'd it up.

David B. Benson said...

Rain makes applesauce.

Horatio Algeranon said...

More "Both Sides Now" (per)versification:
(see above)

...

Mann's and Jones' and hockey sticks
The human driven temp uptick
And arctic sea ice melting quick
I've looked at graphs that way

But now it's just another show
You leave 'em laughing when you go
And if you care, don't let them know
Don't give yourself away

I've looked at graphs from both sides now
From Mann and Watts and still somehow
It's graphicillusions I recall
I really don't know graphs at all

Web awards and feeling proud
To say "Conspiracy" right out loud
Dreams and schemes and circus crowds
I've looked at climate that way

But now old colleagues are acting strange
They shake their heads, they say I've changed
Well something's lost, but something's gained
In blogging every day

I've looked at climate from both sides now
From journals and blogs and still somehow
It's skepticillusions I recall
I really don't know climate at all

I've looked at climate from both sides now
From up and down, and still somehow
It's skepticillusions I recall
I really don't know climate at all

Anonymous said...

For the 14 people who might not have heard:

http://neven1.typepad.com/blog/2011/09/historical-minimum-in-sea-ice-extent.html

Jeffrey "No ice and just a few drops of branch water" Davis

EliRabett said...

Neven finally went over to Uni Bremen rather than the JAXA analysis. (Yes Eli knows)

Jay Alt said...

The paper (SB11) caused me to wonder about the suitability of one-dimensional models to estimate sensitivity. I found they are one method used to do it, among many. I see now I. Held confirming that. Of course, the work would need to be done properly. from:

An Introduction to Simple Climate Models used in the IPCC SAR ed. John Houghton 1997 (~48 pgs.)
http://www.ipcc.ch/pdf/technical-papers/paper-II-en.pdf

(~ pg 14). . . Radiative-convective models thus provide one means for determining one of the key feedbacks which are important to climate sensitivity through a combination of observations and well established physical processes.

One-dimensional upwelling-diffusion ocean models.. . .
This model is used primarily to study the role of the oceans in the surface temperature response to changes in radiative forcing.

see associated fig 2 of such a model.