I’ve Looked at Clouds from Both Sides Now -and Before
by Roy W. Spencer, Ph. D.
…sometimes, the most powerful evidence is right in front of your face…..
I never dreamed that anyone would dispute the claim that cloud changes can cause “cloud radiative forcing” of the climate system, in addition to their role as responding to surface temperature changes (“cloud radiative feedback”). (NOTE: “Cloud radiative forcing” traditionally has multiple meanings. Caveat emptor.)
But that’s exactly what has happened. Andy Dessler’s 2010 and 2011 papers have claimed, both implicitly and explicitly, that in the context of climate, with very few exceptions, cloud changes must be the result of temperature change only.
Shortly after we became aware of Andy’s latest paper, which finally appeared in GRL on October 1, I realized the most obvious and most powerful evidence of the existence of cloud radiative forcing was staring us in the face. We had actually alluded to this in our previous papers, but there are so many ways to approach the issue that it’s easy to get sidetracked by details, and forget about the Big Picture.
Well, the following graph is the Big Picture. It shows the 3-month variations in CERES-measured global radiative energy balance (which Dessler agrees is made up of forcing and feedback), and it also shows an estimate of the radiative feedback alone using HadCRUT3 global temperature anomalies, assuming a feedback parameter (λ) of 2 Watts per sq. meter per deg (click for full-size version):
What this graph shows is very simple, but also very powerful: The radiative variations CERES measures look nothing like what the radiative feedback should look like. You can put in any feedback parameter you want (the IPCC models range from 0.91 to 1.87…I think it could be more like 3 to 6 in the real climate system), and you will come to the same conclusion.
And if CERES is measuring something very different from radiative feedback, it must — by definition — be radiative forcing (for the detail-oriented folks, forcing = Net + feedback…where Net is very close to the negative of [LW+SW]).
The above chart makes it clear that radiative feedback is only a small portion of what CERES measures. There is no way around this conclusion.
Now, our 3 previous papers on this subject have dealt with trying to understand the extent to which this large radiative forcing signal (or whatever you want to call it) corrupts the diagnosis of feedback. That such radiative forcing exists seemed to me to be beyond dispute. Apparently, it wasn’t. Dessler (2011) tries to make the case that the radiative variations measured by CERES are not enough energy to change the temperature of the ocean mixed layer…but that is a separate issue; the issue addressed by our previous 3 papers is the extent to which radiative forcing masks radiative feedback. [For those interested, over the same period of record (April 2000 through June 2010) the standard deviation of the Levitus-observed 3-month changes in temperature with time of the upper 200 meters of the global oceans corresponds to 2.5 Watts per sq. meter]
I just wanted to put this evidence out there for people to see and understand in advance. It will be indeed part of our response to Dessler 2011, but Danny Braswell and I have so many things to say about that paper, it’s going to take time to address all of the ways in which (we think) Dessler is wrong, misused our model, and misrepresented our position.
I have to apologize to Professor Dessler for messing up his name in my comment at 6:09 AM. The extra “r” is maybe caused by to much feedback from delta-R-coffee.
For my own understanding (and it might help others), I consider “forcings” to be inputs to a system. “Feedbacks” to be parts of the system’s output that are fed back into the system by mixing them with the inputs.
Negative feedbacks promote the stability while positive ones increase the responsiveness of the system.
In electronics, one tends to design using negative feedbacks.
Being the result of natural selection, our planet, I think, would contain mainly negative feedbacks.
“John Marshall says:
October 9, 2011 at 1:53 am
i wait with baited breath. But when a scientist tells me that heat will travel, by whatever method, from cold to hot as Dr. Spencer told me in an email, I view all his work with suspicion.”
Don’t you mean he said photons can travel from a cooler body to a warmer body?
RE: Nick Stokes
October 9, 2011 at 7:26 am
Nick, You should give a class in the repression of reasoning.
Can you really not figure this out on your own?
From Dessler 2011…
6. Conclusions
These calculations show that clouds did not cause
significant climate change over the last decade (over the
decades or centuries relevant for long‐term climate change,
clouds acting as a feedback can indeed cause significant
warming). Rather, the evolution of the surface and atmo-
sphere during ENSO variations are dominated by oceanic
heat transport.
The forcing/feedback issue is a huge problem, as it depends upon the boundaries of the system, which can be defined in a number of ways. Response is less confusing for me, Rs to a +/-Fs. Too much is assumed and not stated.
Bottom up versus top down modeling is confusing as well. Like the change in emissivity with pressure in the atmosphere issue, obvious how it is considered in some cases. As long as the nets match, okay, a little showmanship, but nets should be clearly defined.
“The Australian Labor Party….. The political party that taxed the air we breathe.”
When the natural inclination of people on the left, no matter where they live, is to raise taxes, and reduce liberty, what should rational people conclude about what the left really wants?
And after CO2 fades as a reason to raise taxes and reduces liberty, some future swing of the climate to being much colder will trigger what reaction from the left? To raise taxes and reduce liberty in order to restore balance to the climate!
We used to have sufficient levels of both prosperity and liberty to allow us to give in to leftists on their demands. But those days are over. We could never really afford their Utopia. It was never really “sustainable”, a concept the left loves to scold the rest of us about.
Ask why is it so? says:
October 9, 2011 at 5:25 am
Did you forget about night?
davidmhoffer says:
October 9, 2011 at 12:56 am
Given that the list of matters it sounds like you intend to take Dessler to school on…I mean to rebutt him on…could it be possible to ask that you publish in installments? Say two or three a week for as long as it takes?
For us “interested but I’m not a PhD candidate” types, we can’t absorb the thing as fast as you can write it, and we need time to catch up. Besides, by stretching it out, you put Dessler in a real bind. He can’t cherry pick one or two minor items out of the whole paper and then claim he has debunked the whole thing (a favourite tactic of the Team I’ve noticed), he has to respond to each piece as it comes out…our look like he doesn’t have a response at all. Best of all though, when defending himself on Chapter 1, he has to respond with facts that very well may rob him of his defense in Chapter 4, and so on.
————————
I second that request.
Re: “2.5 Watts per sq. meter”
Isn’t that approximately the same as the influence density of the “Watts Up With That?” blog?
😉
“cloud changes must be the result of temperature change only.” This has been one of the most baffling ideas I have come across in climate science. It seems some have missed some of the simpliest observations or at least ignored them.
Global cloud cover between the early 1980’s and early 2000’s declined through a period of warming. If the temperature change only affects cloud, then during this same period global cloud levels would have increased, not decreased. Warming temperatures are suppose to increase water vapor and cloud formation, not decrease them.
Therefore this idea that ‘cloud changes must be the result of temperature change only’ are clearly wrong. The observed evidence shows using the satellite data since 1983 (cloud levels) that, declining cloud levels caused the temperature to increase with increasing surface solar radiation. Hence, that is the main reason why we can determine the chicken or the egg. (2nd paragraph) Since the decline has stopped and become stable, global temperatures have stopped rising.
In my recent essay Obfuscation http://retreadresources.com/blog/?p=873 I review what is and is not: Science is:
1. Posing a question.
2. Constructing a hypothesis, or several. (I like several, that the geoscience way)
3. Created an experiment(s) to test this hypothesis or hypotheses.
4. Specify the parameters that would validate or support one or more hypothesis.
5. Carried out the experiment(s). Note models are not definitive data producing experiments.
Science is not:
1. Determine the outcome required to secure continued and additional funding
2. Construct a model to generate the required outcome and do nothing to calibrate it to reality.
3. Locate data that supports the model and outcomes from 1 above. Ignore anything contrary to your ideological position.
4. Make sure the model can not be calibrated to reality.
5. Announce the predictive power of your model.
6. Make one or more predictions far enough into the future, that you’ll be retired by the time it will be falsified.
Something all of you know and have seen many times. Sometimes I think so called professionals need a big bit of reeducation.
I think a glossary of terms is a good idea. As a layman, I am in a good position to list terms that are understood by the lay, and put question marks aginst those that baffle me
so Here is my starter, feel free to contribute
Al – A unit of hot air, often associated with lots of front. aka a hypocratee, or a DAISNAID (do as i say not as I do)
Albedo – Reflectiveness of stuff.
Briff – A long tongue. not of ice, that can slurp into fjords or other crevices
Canard – A fib. a big fib. see Tree rings
CO2 – a trace greenhouse gas. plant food. Supposed by some to be evil because although it is a small scale player, mankind produces some, so at last we have someone to blame. Mankind will be arrested shortly.
Denier – A fool who refuses to believe that human knowledge has peaked.
Dessler – A rapid turnaround coattail rider. See Spencer.
Energy – This is what its all about.
Finance – All sceptics are paid one million dollars per day by big oil. FACT
Gore – Inventor of the internet, the pioneer who was first to discover that the centre of the earth was millions of degrees, and the first to realise that science had stopped. We already knew everything. Schtum. stop arguing. stop questioning. schtum.
HadCrut – ?
IPCC – A body that was set up to advance the science by using anti-science methods. Unable to understand that concensus to science is like captivity to a wild animal. The AR are a torch to be lit, not a bucket to be filled.
Jones – An English unit of BS (See blivett, the US equiv. i.e. putting 2 cwt of BS in a 1 cwt bag)
Kenji – A member of the Union of concerned scientists. Neither concerned, a scientist or a real member. but has a credit card
Lysenkoism – ?
Mann – A personality disorder. Drives the subject to believe they are special, living in special times, and only they have the answer. Harmless untill a few gather together at the same place at the same time, then they can gather a momentum and produce ‘self fullfilling prophesies’.
They will never apologise for the horrors they inflict – see the Salem witch trials
Non Disclosure – A late 20C, early 21C concept designed to improve the scientific process. How this works is even more obscure than how the conjunction of mars with venus affects your love prospects.
Organisations ?
Predictions – See falsifiability
Quotes – The whole aim of practical politics is to keep the populace alarmed
Risk Assessment ?
Spencer – Keep it up mate. Keep it up.
Travesty Trenbo – To do a ‘Travesty Trenbo’ is to paint yourself into a corner , for no apparent reason. i.e. you tell your children that the tooth fairy left the money for the tooth at midnight. But the child says ‘I was awake at midnight and I was with a friend’. To do a TT you would say ‘ah yes, but the tooth fairy works on PST’ Then when the kid says ‘it wasnt my tooth, it was my friends tooth’ To do a TT, you would say ‘ah yes, but the tooth fairy knows that some teeth are deep teeth, that wont surface for a million years’ i.e. to make increasingly unbelievably outrageous statements, instead of admitting to a wise kid that there is, in fact, no tooth fairy
UEA – a polytechnic in England, that wants to be a university
Viner – To do a viner. This is to make a claim so far in the future that you never have to worry about being caught out. Except that when you are a young acolyte, 10 years seems like a long time. It isnt. Snow will become a thing of the past ? yes . and my butt is a cream bun.
REPLY: We have a glossary in the menu below the header – Anthony
The dogma cannot allow for the possibility that clouds can be a source of climate forcing. Why?
Because such forcing would allow for the possibility of a cosmic ray effect or simply unforced chaotic changes that would upset the findings of climate models. And that would imply a much small climate sensitivity, and with that would go the case for the billions in funding and expanded government control of industry.
Got it? It can’t happen. It can’t be allowed to happen.
One other thought as to meeting the level of understanding of both the interested/layman and intelligent, and the highly knowledgable with regards to the scientific terms/details. Give it to us both ways. Toss out the details for the geek type and a summary for the layman. I’m on the border.
Thank you WUWT and Dr. Spencer. This is what we have been waiting for!
Someone needs to write a primer text on this topic entitled Clouds for Dummies.
This book could include a discussion of the cloud modeling philosophies employed by climate modelers under a sub-chapter entitled Cloud Computing.
more statistics. oh, joy.
the statistics have stared everyone in the face to death.
i know it was never about science – but wondering why people still pretend it is – and that statistics IS science.
one good experiment would be far more useful and significant than all the statistics ever shoveled. but who wants to actually make sense and lose fame & funding?
REPLY: We have a glossary in the menu below the header – Anthony
I know that. just my little joke
“i wait with baited breath. But when a scientist tells me that heat will travel, by whatever method, from cold to hot as Dr. Spencer told me in an email, I view all his work with suspicion.”
And with what do you bait your breath? If you were waiting with bated breath, now, you might make more sense.
I look forward to more on the cloud forcing debate, but not being a climate scientist, but instead an interested layman, I wouldn’t mind someone translating the more obscure language into plain English.
Taken directly from Dessler’s paper:
“And since most of the climate variations over this
period were due to ENSO, this suggests that the ability to
reproduce ENSO is what’s being tested here, not anything
directly related to equilibrium climate sensitivity.”
—–
Question: Do you or do you not agree with this? Why or why not?
Over the short time period observed, it seems Dessler is quite correct: ENSO changes (specifically heat transport by the ocean) drives changes in surface temperatures which drive cloud formation. In short, during the short time frame involved, clouds are reacting to heat transport by the oceans, with whatever affects of clouds on actual surface temperatures to be very small when compared to the effects of ocean heat transport on surface temperatures.
Eternal Optimist
Second derivative definition for
Viner
Someone who has a cushy job with the British Council promoting “Climate Change”, gets to travel round the world and earns £70K pa
Eternal Optimist says:
October 9, 2011 at 10:12 am
I think a glossary of terms is a good idea. As a layman, I am in a good position to list terms that are understood by the lay, and put question marks aginst those that baffle me
so Here is my starter, feel free to contribute….
Lysenkoism – ?
_____________________________________
Professor to grad student: “Shut up and keep cutting out all the rats tails, ERRRRrrrr data points that do not fit my curve.”</i.
The only CAGW conjecture for clouds and therefore positive feedback was to support increasing global temperatures with increasing cloud levels. This has simply not occured and been falsified a while now, plus with increasing evidence of negative feedback, not positive. Thats why an actual AGW theory using clouds could have been falsible, but never promoted because the Earth has never supported such assumption. This is ignored and dismissed for the simple reason the CAGW conjecture only exists with it and the only way to get away from reality is use a model instead.
Clouds are a source of climate forcing and the observed evidence from the planet shows this. (discussed in my previous post)
Clouds modulate the the solar energy that warms the earth. This can make a huge difference to local temperatures and heat content on both short and longer term timescales. If you don’t believe me, book a UK beach holiday for next summer.
“John Marshall says:
October 9, 2011 at 1:53 am
But when a scientist tells me that heat will travel, by whatever method, from cold to hot as Dr. Spencer told me in an email, I view all his work with suspicion.
The you should hold all of mainstream climate science in suspicion starting with K&T and the IPCC. Their claim is that the sun, with a black body temperature of 6C (342 w.m2 at TOA), and GHG with a block-body temperature of 0C (321 w/m2) , combine together to heat the surface of the earth to a block-body temperature of 15C (392 w/m2).”
That is the model for climate science. Another shell that is the sun, and inner shell that is GHG, and the core that is the surface. The solar shell is 6C, the GHG shell is 0C and the core is 15C.
Because the GHG is transparent in one direction, it is argued that the GHG shell will reflect the radiation back from the core, allowing the core to be warmer than either of the shells that surround it.
Coincidentally this is the basis for many perpetual motion machines in science fiction. The ability to take the heat from two cold objects and add it together using a one way mirror to create one hot item.
I shall never forget an August afternoon in northern Arkansas around 15 years ago. It started as a bright sunny day, but the high was forecast at 62 degrees F, a figure which obviously sounded ridiculous. By 10 o’ clock, the clouds were building fast and then at midday the heavens opened for about eight hours, with occasional heavy hail.
I never thought it would be possible to feel cold in the southern US in the afternoon in mid-summer.
I assume this was a case of severe negative feedback. The process of daytime cloud formation and subsequent precipitation must be a huge negative feedback in much of the tropics, something which is presumably ignored by the IPCC et alia.