Blogs Section
Thoughts on everything from climate modeling to energy policy.

Global Warming Debunked! Or…not.

Repost This

The headline on, highlighted on the Drudgereport, is just too juicy: "New NASA Data," it says, "Blow Gaping Hole in Global Warming Alarmism."

As many of the scientists I know say in response to an eyebrow-raising claim, "Important... if true."

It's the "if" part that's problematic here. First, the Forbes headline is way more sensational than anything Dr. Roy Spencer actually says in his new paper. As Climate Central chief scientist Phil Duffy says:

The paper itself is far less aggressive in its claims than the Forbes article is. The paper's abstract, for example concludes: 

“It is concluded that atmospheric feedback diagnosis of the climate system remains an unsolved problem, due primarily to the inability to distinguish between radiative forcing and radiative feedback in satellite radiative budget observations”

 This is hardly a sweeping claim! 

But his underlying theory (both here and in earlier papers; this isn't a new idea on his part) are almost universally doubted by other climate scientists. Spencer, himself a bona fide climate scientist, albeit one whose views often lie outside the consensus, basically says that changes in cloud cover are a major cause of climate change.

Just about everyone else in the field, by contrast, considers clouds to be a feedback mechanism in the climate system. That means that warming alters the rate and type of clouds that form, and those in turn affect temperature — most scientists think they drive it up further, although some think not by much, and they could actually exert a small net cooling. The warming comes first; the clouds respond.

Things like changes in the Sun's brightness, by contrast are a forcing mechanism — they push on the climate system from outside, and make it warm up or cool down. (Greenhouse gases like carbon dioxide, or CO2, can be both. Add more to the atmosphere by burning fossil fuels, and the planet warms. But if the planet warms for any reason, more CO2 enters the atmosphere from natural sources. So CO2, unlike clouds, is both a forcing and a feedback.) All of this is Climate Science 101 (maybe the spring semester).

Now Spencer is saying that data from NASA's Terra satellite supports his controversial claim. This already shows the Forbes headline to be somewhat misleading: it's not that NASA data are blowing a hole in anything. It's that Spencer's interpretation of NASA data are blowing... something, somewhere.

But that interpretation depends on a climate model created by Spencer, and a number of climate scientists, having read the paper, are not impressed. Andrew Dessler, for example, from Texas A&M University, says in an email to me that 

Overall, the argument made in all of these papers... is extremely weak. What they do is show some data, then they show a very simple model with some free parameters that they tweak until they fit the data. They then conclude that their model is right. However, if the underlying model is wrong, then the agreement between the model and data proves nothing.

The underlying model, Dessler thinks, is not just wrong — it's badly, badly wrong (I wrote about some of Dessler's work in TIME last year on behalf of Climate Central). 

If Spencer were right, then clouds would be a major cause of El Niño cycles — which we know is not correct. Talk to any expert [on those cycles] and tell them that clouds cause [them] and they'll laugh at you. 

You can see more in an email exchange between Dessler and Spencer that took place a number of months ago.

Kevin Trenberth of the National Center for Atmospheric Research, was a little more blunt. He emailed me to say, in part:

I find the whole discussion [in Spencer's new paper] to be out of touch with reality... Nearly all of the variations in water vapor and clouds, except for those affected by aerosol[s], are a response to the weather and climate variations; they are NOT a forcing. This is a major error that continues in Spencer's work...

Even if you define the extremely carefully thought out projections in global temperatures and other climate factors put together by hundreds of responsible scientists (now being updated to include new research) as "alarmist," which is more than a little absurd, and even if the new paper by Spencer and his collaborator William Braswell bolsters their argument slightly — which is debatable — it would still take an awful lot more than this to blow a hole in anything, no matter what some headlines say.


By Bob Berwyn (Frisco Colorado)
on July 28th, 2011

Blowing a hole ... ? More like blowing smoke.

Reply to this comment

By Don Monroe (Murray Hill, NJ 07901)
on July 28th, 2011

Trenberth’s comment might be a little hard to appreciate without knowing the important distinction climate scientists draw between a “feedback” that follows changes and a “forcing” that drives them. Real Climate <a href=“”>discussed thisdifference<a> in the context of water vapor back in 2005 (and probably more recently, as well):

While water vapour is indeed the most important greenhouse gas, the issue that makes it a feedback (rather than a forcing) is the relatively short residence time for water in the atmosphere (around 10 days).


Reply to this comment

By anonymouse (cheese)
on July 29th, 2011

The head scientist on this study is an intelligent design flunky.  That about says it all.

Reply to this comment

By Chief Hydrologist (Taranganba)
on July 30th, 2011

”˜The canonical way to think about clouds is that they are a feedback””as the climate warms, clouds will change in response and either amplify, (positive cloud feedback) or ameliorate (negative cloud feedback) the initial change.

What this new paper is arguing is that clouds are forcing the climate, rather than the more traditional way of thinking of them as a feedback.’  Dessler today

”˜Much work has been done on ENSO over the past few decades and pretty much everyone agrees that it’s a stochastically triggered, coupled dynamic mode of the atmosphere, ocean system.  I’ve never seen any suggestion that it’s triggered by clouds. To the extent that clouds amplify ENSO, that’s the cloud feedback, and that is what I measure in my paper.’ Dessler yesterday

”˜Finally, since much of the temperature variability during 2000”“2010 was due to ENSO (Dessler 2010) we conclude that ENSO-related temperature variations are partly radiatively forced. We hypothesize that changes in the coupled ocean-atmosphere circulation during the El Niño and La Niña phases of ENSO cause differing changes in cloud cover, which then modulate the radiative balance of the climate system.’ Spencer and Braswell 2011

”˜It is not controversial to state that climate models are deficient in terms of tropical variability in the atmosphere on many timescales [Lin et al., 2006; Lin, 2007] and a more realistic simulation of ENSO events in coupled simulations remains a high priority for model developers. During El Niño, the warming of the tropical eastern Pacific and associated changes in the Walker circulation, atmospheric stability, and winds lead to decreases in stratocumulus clouds, increased solar radiation at the surface, and an enhanced warming.’ Trenberth et al 2009

S&B say that there CERES radiative flux varies from that in models. Not in question.  That ‘sensitivity’ with feedbacks can’t be calculated this way because there ENSO radiative and non-radiative feedbacks.  Not surprising. 

Veracity in communicating science is a victim of the climate wars. 

Reply to this comment

By Doug Cotton (Sydney, NSW Australia)
on July 31st, 2011

If clouds cannot be a forcing agent then why is it generally cooler on a cloudy day?  Surely more incoming solar insolation is reflected straight back to space the greater the cloud cover.  If you accept that cosmic rays are involved in cloud formation, then it’s a small step to accept that increases in solar winds are correlated with reductions in cloud formation as these winds “blow away” cosmic rays.  And if you accept that there are cycles in sunspot activity, and that NASA’s predictions of lower levels than 1907 are valid and that absence of sunspot activity correlated well with the Little Ice Age then maybe you won’t get so alarmed about supposed potential global warming.  I’m not: because there has been absolutely no accumulation of heat in the oceans (as per the temperatures measured by NASA at sea surface) since 2003 - as proven here:

Now, even if there were any accumulation of heat in the sub-zero upper atmosphere it cannot return to earth by convection (as in a greenhouse) because the Second Law of Thermodynamics does not apply in the atmosphere due to differing pressure.  The temperature gradient from the core produces temperatures of about 300 deg.C at 10,000 metres coming down to about 10 deg.C at the surface, at least in Germany: and so even if radiated heat penetrates the crust a bit it won’t get very far and won’t build up in the long run due to the net outward flow of heat coming down that temperature slope.  If there is a heat build up of any significance, the only place that will affect our living zone is the oceans.  But they have not accumulated heat since 2003 and the data are not random noise because of the consistency of the INTRA-annual cycles

If you want to know why all heat from solar insolation is short lived (rarely more than 24 hours) read the first few paragraphs at my site Variations in long-term climate can only come from (a)  variations in intensity of solar insolation (b) variations in cloud cover - reflecting back to space (c) variations in the heat flow from the core and crust - such heat being generated by decay of radioactive isotopes, nuclear fission, friction caused in the core by tides and currents resulting from, primarily, the moon’s gravity but to some extent, Jupiter and Saturn’s (d)  effects of magnetic forces on charged ions (e) your suggestions?  That heat has to get out and it has been doing so over the life of the Earth, supplying at least 95% of the warming of the crust from 0 deg.K to a mean of something around 280 to 285 deg.K.  The sun adds a temporary 12 to 15 degrees on average, give or take a bit.  Carbon dioxide levels don’t come into it for the detailed reasons explained on my site.


Reply to this comment

By Joe Hunkins (Talent, Oregon 97540)
on August 1st, 2011

Forbes hyperbole about this study aside, one needs no study to “blow a hole” in the alarmist position, which is now very naively accepted (apparently even here?) with essentially no data or research to support a case for looming climate catastrophe.

The earth is warming, the warming is probably caused mostly by human activity, but the consequences remain unclear even after decades of close observation of climate and the environment.  This paper and an increasing number of mathematically robust studies are starting to suggest that climate modelling remains very problematic.  Nothing new there for the informed, but ironically this really could be big news ... for those who insist on remaining alarmists at heart.

Reply to this comment

By Alex the Seal (Melbourne 3000)
on August 1st, 2011

@ Joe: You classify this as a “Mathematically robust study”. but “computer modelling remains problematic”.

Spencer’s paper IS based on a computer model. Isn’t it interesting that the same people who have no confidence in computer modelling are now cheering this on like it’s Jesus second coming. Why? Because it supports your predetermined point of view. This is the definition of unscientific thinking.

Reply to this comment

By Daniel J. Andrews
on August 3rd, 2011

@Alex. Exactly. That was my thought too. For decades we’ve heard that computer models can’t be trusted, we don’t know enough, they’re all wrong, etc, but soon as a model comes along that they think supports their belief, they hoist it to the shoulders and parade through the streets with it.

Reply to this comment

By Richard Sumpter (Lenexa, KS)
on August 4th, 2011

To Doug Cotton:
Much of your argument rests on your own “if/then” statement regarding the role of cosmic rays in cloud formation.  There is no empirical evidence to establish this link.  I would refer you to:

Reply to this comment

on August 7th, 2011

Alex perhaps I didn’t make my point clearly enough, which was simply that the current levels of alarm about climate catastrophe are not justified based on the current state of mainstream climate science.  Surely you don’t challenge that assertion.  With respect to Spencer it’s not so much about being skeptical of modelling, it’s about the inherent uncertainties being greater than generally advertised.  It’s an arguably point that’ll need to shake out as more studies address it adequately.  For reasons I don’t understand folks like you seem to think model accuracy is not a debatable point.  This is a rather preposterous assertion until models start predicting the future more accurately.

Reply to this comment

By Susan Anderson (Boston MA)
on August 13th, 2011

It’s really amazing that some people feel they need only assert their opinions with sufficient force to be believed.  Arguments against articles here and elsewhere need to be supported with facts.

Explaining away the world’s climate developments is going to become increasingly harder as time goes on.

I have the “nerve” to “challenge that assertion” no matter how repeated, that climate science is “alarmist”. Science is a discipline that requires care, intelligence, training, and dedication and most climate scientists and scientific associations are not in a big conspiracy to persuade people of things that aren’t true.  As to catastrophists, they do exist, and I’m not sure they’re so very far off, but scientists are not catastrophists.  Since you are in the business of inflating a lot of hot air and cool clouds, you likely recognize the phenomenon of creating guilt by accusation and association.

Reply to this comment

By David (Fort Worth)
on August 18th, 2011

Excellent article! Keep it up—I love this site and what you’re trying to accomplish!

Reply to this comment

By melty (West Orange, NJ 07052)
on September 8th, 2011

Joe (August 6):  “it’s about the inherent uncertainties being greater than generally advertised. “

So….. could those uncertainties go in the other direction too?  IOW, could it in fact be much, _much worse than anticipated?  Why is the risk all in one direction, in your view?

Reply to this comment

By Doug Cotton (Sydney )
on January 23rd, 2012

If you wish to prove AGW valid then you would need to find an empirical experiment showing radiation from a cooler source (atmosphere) actually warming a warmer surface, contrary to proven physics as linked from my site

Reply to this comment

By Doug Cotton (Sydney)
on March 22nd, 2012

Please refer to my paper on any of these sites ...




Reply to this comment

By justin
on July 3rd, 2012

“Overall, the argument made in all of these papers… is extremely weak. What they do is show some data, then they show a very simple model with some free parameters that they tweak until they fit the data. They then conclude that their model is right. However, if the underlying model is wrong, then the agreement between the model and data proves nothing.”

Pot. Kettle. Black.  Hillarious.  I suppose the idiot stating this has a model that works better at predicting the weather than those propagandists at Hadley.

Reply to this comment

By Asashii Fustazi
on March 14th, 2013

all i know is that i like tropical weather, and all i know is that the earth has been alot hotter and colder without Mankind even coming close to causing it, and that el nina and el nino are a B!tch!!!

Reply to this comment

Name (required):
Email (required):
Enter the word "climate" in the box below:

[+] View our comment guidelines.

Please note: Comment moderation is enabled. Your comment will not appear until reviewed by Climate Central staff. Thank you for your patience.