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Discussion > "Climate communication" - what do you think?


he is implying a position the IPCC itself does not hold.

You claim that the IPCC position is that natural variation has stopped. This is utter nonsense. It's astonishing that you repeat this claim after I've pointed out - twice now - that the quotes from 'IPCC 2007' you provided above clearly indicate that a *combination* of natural variation and anthropogenic forcing is required to explain observed recent climate behaviour.

You then double down:

Natural variability is dialed in, and back out, as an explanation for various portions of the curve, which is indeed shown and predicted to rise monotonically. If one observes the IPCC projections, they all show monotonic projections with various rates of rise.

Here's a standard example of modelled simulations of C20th climate with and without anthropogenic forcings. The black curve represents observed temperatures. You can see that the multi-model mean in panel (a) is *not* monotonic - the interplay between natural and anthropogenic forcings is clearly evident even though it is an average of multiple runs.

Here is a detailed representation of the same model ensembles from AR4 under anthropogenic forcing, but now extended to 2020. Once again, *natural varibility* is very evident. At a guess, I'd say you've confused the centennial-scale multi-model means with the mass of highly variable individual runs.

This is the AR4 statement on the co-existence of natural variation with anthropogenic forcing in modern climate variability:

‘Climate change’ refers to a change in the state of the climate that can be identified (e.g., using statistical tests) by changes in the mean and/or the variability of its properties, and that persists for an extended period, typically decades or longer (see Glossary). Climate change may be due to internal processes and/or external forcings. Some external influences, such as changes in solar radiation and volcanism, occur naturally and contribute to the total natural variability of the climate system. Other external changes, such as the change in composition of the atmosphere that began with the industrial revolution, are the result of human activity. A key objective of this chapter is to understand climate changes that result from anthropogenic and natural external forcings, and how they may be distinguished from changes and variability that result from internal climate system processes.

Internal variability is present on all time scales. Atmospheric processes that generate internal variability are known to operate on time scales ranging from virtually instantaneous (e.g., condensation of water vapour in clouds) up to years (e.g., troposphere-stratosphere or inter-hemispheric exchange). Other components of the climate system, such as the ocean and the large ice sheets, tend to operate on longer time scales. These components produce internal variability of their own accord and also integrate variability from the rapidly varying atmosphere (Hasselmann, 1976). In addition, internal variability is produced by coupled interactions between components, such as is the case with the El-Niño Southern Oscillation (ENSO; see Chapters 3 and 8).

You are still relying on a mix of muddle and misrepresentation instead of coherent argument.

Jul 11, 2012 at 7:40 PM | Unregistered CommenterBBD

geronimo, it's so hard to get an answer to a simple question. I was beginning to think the framing of it was 'not even wrong'. So, if Harries is to be believed (and I see no reason why not) one of the CO2 bands is now saturated. Do the warmists agree? Surely it must be, or it would respond. So, how does that effect the 3.7 w/sqm/doubling? Reduce it? It must. Now, the response in the band which is not saturated. How much heat is that? Why is it not expressed in heat units? What is happening in the H2O part of the spectrum? These answer would be best evidence. I gather from the lack of follow-through that they are not the answers the warmists were looking for. I don't know why Richard B has not replied. He is not obliged to answer me. But again I take note of the lack of response.

(Nobody needs to respond to this with a chain of dodgy links. Just the answer to these questions or reason why they are wrongly framed will do nicely.)

Jul 11, 2012 at 8:56 PM | Registered Commenterrhoda


I dont see anything in AR4 about cosmic rays or the journey of the sun around the galaxy.
I dont see anything in AR4 about any role being played by ozone.

The Hockey stick:

This unspeakable piece of....... work is important because without it there would have been no Kyoto protocol and we would not be in the mess we are in today.

Jul 11, 2012 at 11:00 PM | Registered CommenterDung

... provided above clearly indicate that a *combination* of natural variation and anthropogenic forcing is required to explain observed recent climate behaviour.


... it is extremely unlikely that global climate change of the past 50 years can be explained without external forcing, and very likely that it is not due to known natural causes alone.

from the IPCC

Put a little bit of pressure and this guy changes his tack. He can't keep his story straight within the space of two comments.

If a "combination of natural variability and CO2" explains temperature changes, how come natural variability explains only the cooling and CO2 only explains the warming?

The models do not show multidecadal variability of any significance. The ups and downs seen occur over timescales of a few years at best, and represent the random short term noise present in a complex model. What longer scale variability they do capture amounts to a nothing. The long term trends are monotonic. Grasping this fact, of course, requires the reader to grasp the concept of what constitutes a trend, and noise, at all time scales.

Propagandists, by necessity, would have to have killed this capacity to begin what they do in the first place. So it is ok if BBD doesn't understand all this.

Jul 12, 2012 at 12:09 AM | Registered Commentershub

In the hope of re-railing the thread, has everyone seen the latest 'on hold' review of climate scientist and communicator David Karoly's review of his pal's book:

Mann [who is an expert in everything related to climate science except statistics] never imagined that his research would push him out of the ivory towers of academia into the cut-and-thrust world of politics, commentators, and lobbyists. But it certainly did, and this book describes his experiences over the last two decades as a climate scientist, as a communicator, and as a target of frequent attacks. Mann was subjected to what he describes as the ‘Serengeti strategy’, in which predators ‘look for the most vulnerable animal at the edge of a herd’. In his case the predators were climate change ‘confusionists’, politicians and commentators who wish to confuse the public understanding of climate change science and delay action on reducing industrial emissions of green-house gases.

I always thought Karoly would make a good 'zebra of the week'. He was already wounded during the hunt for the small Gergis group. And now he comes back for more action. And now he's started running already.

The WUWT pride is on him. But why do they behave like that? I mean the zebras who want some climate communication; why do they always end up running away, and where do they think they can hide in the Serengeti?

Jul 12, 2012 at 4:42 AM | Unregistered CommentersHx


If a "combination of natural variability and CO2" explains temperature changes, how come natural variability explains only the cooling and CO2 only explains the warming?

You just can't see it can you? First off, what if it's not all natural? What about sulphates from Chinese coal, for example? Then as for the natural forcings, how about the historically quiet Solar Cycle 24? And predominantly La Niña conditions over the last decade? Deep ocean mixing?

All these things can offset warming from CO2 forcing. For a while. An unusual combination of events doesn't constitute the killer argument you seem to think.

Put a little bit of pressure and this guy changes his tack. He can't keep his story straight within the space of two comments.

The usual dishonesty.

Jul 12, 2012 at 10:41 AM | Unregistered CommenterBBD

Remember, to dispute the primary role of CO2 in causing energy to accumulate in the climate system you must

- deny the physics of radiative forcing, aka 'the greenhouse effect' *and*

- provide solid evidence for an alternative forcing sufficient to explain observed warming


All these things can offset warming from CO2 forcing.

Who's doing the denying?


An unusual combination of events doesn't constitute the killer argument you seem to think.


If something 'unusual' happened and toppled your theory and you termed these things unusual in your explanation, *after* they happened, it means your theory is wrong.

Keyword: parsimony

I wonder, why doesn't BBD spend time at BBD-a-scape?

Jul 12, 2012 at 11:38 AM | Registered Commentershub

It doesn't 'topple the theory'. As explained above.

Keyword: denial.

Jul 12, 2012 at 12:51 PM | Unregistered CommenterBBD

It says the theory proposer may take into account things he never mentioned before and that the theory is effectively unfalsifiable for that reason. It weakens the theory, which must be defended with epicycles and handwaving.

Jul 12, 2012 at 1:05 PM | Registered Commenterrhoda

Jul 11, 2012 at 8:56 PM | rhoda

Hi rhoda

Sorry for slow response, I've just been busy. I've replied on your "What's my best evidence" thread as this topic seems more appropriate for that thread, so I think it's best we move it there if that's OK.



Jul 12, 2012 at 1:27 PM | Registered CommenterRichard Betts

Jul 11, 2012 at 11:00 PM | Dung

I dont see anything in AR4 about cosmic rays or the journey of the sun around the galaxy.
I dont see anything in AR4 about any role being played by ozone.

Hi Dung

For IPCC discussion of both cosmic rays and ozone, please see AR4 WG2 chapter 2 sections 2.3.6 and 2.7.1 and table 2.12 and fig2 2.20, 2.21 and 2.23



Jul 12, 2012 at 1:34 PM | Registered CommenterRichard Betts


It says the theory proposer may take into account things he never mentioned before

Same strawman as shub: *nobody* ever said warming would be monotonic. Nobody ever said natural variation would stop. Shub was talking his usual uninformed, biased crap. One does have to bear this in mind. Closer reading of my responses might be helpful too.

This is getting tiresome.

Jul 12, 2012 at 2:41 PM | Unregistered CommenterBBD

Richard you have commented on my post to BBD but ignored my post to you?

No wonder I missed the discussion on cosmic rays:

Least certain, and under ongoing debate as discussed in the TAR, are indirect effects induced by galactic cosmic rays (e.g., Marsh and Svensmark, 2000a,b; Kristjánsson et al., 2002; Sun and Bradley, 2002).2.7.1

By 2007 Svensmark had already performed experiments in his own lab confirming that large molecules created by cosmic rays entering our atmosphere, could seed low clouds --> cooling.
A team of 50 scientists had already been created to repeat these experiments at CERN.
It has been know for centuries that temperature had a very good correlation with sunspots but the mechanism was not understood.
Svensmark's work provided the mechanism and empirical proof to back it up, his work is of massive importance but the IPCC ignored it.

Jul 12, 2012 at 2:46 PM | Registered CommenterDung


Laken & Calogovic (2011)

Although over centennial and greater timescales solar variability may be one of the most influential climate forcing agents, the extent to which solar activity influences climate over shorter time periods is poorly understood. If a link exists between solar activity and climate, it is likely via a mechanism connected to one (or a combination) of the following parameters: total solar irradiance (TSI), ultraviolet (UV) spectral irradiance, or the galactic cosmic ray (GCR) flux. We present an analysis based around a superposed epoch (composite) approach focusing on the largest TSI increases and decreases (the latter occurring in both the presence and absence of appreciable GCR reductions) over daily timescales. Using these composites we test for the presence of a robust link between solar activity and cloud cover over large areas of the globe using rigorous statistical techniques. We find no evidence that widespread variations in cloud cover at any tropospheric level are significantly associated with changes in the TSI, GCR or UV flux, and further conclude that TSI or UV changes occurring during reductions in the GCR flux are not masking a solar-cloud response. However, we note the detectability of any potential links is strongly constrained by cloud variability.

Sloan & Wolfendale (2011)

A search has been made for a contribution of the changing cosmic ray intensity to the global warming observed in the last century. The cosmic ray intensity shows a strong 11 year cycle due to solar modulation and the overall rate has decreased since 1900. These changes in cosmic ray intensity are compared to those of the mean global surface temperature to attempt to quantify any link between the two. It is shown that, if such a link exists, the changing cosmic ray intensity contributes less than 8% to the increase in the mean global surface temperature observed since 1900.

Jul 12, 2012 at 3:51 PM | Unregistered CommenterBBD


Both papers quoted are behind paywalls which is really helpful.

Laken & Calogovic (2011) seems to be irrelevant since daily changes in temp = weather not climate. However I take the following from the available text:

Although over centennial and greater timescales solar variability may be one of the most influential climate forcing agents.

However, we note the detectability of any potential links is strongly constrained by cloud variability.

In addition the above paper talks about tropospheric cloud which is anything up to 17/20 km. three graphs are shown labeled as high cloud, medium cloud and low cloud but there is no definition of "low cloud". It is only very low cloud that cools the planet.

Sloan & Wolfendale (2011):


Search for a connection between the variation in cosmic rays and the global temperature. ► No connection could be found

However within the brief info outside the paywall there is a graph showing falling levels of cosmic ray impacts with rising temperature?
Fewer cosmic rays = less low cloud = warming.

Jul 12, 2012 at 5:07 PM | Registered CommenterDung


'Shorter time periods' per L&C includes the recent warming attributed to CO2 forcing. Long periods means eg the Holocene. Solar influence on climate means stuff like Milankovitch forcing. The study shows that no solar-climate link operating over *shorter* time periods can be demonstrated. In other words, it's one of the ever-growing stack that finds no evidence supporting the Svensmark hypothesis. We are back to CO2 again.

I can't find a downloadable pdf of L&C but S&W is here.

I can see why SW figs 1 & 2 might have confused you but it is explained in the paper itself. The apparent relationship breaks down since the mid-C20th. Once again, there's *no evidence* to support the Svensmark hypothesis:

Figure 2 shows the data from figure 1 with 11 year smoothing applied to illustrate the long term trends (removing the effects of the solar cycle). It can be seen that the CR rate decreased rapidly from 1880 to 1950 when the temperature rise was relatively small. On the other hand the CR rate changed little from 1950-2000 when the temperature rise was bigger (Lockwood and Fr¨ohlich 2007). Hence the variation of the temperature with time matches poorly the variation of the CR rate with time. Such a match would be expected if CR played a significant role in global warming. It can be seen that the CR rate decreased in intensity by 16% from 1880 to 1952 during which time the mean global temperature rose by 0.3◦ while from 1952 to 2000 the CR rate decreased by 3% and the temperature rose by 0.6◦.

Figure 3 shows the values of the temperature anomalies T, plotted as a function of CR rate, each taken from figure 2. It can be seen that in the early part of the 20th century there was a roughly linear relationship between the two. Linear fits were made to the data in various time ranges starting from 1886. The slopes, dT/dCR, varied in values from -0.008 to -0.022 ◦C per % change in the Climax NM rate as the end year of the fit varies from the year 1930 to 2000. Cycling through each end year in this time range, the mean value of dT/dCR was -0.016◦C per % change in the Climax NM rate with root mean square deviation of the readings of 0.003. If there is a causal link between CR and the global temperature, this value of dT/dCR implies that the 3% change in CR rate observed since 1952 would give a temperature change of 0.05◦C. The observed change in temperature since 1952 is 0.6◦C. Hence less than 8% of the observed rise in temperature since 1952 can be ascribed to CR. We take this as an upper limit on the contribution of CR to GW.

Jul 12, 2012 at 6:12 PM | Unregistered CommenterBBD

Jul 12, 2012 at 6:24 PM | Registered CommenterPhilip Richens


We are not back to CO2. There happens to be an 800 years lag between temperature and CO2 and you know which one lags I am sure.
I will read up on cosmic ray correlation.
Unlike the Grennhouse Gas theory, the Svensmark theory is not going to be discernable on a day to day basis or even a centenial basis, there are too many other things going on; recently the sun's south pole reversed but the north pole did not so the sun currently has two north poles and 4 south poles. The sun is leaving a galactic spiral arm and so cosmic rays will continue to decrease over the long term but will still be affected by solar wind strength and Earth orbit changes in the short term.

Jul 12, 2012 at 10:12 PM | Registered CommenterDung

I posted in "Unthreaded" about science communications and the new thread at Judith Curry's place. Perhaps I should have posted here, since any discussion should better take place here than in "Unthreaded" but I did not want my acidic remark about activist scientists to be associated with what Richard Betts does in terms of "science communications." I have a low level of trust (none at all) toward anything uttered by Michael Mann, David Karoly, Jim Hansen et al. They so obviously have their own socio-political "axes to grind" that go beyond science.

fwiw, I have a much higher level of trust toward anything Richard or Tamsin et al might say about their own scientific research and related matters. They do not seem to be approaching the public with any of the evident biases of the 3 people named in my first paragraph. That does not mean I will agree with every particular policy recommendation if they were to make some, but I would not automatically think that I was being "sold" a political agenda under the guise of a scientific agenda, as I would with the likes of Hansen, Mann, and Karoly.

However, I do share many concerns about the IPCC reports and processes with other commentators at BH. I don't think that the processes for AR5 have been reformed sufficiently. Perhaps the activist-scientists like Karoly do us all a favor by making us even more watchful and guarded!

So, yes, when scientists start crossing lines from talking about "just the science" to policy recommendations, trust may be imperilled. It's a difficult issue about expertise, democracy, and public policy but I think it has a lot to do with the fact that any policy recommendations really are fraught with all kinds of VALUES and belief agendas which go far beyond the core scientific issues.

Jul 13, 2012 at 5:47 AM | Registered CommenterSkiphil


If you want to believe in an unsupported hypothesis (Svensmark) instead of accepting a theory (CO2-forced AGW) for which vast amounts of supporting evidence exists, that is your privilege.

We are not back to CO2. There happens to be an 800 years lag between temperature and CO2 and you know which one lags I am sure.

CO2, CH4 and water vapour are GHG feedbacks to orbital (Milankovitch) forcing. Of *course* there's a lag. Do you not know that nobody suggests that CO2 is the driver of glacial terminations? You need to stop getting your 'information' from 'sceptic' blogs.

Jul 13, 2012 at 8:17 AM | Unregistered CommenterBBD


I have tried to get Spartacus over here but failed however in relation to the 200 ppm saturation point for CO2 he writes:

Anyone who has done analytical chemistry knows the spectroscopic phenomenon of 'self-absorption', absorption of internally-generated EM energy by unexcited molecules. CO2 in air is well into that mode at ~200 ppm.

Illuminate the lower atmosphere with IR energy in the 4 and 14 micron bands and it excites CO2 molecules that would normally absorb thermal radiation from above. That increases DOWN emissivity so more IR in those bands arrives at the Earth's surface. This switches off the states which, when activated by kinetic energy, would emit that radiation.

The same applies to all the other GHGs. Much IR emission from the Earth is shifted to the 'atmospheric window'. Total GHE settles at a constant level. There can be no CO2-AGW. No amount of computer modelling can get over this basic fact.

Could you comment?

Jul 16, 2012 at 12:07 PM | Unregistered CommenterDung

To return to the original point of this thread, which was my question about my posting here at Bishop Hill, the slides from my presentation can be found here

PS. Dung, the role of CO2 as a greenhouse gas does not rely on computer modelling. We've already been through experimental and observational evidence that anthropogenic CO2 rise is affecting the radiation balance of the planet, both here and on Rhoda's "Where's my best evidence?" thread.

Jul 17, 2012 at 11:14 AM | Registered CommenterRichard Betts

..and we came to no certain conclusion because the work was not followed through to its end. What we got was a photo of a smoking gun produced by the prosecution when the real gun should have been in evidence. Now why didn't Harries follow through? Was it because he would have had to admit saturation in one waveband? Was it because he would have had to contradict the 3.7 watts figure? Or was it for some entirely innocent reason?

Jul 17, 2012 at 11:22 AM | Registered Commenterrhoda


It may be that it was a simple mistake for you to write:

Any responses to those points, or indeed any other thoughts, would be welcome.

because that is the phrase I understood to mean that I could ask you questions in this thread. Your time is far more valuable than mine but I have just as much frustration as you when time that I have spent has been wasted. I estimate that 80% - 90% of the questions I have raised with you have been ignored or as in the above recent post, simply shrugged off.
I do not have your in depth scientific knowledge and so my questions should be easy for you to answer. However if it is the case that you really dont have time to engage with someone like me, I would rather you said so up fron so that I can better use my time.

Jul 17, 2012 at 2:06 PM | Registered CommenterDung

The slides from Richard's talk are worth a look - they portray quite an accurate picture I think:

Who are the contributors to climate sceptic blogs?

Very wide range of understanding and opinions:
Some appear to be incurably cynical of the entire concept of man-made global warming
Some accept that warming is happening and there is a human contribution, but are unconvinced that it is a significant problem
Some have little in-depth knowledge of the science
Some are well-informed, & read (& occasionally find errors in!) scientific papers. Some are scientists themselves

What are the attitudes towards climate scientists on sceptic blogs?

Undercurrent of mistrust towards climate scientists, eg:
Perceptions / accusations of malpractice / incompetence, esp. through Climategate / Hockey stick affairs
Perceived political motivations – climate science seen as closely tied to Green or left-wing politics, or as part of government control & taxation
Seen as scaremongering in order to gain funding
Feelings of marginalisation – excluded from discussion
Welcome discussion with scientists (sceptics often stonewalled)
Often have genuine questions about the science and like to hear the answers
Arrogant, impatient attitudes tend to send the discussion of the rails
A civil attitude generally promotes a response in kind

Jul 23, 2012 at 5:45 PM | Registered CommenterPaul Matthews