Guest Post by Willis Eschenbach
In the leaked version of the upcoming United Nations Intergovernmental Panel on Climate Change (UN IPCC) Fifth Assessment Report (AR5) Chapter 1, we find the following claims regarding volcanoes.
The forcing from stratospheric volcanic aerosols can have a large impact on the climate for some years after volcanic eruptions. Several small eruptions have caused an RF for the years 2008−2011 of −0.10 [–0.13 to –0.07] W m–2, approximately double the 1999−2002 volcanic aerosol RF.
and
The observed reduction in warming trend over the period 1998–2012 as compared to the period 1951–2012, is due in roughly equal measure to a cooling contribution from internal variability and a reduced 2 trend in radiative forcing (medium confidence). The reduced trend in radiative forcing is primarily due 3 to volcanic eruptions and the downward phase of the current solar cycle.
Now, before I discuss these claims about volcanoes, let me remind folks that regarding the climate, I’m neither a skeptic nor am I a warmist.
I am a climate heretic. I say that the current climate paradigm, that forcing determines temperature, is incorrect. I hold that changes in forcing only marginally and briefly affect the temperature. Instead, I say that a host of emergent thermostatic phenomena act
quickly to cool the planet when it is too warm, and to warm it when it is too cool.
One of the corollaries of this position is that the effects of volcanic eruptions on global climate will be very, very small. Although I’ve demonstrated this before, Anthony recently pointed me to an updated volcanic forcing database, by Sato et al. Figure 1 shows the amount of forcing from the historical volcanoes.
Figure 1. Monthly changes in radiative forcing (downwelling radiation) resulting from historical volcanic eruptions. The two large recent spikes are from El Chichon (1983) and Pinatubo (1992) eruptions. You can see the average forcing of -0.1 W/m2 from 2008-2011 mentioned by the IPCC above. These are the equilibrium forcings Fe, and not the instantaneous forcing Fi.
Note that the forcings are negative, because the eruptions inject reflective aerosols into the stratosphere. These aerosols reflect the sunlight, and the forcing is reduced. So the question is … do these fairly large known volcanic forcings actually have any effect on the global surface air temperature, and if so how much?
To answer the question, we can use linear regression to calculate the actual effect of the changes in forcing on the temperature. Figure 2 shows the HadCRUT4 monthly global surface average air temperature.
Figure 2. Monthly surface air temperatures anomalies, from the HadCRUT4 dataset. The purple line shows a centered Gaussian average with a full width at half maximum (FWHM) of 8 years.
One problem with doing this particular linear regression is that the volcanic forcing is approximately trendless, while the temperature has risen overall. We are interested in the short-term (within four years or so) changes in temperature due to the volcanoes. So what we can do to get rid of the long-term trend is to only consider the temperature variations around the average for that historical time. To do that, we subtract the Gaussian average from the actual data, leaving what are called the “residuals”:
Figure 3. Residual anomalies, after subtracting out the centered 8-year FWHM gaussian average.
As you can see, these residuals still contain all of the short-term variations, including whatever the volcanoes might or might not have done to the temperature. And as you can also see, there is little sign of the claimed cooling from the eruptions. There is certainly no obvious sign of even the largest eruptions. To verify that, here is the same temperature data overlaid on the volcanic forcing. Note the different scales on the two sides.
Figure 4. Volcanic forcing (red), with the HadCRUT4 temperature residual overlaid.
While some volcanoes line up with temperature changes, some show increases after the eruptions. In addition, the largest eruptions don’t seem correlated with proportionately large drops in temperatures.
So now we can start looking at how much the volcanic forcing is actually affecting the temperature. The raw linear regression yields the following results.
R^2 = 0.01 (a measure from zero to one of how much effect the volcanoes have on temperature) "p" value of R^2 = 0.03 (a measure from zero to one how likely it is that the results occurred by chance) (adjusted for autocorrelation). Trend = 0.04°C per W/m2, OR 0.13°C per doubling of CO2 (how much the temperature varies with the volcanic forcing) "p" value of the TREND = 0.02 (a measure from zero to one how likely it is that the results occurred by chance) (adjusted for autocorrelation).
So … what does that mean? Well, it’s a most interesting and unusual result. It strongly confirms a very tiny effect. I don’t encounter that very often in climate science. It simultaneously says that yes, volcanoes do affect the temperature … and yet, the effect is vanishingly small—only about a tenth of a degree per doubling of CO2.
Can we improve on that result? Yes, although not a whole lot. As our estimate improves, we’d expect a better R^2 and a larger trend. To do this, we note that we wouldn’t expect to find an instantaneous effect from the eruptions. It takes time for the land and ocean to heat and cool. So we’d expect a lagged effect. To investigate that, we can calculate the R^2 for a variety of time lags. I usually include negative lags as well to make sure I’m looking at a real phenomenon. Here’s the result:
Figure 5. Analysis of the effects of lagging the results of the volcanic forcing.
That’s a lovely result, sharply peaked. It shows that as expected, after a volcano, it takes about seven-eight months for the maximum effects to be felt.
Including the lag, of course, gives us new results for the linear regress, viz:
R^2 = 0.03 [previously 0.01] "p" value of R^2 = 0.02 (adjusted for autocorrelation) [previously 0.03] Trend = 0.05°C per W/m2, OR 0.18 ± 0.02°C per doubling of CO2 [previously 0.13°C/doubling] "p" value of the Trend = 0.001 (adjusted for autocorrelation). [previously 0.02]
As expected, both the R^2 and the trend have increased. In addition the p-values have improved, particularly for the trend. At the end of the day, what we have is a calculated climate sensitivity (change in temperature with forcing) which is only about two-tenths of a degree per doubling of CO2.
Here are the conclusions that I can draw from this analysis.
1) The effect of volcanic eruptions is far smaller than generally assumed. Even the largest volcanoes make only a small difference in the temperature. This agrees with my eight previous analyses (see list in the Notes). For those who have questions about this current analysis, let me suggest that you read through all of my previous analyses, as this is far from my only evidence that volcanoes have very little effect on temperature.
2) As Figure 5 shows, the delay in the effects of the temperature is on the order of seven or eight months from the eruption. This is verified by a complete lagged analysis (see the Notes below). That analysis also gives the same value for the climate sensitivity, about two tenths of a degree per doubling.
3) However, this is not the whole story. The reason that the temperature change after an eruption is so small is that the effect is quickly neutralized by the homeostatic nature of the climate.
Finally, to return to the question of the IPCC Fifth Assessment Report, it says:
There is very high confidence that models reproduce the more rapid warming in the second half of the 20th century, and the cooling immediately following large volcanic eruptions.
Since there is almost no cooling that follows large volcanic eruptions … whatever the models are doing, they’re doing it wrong. You can clearly see the volcanic eruptions in the model results … but you can’t see them at all in the actual data.
The amazing thing to me is that this urban legend about volcanoes having some big effect on the global average temperature is so hard to kill. I’ve analyzed it from a host of directions, and I can’t find any substance there at all … but it is widely believed.
I ascribe this to an oddity of the climate control system … it’s invisible. For example, I’ve shown that the time of onset of tropical clouds has a huge effect on incoming solar radiation, with a change of about ten minutes in onset time being enough to counteract a doubling of CO2. But no one would ever notice such a small change.
So we can see the cooling effect of the volcanoes where it is occurring … but what we can’t see is the response of the rest of the climate system to that cooling. And so, the myth of the volcanic fingerprints stays alive, despite lots of evidence that while they have large local effects, their global effect is trivially small.
Best to all,
w.
PS—The IPCC claims that the explanation for the “pause” in warming is half due to “natural variations”, a quarter is solar, and a quarter is from volcanoes. Here’s the truly bizarre part. In the last couple decades, using round numbers, the IPCC predicted about 0.4°C of warming … which hasn’t happened. So if a quarter of that (0.1°C) is volcanoes, and the recent volcanic forcing is (by their own numbers) about 0.1 W/m2, they’re saying that the climate sensitivity is 3.7° per doubling of CO2.
Of course, if that were the case we’d have seen a drop of about 3°C from Pinatubo … and I fear that I don’t see that in the records.
They just throw out these claims … but they don’t run the numbers, and they don’t think them through to the end.
Notes and Data
For the value of the forcing, I have not used the instantaneous value of the volcanic forcing, which is called “Fi“. Instead, I’ve used the effective forcing “Fe“, which is the value of the forcing after the system has completely adjusted to the changes. As you might expect, Fi is larger than Fe. See the spreadsheet containing the data for the details.
As a result, what I have calculated here is NOT the transient climate response (TCR). It is the equilibrium climate sensitivity (ECS).
For confirmation, the same result is obtained by first using the instantaneous forcing Fi to calculate the TCR, and then using the TCR to calculate the ECS.
Further confirmation comes from doing a full interative lagged analysis (not shown), using the formula for a lagged linear relationship, viz:
T2 = T1 + lambda (F2 – F1) (1 – exp(-1/tau)) + exp(-1/tau) (T1 – T0)
where T is temperature, F is forcing, lambda is the proportionality coefficient, and tau is the time constant.
That analysis gives the same result for the trend, 0.18°C/doubling of CO2. The time constant tau was also quite similar, with the best fit at 6.4 months lag between forcing and response.
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In this case it’s the Sato paper, which provides a dataset of optical thicknesses “tau”, and says:
The relation between the optical thickness and the forcings are roughly (See “Efficacy …” below):
instantaneous forcing Fi (W/m2) = -27 τ
adjusted forcing Fa (W/m2) = -25 τ
SST-fixed forcing Fs (W/m2) = -26 τ
effective forcing Fe (W/m2) = -23 τ
And “Efficacy” refers to
Hansen, J., M. Sato, R. Ruedy, L. Nazarenko, A. Lacis, G.A. Schmidt, G. Russell, et al. 2005. Efficacy of climate forcings. J. Geophys. Res., 110, D18104, doi:10.1029/2005/JD005776.
Forcing Data
For details on the volcanic forcings used, see the Sato paper, which provides a dataset of optical thicknesses “tau”, and says:
The relation between the optical thickness and the forcings are roughly (See “Efficacy …” below):
instantaneous forcing Fi (W/m2) = -27 τ
adjusted forcing Fa (W/m2) = -25 τ
SST-fixed forcing Fs (W/m2) = -26 τ
effective forcing Fe (W/m2) = -23 τ
And “Efficacy” refers to
Hansen, J., M. Sato, R. Ruedy, L. Nazarenko, A. Lacis, G.A. Schmidt, G. Russell, et al. 2005. Efficacy of climate forcings. J. Geophys. Res., 110, D18104, doi:10.1029/2005/JD005776.
(Again, remember I’m using their methods, but I’m not claiming that their methods are correct.)
Future Analyses
My next scheme is that I want to gin up some kind of prototype governing system that mimics what it seems the climate system is doing. The issue is that to keep a lagged system on course, you need to have “overshoot”. This means that when the temperature goes below average, it then goes above average, and then finally returns to the prior value. Will I ever do the analysis? Depends on whether something shinier shows up before I get to it … I would love to have about a dozen bright enthusiastic graduate students to hand out this kind of analysis to.
I also want to repeat my analysis using “stacking” of the volcanoes, but using this new data, along with some mathematical method to choose the starting points for the stacking … which turns out to be a bit more difficult than I expected.
Previous posts on the effects of the volcano.
Prediction is hard, especially of the future.
Pinatubo and the Albedo Thermostat
Dronning Maud Meets the Little Ice Age
New Data, Old Claims about Volcanoes
Volcanoes: Active, Inactive and Interactive
Stacked Volcanoes Falsify Models
Thanks Anthony.
Stratospheric aerosols cut back on incoming solar radiation. Values of 7% reduction or higher have been measured. This is widely accepted as being a factor in causing global cooling for 2 to 3 years after a major eruption. Some eruptions have been estimated to throw aerosols to 80,000 or even 120,000 feet high into our atmosphere. While ash and aerosols (sulfate converted from O2) typically falls out from low level eruptions in days or weeks, those that make it into the stratosphere have a lifetime of a few years. While there, they serve to cool the atmosphere and surface (although with regional variances) and when they fall out to serve as nuclei for ice and water droplet clouds and precipitation (rain and snow). Remember the big Midwest flood of 1993 and the huge snows of March 1993 to the winter of 1993/94 and 1995/96
Dr. Richard Keen, who lives in the beautiful Colorado Rockies and is both a weather observer and astronomical expert has been using eclipses to measure this effect. He found the thickness varied and estimated the effect on temperatures
The above is part of the article by Joe D’Aleo of Weatherbell. Again to get the whole article google The real climate drivers -ocean and solar cycles amplified by levels of volcanism.
Many graphs will be found.
I have just seen Eschenbach’s charming post.
I have never made the claims that you say i have because they are total nonsense. Having been taught this subject formally, I hope that I do not make those sort of mistakes.
I was asked to write a post because you wrote a post on filtering and statistics that was completely wrong. I did not go out of my way to be offensive in that post, which was written at a very elementary level,, but it was completely apparant from what I wrote that filtering, as you had done in the bandwidth of a signal, will alter the correlation functions.
I would point out that these sort of mistakes stem from a failure to understand the theory of the subject rather than an ability to do something in “R”.
You ask me what is wrong with your model? For a start, you apply a first order ARMA process to signal when there is subtantial evidence that the temperature signal does not have an autocorrelation function that conforms to that process, Therefore you cannot apply this model.
Second, you have failed to consider any possibilityof non-linear effects in your model.
Third, you have not performed any sort of proper analysis of uncertainty in your analysis, which you should, The errors in the type of an analysis you have performed are potentially large. Your claim that it accounts for 90% of the energy in the signal (I presume that you really mean this? Are you familiar with Parseval’s theorem?) is inadequate to clain that that you have identified the system in question.
Finally you ask for help from some MSc students. If they are properly taught, I have no doubt that they form an opinion on your mathematical expertise.
richardscourtney: “Thankyou for that example. I did not know of it.”
You’re welcome. Although I encountered it in the kitchen, personnel of a utility-boiler manufacturer I once had as a client referred to the phenomenon as “departure from nucleate boiling” and were wont to discuss “departure-from-nucleate-boiling ratio.”
“In your example the formation of ‘marbles’ acts to reduce evapouration rate so acts as a negative feedback on evapouration.” As far as “feedback” goes, I guess my taxonomy is different from yours, but I doubt that either of us would gain much from further pursuing that discussion.
Willis or somebody else with good science-fu… can somebody help the liberal arts major here?
It seems to me (but sometimes my ideas accidentally violate the laws of thermodynamics), that part of the equilibrium might have something to do with axial tilt? No, I’m not trolling, hear me out for a second, and then illuminate/slap-me-around as needed:
You get something like a volcano: it’s going to produce a lot of localized cooling. But then it becomes winter, and the local area gets dropped even further below what the volcano would be doing…end result being more heat circulation from the rest of the globe, bang, it’s evened out, resulting in, as measured globally the forcing mechanism is destroyed at a global energy cost that is distinct, but miniscule.
I’m assuming the 305k ocean-temp limit combined with lots and lots of summer sunlight handles the other side of said equation, but… I was a history major. You wanna know why Hugh de Beaux kidnapped Mary of Siciliy in 1350, I’m your dude…. this stuff, not so much (but interested).
What am I not getting here? Thanks in advance.
Bill says: September 22, 2013 at 1:28 pm
Willis, how does your governor theory explain ice ages?
_____________________________________
I know this is slightly OT for this thread, but it is an interesting and related topic.
It is said that Milankovitch Cycles can vary the insolation at latitudes above 60N by as much as 20%. That is quite possibly enough change in insolation to generate an Ice Age, as you sure would not get an ice sheet to grow over London with our current insolation levels. So something must be stopping the insolation.
Here is a common Milankovitch Cycle vs Temperature graph. Plus a graph of Ice Ages. I am not sure whether the match between calculated insolation and the temperature is significant mathematically, but the layman’s ‘one-eyed squint’ method says the correlation has some merit.
http://www.climatedata.info/Forcing/Forcing/milankovitchcycles_files/BIGw02-milankovitch-and-temperature.gif.gif
http://upload.wikimedia.org/wikipedia/commons/thumb/c/c9/Co2_glacial_cycles_800k.png/800px-Co2_glacial_cycles_800k.png
But if Milankovitch Cycles were responsible for N hemisphere Ice Ages, then I would presume that the southern hemisphere must have equal and opposite glaciation periods. Is this so? I was unable to find any info on this.
So in answer to Bill’s question:
The Tropical Cumulus theory will probably work well as a regulator for the temperature of the system over long periods of time. But if someone turns the Sun off in the N hemisphere (a negative Milankovitch Cycle), its going to get cold.
Willis, excellent pose with good scientific analysis unlike AR 5
“…period 1951–2012, is due in roughly equal measure to a cooling contribution from internal variability and a reduced 2 trend in radiative forcing (medium confidence). The reduced trend in radiative forcing is primarily due 3 to volcanic eruptions and the downward phase of the current solar cycle.”
Strange the same suspects denied these factors before when there was an increase in temperature and now admit to these when temperatures are flat or downward.
Furthermore these are not new considerations (they have been mentioned before by skeptics and ignored) and if the computer models did not consider them it further confirms the flaws in the models. Let’s face it, the models are a total fabrication using preconceived, erroneous notions and bear no resemblance to science or reality.
eric1skeptic says:
September 23, 2013 at 2:27 am
I posted the link in my first comment on the topic, & subsequently, as would have been easy to check.
Greg Goodman:
I am replying to your post at September 23, 2013 at 7:19 am which says in total
NO!
I do not know how I could be more clear than I have been in my series of attempts to explain this matter in this thread.
A negative feedback – be it linear or otherwise – reduces the magnitude of an effect.
So, for simplistic illustration, if a heat input causes warming of 2.0K per hour then a negative feedback of 0.5 will reduce that rate of rise to 1.0K per hour.
A Reversal Effect is induced when the system passes a threshold. It is larger and has opposite result to the original effect. So, when the Reversal Effect initiates the combination of the original effect and the reversal Effect provides the opposite of the original effect.
In the simplistic illustration, the heat input causes warming of 2.0K per hour but when the Reversal Effect initiates the system starts to COOL although the heat input is continued. This has nothing to do with overshoot because it has nothing to do with feedbacks on the original effect .
It happens because an ADDITIONAL effect initiates in the system.
Thunder clouds and storms are the additional initiated effect of the Eschenbach Effect.
Cirrus clouds are the additional initiated effect of the R&C Effect.
In other words, the system becomes a different system when a Reversal Effect initiates.
Richard
RC Saumarez:
In your less than “charming” post at September 23, 2013 at 8:24 am you say
I can accept that because we all have similar hopes. I hope to win the lottery.
Richard
Willis is trying to show ever so hard that volcanic forcing is much less, then all the past evidence shows to the contrary. He is entitled to his opinion and methold of trying to prove it, although it is not convincing to me.
Look at what happened to the temperatures following the Mt. Pinatubo eruption, they went down in the face of an El Nino.
Each volcanic eruption is different in regards to it’s location, composition of what it ejects into the air, height/amounts of material it ejects into the air making a volcano /temperature correlation amost impossible to obtain, not to mention other climatic items acting in concert or against the volcanic climatic effects.
Willis says and it it correct in a sense( but not really) the following: a host of emergent thermostatic phenomena act quickly to cool the planet when it is to warm, and to warm it when it is to cool.
If true 100% of the time as you convey more or less; reconcile that statement with the fact the earth has had many ABRUPT climatic changes in the past, and have shifted from a glacial state to an inter glacial state many times in the past. Apparently that statement does not hold up under all circumstances for if it did the climate would never have abrupt climate swings in temperature both up and down, or vary from a glacial to an inter glacial state..
Something else has to be at work here.
The three dryas periods(oldest,old and younger) and the 8200 years ago abrupt cooling period are some examples of rapid climatic temperature drops, which run counter to your statement.
Is your analysis in conflict with the following study?
Global surface-temperature responses to major volcanic eruptions
SEAR, KELLY, JONES & GOODESS
Nature 330, 365 – 367 (26 November 1987)
…In a previous study5 it was shown that significant surface cooling occurs over the landmasses of the Northern Hemisphere in the first few months after a major eruption in that hemisphere. Here we extend that work using new surface-air temperature compilations based on land and marine data6 for both the Northern and Southern Hemispheres. Our results indicate that major Northern Hemisphere eruptions have an immediate effect on the Northern Hemisphere average surface temperature but little or no effect on the Southern Hemisphere average. Southern Hemisphere eruptions affect both Southern and Northern Hemisphere temperatures after a lag of between six months and a year.
http://books.google.com/books?id=3me16ll_TRkC&pg=PP152&lpg=PP152&dq=39.5+34.3+bushels+acre&source=bl&ots=kl-4vVGj5c&sig=87fK59G59caccvIgP5J6GlrtRUA&hl=en&sa=X&ei=f2RAUsL5HYiwigKN8oGIDQ&ved=0CE4Q6AEwBQ#v=onepage&q=39.5%2034.3%20bushels%20acre&f=false
Checking I see that it was 39.5 bu/A in 1990 & 34.3 in 1991, then back up in ’92, so I was off by a year. My mistake; yet price did go way up in ’92. USDA marketing year differs from international, but the error appears to have been mine.
However the fact remains that globally yield fell in 1992, as shown above, from 2.6 T/ha in ’91 to 2.5 T/ha. It’s noticeable, to me at least, even in Willis’ graph. I believe it went up for corn, but didn’t check other crops.
Willis Eschenbach says:
September 23, 2013 at 7:02 am
Manly & scientific of you, but please explain why you disagree with the world wheat yield data I posted from the USDA’s FAS, reposted here:
http://www.fas.usda.gov/grain/circular/2010/05-10/grainfull05-10.pdf
Total Wheat and Coarse Grains
Millions of Metric Tons/Hectares
Year Area Harvested Yield Production
1990/91 549.0 2.6 1,417.5
1991/92 546.3 2.5 1,355.5
Thanks.
WIllis if volcanos made no contributions to the Maunder Minimum and Dalton Minimum ,you are then adding more evidence that is was caused by direct changes in various solar parameters rather then perhaps a secondary factor associated with the direct solar changes in solar parameters.
In this case volcanism being an associated secondary factor asociated with prolonged solar minimum periods,(which many studies show to be the case) which enhances any change in the climate due to direct solar vairiations, which you also do not feel is real ,despite once again past history showing very clearly that is not the case.
Willis something has caused the climate to change in abrupt ways and from glacial to inter glacial states. I say, it is changes in the sun and all the associated secondary effects which phase into either a warming /or cooling of the climate, if not you tell me what it might be?
I will be most interested in any explanations you may have. Seriously.
PIPPEN I agree 100%. Evidence is so very clear,look at the Mt. Pinatubo eruption(very recent evidence) and what temperatures did for a short time following that eruption.Look at the graph Dr. Spencer has, which clearly illustrates this fact. Google Dr. Spencer to go to this web-site.
Yes the effects are short lived but they are real and again each and every volcanic eruption is different, and goes off under different climatic scenarios..
There are HUNDREDS of studies that run counter to what Willis has concluded.
I would like to ask Willis Eschenbach a direct question.
Have you formed the auto-correlationfunction of your model? If so, does it conform to the calculated ACF from the data? I think you may find determination of the latter quite difficult and not immediately accessible in “R”. I would be extremely careful about applying a filter if I were you as this can give rise to wildely incorrect results in calculating correlation functions.
You will find that that your model does not does not conform to the correlation structure of the temperature signal – this is well known.
In this case your model is wrong, either because the structure of the system is linear but more complex than the single thermal capacitance you assume, or it is a non-linear process with possibly, as has been speculated, Hurst process dynamics.
I would be interested to know how you resolve this problem.
” ALL-CLEAR IN THE STRATOSPHERE”
http://spaceweather.com/archive.php?view=1&day=19&month=12&year=2010
Earth’s stratosphere is as clear as it’s been in more than 50 years. University of Colorado climate scientist Richard Keen knows this because he’s been watching lunar eclipses. “Since 1996, lunar eclipses have been bright, which means the stratosphere is relatively clear of volcanic aerosols. This is the longest period with a clear stratosphere since before 1960.”
“The lunar eclipse record indicates a clear stratosphere over the past decade, and that this has contributed about 0.2 degrees to recent warming.”
I wonder about the IR blocking effects of a major equatorial volcanic eruption with enough ash thrown into the upper atmospheric layers to prevent rain-out AND that occurs in equatorial regions.
What would be the effects during El Nino, neutral, and La Nina events if all this ash was in the upper atmosphere circling the equatorial belt? Recharging events (neutral to La Nina) serve to keep our oceans warm, thus keeping US warm when El Nino’s cough up heat onto land. What if ash prevented that recharge from occurring to the degree it would normally occur under clear sky conditions?
Given the above, I am wondering if explosive power, timing and location are important factors in whether or not volcanic eruptions can have long term affects that go beyond the rain-out period immediately following explosions.
“…are important factors…”
[Fixed. -w.]
Steven Mosher September 22, 2013 at 4:19 pm
[..] sadly you cant calculate sensitivity […] (from)…
Which bit of THERE IS NO SUCH THING AS SOME Y=(F)x ‘climate sensitivity’ calculation are you not following?
Reading through the thread we have everything from ‘my new climate model suggests’, ‘the price of Wheat would indicate’ and ‘the year without a Summer’ (Scotland only?) all held up as evidence that Willis is wrong. All of it it BS.
Simple – tending toward a ‘Snowball Earth’ – his ‘mechanism’ can’t help. No clouds/thunderstorms ever form and so that control mechanism has reached its lower limit.
Working the other way (eg Solar output increases noticeably) the ’emergent thermostatic phenomena’ can spread north and south and increase in intensity and I have no idea where the upper limit lies, many thousands of W/m2, I suspect.
Bottom line (for those worried about ‘anomalies’) – grab a base temp (15C or whatever you chose) and superimpose those anomalies. Tell me then just how much you would expect to be paid for designing a Planet and a control system that, with no unexpected changes, could hold surface temps to +/- tenths of a degree over significant periods. I would be a very rich man.
Something also occurred regarding ‘Sun reflecting particles high up in the atmosphere’ – more (badly named) ‘greenhouse effect’ – once reflected from the surface – does that ‘layer’ not also prevent ‘visible light’ from leaving? 15um or 500nm shouldn’t they both bounce back and forth increasing their time at the surface with suitable interference?
Anyway Willis … welcome back. Hope you enjoyed our historical landmass.
Having read some of the responses to this post – bet you wish you could have extended your holiday though. Some people just don’t read. You are just too polite sometimes
Willis: “Since I’ve been a heretic for a decade or so, your attempt to be all pally by welcoming me on board is an insult … likely unintended, but that just makes it worse.”
Willis, easy, I sure didn’t mean that derogatory, yes, unintended, didn’t realize you held such a viewpoint of yourself for so long, thought you were making a movement to total disbelief. That’s all. If it’s been a decade, fine.
I, as others, do greatly appreciate your work and insight into these areas though I hope you have the flexibility to possibly be incorrect in a few of your viewpoints where we do differ, one of those being that you do not feel the mass of atmospheres matter at all, I do. Keep an open mind, stay a real scientist. I’ll always give you that same courtesy. Even here on this post.
Now after reading the post and comments, give a close look at what Frank commented, his stood out, it adds a thick layer of support for what you have found on volcanoes even though I think his comment of 1.4°C sensitivity is not correct. He is correct on the problem of using power instead of energy, mass, and time. Hope you give me the leeway to disagree with you every now and then without you always taking such offense.
What manner of observational methods, data collection methods, experimental methods, and analytical methods would be necessary either to demonstrate or to disprove Willis’ theory that the earth’s climate system operates mostly as a self-regulating, self-stabilizing heat engine?
Greg and Geran: Thanks for the replies to my comment. I usually feel like most readers will cheer anything opposing the consensus (no matter how flawed) and will ignore or jeer anyone that criticizes. Unfortunately, in this case Willis is trying the do the equivalent of understanding the relationship between acceleration and velocity by looking for a correlation between the two. The two phenomena are related (by integration or differentiation), but correlation isn’t the right method for understanding their relationship. One must integrate power over time and take heat capacity into account, before you can understand how much temperature change a forcing should produce. And since radiative forcing represents change in the power flux entering or leaving the earth, Willis is likely to remain confused as long as he continues to reject this concept. Recognizing the relevance of radiative forcing to temperature change doesn’t mean that temperature change can’t be suppressed by negative cloud feedback (or amplified by positive water vapor feedback). Accepting the concept of radiative forcing doesn’t mean one must believe in high climate sensitivity. Observations are most consistent with an ECS around 1.5 degC. (High climate sensitivity comes from climate models – which rely on 1-2 dozen parameters whose precise values aren’t known (in addition to physics). Change those parameters and you change climate sensitivity.
If you want to know more about Pinatubo, see the discussion at the Blackboard. It’s excellent. http://rankexploits.com/musings/2012/pinatubo-climate-sensitivity-and-two-dogs-that-didnt-bark-in-the-night/