Volcanoes Once Again, Again

Guest Post by Willis Eschenbach [also, see update at the end of the post]

Anthony recently highlighted a couple of new papers claiming to explain the current plateau in global warming. This time, it’s volcanoes, but the claim this time is that it’s not the big volcanoes. It’s the small volcanoes. The studies both seem to follow what I call “Willis’s Rule of Author Count”. The first study is Total volcanic stratospheric aerosol optical depths and implications for global climate change, by D. A. Ridley, S. Solomon, J. E. Barnes, V. D. Burlakov, T. Deshler, S. I. Dolgii, A. B. Herber, T. Nagai, R. R. Neely III, A. V. Nevzorov, C. Ritter, T. Sakai, B. D. Santer, M. Sato, A. Schmidt, O. Uchino andJ. P. Vernier. The second study is Observed multi-variable signals of late 20th and early 21st century volcanic activity, by Benjamin D. Santer, Susan Solomon, Céline Bonfils, Mark D. Zelinka, Jeffrey F. Painter, Francisco Beltran, John C. Fyfe, Gardar Johannesson, Carl Mears, David A. Ridley, Jean-Paul Vernier, Frank J. Wentz.

Now, Willis’s Rule of Author Count says that the quality of any study is inversely proportional to the square of the number of listed authors. And these two studies have seventeen and twelve authors respectively … not a good sign.

The abstract of the first paper says:

Understanding the cooling effect of recent volcanoes is of particular interest in the context of the post-2000 slowing of the rate of global warming. Satellite observations of aerosol optical depth above 15 km have demonstrated that small-magnitude volcanic eruptions substantially perturb incoming solar radiation. Here we use lidar, Aerosol Robotic Network, and balloon-borne observations to provide evidence that currently available satellite databases neglect substantial amounts of volcanic aerosol between the tropopause and 15 km at middle to high latitudes and therefore underestimate total radiative forcing resulting from the recent eruptions.

The abstract of the second paper, in turn, says:

The relatively muted warming of the surface and lower troposphere since 1998 has attracted considerable attention. One contributory factor to this “warming hiatus” is an increase in volcanically-induced cooling over the early 21st century. Here, we identify the signals of late 20th and early 21st century volcanic activity in multiple observed climate variables. Volcanic signals are statistically discernible in spatial averages of tropical and near-global SST, tropospheric temperature, net clear-sky short-wave radiation, and atmospheric water vapor.

Now, it is certainly possible that “small-magnitude volcanic eruptions substantially perturb incoming solar radiation”. There are lots of things that perturb incoming solar radiation, with clouds heading the list. Whether small volcano emissions in turn perturb the global surface temperature is a separate question.

But for eruptions to be an explanation for the current plateau in global warming, the authors would have to show a significant increase in volcanic eruptions in the 21st century. And unfortunately (but predictably) I see no sign in either paper that they have even tried to do that.

So let’s do their job for them by taking a look at the actual records of eruptions, both large and small. The data on all known eruptions is available from the Smithsonian Volcanism Project.

Now, we have some choices in how to display this data. Let me show three of these different ways.

First, we can show the total numbers of eruptions by year, without regard to the size of the eruption. Figure 1 shows that information:

Figure 1. Count of all volcanic eruptions, regardless of their strength, during the end of the 20th and the start of the 21st centuries.

As you can see, there is very little difference between the post-2000 (or post 1998, depending on the study) eruption count and the number of eruptions during the end of the 20th century. After 2000 (or 1998), it went up a bit, then it went down a bit … overall, little change.

But wait, I can hear you saying, the eruptions are not all of the same strength … what is the average strength of the eruptions? And reasonably so, since strong eruptions would have a bigger effect than small eruptions. So let’s look at that data.

The strength of an eruption is measured by the volcanic explosivity index, or VEI. This is a logarithmic scale. This means that an eruption with a VEI of 5 is ten times stronger than an eruption with a VEI of 4, and so on.

In order to properly average these, it’s necessary to use a “logarithmic mean” To do this, you first convert the VEIs to actual values (by taking ten to the power of the VEI). Then you average the actual values, and then take the logarithm of the resulting average to convert it back into the logarithmic VEI scale. Figure 2 shows that result:

Figure 2. Annual logarithmic mean of the volcanic explosivity index, all volcanoes.

In 1991, there were two strong eruptions, Pinatubo (VEI of 6) and Cerro Hudson (VEI of 5). Other than that, there’s not a lot of variation.

Once again, you can see that the post 2000 (or post 1998) average strength of the volcanic eruptions are little different from the strength of the eruptions prior to the turn of the century. So that cannot be the cause of 21st century plateau in global surface temperatures.

Finally, we could read the implicit claim as being that there is some kind of increase in the number of small volcanic eruptions. After all, the authors say that these are the overlooked eruptions. So let’s take a look at the small pre- and post-2000 eruptions.

Figure 3. Annual count of the smaller eruptions, those with a volcanic explosivity index of less than 3.

Once again, we see little change in the number of small volcanoes. After 2000, it goes above the average, and then it goes about the same amount below the average.

Conclusions? Well, the papers may be correct in their claim that the effect of eruptions on the clarity of the atmosphere may have been underestimated.

But they are absolutely not correct in the claim that this underestimation reveals the cause of the recent 18+ year plateau in temperatures as being eruptions. There is almost no post-2000 change in either the number of eruptions, the strength of eruptions, or the number of small eruptions.

Overall? I’d say that Willis’s Rule of Author Count, that the quality of any study goes down inversely proportional to the square of the number of listed authors, is validated once again …

[UPDATE: The underlying claim of these two papers is that although there have been no large eruptions in the 21st century, it is the weaker eruptions that are causing the plateau in temperature. These are eruptions with a volcanic explosivity index (VEI) of four. Some commenters below still think that the eruptions of VEI four are significant. The Santer document shows the effect of some of the VEI 4 eruptions on the stratospheric aerosol optical depth (SAOD), which is their main indication of volcanic change. The study says:

We use stratospheric aerosol optical depth (SAOD) data from Vernier et al. [2011] to study changes in stratospheric loadings of volcanic aerosol.

The eruptions  make a change of about .002 in the SAOD, viz:

Now, that looks kind of impressive … until you compare it to the larger volcanoes (source):

You can see the sizes of Krakatoa in the 1880s, Pinatubo in 1991, El Chichon in 1982, and Mt. Agung in 1963, along with some smaller volcanoes … and then you can see the part that Santer et al. are discussing. This is the almost-flat line in the post-2000 era. Sorry, but given the short-term, weak, local effects of even the largest volcanoes, I’m not buying the idea that those tiny post-2000 wiggles have any discernible effect at all.

My best regards to you all,

w.

ONCE AGAIN: If you disagree with someone, please do everyone the favor of QUOTING THE EXACT WORDS THAT YOU DISAGREE WITH. This prevents all kinds of misunderstandings and misrepresentations.

FURTHER READING: I note that this is not the first time that Susan Solomon has made the claim that volcanoes are the cause of the current pause in temperatures. In addition, she was the main mover behind one of the IPCC reports, from memory the Fourth, and is fully and completely invested in the meme of “CO2 Roolz Everything, OK” … whenever I see her name on a study, I’m sad to report that I just wince. See here for my discussion of her previous work.

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Curt

My understanding is that conventional wisdom says that “small” volcanic eruptions have less than proportional effect because their ejections don’t get that high in the atmosphere and are quickly rained out. Is this being challenged?

Dunno, but carbonyl sulfide (COS) could be a way for the less energetic eruptions to have a way of getting sulfur to the stratosphere. COS is not very reactive in the troposphere, but if it gets hit with short wavelength UV, it dissociates and can become part of the sulfate formation mechanism. UV that short of a wavelength is only plentiful in the stratosphere. The big caveat is going to be how quickly or efficiently, COS can diffuse across the tropopause. From what I understand, COS tends to stay in the troposphere for up to nine years.

Bill Illis

We can barely find a temperature signal from the very largest stratospheric eruptions. Willis has posted on this several times.
The large ones do clearly show up in the lower stratosphere temperatures but for the surface, it is only the largest ones that go high into the stratosphere that seem to have a (barely detectable) signal. Some of the largest ones leave nothing in the temperature series.
If we can only barely detect the largest ones, how can several small ones that leave no stratospheric or aerosol optical depth signal, have an impact.

beng1

Right. The graph of optical transmission plainly shows significant but brief excursions from large volcanoes, then a quick return to a remarkably smooth & consistent plateau (while “little” volcanoes are constantly occurring). That graph says all we need to know.
More warmy attempts to explain the lack of predicted CO2 warming — just like exaggerated human-aerosol effects.

First of all, I am not a “warmy” I think the whole idea of Globular Warming is a giant festering crock of [insert disgusting material here].
I do, however, think that the background level of the Junge layer is affected by this mechanism, but the guys that track the Tau line seem to have given up interest since about 2012. I was thinking that maybe a signal from the Tolbachik flood basalt or the Holurhaun eruption in Iceland may show some effect. I guess it’s sort of my fault for expecting Nasa to keep a data set updated.
http://data.giss.nasa.gov/modelforce/strataer/
An oddity though… Mobile Bay actually started forming Ice recently. Not a lot of ice, mostly a “hey, check that out” sort of thing for the locals. Not totally uncommon, but it is quite rare.
http://fox10tv.com/2015/01/08/mobile-bay-spectacular-as-frozen-wonderland/

Please see this Aerosol Optical Depth Animation from January 2005 to November 2014 – press the Play button
http://earthobservatory.nasa.gov/GlobalMaps/view.php?d1=MODAL2_M_AER_OD
Can anyone spot any volcanoes? I cannot.
You can clearly see the significant effects of agricultural burning in South and Central America and Africa, and Southeast Asia.
Here is the commentary that accompanies the Aerosol animation:
High aerosol amounts are linked to different process in different places and times of year. High aerosol amounts occur over South America from July through September. This pattern is due to land clearing and agricultural fires that are widespread across the Amazon Basin and Cerrado regions during the dry season. Aerosols have a similar seasonal pattern in Central America (March-May), central and southern Africa (June-September, and Southeast Asia (January-April).
In other cases, however, aerosol concentrations are not related to fires. For example, from May through August each year, aerosol amounts rise dramatically around the Arabian Peninsula and nearby oceans due to dust storms. Elevated aerosol amounts nestle at the foothills of the Himalaya Mountains in northern India in some months, and linger over eastern China for much of the year. These elevated aerosol amounts are due to human-produced air pollution.
_____________
Please see this Fires Animation from March 2000 to November 2014 – press the Play button
http://earthobservatory.nasa.gov/GlobalMaps/view.php?d1=MOD14A1_M_FIRE
Here is the commentary that accompanies the Fires animation:
The fire maps show the locations of actively burning fires around the world on a monthly basis, based on observations from the Moderate Resolution Imaging Spectroradiometer (MODIS) on NASA’s Terra satellite. The colors are based on a count of the number (not size) of fires observed within a 1,000-square-kilometer area. White pixels show the high end of the count —as many as 100 fires in a 1,000-square-kilometer area per day. Yellow pixels show as many as 10 fires, orange shows as many as 5 fires, and red areas as few as 1 fire per day.
Some of the global patterns that appear in the fire maps over time are the result of natural cycles of rainfall, dryness, and lightning. For example, naturally occurring fires are common in the boreal forests of Canada in the summer. In other parts of the world, the patterns are the result of human activity. For example, the intense burning in the heart of South America from August-October is a result of human-triggered fires, both intentional and accidental, in the Amazon Rainforest and the Cerrado (a grassland/savanna ecosystem) to the south. Across Africa, a band of widespread agricultural burning sweeps north to south over the continent as the dry season progresses each year. Agricultural burning occurs in late winter and early spring each year across Southeast Asia.
_______________
Please see this Carbon Monoxide Animation from March 2000 to November 2014 – press the Play button
http://earthobservatory.nasa.gov/GlobalMaps/view.php?d1=MOP_CO_M
Here is the commentary that accompanies the Carbon Monoxide animation:
These maps show monthly averages of global concentrations of tropospheric carbon monoxide at an altitude of about 12,000 feet. The data were collected by the MOPITT (Measurements Of Pollution In The Troposphere) sensor on NASA’s Terra satellite. Concentrations of carbon monoxide are expressed in parts per billion by volume (ppbv). A concentration of 1 ppbv means that for every billion molecules of gas in the measured volume, one of them is a carbon monoxide molecule. Yellow areas have little or no carbon monoxide, while progressively higher concentrations are shown in orange and red. Places where the sensor didn’t collect data, perhaps due to clouds, are gray.
In different parts of the world and in different seasons, the amounts and sources of atmospheric carbon monoxide change. In Africa, for example, the seasonal shifts in carbon monoxide are tied to the widespread agricultural burning that shifts north and south of the equator with the seasons. Fires are an important source of carbon monoxide pollution in other regions of the Southern Hemisphere, such as the Amazon and Southeast Asia.
In the United States, Europe, and eastern China, on the other hand, the highest carbon monoxide concentrations occur around urban areas as a result of vehicle and industrial emissions. Fires burning over large areas in North America and Russia in some years can be an important source. The MOPITT observations often show that pollution emitted on one continent can travel across oceans to have a big impact on air quality on other continents.
________________
What about CO2? There is not similar CO2 animation from this NASA site, but here is a CO2 animation from September 2002 to July 2008 (give it a minute to load):
http://svs.gsfc.nasa.gov/vis/a000000/a003500/a003562/carbonDioxideSequence2002_2008_at15fps.mp4
Try to find the impact of fossil fuel combustion in this CO2 data – I cannot.
No sign of volcanoes either…

Maybe they refer to volcanoes hidden in the oceans or in their imagination? International socialism need the predictive power of progressive enlightenment liberalism(policy based science/propaganda) to get a climate treaty in Paris later this year?

Some of the people behind these 2 studies are the same. Why do they participate in 2 different studies to tell the same story? Maybe if the same people tell the same story in 2 different studies then the 2 studies verify each other?

Climate change| that is real and that you can measure.
The ghost of climate change: climate change that is imaginary and needed to promote policy.
The trinity of climate change: the result of climate science being politicized.

It’s just policy enlightened science?

motogeek

*sigh* Most of the warmista’s won’t even admit there is a pause *at all* when you try to discuss the pause with them. I do see that articles like this have their place (getting them to admit there is a pause at all). How much can people have their heads shoved up their asses?

latecommer2014

Why do we even consider these frauds. They are political scientist working at the bid of their controllers and contemptible

jorgekafkazar

Proctocraniosis is epidemic among climate charlatans.

jimmyy

Joe Crawford

A.K.A. in situ proctology.

Robert of Ottawa

They don’t have their heads up their “asses”, or horses for that matter.
They do have their hands in the till, though.

scf

They know they can adjust the data to make the pause disappear, they just have to wait a few years. In fact you can already see the front end of the pause changing in some data sets.

Gentle Tramp

At least Thomas Stocker, a leading head of the IPCC, admits the pause by declaring it is finished now by the “heat record” of 2014. See here:
http://www.schweizamsonntag.ch/ressort/meinung/kann_die_menschheit_die_erderwaermung_stoppen/
It’s a rather unscientific conclusion of course, but Stocker is more an activist than a true scientist, according to this very fitting quote by Matt Ridley about the “heat record” of 2014:
“True scientists would have said: this year is unlikely to be significantly warmer than 2010 or 2005” and left it at that.

But wait! These two papers were peer reviewed, were they not. You must have overlooked something, Willis. Peer review is sacrosanct.

noaaprogrammer

If they get 97% of all scientists to contribute to the article, then peer review is a shoo-in.

James Strom

Good point. I was about to object to Willis’ rule, but, as you suggest, more authors-more friends, and more peer friends.

george e. smith

I believe that every peer reviewed paper that purports to have more than one author, should specifically disclose exactly what part of the paper was written by which author.
I know for example, that in the US Patent Office peer reviewed literature (AKA US patents), Every named “inventor” must be able to claim SOLE responsibility for at least ONE element of at least ONE claim in the patent, that eventually gets by the examiner to become a part of the claimed invention. I have never been a “co-inventor” of any element of any patent claim, but I have added my share of novel features to gizmos, that also included individual contributions from other inventors.
I have never stumbled across their ideas at the same time, nor have they mine.
But collectively we have improved on each others work.
But of course this is the age when 4 yr. olds are taught in kiddiegarden, and subsequently, to sit quietly at a table with a bunch of other restless brats, and let the smart kid solve the problem, then all get the same grade. This eventually becomes a focus group.
Just how many “scientists” have their names on the paper that discovered the Higgs boson, or whatever it really is that they think they have found ??
It often works in reverse; for example, when Steven Chu gets the Nobel Physics prize for inventing “optical tweezers”, but the Swedes ignore the Bell Labs chap who really invented them, and then hired, and taught Chu, how to do it many years later.
And of course in 2014, they ignored Dr. Nick Holonyak who invented the visible (red) LED, but gave the Nobel Physics prize to Shuji Nakamura, who of course invented the blue LED.
Nakamura was an admirable and deserving choice for the prize, but they should have included Holonyak, who started the whole thing rolling, decades earlier.
I think the real authors of scientific advances should be recognized by name, not by the focus group they were in.

Boulder Skeptic

First disclaimer: I have not yet opted to pay to view the full articles for these two papers.
Second disclaimer: regarding authors showing a significant increase in their chosen volcanic eruptions in the 21st century, I am going to assume to be correct Mr Eschenbach’s assertion that “unfortunately (but predictably) I see no sign in either paper that they have even tried to do that.”
I also would expect to read somewhere in each of these papers that the volcanic activity being claimed as the mechanism for reduced 21st century global warming would be clearly shown to be statistically or significantly increased as compared to periods of previous higher warming rates. As a result, I have a couple of open questions for any of the more vocal AGW proponents that regularly post here (e.g. Mr Stokes, Mr Mosher, Mr Socrates, Mr Gates, etc.)
First question: Can we agree that if this major oversight/omission of the subject articles identified and separately analyzed by W.Eschenbach does exist, that the peer review process at Geophysical Research Letters is flawed?
Second question (possibly N/A depending on answer #1): If you do not agree that the GRL peer review is flawed, can you explain why the omission as identified by W. Eschenbach would be acceptable for the conclusion drawn?
Bruce

Jimbo

It would be interesting if we knew about small volcanic activity between 1910 to 1950. We had a warming then cooling trend.
http://www.metoffice.gov.uk/media/image/j/l/warmingtrend.gif

Abstract
…..Preliminary application of the eruption chronology to global and hemispheric temperature trends for the period 1880–1969 demonstrates that episodes of frequent and intense ash-producing eruptions tend to be associated with periods of cooler hemispheric temperatures, while volcanically quiescent episodes tend to correspond with periods of hemispheric warming.
http://www.sciencedirect.com/science/article/pii/003101827990083X

They, Santer, Salomon and Ridley from the first study first per viwed the other study. Then Santer, Solomon and Ridley from the other study per viewed the first study?

bones

Willis, Excellent. Thanks for your effort. My gut feeling was that the studies were nonsense, but your finding and analyzing the relevant data took all of the guesswork right out of it. Thanks, much appreciated!

clipe

Small volcanoes? Sounds like Napoleon Complex to me.

Rick K

I love your succint clarity, Willis!

Streetcred

+1

Mike the Morlock

Willis and others please do look at the dates of acceptance for the second article also the first. X-mas eve for the second? thats peer review?
michael

Mike the Morlock

oops 29th not 24th of dec but then isn’t this vacation time? Why would people be be rushing out a paper it this time of year?

Willis,
At this point, when the overwhelmingly majority of authors on papers, such as these, are little more than rubber stamps of consensus “communication”, one wonders if some of these people are “authors” of mutually contradicting papers. With 50 plus reasons and counting as well as pause denial, some of these authors are likely to truly be typing out of both sides of their keyboard.

ossqss

The logarithmic nature of CO2 and temperature is driving them nuts! What is the saturation point of CO2 for IR anyhow?

It doesn’t saturate because optical depth increases unconstrained. But the log function therein implied means more causes less. Guy Callendar showed this in 1938.

MODTRAN, doesn’t tell you saturation point but it does tell you the degree of transmittance. If you what you can pug-in what-if scenarios and work it out.

JimS

Good job, Willis. You brought out the obvious, and as I sometimes say, the best way to refute the climate change extremists is through actual data. They seem allergic to it. Actual data drives them to their models to receive comfort.

CTM:
“… truly be typing out of both sides of their keyboard.”
Thank you for a very amusing mental image regarding the two-faced CAGW climateer profiteers using their keyboards in perverse ways… :->

Is there a factor for authors common to multiple papers?

Don Horne

Yes. It’s the cube of the sum total of the authors. IOW, the more the merrier…!

Anything is possible

“Now, Willis’s Rule of Author Count says that the quality of any study is inversely proportional to the square of the number of listed authors. And these two studies have seventeen and twelve authors respectively … not a good sign.”
=======================================
Excellent rule Willis, which deserves a suitable name.
May I suggest “Widdecombe Fair Science”

AlexB

In such cases the author list should be shortened to Uncle Tom Cobbley et al.

Willis’s Rule of Author Count has an immediate, intuitive, appeal. I would like to see it backed up by something more than intuition, and gain at least the status of Parkinson’s Law and the Peter Principle.

Anything is possible,
Yikes! Fingernails on a blackboard! Glad I don’t have to live with that.

Mac the Knife

Now Showing: The Little Volcano That Could!
Sound Track by Ben Santer: I think I can….I think I can….I think I can…..

According to the review I saw, the show blows.

If I understand correctly, volcanoes produce cooling effects via aerosols and the effects of aerosols were taken into account by NASA authors and their colleagues when they estimated +0.6 W/m2 as the recent net global warming.
James Hansen et al. (2011) Earth’s energy imbalance and implications, Atmos. Chem. Phys., 11, 13421-13449, 2011). URL:
http://www.atmos-chem-phys.net/11/13421/2011/acp-11-13421-2011.pdf
Based on the result obtained by Hansen et al., Graeme Stevens had this to say:
The net energy balance is the sum of individual fluxes. The current uncertainty in this net surface energy balance is large, and amounts to approximately 17 Wm–2. This uncertainty is an order of magnitude larger than the changes to the net surface fluxes associated with increasing greenhouse gases in the atmosphere (Fig. 2b). The uncertainty is also approximately an order of magnitude larger than the current estimates of the net surface energy imbalance of 0.6 ±0.4 Wm–2 inferred from the rise in OHC. The uncertainty in the TOA net energy fluxes, although smaller, is also much larger than the imbalance inferred from OHC.
Graeme L. Stephens et al, An update on Earth’s energy balance in light of the latest global observations. Nature Geoscience Vol. 5 October 2012
URL: http://www.aos.wisc.edu/~tristan/publications/2012_EBupdate_stephens_ngeo1580.pdf
The estimate of 0.6 Wm-2 was updated by Loeb and others in 2012 to 0.5 Wm-2.
Reference: Norman G. Loeb, John M. Lyman, Gregory C. Johnson, Richard P. Allan, David R. Doelling,Takmeng Wong, Brian J. Soden and Graeme L. Stephens. Observed changes in top-of-the-atmosphere radiation and upper-ocean heating consistent within uncertainty. (Nature Geoscience Vol 5 February 2012)
This revised estimate leads to the conclusion that the energy imbalance is 0.15% of incoming solar radiation. Since the uncertainty is in both downward and upward flux, the energy imbalance is 0.075% of total energy flux. This estimate of energy imbalance is so small that little confidence can be placed on its accuracy. We ought to regard the current estimate of global warming as arising from spurious precision.
The metric for net warming is +0.5Wm-2 compared with 17Wm-2 uncertainty. The uncertainty is 34 times as big as the measured net warming.
What the authors of these two volcano papers purport to do is to show that the net energy imbalance would be higher than +0.5Wm-2 if small-scale vulcanism were taken into account. However, adjusting a metric that is spuriously precise would get us nowhere at all. Even if they double the net warming to +1.0 Wm-2, the uncertainty would still be 17 times bigger than the measured warming.

SkepticGoneWild

Frederick,
Fantastic post, Frederick. If you look further in Hansen’s paper, it gets worse:
“We also must quantify the causes of changes of Earth’s energy imbalance. The two dominant causes are changes of greenhouse gases, which are measured very precisely, and changes of atmospheric aerosols. It is remarkable and untenable that the second largest forcing that drives global climate
change remains unmeasured. We refer to the direct and indirect effects of human-made aerosols”

I see nowhere where they measure volcanic aerosols.
Now as to this alleged energy imbalance caused by humans, Hansen makes some startling observations:
“The precision achieved by the most advanced generation of radiation budget satellites is indicated by the planetary energy imbalance measured by the ongoing CERES (Clouds and the Earth’s Radiant Energy System) instrument (Loeb et al., 2009), which finds a measured 5-yr-mean imbalance of 6.5 W m−2 (Loeb et al., 2009). Because this result is implausible, instrumentation calibration factors were introduced to reduce the imbalance to the imbalance suggested by climate models, 0.85 W m-2″</b
So they introduce a phony calibration factor because the measurement error is something like 600%. Bottom line, the alleged energy imbalance cannot even be measured by satellites. The other method of measuring energy imbalance is indirectly through "measurements of changes in the heat content of the ocean and the smaller heat reservoirs on Earth" (per Hansen) Call me completely skeptical if this method can measure to the accuracy of 0.5 W/m-2.. Hansen had this to say about the ocean heat content approach:
"An alternative potentially accurate approach to measure Earth’s energy imbalance is via changes in the ocean heat content, as has been argued for decades (Hansen et al.1997) and as is now feasible with Argo data (Roemmich and Gilson, 2009; Von Schuckmann and Le Traon, 2011). This approach also has sampling and instrument calibration problems, but it has a fundamental advantage: it is based on absolute
measurements of ocean temperature. As a result, the accuracy improves as the record length increases, and it is the average energy imbalance over years and decades that is of greatest interest.”

“Potentially accurate”?? So further bottom line. The ALLEGED energy imbalance simply CANNOT even be measured. When one has a hypothesis, the scientific method requires confirmation by testing. If the testing, or measurement cannot be performed, the hypothesis remains unconfirmed. QED.

Because this result is implausible, instrumentation calibration factors were introduced to reduce the imbalance to the imbalance suggested by climate models, 0.85 W m-2

Holy donuts Batman! What is the purpose of putting a satellite into orbit if you are simply going to adjust it to give the answer you already expected to see? Oh look, the books don’t balance. Lets just adjust the figures so they do. In business that is called go to jail. In climate science it is called business as usual. Standard Operating Procedure.
If observations don’t match the models, adjust the observations.

Joe Crawford

But…but… we were told the models were tuned to match the data. Now they’re tuning the data to the models? Just

Wow!

Barry Cullen

Exactly!

SkepticGoneWild

ferdberple stated:
” What is the purpose of putting a satellite into orbit if you are simply going to adjust it to give the answer you already expected to see?
Exactly. This is how they do science. It’s pure insanity. Their whole AGW hypothesis is a ruse. The alleged energy imbalance can’t even be scientifically measured, so they fake the measurements by adjusting the data to comply with what was expected.

Pretty clear to me there is an inverse correlation between the number of authors and volcanic activity…/

Nivlek

Excellent critique. The effluvium (love that word – describes the content of the paper well, don’t you think?) from small volcanoes clears from the atmosphere quickly because it doesn’t reach so high and there isn’t much of it. And, of course, it rains. The dust from big volcanoes can be seen at sunset/sunrise for up to 3 years, so even this is not enough to explain a 19 year hiatus. I was near Volcan Hudson when it went off – an immense amount of material was introduced into the atmosphere, but the skies cleared quickly. Incidentally, much of the effluvium was large particulate pumice – it had near zero residence time in the atmosphere.
Can I help them out in their salary aspirations by suggesting grants may be awarded for studies on increased dust concentration in the atmosphere from drying deserts? Particulate pollution from nano- plastic particles and nano-technology by-products? Anti-matter coronal effects from the top of thunderstorms? Increased eructation from processed foods. What ever takes take their fancy – they don’t seem shy of suggesting all sorts of mechanisms – other than water vapour/ice which really is important and which could easily provide the negative feedback loop that is holding the temperature constant in spite of increasing CO2 levels.

Jeff L

Beautiful data Willis – I love it when alarmist arguments can be quickly dismissed with a little basic research & data. Exposes them for the political agenda driven bunch they are versus the science driven bunch skeptics are.
Well done!

u.k.(us)

Ok, it took awhile but I’ll now have to agree, grudgingly, that volcanoes ain’t got much pull.
Which only gives more weight to the other drivers.

jorgekafkazar

Except they’re a major source of CO2.

Unmentionable

And excepting that volcanism is by far mostly submarine, and eruptions are punctuated (and still possibly cyclic) and exhale a great deal of heat into ocean basins, which will modify currents. So volcanism is far from sidelined, it is very much a player in that regard, and also in regard to known optical effects of big eruptions.
It’s CO2 rise that’s better and better explained by volcanism, and that what’s being sidelined here, not volcanoes, when ocean cyclicity is deeply implicated in climate variability, and altered by bottom water thermal regime (which is the open question).

Unmentionable,
The same problem of CO2 from volcanoes as for aerosols: if they are responsible for the increase over the past 160 years, there should be an enormous increase in activity (a 4-5 fold since 1959, when accurate measurements started), which isn’t seen anywhere.
Further most CO2 from undersea volcanoes is absorbed in the deep oceans and distributed in the enormous amount of (bi)carbonates there.
Last but not least, volcanic CO2 has a higher δ13C level than CO2 in the atmosphere. The atmosphere and the ocean surface shows a sharp decline in δ13C level, completely in parallel with human emissions…

Unmentionable

Ferdinand Engelbeen
January 10, 2015 at 3:39 am
“Last but not least, volcanic CO2 has a higher δ13C level than CO2 in the atmosphere. ”

Yes, it looks unlikely (I regretted the sentence the moment I posted). As with all oceanic data sample coverage is low or very low and data surprisingly diverse with geography, and with deposition context. But a small δ13C depletion is the overall. So it’s an overstatement to say rising atmospheric CO2 is adequately explained by underwater volcanism that simultaneously imparts a thermal rise, inducing any actual warming cycle.

Bruce Cobb

Which ones? Natural or fantasy?

“But for eruptions to be an explanation for the current plateau in global warming, the authors would have to show a significant increase in volcanic eruptions in the 21st century. ”
No. they would not have to show this.
Showing it would help, but its not necessary.
What’s important is total forcing.

jorgekafkazar

Except that CO2, the putative major forcing has risen during this period at about the same rate as before it. For the temperature to flatline, there must have been a drop in total forcing–something else must have changed. If not rising volcanic SO2, what?

Willis Eschenbach

Steven Mosher January 9, 2015 at 9:16 pm

“But for eruptions to be an explanation for the current plateau in global warming, the authors would have to show a significant increase in volcanic eruptions in the 21st century. ”

No. they would not have to show this.
Showing it would help, but its not necessary.
What’s important is total forcing.

Say what? Given that as I have shown, there is no difference in the volcanic eruptions during the time of increasing temperatures and the time of the plateau in warming, then how on earth can the eruptions be the reason for the pause?
You’ll have to explain that claim a whole lot better than you’ve done so far, Mosh.
w.

I think Mosh must be thinking that it is the total force of the accumulated Volcanic Emissions over the last 2 Centuries has reached the Tipping Point at the end of 1997. Obviously you proved that there was no change in average volcanic activity, however they may wish to measure it.

Michael Whittemore

Every volcanic eruption is chemically different. How many or how intense these eruptions are means nothing. Aerosol forcing has been measured by the paper “Total volcanic stratospheric aerosol optical depths and implications for global climate change” which states “we determine the global volcanic aerosol forcing since 2000 to be −0.19 ± 0.09 Wm−2 [which] translates into an estimated global cooling of 0.05 to 0.12°C.”

Joe Civis

mosh is correct… with “climate science” the formula is come to desired conclusion, “adjust” data to fit conclusion…. deny any contrary indicators… make wild guesses with lots of maybe and possibly… and publish, publish, publish! It does not matter if right or wrong just publish what supports the predetermined desired conclusion, ignore all else and call lots of unsavory names those that disagree…. “climate science” at its best. not sure where to put the “sarc” tag but there might need to be one somewhere…
Cheers!
Joe

Mac the Knife

In total, it is the analyses being forced, as are the dubious data ‘adjustments’.
Unaffected, the climate continues to change, ‘pause’, and cycle, naturally.
The null hypothesis stands….and that’s what’s important.

TerryS

What they would have to show is that the volcanic aerosols have increased and they have not shown this.
What they have shown is that there is more, between 15k and the tropopause, than they originally thought. They then use this and the “pause” to infer that there was less earlier in the 20th century and then blame the pause on this.
They have no data, from AERONET, pre 98 with which they can determine the aerosol levels.

Joe Crawford

Another beautiful example of the logic of ‘Climate Science’. ‘Y’ is happening now, since everyone knows ‘X’ causes ‘Y’, then ‘X’ must have been the case in the past… Which proves ‘Y’ = k’X’.

mpainter

Steven Mosher: ” What’s important is total forcing”
####
Actually no , Steven. What’s important is the _change_ in total forcing. There seems to have been no attempt to demonstrate such a change from the period previous to the study.
That is the reason for comparing volcanic activity, Steven.
Without showing that the study era (post 2000) was an era of increased volcanic aerosols, then their conclusion is simply a bald assertion.
And Steven, I advise that you avoid bald assertions if you have any regard for your reputation as a scientist.

Man Bearpig

Mosher is not a scientist, unless a BA in English qualifies you as a scientist ?
http://www.populartechnology.net/2014/06/who-is-steven-mosher.html

TimTheToolMan

Mosher writes “What’s important is total forcing.”
What’s important is the possibility of an “internal” forcing.

Willis, all correct. Nicely and newly displayed this post. Well done. You reached the same conclusion as essay Blowing Smoke in ebook of same name published last year. Or my posts based on same on the previous thread. Nice to have further visual validation from a data hound such as yourself.
BTW, your rule of author count is something new (well, to me) but sure seems empirically validated here. Worth a larger statistical test.

Terry

Willis. Is the VEI the correct parameter to estimate the quantity of fine partic and sulphate/SO2. Im no vulcanologist, but I cant intuitively see the relationship. Surely it is the mass of those two (mostly) that is important not the VEI. Your thoughts ?

VEI takea no account of the composition of ejecta. Only the maximum altitude attainable.

bones

But VEI is correlated with the type of volcanism as is particulate ejections, which occur most heavily in volcanoes above subduction zones.

Willis Eschenbach

Terry January 9, 2015 at 9:32 pm Edit

Willis. Is the VEI the correct parameter to estimate the quantity of fine partic and sulphate/SO2. Im no vulcanologist, but I cant intuitively see the relationship. Surely it is the mass of those two (mostly) that is important not the VEI. Your thoughts ?

Good question, Terry. The answer is, the VEI is not really the correct parameter, but it’s the nearest and best we have. Charles Lamb had something he called the “DVI”, the Dust Veil Index, but it stops in (from memory) about 1988 or thereabouts, so it’s of no use to us for modern data.
Also, what Rud said.The VEI is a measure of power in the eruption, not the makeup of what is being ejected.
w.

Harry Passfield

Willis: I’m with Terry and Rud on this: If the ‘pause’ can be explained by volcanic activity it must surely be based on the sheer amount of ejecta that remains (stratospherically?) airborne after ejection.
But then, we surely must take into account that there is a possible delay between the eruptions and the effect they have on climate – if any. It seems inconclusive to me that the effects of any eruptions have an immediate and long-term effect on climate – which is supposed to be the aggregation of weather over a period of thirty years, or so I was told by people like Nick Stokes et al.

Harry Passfield

I should have read the comments further before posting. I see that Rud has made a similar observation further down the thread. Sheer cooincidence.

rishrac

So does that mean the heat is still hiding in the oceans? Skeptics are not the intended audience for the “it’s the volcanoes” line. Why would they think someone wouldn’t look at the number and size? Oh.. I know, the truly faithful. It has to be co2!!! It’s a villain just lurking around the shadows, just waiting. That tipping point must be around here somewhere.

TimTheToolMan

Willis writes “Well, the papers may be correct in their claim that the effect of eruptions on the clarity of the atmosphere may have been underestimated.”
Only with the assumption of a very high sensitivity…and there’s not a lot of evidence for that.
Its another case of “making stuff up” to suit their message.

philincalifornia

Willis, with regard to your FURTHER READING comment, you do know that she’s in the National Academy of Sciences, but then so is Peter Gleick. I’d like to think it’s actually an alarmist computer model for the NAS but, sadly, no.

michael hart

Some scientific journals report details of what was contributed by each listed author. Presumably this allows for a more open and honest apportioning of credit for ideas or work done. Or blame, should that later prove necessary.

This reply is not from Willis. But the general response is, wrong question.
Ejecta comprises many things. Example, Basaltic lava is not a major aerosol plume (Iceland at present).
VEI does not consider the nature of the ejecta, only the force ejected.That is why St. Helens ( VEI 5) had zero impact on atmospheric opacity measured at MLO. See essay Blowing Smoke in book of same name for details.
It is a combination of the force (will the plume reach the tropopause) and its constituents (lava, ash, aerosols) that determines whether and for how long an eruption might impact weather.
Since ‘climate’ is defined as the weather ‘envelope’ over at least 30 years, the whole Santer/Solomon volcano thingy is just nonsense. Unless you believe in supervolcanoes erupting for decades, nonstop. Well, the MSM does not report any of same!

Another points is where the volcanic eruptions actually are.
Volcanoes close to the tropics are able to disperse their ejecta further afield than volcanoes close to the poles, and also into the other hemisphere, which affects world temperatures more significantly.
Volcanos with more sulphur dioxide also apparently have a more significant effect than those with less. Eruptions vary significantly in the level of S02.
Let me guess, the papers don’t even bother with any of these things, let alone whether eruptions have changed in frequency and output pre and post ~2000.

Willis Eschenbach

Thanks, thingadonta, an interesting issue about tropic vs polar. I’ll take a look if I have time … so many clowns, so few circuses, and above all, so little time.
w.

High latitude lower VEI eruptions can reach above the tropopause simply because its lower. About 15-17km in the tropics, about 10 km in high latitudes.

John Andrews

Seems to me that the various authors may well have looked at the volcano activity data much as Willis has. It is very likely that they went no further because that data did not support their hypothesis. I wonder what they didn’t report.

Alan Robertson

…and if so, why were their assertions unchallenged during review?

Les Hack

Knowing your sense of humor, I could not help but notice Figure two giving an all-too-appropriate ‘finger’ to the results… what a wonderfully wicked display!

joelobryan

the value of a climate published study l should be the the inverse of the square of the numbers of listedcathors. I.e. (n authors) ^-2.

joelobryan

disregard above. I misread Willis’s inverse.

Matt

I disagree with Willis’ Rule of Author Count – what are you gonna do with the LHC folks that found the Higgs? There are 4000 of them, and to make it proper, all of them would have to be named… this is actually being discussed as a real problem for publishing the results 😉

John F. Hultquist

There is a difference. LHC folks are scientists. “Climate Scientists” don’t do science and know little about climate. See, that was easy.

+ something

“Climate” is to “scientist” as “witch” is to “doctor”.

Eric

flydlbee
+1000!
That is the best breakdown I have seen yet… take a respectable profession put another word in front and bingo it immediately is associated with insane ideas. A hundred years from now, hopefully less, people will look at Climate Scientists they same way we look at Witch Doctors today.

joelobryan

First they came for the LIA, then the MWP.
Now they make up excuses to come for the RSS and UAHbdata sets since 1979.

Katherine

whenever I see her name on a study, I’m sad to report that I just wince.
I have to say, me too. And hers wasn’t the only name on those studies that made me wince. So did Benjamin D. Santer (B. D. Santer).

Willis Eschenbach

And again sadly, I can only agree. Ben Santer’s name is another huge red flag for me.
w.

Hugh

I seem to remember a panic attack from the warmists a year or two ago about global warming causing increased volcanic eruptions.
So now: assume the truth of both that and this thesis that increased vulcanism is responsible for the pause.
We have a lovely balancing act.
Ain’t nature wonderful?

Greg

Nice simple analysis Willis. In fact they may be onto something if they were not so blinded by propping up their failed hypothesis.
Volcanoes are key IMO. But not the little ones. The problem is that they are ( in some cases wilfully ) ignoring long term WARMING effect of volcanoes.
The first clue is the cooling of the stratosphere that occured after both El Chichon and Mt Pinatubo. The smaller eruptions have no visible effect on this scale and the stratosphere is where they say they matter.
http://climategrog.files.wordpress.com/2014/04/uah_tls_365d.png
Having identified the timing of effect in the stratosphere, we can see the complementary warming of the surface record bears a striking resemblance.
http://climategrog.wordpress.com/?attachment_id=902
The bottom line is that it is the lack of volcanoes that explains the lack of warming compared to the previous 30 years.

Greg

PS , I say wilfully because Soloman who is a co-author on both papers has done extensive work on changes in ozone in relation to volcanoes. The drop in ozone after major stratospheric eruptions allows more shortwave energy into the lower climate and represents global warming “forcing”. There’s a link to one of her papers in the above linked article where they examine ozone and lower stratosphere temps.
Also both NCAR and IPCC recognise the step nature of the changes and hence their link to two major eruptions.
If they have not yet made the connection with “global warming”, one wonders why not.

Frank

Willis: The total number of eruptions is not important. Neither is the log mean annual VEI or the number of volcanoes with VEI <3. These are all straw men. The important factor is the number eruptions capable of transferring a significant amount of aerosol above the tropopause (where it will persist). The authors claim to have measured an increase in total aerosol since 2000 and claim it comes from volcanos weaker than the VEI 5 and 6 volcanoes that have traditionally been associated with cooling. That means you should have concentrated your analysis on volcanoes with VEI = 4. There were 14 volcanos with VEI = 4 between 2002 and 2011 and one with VEI = 5. Between 1900 and 1999, there were only 52 volcanoes with VEI = 4, 10 with VEI = 5 and three with VEI = 6. There clearly have been an unusually large number of VEI = 4 volcanoes during the hiatus than in earlier decades.
The key question is whether these previously ignored volcanoes resulted in higher levels of stratospheric aerosol than during earlier decades when VEI = 4 volcanoes were ignored. Most of the measurement techniques used during the hiatus were not available in earlier years. When the first paper was not behind a pay-wall, I thought that the methods that were used both before and during the hiatus gave contradictory results before the hiatus and therefore an ambiguous increase during the hiatus. The uncertainty in increase in aerosol forcing was about 50% of the total increase and this may have been a 25%-75% confidence interval.
A on-paywalled paper on this subject is available here: http://onlinelibrary.wiley.com/store/10.1029/2011GL047563/asset/grl28118.pdf

tty

Comparing VEI 4 eruptions in the early 1900’s with 2000-2010 is very doubtful. It is vary unlikely that we have a complete record of such small eruptions that far back. How good is the record of small volcanic eruptions for e. g. Ethiopia, the Subantarctic Islands or Kamchatka in 1900-1910?

Willis Eschenbach

Frank January 10, 2015 at 12:33 am Edit

Willis: The total number of eruptions is not important. Neither is the log mean annual VEI or the number of volcanoes with VEI <3. These are all straw men. The important factor is the number eruptions capable of transferring a significant amount of aerosol above the tropopause (where it will persist). The authors claim to have measured an increase in total aerosol since 2000 and claim it comes from volcanos weaker than the VEI 5 and 6 volcanoes that have traditionally been associated with cooling. That means you should have concentrated your analysis on volcanoes with VEI = 4.

Thanks, Frank, but the papers made no such claim. In fact, they didn’t mention VEI once, neither in the papers nor in the three Supplementary Online Information PDFs. So I fear it’s unclear where you got your claim about VEI = 4.

There were 14 volcanos with VEI = 4 between 2002 and 2011 and one with VEI = 5. Between 1900 and 1999, there were only 52 volcanoes with VEI = 4, 10 with VEI = 5 and three with VEI = 6. There clearly have been an unusually large number of VEI = 4 volcanoes during the hiatus than in earlier decades.

There were 16 volcanoes of VEI = 4 and above from 1995 to 2014 (most recent 20 years).
There were 17 volcanoes of VEI = 4 and above from 1975 to 1994 (previous 20 years)
Sorry, not seeing the “unusually large” difference.
In any case, the underlying problem is that even the largest volcanoes make so little difference in the global surface air temperature that they cannot be identified in the record unless you know what year they occurred in. You can’t find them by just looking at the record. See my previous posts in this regard, viz:
Overshoot and Undershoot
Prediction is hard, especially of the future.
Volcanic Disruptions
Dronning Maud Meets the Little Ice Age
Missing the Missing Summer
New Data, Old Claims About Volcanoes
BEST, Volcanoes and Climate Sensitivity
Volcanic Corroboration
Volcanoes: Active, Inactive, and Retroactive
Stacked Volcanoes Falsify Models
The Eruption Over the IPCC AR5
Volcanoes Erupt Again
Eruptions and Ocean Heat Content
As a result, I fear that the idea that small eruptions are the “cause of the pause” doesn’t pass the smell test.
w.

Danny Thomas

Shouldn’t we give credit where credit is due? After all, they did state:”One contributory factor”. /sarc

Frank

Willis: You say that the two decades from 1995-2014 had a normal number (16) of large volcanos (VEI 4 and greater), but that is irrelevant. There were ZERO large volcanos from 1995 through 1998 (when temperature was rising rapidly) and an unusual concentration of 13 large volcanos from 2002-2011 (most of the hiatus). The aerosols from the three large volcanos in 2011 persisted through at least 2012.
Why did I focus on VEI = 4 or greater volcanos? All but one of the eleven volcanos shown in Figure 1 of Rindley were VEI = 4. (I don’t know why the authors didn’t list all 13 large volcanos VEI 4 and 5 volcanos that occurred between 2002 and 2001, or why they included one with VEI = 3.)
During the period without large volcanos, measured levels of aerosols were low, near the detection limit. This period is the baseline from which the increase in aerosol forcing was determined, but the baseline is highly uncertain. New instruments provided more accurate measurement of the modestly higher aerosol present during the period of higher volcanic activity, but those new instruments can’t tell us how much forcing has changed (they weren’t available in 1995-1998) or what “normal” levels of volcanic aerosols were during the 20th century. So all estimates of how much cooling those 13 large volcanos produced from 2002-2012 are highly uncertain. A 95% confidence interval would probably include no cooling and therefore normally not form the central conclusion of a scientific paper.
To demonstrate that the number of VEI = 4 and VEI = 5 volcanos was unusual between 2002 and the end of 2011, I looked at the total number of such volcanos for the entire twentieth century: 53 VEI = 4 and 9 VEI = 5 (and 3 VEI = 6). VEI = 4 volcanos have not been detected more frequently in recent years, there were 32 in the first half of the century and only 21 in the second. So normal volcanic activity appears to consist of about one VEI=5 volcano per decade and 4-5 VEI=4 volcanos per decade, not the 13 from 2002-2011.

Frank

Willis: I’ve read your earlier posts on volcanos and clearly remember trying to “spot the volcano”. Unfortunately, monthly GMT is too noisy for the modest cooling expected from even the largest volcanos to be readily apparent. According to Paul_K’s summary at The Blackboard, Pinatubo supposedly reduced temperature by about 0.6 degC about six months after the eruption. About year earlier, the monthly CRUTEMP anomaly rose 0.6 degC between Feb and Mar 1990 and varied by 1.0 degC during the whole year. One needs to do a more sophisticated analysis than inspection by eye to see the transient effects of even powerful volcanos in noisy data. If you plot average annual temperature anomalies, you run into the problem that there was no volcanic cooling in the first half of the 1991 and less cooling in the second half of 1992. The climate plotter at Nick Stock’s blog formerly (but not currently) allowed you to plot monthly data with Gaussian smoothing over a selectable number of months. If you plotted monthly data with a Gaussian smooth over 13 months, the effects of Pinatubo and El Chichon were clearly visible. So if you really want to “spot the volcano”, I suggest you try that approach.
http://rankexploits.com/musings/2012/pinatubo-climate-sensitivity-and-two-dogs-that-didnt-bark-in-the-night/
The other thing you need to remember is that it takes time for volcanic aerosols to cool the earth and they dissipate long before equilibrium (ECS) is reached. In theory, the -3 W/m2 Pinatubo aerosol forcing would cool an Earth with a 25 m mixed layer at an initial rate of -0.1 degC/month. The Pinatubo forcing began to drop after about 6 months. As the planet cooled, Planck feedback diminished the effectiveness of the aerosol forcing.
Given that the 13 VEI 4&5 volcanos between 2002 and 2011 barely produced -0.1 W/m2 of aerosol forcing, I’m skeptical that they played an important role in the hiatus. However, a -0.1 W/m2 forcing for a decade is as important as a -1 W/m2 forcing for one year. I think it makes far more sense to question scientists ability to accurately quantify CHANGES in aerosol forcing that are less than 0.1 W/m2. IMO, it doesn’t makes sense to question whether there were unusual number of large volcanos during most of the hiatus.

Willis Eschenbach

Frank January 10, 2015 at 4:06 pm

Willis: You say that the two decades from 1995-2014 had a normal number (16) of large volcanos (VEI 4 and greater), but that is irrelevant. There were ZERO large volcanos from 1995 through 1998 (when temperature was rising rapidly) and an unusual concentration of 13 large volcanos from 2002-2011 (most of the hiatus). The aerosols from the three large volcanos in 2011 persisted through at least 2012.

I’m sorry, but your simple unsupported claim that it is “irrelevant” that the recent two decades have the same number of VEI 4+ eruptions as the previous two decades tells us nothing. The previous two decades were the time of rapid warming, and the recent two decades were almost no warming … but both periods had the same number of VEI 4+ eruptions. That’s very relevant to the claim that eruptions are the reason for the lack of recent wraming.
And your succeeding claim, that what is really relevant is the number of eruptions over a four year period, shows that your idea of “relevance” is … well … peculiar.

To demonstrate that the number of VEI = 4 and VEI = 5 volcanos was unusual between 2002 and the end of 2011, I looked at the total number of such volcanos for the entire twentieth century: 53 VEI = 4 and 9 VEI = 5 (and 3 VEI = 6). VEI = 4 volcanos have not been detected more frequently in recent years, there were 32 in the first half of the century and only 21 in the second. So normal volcanic activity appears to consist of about one VEI=5 volcano per decade and 4-5 VEI=4 volcanos per decade, not the 13 from 2002-2011.

What you are not taking into account is that in the earlier part of the 20th century, we didn’t have airplanes and satellites to detect every volcano, in particular the smaller eruptions. You can see this clearly by looking at the last two centuries of records of eruptions of VEI 4 or less, viz:

Note that the number of small eruptions doesn’t level off until 1950 … when airplanes became common and communications became rapid and detailed.
Now, we have two choices. Either the number of small eruptions of VEI 4 or less has been steadily increasing for 200 years … or we’re looking at a huge observational bias based on the fact that the further back we go, the fewer small volcanoes we noticed.
w.
[“number of small earthquakes of VEI 4 or less” or “number of small volcanoes of VEI 4 or less”? .mod]
[Fixed, thanks. -w]

Frank

Willis: When there are doubts that a cluster of VEI = 4 volcanos can cause a slight cooling, it makes no sense to include VEI 1-3 volcanos in the discussion. With current technology, we can watch a localized plume of aerosols enter the stratosphere at one latitude, gradually spread out over several months, and then fade away. All but one of the volcanos cited in this paper were large volcanos (VEI 4 and higher). The other, Soufriere
Hills (2006), is listed at VEI “4?” in one reference, but as 3 in the current Smithsonian table.
Out of the 52 VEI = 4 volcanoes in the 20th century, there were 11 MORE volcanos with VEI = 4 in the first half of the 20th century (32) than the second half (21). Therefore, there is no reason to believe that improved observations are responsible for the cluster of VEI = 4 volcanos from 2002-2011. This is especially true given the fact that there were ZERO VEI = 4 volcanos for five years in the late 1990’s. (Willis’s data shows that our ability to detect weaker volcanos has increased with time, but those weaker volcanos they don’t appear to be major contributors to stratospheric aerosol levels.)
Chance has presented us with an opportunity to compare a five-year period with no large volcanos (VEI 4-6) to a decade with an unusual concentration of large volcanos (12, VEI 4; 1, VEI 5). We have poor measurements that show that more aerosol was present when more large volcanos were occurring, but the forcing associated with enhanced volcanic activity was uncertain. The estimated cooling produced (0.05-0.12 degC, possibly a 25-75% confidence interval) doesn’t explain the pause.
It turns out that chance also produced a second cluster of large volcanos between 1980 and 1986: 2 with VEI = 5 (including El Chichon) and 7 with VEI = 4. Was there a suppression of warming warming during this period?

Willis Eschenbach

Frank January 11, 2015 at 2:17 am Edit

Willis: When there are doubts that a cluster of VEI = 4 volcanos can cause a slight cooling, it makes no sense to include VEI 1-3 volcanos in the discussion.

Frank: When there are doubts that VEI = 5 volcanos can cause a slight cooling, it makes no sense to include VEI 4 volcanos in the discussion.
All that they have shown is that SOME VEI 4 volcanoes may have a detectable (although very small) effect on the optical depth of the atmosphere … but we knew that already. They claim that there is also an effect on the clear-sky upwelling shortwave, but I find the evidence for this to be extremely weak. They disguise their lack of evidence in two ways. First, they don’t include all of the VEI 4 eruptions in their results. Here are the actual VEI=4 volcanoes, of which they’ve used six, plus one VEI 3 volcano for unknown reasons:

       Volcano.Name Start.Year Start.Month VEI
1            Ulawun       2000           9   4
2             Ruang       2002           9   4
4             Manam       2004          10   4
5            Rabaul       2006           8   4
6           Chaiten       2008           5   4
7             Okmok       2008           7   4
8         Kasatochi       2008           8   4
9     Sarychev Peak       2009           6   4
10 Eyjafjallajokull       2010           3   4
11           Merapi       2010          10   4
12        Grimsvotn       2011           5   4
13            Nabro       2011           6   4

Second, they smooth the CERES dataset that they are using with a centered smooth. And third, they don’t ever look at the global effect, only what they call “Near-Global (50°N-50°S)”. Their results show that only two out of their seven volcanoes had any detectable effect … not impressed.
If you think that such a change in two of the seven VEI 4 eruptions is significant, well, I guess we’re out of things to discuss.
w.

Frank

Willis: From reading Venier, I gather we can now track whether a concentrated plume of aerosols any volcano reaches the stratosphere, how it spreads first east-west and then globally, and then dissipates. Since only some VEI = 4 volcanos are listed, I conclude that not all of the inject material into the stratosphere. A table in Venier lists the Soufreier Hills volcano (VEI 3 in the Smithsonian table) as a “4?”. Whichever rating is correct, the paper has data showing that the concentrated plume of aerosol did reach the stratosphere.
So, not all VEI = 4 volcanos are the same and counting the numbers of such volcanos is a crude way to measure their potential impact on climate.

Willis Eschenbach

Frank January 12, 2015 at 1:04 pm

So, not all VEI = 4 volcanos are the same and counting the numbers of such volcanos is a crude way to measure their potential impact on climate.

Thanks for the comment, Frank, but their “potential impact on climate”? Seriously? Did you not read the update to the head post? Big volcanoes change the SAOD by something like 0.15, and their “impact on climate” is very small.
According to Santer, some VEI 4 volcanoes, the strong ones, change the SAOD by 0.002. This is about a thousandth of the change from a big volcano … and you are seriously claiming that this minuscule change may have some impact on climate?
Is this some form of climate homeopathy, where the tiniest dosage still has the power to create large changes?
In mystery,
w.

Of all the VEI 4 you note since 2000, only one affected optical depth measured by LIDAR at MLO. That was Surychev on the Kamchatka peninsula. It did so because a high latitude eruption where the tropopause is lower. Its aerosol plume was extensively studied; 95% washed out in 3 months. Details and references in essay Blowing Smoke.

Frank

Rud: MLO LIDAR data can be seen at the link below. Comment on the same page say:
“The changes to Versions C do not significantly alter previously published conclusions concerning this dataset by NOAA/ESRL authors, and strengthen the case for a general DECLINE in transmission (or transmittance) between 2000 and 2009.”
Figures 1-3 in Vernier (2011) indicate that we have a very good idea of which VEI 4 volcanos (and one VEI 5) are contributing aerosols to the stratosphere, at what latitudes, and for how long.
http://onlinelibrary.wiley.com/doi/10.1029/2011GL047563/abstract
What we don’t have a good idea of is how much aerosol in present – the data is very noisy. Even worse, we don’t know how much aerosols have changed, because many measurements are being made with systems that became available after 2000. In other words, we can’t tell if the low level of aerosols that we are able to measure in the 2000’s is different from normal background levels of aerosol that is usually present.

Did the burning of the Kuwait Oil fields ,which as a big event and went on from months, have any climate impact?

tty

No, except locally, smoke from fires stay in the troposphere and are quickly washed out by rain.

And that is why Carl Sagan pulled back a bit from his nuclear winter claims. He expected a huge effect from the fires, but it was much less than he expected. But thanks to Red Adair and human ingenuity the fires didn’t burn nearly as long as the doomsayers said they would.

Volcanoes are given bad name; overall they were and are beneficial for the evolution of life on this planet.

tty

Not when they are really large. Read up on the Siberian Traps and their effect on the biosphere. Or even Laki in 1783.

SandyInLimousin

Both Siberian and Deccan Traps are part and parcel of what the world is today; it is the major disasters that move evolution one step at the time.
Darwin thought that evolution is a smooth progression. It is not it is a saw-tooth escalator; each disaster is a temporary setback forcing surviving ‘inhabitants’ to adapt and move forward.
Vesuvius AD 79, Laki in 1783, Krakatoa 1883 and many others have done fair share of human life destruction, but then Genghis Khan or more recently Adolph H, Stalin etc. did even more so,.. I’ve gone off at a tangent there.

SAMURAI

As always, great post, Willis!
Facts are such stubborn things….
CAGW advocates seem to believe peer-review has magical properties that somehow turn hypothetical assumptions and presumptions into reality… Not so much…
My take on all the sudden interest in volcanoes is that large eruptions occur quite frequently (six major eruptions since 1750, for an average of around 2 or 3 per century), so by promoting the idea that large volcanic events have long-term and profound cooling effects on Earth’s climate, once the next one occurs, CAGW advocates can more easily blame the large eruption for CAGW’s complete inability to accurately predict global temps.
Ironically, Earth’s ability to quickly recover from the cooling effects of large eruptions is irrefutable proof that Earth’s climate is not as sensitive as CAGW advocates assert it to be…. This whole idea of climatic “runaway feedback loops” just doesn’t exist, because if they if they did, we wouldn’t be around to debate about it; a paradox.

Stephen Ricahrds

Willis, don’t you get bored with volcanos. I note our good friend from Duke has said exactly the same while mentioning your name.

Stephen Ricahrds

You would think that Santer would have had enough of being made to look the nincumpoop and bete du village. Banging your head against a wall begin to hurt after the first blow.

Speed

Stephen Ricahrds wrote, “You would think that Santer would have had enough of being made to look the nincumpoop and bete du village.”
But it pays well …
LLNL climate scientist Benjamin Santer wins DOE Distinguished Scientist Fellowship … Santer will receive \$1.25 million over five years contingent on his continued employment at Lawrence Livermore.
https://www.llnl.gov/news/llnl-climate-scientist-benjamin-santer-wins-doe-distinguished-scientist-fellowship
And of course there was that MacArthur Fellowship.

Paul

But it all pays the same..

Man Bearpig

Do you get a feeling there is going to be a new ‘revised temperatures’ moment? They will be claiming that without the volcanoes, the temperatures would be so much higher higher and would fit in exatly along the centre line of the models.

SkepticGoneWild

This is already being done for sea level measurements. University of Colorado Sea Level Research group provides satellite sea level data. However. the actual data is not a real measurement of sea level. They add a “glacial isostatic adjustment” because they say the ocean basins are getting slightly larger. What a crock of you know what. Imagine if you had a diving pool and filled it full, and the depth was 10 feet, Now let’s say you enlarged the pool by a factor of 2, with the same amount of water. Well, the new depth is now 5 feet. But NO. Not according to the University of Colorado. No, it’s still 10 feet deep. Dive right in! Oh the stupidity.

R. de Haan

The fact the authors are looking for a “reason” to explain “the Pause” IMHO is a remarkable feat on it’s own.
At least they no longer deny the warming has stopped.
So here we have this scientific conference in India claiming that AGW fears have been greatly exaggerated.
The AGW Titanic is hitting the iceberg.

The scientific answer? “Climate change deniers are upsetting the Fire Gods and making them erupt. Small volcanoes did not exist before 1998.”

Ignimbrite Lank

Most volcanoes are on the sea floor and erupt underwater. Many of these are not even discovered let alone documented when they are active. Gas from submarine volcanoes is either dissolved in seawater or bubbles to the surface unnoticed.
Another issue is that volcanoes vary considerably in type. Some can be very gaseous and others much less so. A relatively small volcano may release considerably more gas than a larger complex. For example many of the volcanoes along Africa’s Rift Valley are very high in dissolved CO2. These can produce huge quantities of gas during relatively small eruptions, many of which go unreported or not studied by vulcanologists.
There is too little known to make any useful estimates and I suspect that many more active volcanoes will be discovered before any meaningful estimates for gaseous emissions.

ivor ward

“”The AGW Titanic is hitting the iceberg.””
At the moment the iceberg appears to be made of soft fluffy absorbent lint.

Stephen Ricahrds

Or rotten ice.

Old Goat

It occurs to me that any global warming has apparently ceased. You surely can’t say it has “paused” until, at some time in the near or distant future, it restarts. Expectation is not really good enough.
The fact that everyone and his brother are postulating reasons from the sublime to the ridiculous for this cessation, is laughable. Nobody really knows, other than with the benefit of history.
The climate does what it does, does what it always has done, and always will do – change, we can never stop it, accidentally or deliberately.
Whilst it is in amiable mood, and we are comfortable, why worry? We could do with it getting a bit warmer, but the portents appear to suggest the opposite. Instead of “preparing” for a warmer world, wasting time and money on stupid efforts to alter the future (we can’t, with climate), maybe we should be more concerned with the fact that the planet isn’t warming significally, hasn’t for some considerable time, and with the hindsight that we possess, consider what we should be doing in an effort to protect ourselves from the likely coming cold. We know that the globe cyclically warms and cools, we also know that the latest Holocene interglacial is cooler than the previous Eemian. Why are we involved in so much expenditure in going in the wrong direction, inevitably to shoot ourselves in both feet?
I’m not a scientist, or an expert – merely an interested layman, who makes his own observations.
I don’t often post here, but I am concerned.

lgl

Willis
Thank you for once again showing the importance of volcanoes.
Using your fig.2 it’s around 0.2 degC/LogMeanVEI, so Santer is probably right.
(note high VEI gives longer delay, ~3yrs, the eruptions late 2000 were weak, short delay)

Willis Eschenbach

Sorry, lgl, but that graph is totally unintelligible. What is the upper line, and where did it come from?
Also, the curious part is that your upper line starts to go down well before there is any increase in VEI. Take a look at about 1987, where it starts to drop … if the upper line is temperature, is the drop starting in 1987 causing volcanoes in 1990 and 1991?
w.

rgbatduke

Surely you aren’t going to insist on a silly little thing like temporal ordering or an actual correlation between the events and top-of-troposphere measurements of total broadband insoolation, Willis…;-)
I do have one comment to make on your graph, though. When you plot average VEI per year, the year 1990 has an average VEI under 5. Yet Pinatubo was 6. I have a hard time seeing how the cumulative average for the year can be less than the peak contributor — you aren’t finding the average VEI per volcano, you are finding the average VEI of the year. Are you dividing this out by months or something? That would drop VEI by a factor of 10, agreed, but I’d argue that when presenting annualized data there is little point in plotting the annual average of the VEI per month. Just do total VEI per year, which would make Pinatubo-Hood 2 units higher, over 6 and not over 4. This is actually perfectly sensible, given that VEI is associated with total volume of ejecta and the lifetime of this ejecta is order of a year and not order of a single month. Maybe one would do better with a six month or three month average (which would reveal the decay structure and hence provide a better match to ML transmittivity data) but in an annual presentation, why not use annualized data? You seriously misrepresent the VEI of the year’s events and to be honest, even the factor of 10 is not enough — Pinatubo/Hood is two orders of magnitude low, not one. So I don’t quite see how you arrive at the numbers in the plot. I think the signal should be much larger than the noise.
Finally, what’s the spike in 2010? All I see in my major eruptions data is four VEI 4s in 2010 and 2011 combined, and sadly, on a log scale even all four 4’s do not even a 5 make (let alone only two per year in a single year peak) and yet this single year peak is commensurate with El Chichon or Mt St Helens. So exactly how, again, did you get the average VEI result? Am I missing something?
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Willis Eschenbach

rgbatduke January 10, 2015 at 10:44 am

I do have one comment to make on your graph, though. When you plot average VEI per year, the year 1990 has an average VEI under 5. Yet Pinatubo was 6. I have a hard time seeing how the cumulative average for the year can be less than the peak contributor — you aren’t finding the average VEI per volcano, you are finding the average VEI of the year.

If this is intended for me, I don’t understand it at all. The average of a series of numbers is ALWAYS less than the peak contributor. And I am finding the average VEI for the year.

Finally, what’s the spike in 2010? All I see in my major eruptions data is four VEI 4s in 2010 and 2011 combined, and sadly, on a log scale even all four 4’s do not even a 5 make (let alone only two per year in a single year peak) and yet this single year peak is commensurate with El Chichon or Mt St Helens. So exactly how, again, did you get the average VEI result? Am I missing something?

The spike is in 2011. During that year there two VEI 4s and a VEI 5. Because the average is logarithmic, the larger values dominate the average, giving an annual average of just under four.

So I don’t quite see how you arrive at the numbers in the plot.

For each year, because the VEI is a logarithmic scale, I took a logarithmic average. I took 10 ^ VEIs, took the average of those numbers, and then took the log of the average.
w.

gaelansclark

Upside down tiljander…..nice mannian mosh-up…

Mosh-up, that’s funny…

Stephen Ricahrds

Fascinating. A different version of inversion corruption. First Tiljana upside down now volcano in the mirror. Whatever next ? Upside down -mirror image, perhaps?

Upside down and backwards! How is this even done? And why…

Eric

I think you forgot the /sarc tag…
If that ridiculous overlay that you mocked up were true, why does the temp anomaly start dropping in ~2004 when there hadn’t been a change in volcanic activity since 1993? Or did the Earth anticipate the coming increase in 2008? /sarc (<—- see how that's done..)

lgl,
Why did you post your chart upside down and backward?

lgl

There is a negative correlation between VEI and temperature and then it is better to flip one of the charts to show the correlation, standard procedure. But it isn’t backward.

mwhite

Regarding Stratospheric eruptions, Spaceweather.com had a story (backend of 2010)
“ALL-CLEAR IN THE STRATOSPHERE”
http://www.spaceweather.com/swpod2010/18dec10/twostratospheres_strip.gif
“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.”
http://spaceweather.com/archive.php?view=1&day=19&month=12&year=2010
“The lunar eclipse record indicates a clear stratosphere over the past decade, and that this has contributed about 0.2 degrees to recent warming.”

rgbatduke

Which fairly precisely matches the Mauna Loa data, BTW. Since 1996 and the full decay of Pinatubo/Hood ejecta, Mauna Loa has measured a nearly constant broadband atmospheric transmittivity of $0.93 \pm 0.01$. I disagree with the conclusion that this has contributed to “global warming” as this is obviously the dynamical equilibrium transmittivity of the atmosphere and is a remarkably stable constant except for perturbations from major volcanoes. However, even the major volcanoes have almost no resolvable effect on global temperature given the much larger variations due to things like ENSO, CO_2, and unknown dynamical factors.
At best you should say “0.2 degrees of presumed recent warming in recovery from presumed Pinatubo cooling”, but the data does not really support this assertion — Pinatubo cooling was at most 2-3 years and was already “done” by 1996 and obviously was completely swamped by Super-ENSO warming in 1997-1998 which reset the global climate state to make any ceteris paribus argument moot by warming up PAST any imagined new equilibrium and then falling back. But one cannot really see any climate effect of the mild drop of transmittivity in the early 1960s — the 60’s cooling started almost 20 years earlier after the peak in the 1940s and there is no correlation in the local transient or systematic trend. There is no response at all to the 1980’s majors. Only the Pinatubo/Hood double whammy MAYBE influenced temperature for a couple of years. Maybe.
So first, one has to establish that top of troposphere insolation has any appreciable impact on global average temperature even when it drops by as much as 5% for periods as long or longer than a full year.
I think what this is all leading to is that a mix of dynamic feedback from clouds and the enormous buffering capacity of the oceanic heat bath are going to end up cancelling almost any effect from things happening above the mid-troposphere up to and including variations in the integrated top of troposphere insolation, and will turn out to have dynamic response times on the order of decades plural — maybe even a century. Response to CO_2 is better supported by the data, although in a multivariate nonlinear chaotic dynamic system it is difficult to be certain in one’s attribution of effect to cause. Personally I think a nonzero, positive total climate sensitivity is very well supported by the data (with some considerable range of argument still as to what the specific number might be) but I freely admit that I can’t solve the coupled Navier-Stokes equation in MY head, either, and all the variation we observe could be pure nonlinear dynamics that laughs at CO_2 as much as the climate apparently laughs at 5% variations in TOA insolation.
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milodonharlani

By Hood, do you mean St. Helens, the nearly perfectly Fuji-like conical volcano which spectacularly committed seppuku in 1980, tragically taking my brave friend & former student Reid Blackburn with it? The one named by CPT Vancouver for his diplomat pal rather than by LT Broughton for ADM Hood.

rgbatduke

Oops, no, I mean Mount Hudson, in Chile, which also erupted in 1991 — sorry, Hood, Hudson, Helens, I get confused.
http://en.wikipedia.org/wiki/Mount_Hudson
It was largely ignored because of the more spectacular Pinatubo, but it was a VEI 5 eruption (which is “significant”) and was characterized by a high sulfur dioxide emission — lots of aerosols.
That is one of the catches in all of this analysis, BTW. VEI is not terribly well correlated with aerosol emission — note the complete difference between Mt. St. Helens (VEI 5, not much aerosol) and El Chichon (also VEI 5, but with a huge aerosol contribution, almost comparable to Pinatubo and Hudson combined. There is a nice graphic here:
http://en.wikipedia.org/wiki/Mount_Hudson#mediaviewer/File:TOMS_SO2_time_nov03.png
illustrating part of the problem. Note well the log scale — even though there are some clusterings, only the peaks matter because the integrated aerosol contribution on a LINEAR scale is going to be utterly dominated by the few peaks in this graph. So don’t be misled by the apparent clustering of low intensity events on the right — add them all up they don’t equal a single addtional bar in the 100-1000 range, let alone the very few bars that reach the 1000-10000 range that seems to actually show up on Mauna Loa. Of the events on this graph, only El Chichon and Pinatubo/Hudson show up on Mauna Loa. The entire 1996 to the present stretch is flat, suggesting that whatever the integrated aerosol emissions of the volcanoes in the right hand part of this graph (and beyond) they have no observable impact on stratospheric reflection and are quite irrelevant to the apparent near-cessation of warming.
It is also clear that there is more than “just” aerosol emissions that matters. The lack of any signal from the 1979-1980 cluster, with a highly emissive VEI 3 (Sierra Negra) and a comparatively non-emissive VEI 5 (Mt St Helens) suggests that one probably needs a lot of SO_2 AND a major blast to get it up into the stratosphere to have much impact. This of course means that we can even MORE strongly ignore the collective emissions of the VEI 3 or less volcanoes, and probably can ignore most 4’s and about half of the 5’s. The SO_2 from wussy little volcanoes probably never reaches the stratosphere — it is turned into acid rain long before it gets that high (remember, it is heavier than even CO_2 which is already heavier than O_2 and N_2, so it experiences if anything a slightly negative net atmospheric buoyancy, and is highly water soluble. In fact one way in which it (and other aerosols) cool is by nucleating clouds in the lower atmosphere. Which is plausible and can occur even from comparatively weak volcanoes over large regions where the concentration is NOT well-mixed. So I don’t quite understand why anyone would hypothesize a nonexistent connection to stratospheric tranmission.
It also provides us with a plausible reason for the warming of the 1980s. There are a reasonable number of LARGE emissions across the fifteen years from 1987 to 1999, but there was actually a dearth of smaller high SO_2 contributors. This could have combined with high solar activity (and hence low radiation AND slightly higher solar constant) to cause some fraction of the warming over this exact stretch. In that sense, weak vulcanism COULD be a cause for cooling or neutralization of warming or whatever, not from the integrated VEI but from the NONlinear effect of the SPATIALLY DISTRIBUTED collection of small emitters.
To put it another way — a 20 kiloton nuclear device exploded at one place does far, far less damage than 20,000 one ton conventional devices spread out over a much larger area, which does still less than 40,000,000 pounds of TNT with e.g each building in a city containing just one pound. This process cannot continue indefinitely because one has to exceed the threshold where the shock front can knock stuff down but it illustrates the point. 10 VEI 5 eruptions happening at 10 different places on the planet very likely have a larger impact than 1 VEI 6 at one place IF one isn’t assuming “well mixed” impact but instead are looking at the localized area that is strongly impacted.
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milodonharlani

Thanks for clarifying & for mentioning Hudson, which I´ve seen.
Sent from Chile.