# Volcanoes Erupt Again

Guest Post by Willis Eschenbach

I see that Susan Solomon and her climate police have rounded up the usual suspects, which in this case are volcanic eruptions, in their desperation to explain the so-called “pause” in global warming that’s stretching towards two decades now. Their problem is that for a long while the climate alarmists have been shouting about about TWO DEGREES! PREPARE FOR TWO DEGREES OF DOOM BY 2100!! But to warm two degrees by 2100, you have to warm at 0.2°C per decade, or around 0.4°C during “the pause” … so they are now left trying to explain a missing warming that’s two-thirds of the 20th century warming of 0.6°C. One hates to confess to schadenfreude, but I’m sworn to honesty in these pages …

In any case, I got to thinking about their explanation that it wuz the volcanoes what done it, guv’nor, honest it wuz, and I did something I’d never thought to do. I calculated how much actual loss of solar energy occurs when there is a volcanic eruption. I did this by using the Mauna Loa atmospheric transmission data. These observations record what percentage of the solar energy is being absorbed by the atmosphere above the observatory. I multiplied this absorption percentage by the 24/7 average amount of solar energy (after albedo) which strikes Mauna Loa, which turns out to be 287 W/m2. (As you’d expect from their tropical location, this is larger than the global average of 240 W/m2 of sunlight after albedo). Figure 1 shows that result, which was a surprise to me:

Figure 1. Amount of solar energy absorbed by the atmosphere above Mauna Loa, Hawaii. Data Source

Now, before I discuss the surprising aspects of this graph, let me note that the Mauna Loa data very sensitively measures the effect of volcanic eruptions. Even small volcanoes show up in the record, and the big volcanoes are clearly visible. Given that … is there anyone out there foolish enough to buy the Susan Solomon explanation that the cause of the pause can be found in the volcanoes? I guess there must be people like that, the claim has been uncritically accepted in far too many circles, but really … who ya gonna trust? Susan Solomon, or your own lying eyes?

I’ll return to the question of the pause, but first let me talk of surprises. The thing that was surprising to me in this was the size of the loss of solar energy. The El Chichón and Pinatubo eruptions reduced the downwelling solar energy by maxima of forty and thirty watts per square metre at Mauna Loa. This is a huge reduction, much more than I would have guessed.

One measure of how much energy is lost is the total loss until such time as the absorption returns to its pre-eruption value. It turns out that in the case of both El Chichon and Pinatubo, the net loss of solar energy was about 450 watt-months per square metre. The loss was spread more widely (5 years) in the case of El Chichon than in the case of Pinatubo (3 years) before it returned to normal.

This means that for the period 1982-1987, Mauna Loa was running at 450 W-months/m2 divided by 60 months equals an average deficit of no less than 7.5 W/m2 of incoming energy over the five-year period … and it’s worse for Pinatubo, since that involved the same total energy but only lasted for three years. So for the three years from 1991-1994, Mauna Loa was running at a whacking great average solar energy deficit of 14 W/m2 …

Now, how much difference did this surprisingly large lack of incoming energy make? According to the IPCC, climate sensitivity is 3° per doubling of CO2, and a doubling of CO2 is a forcing increase of 3.7 W/m2 … and Mauna Loa was running at 14W/m2 shy of normal, that’s almost four doublings of CO2. So according to the IPCC, that kind of a decrease in forcing should have lead to a temperature drop of 11°C … so what actually happened?

Well, we’re in fantastic luck, because the temperature records at Mauna Loa are very good. Here’s what they say (study here):

Figure 2. Mauna Loa temperatures. Vertical red lines show the dates of the El Chichon (March 1982) and Pinatubo (June 1991) Graph from B. D. Malamud et al.: Temperature trends at the Mauna Loa observatory, Hawaii.

As you can see, despite the large decrease in incoming sunshine, there is absolutely no visible change in either the noon or the midnight temperatures … go figure. What happened from the volcano is nothing at all. No effect.

Now, y’all may recall that I have argued over and over against the concept of climate sensitivity. This is the widely-accepted hypothesis that the changes in temperature are determined by the changes in forcing. I’m a climate heretic—I don’t think climate works that way at all.

In particular, despite widespread skepticism, I have persisted in saying that volcanoes basically don’t do jack in the way of affecting the global temperature. I can finally demonstrate that unequivocally because I’ve stumbled across a very well-documented and precisely measured natural experiment.

At Mauna Loa we have a clear example of a measured decrease of 7 W/m2 in the average incoming solar energy for five years (1982-1987), and a decrease of 14 W/m2 for 3 years (1991-1994) … and there is absolutely no sign of either forcing decrease in the temperature record of the very place where the solar decrease was measured.

As I’ve said over and over, the emergent phenomena of the climate system respond instantly (hours or days, not months or years) to any change in the temperature. If it cools, we rapidly get a drop in albedo, which allows in more sun, and the balance is restored. If it warms, very soon thereafter albedo increases, we get less sun, and again the balance is restored. So while I was surprised by the size of the drop in downwelling solar energy, I was not surprised that we can’t find the signal of the solar drop in the temperature records.

Setting that question aside, let me return to the “pause”. Solomon et al. used the Vernier aerosol optical depth (AOD) dataset, which is available here. It is a calculated global dataset based on various observations. The explanation of the calculations is here. If anything, there is less recent variation in that dataset than in the Mauna Loa dataset. Figure 3 compares the two over the period of the satellite temperature observations.

Figure 3. Compares the negative of the aerosol optical depth with the Mauna Loa transmissivity data. Mauna Loa data rescaled to match AOD data for comparison purposes only.

So it doesn’t much matter which one we use to compare to the temperature data. Let me use the Mauna Loa transmissivity data, since the native units are in the same range as the temperature anomaly. Figure 4 shows the comparison of the Mauna Loa transmission data with the UAH MSU satellite-based lower troposphere temperature data:

Figure 4. Satellite lower tropospheric temperatures (blue) and Mauna Loa solar transmission (black line). Note that while Pinatubo happened at the start of a temperature drop, El Chichon happened at the start of a temperature rise. In addition, in neither case are the rise or the drop notable—the drop 1988-1989 or 2007-2009 is indistinguishable from the post-Pinatubo drop.

Finally, lest some folks claim that because Mauna Loa is in the northern hemisphere we can’t compare it to the global temperature changes, Figure 5 shows the comparison of the Mauna Loa with the northern hemisphere temperatures:

Like I said … I know there must be folks out there that can be convinced that the changes in the black line, the known effects of the volcanoes, are the reason that there is a “pause” in the global temperatures … I’m not one of them.

CONCLUSIONS:

• I may never find better evidence of the lack of connection between changes in forcing and changes in temperature than the measured large drop in solar forcing and the total lack of corresponding temperature change at Mauna Loa. It is a superb natural experiment, and has been very precisely measured for over half a century. It provides strong evidence in favor of my hypothesis that the temperature is controlled by emergent phenomena, and has very little to do with forcing.

• The change in forcing from the 21st century volcanoes is trivially small in both the Vernier AOD dataset and the Mauna Loa dataset. It is far too small to have the effect that they are claiming. I don’t care what the climate models told Solomon et al., the post-2000 changes in volcanic forcing are meaningless.

• My oft-repeated claims about the lack of effect of volcanoes on the global temperature are completely borne out by these results.

My regards to all,

w.

AS ALWAYS: If you disagree with me or anyone, please quote the words you disagree with. That way we can all know exactly what it is you have a problem with. Vague handwaving claims go nowhere.

MAUNA LOA TRANSMISSION DATA: From their website

The “apparent” transmission, or transmission ratio (Ellis & Pueschel, Science, 1971), is derived from broadband (0.3 to 2.8um) direct solar irradiance observations at the Mauna Loa Observatory (19.533 ° N, 155.578 ° W, elev. 3.4 km) in Hawaii. Data are for clear-sky mornings between solar elevations of 11.3 and 30 degrees.

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## 156 thoughts on “Volcanoes Erupt Again”

1. Is it possible that volcanoes cause more outgoing energy to be absorbed so temperatures go up?

Ore more incoming UV to be absorbed. Or more incoming IR?

It appears to me that more volcanic eruptions cause warming.

2. Willis,
I’m not arguing with what you say here, but maybe with something unsaid. The light which was not transmitted, accounted for as a transmission drop, has one of two other paths to take: (1) It can be reflected back to space; or (2) it can be absorbed. The first should result in less net heating. The second will have little direct effect upon heating. (Indirectly, the aerosols might participate in a so-called greenhouse effect, but I don’t know their spectral characteristics.)

Can your results be taken to support the absorption path?

3. bones says:

Willis.
As has often been the case with your work, this needs to be in a major science journal for all the world’s scientists to see. Of course I understand your reasons for not wanting the hassle of dealing with the gatekeepers, but it would be nice to remove the blinders from the science herd animals.

4. BoyfromTottenham says:

Hi from Oz. Really nice work Willis – now get back to that framing job! ;-)

5. george e. smith says:

Well like I have said; “It’s the water !”

Less sun, get’s cold, more rain, less clouds, more sun, gets warm; and verse vicea. It’s called negative feedback.

How many times has Dr Svalgaard told us, it ISN’T the TSI. (or the volcanoes.)

6. philincalifornia says:

Are these people not speaking to each other:

Travesty Trenberth: The missing heat’s hiding in the deep oceans, ooooh errrr hold on a sec – it comes out and causes heatwaves occasionally, but only when they’re in the news.

Tamino: There is no pause in anthropogenic global warming. Just look at my statistical treatment, not to mention my mom and sister’s praise in the comments section telling the world what an ace scientist I am.

Solomon the Wise: It were the volcanoes wot did it. Honest.

LA Times Editor: Waaaaaaaah, I’m taking my ball home you horrid d*niers.

Jones: Fk off, leave me alone, can’t you see I’m in hiding.

Mann: Sue them, that’ll shut them up.

Cook: OK, I admit, I’m just a f-kin idiot.

Oreskes: Put them in jail on RICO charges, that’ll shut them up.

6-year old girl: Mommy, the Emperor has no clothes.

Nobody: The hard scientific evidence that atmospheric carbon dioxide going from 280 ppm to 400 ppm has any measurable effect on any climate parameter is as follows:

Bullet point 1 ……

7. Pamela Gray says:

The animation shows the emission and transport of key tropospheric aerosols from August 17, 2006 to April 10, 2007. It shows the aerosol optical thickness of black and organic carbon (in green), dust (in red/orange), sulfates (in white), and sea salt (in blue) from a 10 km resolution GEOS-5 “nature run” using the GOCART model.

http://gmao.gsfc.nasa.gov/research/aerosol/modeling/nr1_movie/

Now add to that the now and then event of a volcano. It just can’t match the huge continuous dust storm out of Africa. What happens when the Trade Winds pick up and the air is dryer? More dust! A lot more dust! Hmmmmmmmm

By the way, this dust fertilizes the Atlantic equatorial ocean. And it probably has an oscillation to it.

8. Nancy C says:

obligatory request for watt months/m^2 to be converted into the more familiar hiroshima units, please.

9. cynical1 says:

They sure have erupted.
Mann goes after Andrew Bolt!

Steyn smiles. He knows a lawyer to recommend.

10. If there is significant number of active, new active volcanoes during this solar minimum, we may lose the fight for true science of climate in our lifetime.

But we know to stack the wood high and long during a solar minimum.

Goood bye to the Alarmists either way. It’s all about Ice Ages.

Paul

11. Thanks Willis for this observational debunking of the radiative forcing concept.

There is a simple explanation for all of this & why the Earth surface temperature has little to do with radiative forcing, and is primarily determined by thermodynamics [convection, phase change, pressure, etc], not radiation.

1. The surface temperature, as well as the entire atmospheric temperature profile, is entirely explained by solar insolation plus the behavior of adiabatic gases in a gravity field, which establishes the wet and dry adiabatic lapse rates.

2. The dry adiabatic lapse rate equation: dT/h = -g/Cp [g is gravity, Cp is heat capacity of the atmosphere] does not have a term for radiative forcing and is independent of radiative forcing.

3. Addition of GHGs increase the heat capacity Cp, which causes a decrease in the lapse rate, as is observed: the dry lapse rate is much steeper than the wet. A decrease in the lapse rate causes a cooler surface.

4. The entire 33K “greenhouse effect” is entirely explainable by the average adiabatic lapse rate i.e. the observed average lapse rate = 6.5K/km * 5 km = 33K. The 255K equilibrium temperature with the Sun at the TOA + 33K due to the lapse rate sets the surface temperature at 288K or 15C

5, Thus, a large volcanic eruption or large change in RF doesn’t change surface temperature, because there is no effect on the average lapse rate, and no change of the equilibrium temperature with the Sun at the TOA.

12. highflight56433 says:

Does this negate the nuclear winter theory?

13. Louis Hissink says:

Let me get this straight. The pause is due to additional volcanic activity which increased the aerosols which caused the cooling, while at the same pumping additional CO2 into the same atmosphere from the same volcanos.

And they accuse us of being delusional?

14. GeologyJim says:

Another elegant contribution, Willis. You have a knack for going right to the observational data, whereas the “modeling clowns” twiddle another partial differential or jigger another parameterization exercise.

Volcanoes never maintain eruption cycles long enough to change “climate” (that 30-year so-called standard). And clearly ash and sulfates and whatever get cleansed out of the atmosphere in a couple of years anyway.

Solomon is in a “double ethical bind” (to borrow a famous Stephen Schneider line). She has claimed that CO2 persists for hundreds of years in the atmosphere (the “heat in the pipeline” boogeyman) , and yet here we are with 17+ years of rising CO2 and not a whit of temperature rise to show for it. That’s what Kevin calls “a travesty”. Rational minds call it evidence of a failed hypothesis.

Susan also blew the fluorocarbon-ozone thingy years ago. I think it’s pretty clear now that ozone over the poles is just a seasonal oscillation.

Like Ehrlich, Solomon will be lionized by environmentalists despite a persistent track record of error and failure, because they claimed human cause for perceived calamities. Rachel Carson, on the other hand, was not only wrong about DDT – – her ideas led to millions of unnecessary deaths of tropical children.

That might be labeled an “emergent phenomenon” of a most perverse variety.

15. Espen says:

Very interesting! To further test the theory, I’d suggest looking at inland stations where there’s no ocean thermostat. I guess the global/NH temperature chart already suggests you’ll find nothing (El Chichon did not cause a drop), but still worth a look I think.

16. François says:

I don’t understand your arithmetics, when you are trying to find .6 degrees missing when it really should be only .4. There is a reality, come to Paris and I will show you olive trees blooming there, that would never have occurred fifty years ago. What is your explanation? urban heat island effect? We are just like the Brits, we stopped using coal to warm up our houses years ago, we are not more wasteful of energy than any other capital-city inhabitant. Paris is warmer than it was before. So are the surrounding areas, up to a thousand km away from there (ours is not such a huge country, but there is a bit of room around…).

17. Steven Mosher says:

“The “apparent” transmission, or transmission ratio (Ellis & Pueschel, Science, 1971), is derived from broadband (0.3 to 2.8um) direct solar irradiance observations at the Mauna Loa Observatory (19.533 ° N, 155.578 ° W, elev. 3.4 km) in Hawaii. Data are for clear-sky mornings between solar elevations of 11.3 and 30 degrees.”

two clues here.

18. Nemo says:

Curious to see if there were any changes in humidity and/or rainfall at that location for the volcano affected time periods. Greatly despise thinking of everything in terms of ‘temperature’ as that does not equate to energy, at least not entirely. Quick search brought up a west Hawaii stations 12 month moving mean here:http://hi.water.usgs.gov/recent/westhawaii/rainfall.html. The naked eye doesn’t see anything I can attach to the Pinatubo eruption, and the graph doesn’t go back far enough for El Chichon. There appears to be a step from one mode of operation to another in ’92, though I wonder how much of that is actual data and how much of that is % based moving mean. Have to pull the raws down.

Also am considering that the feedback effects from cloud/albedo affects described break down in extra tropical areas, particularly NH landmass. Too late to poke into it atm, but the thinking goes that tropical areas already exist in a negative feedback scenario. As such, less sunlight would be reflected in a change to the feedback mechanism but not greatly affecting the ground level temperature. However, the lower energy areas such as the North/South Atlantic and Indian oceans, or especially the continents, would not react the same way to lower sunlight input because they largely operate below that threshold already, right? If so you would expect to see a positive feedback emergent phenomenon, where applicable.

Concern is that the negative feedback is powerful and persistent thanks to tropical cloud cover, as described, but an extra tropical positive feedback phenomenon may not be. Or I could simply be lacking sleep.

19. Curt says:

Even if you accept, at least for the sake of argument, that the major volcanic eruptions, and the resultant reduction in insolation at the surface, did cause cooling, we have not seen any of these during the “pause”.

Until now, the climate establishment claimed that the more minor volcanic eruptions did not have long lasting effects, because their plumes did not get high enough to avoid being quickly rained out. Only the really major eruptions sent their plumes into the stratosphere, where the effects are long lasting. I’ve been trying to figure out how this wisdom has changed recently…

20. pat says:

one of the funniest things i’ve ever read on our “academics” website in Australia!

24 Feb: The Conversation: University of Utah: Human well-being leaves large carbon footprint
Improving life conditions for humans has been linked to increased carbon emissions.
Professor Andrew Jorgenson’s research measured the carbon intensity of human well-being (CIWB) by using the ratio between per capita carbon dioxide emissions and average life expectancy at birth — for 106 countries over the period 1970–2009.
The largest CIWB was found to be in North America, Europe and Oceania, but generally increased across the board.
Jorgenson says that as long as societies rely on fossil fuels, achieving better life conditions will drive up carbon emissions worldwide.
Read more at the University of Utah…
2 COMMENTS ONLY:
Gerard Dean:
Amazing! Who would have thought that raising human living standards through the use of fossil fuels to create electricity, gasoline, diesel and gas would increase our carbon footprint.
Our ancestors learnt how to light a fire for warmth, then to cook and to light their nights. Noticing a funny rock that melted lead to smelting of metals and it took off from there.Then we found coal, then oil and finally uranium.
It is blindingly obvious that humans improve their living conditions by burning more stuff dragged out of old mother earth.
Can I have my PhD now?
Professor Andrew Jorgenson
Dear Gerald Dean,
Perhaps before making such flippant remarks you should first read the research article as well as the supplemental materials. I’d be happy to send you both.
Regards,
Andrew Jorgenson
http://theconversation.com/human-well-being-leaves-large-carbon-footprint-23620

21. Mario Lento says:

Thank you Willis!

22. Willis Eschenbach says:

Steven Mosher says:
February 24, 2014 at 10:16 pm

“The “apparent” transmission, or transmission ratio (Ellis & Pueschel, Science, 1971), is derived from broadband (0.3 to 2.8um) direct solar irradiance observations at the Mauna Loa Observatory (19.533 ° N, 155.578 ° W, elev. 3.4 km) in Hawaii. Data are for clear-sky mornings between solar elevations of 11.3 and 30 degrees.”

two clues here.

Steven, it’s usually good to hear from you … you are a smart fellow.

However, when you get into your cryptic one-liner mood, you’re worse than useless. Let me kindly request that you say what’s on your mind, and leave off the cutesy sound bites. They’re not working.

What are the two clues, what do you conclude from the clues, and what does it have to do with my post?

Even if I could figure it out for myself (obviously I can’t), I’d still be missing your thoughts, insights, and illumination. So if you’ve got something to say … how about you give us the benefits of your understanding?

w.

23. Truthseeker says:

So, how many times do these people call “wolf” before the everyone ignores them?

24. Peter Hessellund Sørensen says:

I agree with your conclusions here but I think it is fair to mention that there is not necesarily a linear relation between size of volcanic eruption and changes in temperature. Som of the large prehistoric volcanic eruptions might have had large effects on temperature simply because they were so large that they reached a treshold size. Another thing is that volcanoes are very different. The Pinatubo for example was a short explosive eruption throwing large amounts of dust into the atmosphere whereas the Laki eruption on icland lasted a year or so but was primarily lava flows and emissions af gasses like sulfuric fumes. Historic records show a large climate effect in Northern Europe during the Laki eruption and the harvest is reported to have failed for several years. This eruption was so big that the smell of sulfur reached Denmark a distance of almost 2000 km.

25. Espen says:

François – you’re right that Paris was cooler 50 years ago. But what about 80 years ago? My guess: It probably was almost the same as today. I found some temperatures here: http://www.tutiempo.net/en/Climate/Paris_Le_Bourget/71500.htm and plotted them: http://espen.vestre.net/tmp/paris-le-bourget-all.png

You can recognize the European climate shift around 1988 (apparent in most Central Europe temperature series), but since then it has been cooling (or at least not warming, I forgot to check the significance of that trend and don’t have my spreadsheet here right now) for 25 years! See this chart: http://espen.vestre.net/tmp/paris-le-bourget.png

26. BioBob says:

Thanks Willis. This seems so simple and cogent an argument that one wonders what Santer et. al. (12 authors ? really ?) really were after ? We can only wonder…

BTW, only \$32 to see the article – what a deal.

27. lee says:

Willis,
‘CONCLUSIONS:

• I many never’

I may never?

[Thanks, fixed. Perfect is good enough. -w.]

28. Questing Vole says:

If it took 3 and 5 years respectively for absorption rates to recover from the major eruptions of Pinatubo and El Chichon, why did it take so long after the relatively minor Mt Agung event?

29. Manfred says:

Hi Willis,

one thing was not mentioned. How can volcanoes be “the cause”, when (according to your figures) there has been no major eruption after Pinatubo ?

30. KNR says:

Well I take Solomon claims as a sign there is a god, for who else to arrange it so that volcanic eruptions could have so much influence to actually balance out the effect of AGW but only for the period when ‘the pause ‘ during other periods it could only have been ‘climate doom ‘ and volcanic eruptions play no role , along with the sun and lots of other elements which we often poorly understand.

31. Larry Brasfield says:
February 24, 2014 at 9:18 pm

I’m not arguing with what you say here, but maybe with something unsaid. The light which was not transmitted, accounted for as a transmission drop, has one of two other paths to take: (1) It can be reflected back to space; or (2) it can be absorbed.

A lot of volcanic debris is gray/black lava injected in the stratosphere, but only with huge eruptions like the Pinatubo. Most plumes don’t reach the stratosphere and are rained out within days/weeks. Most of the debris is heavy and drops out into the troposphere and surface within months.
Of interest is the SO2 which follows the plume. That remains in the stratosphere and is turned into SO3 (by ozone) which attracts a lot of water. That takes time, as there is very little water in the stratosphere, which also makes that it takes years before the drops are heavy enough to drop out of the stratosphere. It is these water drops which scatter sunlight in all directions, including partly back to space.

The main effect is not on temperature, but on CO2 uptake bij plants: the scattering makes that more leaves which are in the shadow of other leaves during part of the day then receive more scattered sunlight, which makes that the CO2 increase after the Pinatubo eruption was minimal, including any CO2 from the eruption itself…

32. Manfred says:

François says:
February 24, 2014 at 10:14 pm
I don’t understand your arithmetics, when you are trying to find .6 degrees missing when it really should be only .4. There is a reality, come to Paris and I will show you olive trees blooming there, that would never have occurred fifty years ago. What is your explanation? urban heat island effect?

—————————
Here is a link about UHI in Paris during heat waves. The increases in temperature a enormous
http://www.nasa.gov/pdf/505253main_dousset.pdf

Steve McIntyre has more data. 10 degrees for big cities and 5 degrees for smaller cities etc…
http://climateaudit.org/2010/12/15/new-light-on-uhi/

In Tokyo air conditioning alone increases temperatures by 2 degrees.

33. Christopher Hanley says:

Steyn smiles. He knows a lawyer to recommend …
—————-
Lordy, it won’t be long before suing Mann becomes a class action.

34. Richard Keen says:

Manfred says:
…How can volcanoes be “the cause”, when (according to your figures) there has been no major eruption after Pinatubo ?…
Great question!
Six years ago I made the case that the series of big volcanoes from 1963 to 1991 (Agung, el Chichon, and Pinatubo) threw enough stuff into the stratosphere to cool the earth by a few tenths of a degree, and that since 1995 the stratosphere has been clear. The punch line was that half of the warming over the past 40 years can be attributed to the this clearing – that volcanoes cooled the climate early on, and after Pinatubo was over and gone, the earth warmed back up. It was a good enough story that the New Scientist wrote it up:
http://www.newscientist.com/article/dn13376-lunar-eclipse-may-shed-light-on-climate-change.html?feedId=earth_rss20
I presented an update last year that showed the lack of volcanoes for the past 17 years actually contributed more to the overall warming than did CO2 and other greenhouse gases:
http://www.esrl.noaa.gov/gmd/annualconference/slides/69-130415-A.pdf
Of course, the New Scientist went for a second opinion, from none other than Susan Solomon. Solomon stated that volcanoes were adequately accounted for in the IPCC models and that volcanoes had no detectable (in the models) effect on the warming.
So now the same Susan Solomon claims the teeny volcanoes since 2000, all of which are less than a tenth the magnitude of the likes of Agung, el Chichon, and Pinatubo, can now outweigh the greenhouse effect. Meanwhile, those big guys way back then had no effect.
Curiously, the New Scientist has yet to call me for a second opinion on Solomon’s excuses for the “pause”.

35. M Courtney says:

This seems like a good basis for a retraction of the paper by Susan Solomon.

Which could become a little rolling snowball.

36. Agnostic says:

Willis,

This is a very interesting analysis. Very interesting indeed. A few questions:

– Playing devils advocate, I can imagine a (consensus/orthodox) response regarding the the Mauna Loa connection between reduced insolation after the eruptions and local temperatures along the lines of; the vulcanism has a global impact on temperature and not a regional one. The individual location is going to be affected by local conditions and may not necessarily respond to a localised reduction in sunshine in the way the overall climate system might. How might you counter that?

– Secondly, and related to the first, what is the location of the temperature station wrt the measurements for solar irradiance? Are they the same station? Obviously it’s Mauna Loa, but are the locations identical or is the temperature taken at a lower altitude? If so how would that effect the connection between temp and irradiance?

– I agree, no response at all in the temp record from what appears to be a really big reduction of insolation is really surprising. Are you saying there is virtually no lag in the response of the system to correct for it? If there is a lag, how long do you think? A few hours, days, months?

FWIW (probably not very much) I agree broadly with your “emergent phenomena” hypothesis. With a little bit left over for known unknowns, and unknown unknowns.

37. Scarface says:

The more reasons they find to explain the not happening CAGW, the more they admit their theory is wrong without saying so, meanwhile losing the scientific battle.

Never interrupt your enemy when he is making a mistake. Just watch and smile.

38. ralfellis says:

Manfred says: February 24, 2014 at 11:44 pm
One thing was not mentioned. How can volcanoes be “the cause”, when (according to your figures) there has been no major eruption after Pinatubo ?
___________________________________

+10

How can they “it was the volcanos” and keep a straight face, when there have been no significant volcanos??

Surely, this must be some kind of criminal offence. (Misuse of public funds in the US, I believe…)

SR

39. Something is fishy here Did Solomon have no idea of the Mauna Loa apparent transmission data? Then she would have know that it weren’t the volcanoes.

But what does it mean that this reference is the first listed on the NOAA site:

Solomon, S., J. S. Daniel, R. R. Neely III, J. P. Vernier, E. G. Dutton, and L. W. Thomason, 2011: The Persistently Variable “Background” Stratospheric Aerosol Layer and Global Climate Change. Science, Published online 21 July, Science Express, 2011,DOI:10.1126/science.1206027]

So what does that mean?
– Is it another Solomon or she has a very short memory?
– Willis is wrong somehow?
– Somebody does a lot of wishful thinking?
– honest mistake?
– noble cause corruption?

40. Michael Larkin says:

Willis, you say (in reference to fig 1):

“The El Chichón and Pinatubo eruptions reduced the downwelling solar energy by maxima of forty and thirty watts per square metre at Mauna Loa.”

I keep looking at fig.1, and I make it around 60 and 50 watts per square metre respectively. I may well be misinterpreting the graph, or maybe what you’re talking about doesn’t directly relate to the graph: I can’t claim to be a whizz kid when it comes to physics. Whatever, I’m puzzled about where your 40 and 30 figures come from. Could you please clarify?

41. Dr. Strangelove says:

Willis,
The 14 W/m^2 you measure at Mauna Loa is not comparable to the 3.7 W/m^2/K climate sensitivity. The units are different. The latter is per degrees kelvin change in surface temperature, and the forcing is at TOA (about 10,000 m altitude). Mauna Loa Observatory is at 3,400 m elevation.

The effect of Mt. Pinatubo eruption is global, not local in Hawaii, since the aerosols circulate in the stratosphere. And in fact global temperature did drop circa 1991.

42. LB says:

There is another experiment you can do. It’s to do with the lags in the atmosphere. How quickly do atmospheric temperatures change when the forcings are changed.

To do the experiment, you need to change the forcings. Now plenty of people say you can’t experiment with the climate, but its not the case.

Go out, measure the temperature at midday. Then we turn the forcing off, and see how quickly the temperature drops. You don’t have long to wait. About 12 hours will do it. The sun gets ‘turned off’ once a day, and you can see the change.

It turns out the change is very rapid. Diurnal temperature variations are large, highest for deserts, lowest for oceans, but rapid in all cases.

Hard to justify any long term lags to changes in forcings.

43. David L says:

You’re forgetting about all the volcanoes in the deep oceans that are erupting all the time without or knowledge. /sarc

44. Stephen Richards says:

This is why I get really annoyed with people like Roy Spencer who insist on saying that co² causes an increase in forcings (ooooh I hate those words) and therefore a rise in global temps.

Global temp as a parametre stinks and forcings as a concept in nonsense. BUT on question remains in my empty head all the time: How does an ice age form ? Milankovic possible but there are many if and buts around the predicted incoming energy change. So what else is there.?

• LB says:

This is why I get really annoyed with people like Roy Spencer who insist on saying that co² causes an increase in forcings

===========

My pet hate is that El Nino is an input into the system and not an output of the system

45. eyesonu says:

Willis, as always, very interesting. Thank you. Many/most of us appreciate your work. However, some fear it.

46. cynical1 says:

David L says:
February 25, 2014 at 1:29 am

You’re forgetting about all the volcanoes in the deep oceans that are erupting all the time without or knowledge. /sarc

NO NO NO.

We do know about them. They’re the ones making the bottom of the sea warmer.

That’s where the heat is hiding, but that naughty heat can’t fool us…

47. Kelvin Vaughan says:

Only yesterday Willis, I compared the CET with the big drops in transmissivity and found nothing obvious. I am strongly being converted to the argument that temperature is governed by pressure. How else can you explain that massive instantaneous swings in the amount of infrared coming down from the sky (clouds v clear sky) has very little effect on ground and air temperature.

48. David Wells says:

OK excellent work so why did we get ice ages then if everything is so in balance?

49. David Wells says:

Clearly sometimes everything is within a reasonable balance now but at times in the past everything has been reasonably out of balance but no one appears capable of determining exactly why sometimes there is balance and sometimes there is not. It does occur to me very often that all of these conversations are only possible because right now there is enough fuel, enough stability, enough technology and enough people to comment on the now and very carefully avoiding in specific instances the past like ice ages. This question has to be answered otherwise everything else is complete nonsense.

50. johnmarshall says:

Where on earth did you get that average 240W/m2 for insolation? The earth receives 1370w/m2 at TOA. Correct for albedo and adsorption and the total becomes 960W/m2 over the earth’s discal area. This translates as an average 480W/m2 over a hemisphere. Remember the day/night process. Total radiation is 240W/m2 FROM THE WHOLE PLANET. (two hemispheres).
The SB formulae gives a temperature of +33C for 480W/m2, reasonable given that te water cycle has to work. Your 240W/m2 gives -18C which means that the water cycle would NOT work.

Get Real.

51. Baa Humbug says:

This is an excellent post as usual.
I wonder if there are any data sets showing the atmospheric pressure around Mauna Loa for the same time period?
I’d suspect we would see high [er than normal] pressure at about the time of the eruptions and back to normal after 3 years (Pinatubo) and 5 years (El Chichon).

52. Watts Up With Your Maffs says:

“to warm two degrees by 2100, you have to warm at 0.2°C per decade”.
According to the NASA GISS, temperature anomaly in 1993 was +0.2°C, in 2013 was +0.6°C. That’s, um, 0.4°C in 20 years. Which is two decades.

53. Bill Illis says:

If a large stratospheric eruption has no temperature impact …

How can no volcanoes have a large temperature impact?

In climate science, this actually makes sense to them.

54. Pamela Gray says: February 24, 2014 at 9:32 pm

Thank you Willis for the interesting work and thank you Pamela for the great video animation.

55. Roy Spencer says:

I agree with much of this. The decrease in atmospheric transmission is mostly due to reflection, though, not absorption. One interesting aspect of the major eruptions is the increased greenhouse effect of the aerosol layer…there is a rather large warming in the lower stratosphere, as seen in the satellite LS (lower stratosphere) temperatures.

56. Cassanders says:

If we stick to a very simplistic (conseptual) model, Is not the figure 2b an interesting “indicator” of the “CO2-effect”? Would not night temperature be the most effective measure of the “insulating” properties of CO2? (Less signal to noise ratio) The simplyfying assumption then being that temperature have remained “unaffected” by eventual changes in water vapor, clouds, etc.
Incidentally (or perhaps not :-)) the night temperature increase os some 0.5 deg/ 30 years , which corresponds to some 1.5 deg by an extrapolation.

Cassanders
In Cod we trust

57. Mike Ozanne says:

Data again Mr Eschenbach, didn’t we talk about this before. There are some perfectly acceptable models over on aisle 6 in between the bent hockey sticks and the UK’s drier winters…..

58. Cassanders says:

…which corresponds to 1.5 deg. C per century by simple linear extrapolation.

Cassanders

59. Here are two links to animations provided by NOAA:

Personally, as a volcanologist, I’m not sure volcanoes can be held responsible for a “pause” in global warming. There have been too few large-scale eruptions in the past decades to make such a statement. Meantime, having observed the glaciers in Alaska during the last decade, I can say they are receding faster and faster. It’s just the same in the French Alps. Global warming is on the way. there might be some fluctuations here and there, but the global trend is worrying.
More on volcanoes on my bilingual blog:
http://volcans.blogs-de-voyage.fr

60. Reblogged this on gottadobetterthanthis and commented:
Willis provides direct observational evidenced that large volcano eruptions do not affect temperature in Hawaii despite the fact the decrease in solar energy there is obvious.

We live on a water planet. Seems obvious to me.

61. DHR says:

Your chart of Mona Loa temperature at noon and midnight shows that midnight temperature has increased at a rate of about 0.04C/yr although the words at the bottom state it has decreased at the same rate. A typo no doubt. But isn’t higher nighttime temperature but not daytime temperature one of the claimed hallmarks of AGW theory?

62. LT says:

El – Chichon exstinguished possibly one of the largest El-Nino’s and cooled the climate for years, and Pinatubo cooled the climate during a period of what should have been much warmer years. Redoubt was not enough to do anything, but it does not appear to have put enough SO2 into the stratosphere to show up on the stratospheric temperature satellite data. The climate aboslutely responded to millions of pounds of SO2 in the Stratosphere, through the 80’s and 90’s, I lived it.

63. thingadonta says:

The trouble with the IPCC’s ‘volcanos ate my warming’ excuse is that they don’t have a volcano at their house at the moment to eat it.

64. Joe Chang says:

but the Solomon paper was peer reviewed

65. Joe Chang says:

sorry, attempt to use font, peer reviewed

66. Gary says:

Willis, how much of the Mauna Loa temperature is under local influence and how much under the influence of the north Pacific ocean? Could it be that the vast oceanic heat sink is buffering the thermometer response to the insolation decrease?

67. Tom G(ologist) says:

If we look at the collective ejecta from all major eruptions since 2000 it does not add up to the volume ejected in the single 1991 eruption of Pinatubo. Assigning a generous estimate of the volume of each of the 19 recent major eruptions since 2000 there have been approximately 8 to 9 cubic kilometers of ejecta, whereas there were greater than 10 cubic kilometers ejected from Pinatubo in that single 1991 eruption.

Also, we just had a significant eruption two weeks ago of Mt Kelud, Indonesia. In fact, that single eruption has been the largest of the 21st century, so we should watch the temperatures to see if there is a difference. Although it is the largest in the 21st century, it is still an order of magnitude less than Pinatubo.

68. Rud Istvan says:

One quibble. The 2009 Eruption that caused the opacity blip was VEI4 Surychev in the Kurile Island, and not Redoubt. Otherwise, spot on. Santer and Solomon’s new paper is the third of its kind. Solomon had one in 2011, and Neely of CU wrote one in 2013 that got quite a lot of media hype.
Logic is simple. Models say pause says missing heat. It cannot be found anywhere in the oceans. So it isn’t there. IPCC says aerosols are the only Cooling radiative forcing. So it mustnbenin the aerosol fudge factors. Volcanoes spew aerosols. Voila. Except these wash out quickly unless they reach above the tropopause. Aging, Chichon, Pinatube, and Surychev did. As a counter example, Mt St Helen’s didn’t there have been 9 VEI 4 eruptions since 2000, and only Suyrchev temporarily affected atmospheric opacity and albedo. An essay from my draft next book.

69. Steve Keohane says:

Thanks Willis. Very interesting.

70. aaron says:

I would guess that surface pressure increases, winds slow, and, most importatly, evaporation would decrease, leading to less IR cooling.

• LB says:

I would guess that surface pressure increases, winds slow, and, most importatly, evaporation would decrease, leading to less IR cooling.

===========

Temperatures dropping mean increases in wind speed.

Look at the planets. The farther out you go, the higher the wind speeds.

On earth, look at the temperatures night and day, and wind speeds night and day. Night time wind speeds are higher, and less variable compared to the day. The reason is that during the day over land, thermals rise. These are columns of rising air. That acts like trunks of trees in a forest, and the wind has to weave its way through. The result is slower wind speeds, but more variability.

71. aaron says:

And cloud increase.

72. Resourceguy says:

I do hope someone is compiling the excuse list. I’ve lost track of all the random factor list and hiding places for heat.

73. thingadonta beat me to it. “The volcanoes ate my warming.” Except the volcanoes are invisible, and have no measurable effect on the transmission of sunlight. Are these climate scientists at Faber College? They must be Dean Wormer’s double-secret volcanoes. (RIP, Harold Ramis). Their only measurable property is the ability to excuse the absence of warming. How does this stuff get past peer review?

74. edcaryl says:
75. Jeff Alberts says:

GeologyJim says:
February 24, 2014 at 10:13 pm

Susan also blew the fluorocarbon-ozone thingy years ago. I think it’s pretty clear now that ozone over the poles is just a seasonal oscillation.

That’s been pretty clear since the mid-1950s.

76. Richard M says:

Stephen Richards says:
February 25, 2014 at 1:43 am
How does an ice age form ? Milankovic possible but there are many if and buts around the predicted incoming energy change. So what else is there.?

Albedo. When the solar input tilts a little more towards the SH (Milankovitch cycle) the sea ice around Antarctica becomes a larger source of albedo. As we’ve seen recently this sea ice can increase quite dramatically, most likely due to deep ocean currents. This starts to cool the Earth. This overall cooling allows more snow in the NH to last longer into the spring and summer creating even more albedo. The two forces positively enforce each other until the NH snow is maintained all summer long and the glaciers start to form.

77. kb says:

Willis, you’ve said repeatedly, “the emergent phenomena of the climate system respond instantly (hours or days, not months or years) to any change in the temperature. If it cools, we rapidly get a drop in albedo, which allows in more sun, and the balance is restored. If it warms, very soon thereafter albedo increases, we get less sun, and again the balance is restored.”

I agree there appear to be significant negative feedback systems working to prevent runaway effects. However, this seems to imply that we would never get a significant temperature change. However, we know that there have been well-documented warmer and cooler periods even just since the little ice age.

How do you account for these changes given the negative feedbacks?

kb

78. rgbatduke says:

On the one hand, (1st order, linear) correlation is not causality. On the other hand, lack of correlation makes causality even less likely — to continue to argue for causality one has to postulate a far more complex, multivariate system rather than a simple linear response hypothesis. And the trouble with that sort of hypothesis — which I firmly endorse — is that it shuts down all the simple, trivial, bullshit arguments — deconstructing a complex, nonlinear, strongly coupled dynamical system on the basis of some combination of model(s) and observation is not a job for the faint of heart, and it is one where one can only gain insight after understanding at least the principle non-linear features of the system dynamics.

One of my favorite examples from my unholy past is solving predator-prey (Lotka-Volterra) or epidemiological equations. These are systems of coupled differential equations that describe in the crudest of terms population dynamics of two coupled populations, one of prey (say, rabbits) and the other of a predator (say, foxes) that relies strictly on the rabbits as a food source. In the simples forms, the rabbits are presumed to live in a more or less unboundedly good environment and have no other source of demise. Rabbits breed more rabbits at a rate proportional to the number of rabbits, which in the absence of foxes would lead to an exponential explosion in the number of rabbits. However, foxes eat rabbits at a rate proportional to the probability of a meeting (yes, every time a fox and rabbit meet the fox eats a rabbit, it’s an oversimplified model) which decreases the number of rabbits.

Foxes, on the other hand, die off in the absence of rabbits. They do reproduce at a rate proportional to the number of foxes times the number of rabbits, but if the number of rabbits gets too small foxes starve to death faster than they reproduce no matter how many foxes there are. Put these together, and one gets a very simple linear model:

$\frac{dR}{dt} = \alpha R - \beta RF$
$\frac{dF}{dt} = \delta RF - \gamma F$

The constants $\alpha,\beta,\gamma,\delta$ are rate parameters, related to probabilities of encounter. One can look at:

http://en.wikipedia.org/wiki/Lotka%E2%80%93Volterra_equation

if this sort of thing interests you. In particular look at the complexity of the solutions $R(t),F(t)$ from any given initial condition and set of parameters. The numbers of foxes and rabbits form a cycle — for almost all possible numbers of foxes and rabbits the population is disequilibrated relative to a fixed point where “equilibrium” occurs. Rabbits increase. Eventually foxes respond to this increase, and increase as well. As there are more and more foxes and rabbits, eventually well-fed, rapidly reproducing foxes overtake the rabbits and the rabbit population starts to decrease. Eventually one has a large population of foxes all slowly starving, a small number of rabbits that are finally rare enough that they can hide from the foxes, and the foxes die off to where the small rabbit population can once again start to soar in a nearly fox-free environment.

The stable points of the cycles are called attractors, and there is an entire literature dedicated to attractors, strange attractors, and limit cycles that can be periodic/poincare or chaotic. This simple model gets very complex indeed with tiny changes — making the interactions nonlinear, introducing a second predator or second prey animal, adding terms to represent plant life and the possibility of rabbits consuming all of their food source with or without fox predation, adding diseases that kill off rabbits very rapidly from epidemics once the rabbit population crosses critical thresholds where the probability of transmission of e.g. Tularaemia crosses a critical threshold where every infected rabbit infects on average more than one other rabbit. I’ve actually written discretized Monte Carlo code to simulate epidemiological models (for venereal disease) for fun for my wife and a fairly well known epidemiologist back when she was an infectious disease fellow, and was told that the results of the computations had some influence on their thinking (although I don’t know that I got as much as an acknowledgement in a paper, sigh).

Now imagine trying to model an entire ecology. Or (since similar models are used in economics) the market. Or yeah, the climate.

The problem is this. In a linear model, one can do things like solve for the stable points — the attractors — in some high-dimensional space, and one can even talk sensibly about limit cycles or at the very least comparatively bounded cyclic behavior of the system as it traverses curves in phase space bound to attractors. That’s because terms like $\alpha$ and $\beta$ are constants in time — they are fixed and the model evolves deterministically and if it is indeed linear, often computably.

In a nonlinear model, all bets are off. In a model that is both nonlinear and has non-stationary values of the coupling constants, the moral equivalent of $\alpha(t), \beta(t)$ where there can be both systematic variation (think of the way TSI varies due to the simple shape of planetary orbit) and stochastic variation (where we cannot predict the microstate of the sun from hour to hour or day to day and in any event it follows no “nice” curve — it is at best modelled by a random process with certain properties even though it is hardly random). Think albedo — changing from hour to hour, but in a generally bounded way, but where it is not clear if albedo is stationary on a decadal timescale, if it depends in critical ways on things like solar state or aerosol content or soot content of the atmosphere, all of which themselves are varying.

In this case the attractors themselves in any semi-linearized dynamical model are wandering all over the place. In a truly nonlinear model, the system often has multiple (strange) attractors, attractors in fractal distributions, and they are constantly moving, causing the entire topology of the quasi-cyclic evolution to change on the same time scale as the motion itself.

As Willis says, the really amazing thing is that the climate is remarkably stable in the short run to perturbations, stubbornly staying locked within a comparatively small temperature range where planetary life is abundant. Except, of course, when it doesn’t and we plunge into glacial eras lasting 90,000 years where ice kilometers thick builds up on close to 1/4 of the Earth’s surface near the poles and up high in the mountains.

It is partly because this sort of instability — or global multistability, with entirely distinct characters of strange attractor families appearing in the empirical record — that I think it is, on the whole, wiser not to kick the climate in the balls when we have no idea where it will end up. Increasing CO_2 in a strongly coupled nonlinear system could just as easily trigger the next ice age as cause thermageddon from heat.

You don’t believe me? Take a gander at the predator prey problem. When the numbers stay near the attractor, life is good for foxes and rabbits. Few rabbits starve, few foxes starve, fox/rabbit numbers stay close to some sort of “optimal” number for the presumed problem ecology. Bump either the number of foxes or the number of rabbits and all you do is kick the system into a large limit cycle, one that in time will carry both foxes and rabbits closer to extinction. Exactly the same thing will happen if one “suddenly bumps” e.g. $\alpha(t)$ or the other parameters, makes the attractor jump farther away from the existing population values. If you simply add a certain amount of dynamic stochastic noise to the parameters, basically “shake up” the attractor so it does a random walk (constrained or unconstrained) since there are no dissipative terms in the coupled ODEs that cause the system to stabilize and relax to a bounded orbital range, it is quite likely that the system will get “shaken” into less and less stable orbits, increasing the probability of catastrophe.

We could all argue about how likely this sort of catastrophe is for the real climate, but the fact of the matter is that we have no idea, and our models don’t come close to being able to explain the observed climate variability. If you like, the cyclic structure, stability, fluctuation/dissipation, time constants, attractor(s) of the GCMs do not exist in good correspondence with the actual climate. We don’t really know what the climate would be doing without a systematic hand twisting up the CO_2 knob (and doing crazy, mad things with all of the other knobs in the system even as the system is thrashing its enormous way through multiple interacting decadal cycles around attractors we are completely incapable of describing or incorporating consistently into a dynamic model). It could, paradoxically enough, be stabilizing the system — pulling it tighter to the family of currently stable strange attractors, reducing the excursion of the attractors. It could be squeezing the system — altering the geometry of the cyclic motion, constraining the attractor excursions to a changing/flattening hyperellipsoidal volume. What it probably isn’t doing is nothing, and what we can’t do is predict how the system will respond on a decadal time scale, any more than we can for foxes and rabbits as an approximation for an actual ecology.

All things being equal, the human species needs to gradually wean itself from carbon-based fossil fuels, both because CO_2 has a mostly unknown (but almost certainly nonzero) effect on the climate that could be good, could be bad, could be first good and then bad, could be almost anything, and because fossil fuels are a precious resource far more valuable as the basis of chemistry or smelting or making concrete than they are for burning. We are burning a long term planetary resource at a prodigious rate. Ultimately, human civilization will need to be based on energy resources that are substantially less limited by scarcity, resources that might last through the next glacial era in the current ice age, or humans will experience their own “mass extinction event”.

In the meantime, because we really do not know what the climate is doing or will do in the future, but we have the immediate need to keep people from starving or living in energy poverty, the sensible thing to do is wait, watch, burn carbon as needed but invest fairly heavily in non-carbon-based energy for the long term. Fission (Uranium and Thorium), solar (sorry, I know a lot of you think solar is some sort of devil but I just think it is a devil that is already making borderline economic sense to the point where I’m contemplating putting solar on my own roof and am doing a ROI analysis to see what the amortized payback time is) and ultimately, we can profoundly hope, fusion as if we ever perfect D-D fusion the human species will make the transition to stability — we will never run out of energy in less than geological time (millions of years, if then). The human species will evolve or go extinct long before we even measurably reduce the amount of deuterium in the oceans.

rgb

79. aaron says:

I’m also wonder, how much do the aerosols above clouds diminish the cooling effect of clouds? Is it significant enough that cloulds could become net warming and the increased cloud cover help prevent cooling instead of cause it?

80. JP says:

The problem with Dr Solomon’s theory is that we haven’t had any erruptions during the last 15 years that have come close to Mt Pinatubo or El Chicon.

81. Jay says:

Bill Illis says:
February 25, 2014 at 3:40 am
If a large stratospheric eruption has no temperature impact …
How can no volcanoes have a large temperature impact?
In climate science, this actually makes sense to them.

This reminds me of the old Jean Paul Sartre joke.

The existentialist sits in a Paris Cafe, and orders…”Madame, I would like coffee with no cream”
The waitress comes back, monsieur Sartre, we are out of cream, would coffee without milk be acceptable to you?

82. JP Miller says:

RGBatDuke,

Your expertise and eloquence are undeniable. However, your conclusion (or hypothesis) based on analogy that, “What it [CO2] probably isn’t doing is nothing…” is without merit based on your argument (if “probably” means better than 50/ 50 odds, and “nothing” means in relevance to CAGW). The issue of CO2-driven CAGW is one of physics, not of what, generic, non-linear choatic, multi-process systems do or might do. And, as for the physics effects of CO2 on global temps/ climate, well, as you indicate, we have no idea. However, given the amazing stability of the temp/ climate system would it not seem unlikely to be knocked out of that stability by anything but rather large changes in energy input, such as implied by Milankovitch cycles?

Is it not likely the huge H2O heat sink we have, the physics of the hydrological cycle, along with the inherent dynamics of a gaseous envelope overwhelm almost everything except those rather large changes in energy input?

I also question your point about limited coal/ oil/ gas resources. Assuming markets are allowed to work such that price reflects scarcity, the odds are high, based on the geology of exploitation, that scarcity will not emerge suddenly in the course of a few decades, but rather gradually such that price will cause alternative energy sources to be brought into the market to replace increasingly-expensive fossil fuels. (Big assumption here: that governments are not uniformly intransigent to economic reality…. they can be sometimes, of course, but usually only for a few decades; e.g., Soviet Union and China).

Finally, are you taking into account the huge subsidies that factor into your cost of solar panels? While I can understand you taking advantage of those subsidies for purely personal economic reasons, I cannot abide that example as part of an argument for solar becoming economic. In addition, and sadly, energy prices are probably higher today than they might be if the US government were CO2-neutral on what sources of energy could be exploited.

I appreciate your incisive arguments that debunk simplistic climate science, but I wonder if you haven’t done a little too much hand-waving in this latest piece.

83. MikeN says:

Does the paper actually claim the volcanoes did it? The press reports I’ve seen all seem to say only that ‘volcanoes cause cooling.’ There is no detail where they actually argue that there is more volcanoes now than before. It would be like if I said StefanBoltzman says warmer objects emit more heat into space, and argued that that is the reason for the pause.

84. aaron says:

Ok, think of this dynamic. Less SW reaches the clouds, however, the SW that does is more likely to be absorbed because it is reflected back down by the aerosol in both the SW, and LW by the stratospheric GHE Dr. Spencer mentioned. So there’s less heat at the near surface and more between the cloud layer and stratospheric greenhouse (do satellites see higher surface temps than surface stations?).

Now, all over the world, there’s less SW reaching bodies of water and moist surfaces. I’d like to know more about the water vapor feedback research in the IPCC report and models. I recall much of it was considered confirmed by volcano effect analysis. I bet they account for temperature, maybe wind, but not the direct effect of SW radiation.

85. Kristian says:

Willis, like Bob Tisdale has pointed out to you on many occasions, the global temperature rise in 1982/83 is clearly caused by the massive El Niño that year. Yet, there’s a very stunted global response. And the significant global temperature drop between 1992 and 1995 came during a period of mostly positive to distinctly positive ENSO-conditions. It goes the opposite way of what one could expect.

It is very clear from this that both the El Chichón and (especially) the Pinatubo eruptions had a major impact on global temperatures. Of course, they would not have a major impact (or not necessarily a noticable impact at all) on regional or local temperatures (like Mauna Loa). Because here, normal variations are too large and … regional/local. The volcanic influence is small compared to for instance cloud cover and year-to-year variations in regional/local weather because of position of pressure systems, winds, rains and so forth, but it is an influence that works globally. So the further you zoom out, the clearer the volcanic signal will stand out.

86. Joe Born says:

rgbatduke: “Put these together, and one gets a very simple linear model:”

A nomenclature question, if I may, regarding the term “linear.” I had thought I understood from people who seemed to know this stuff that equations such as those you set forth above are considered nonlinear, i.e., that, because of the RF term, the fact that [R_1(t), F_1(t)] and [R_2(t), F_2(t)] individually are solutions would not necessarily imply that [R_1(t), F_1(t)] + [R_2(t), F_2(t)] is.

Could I impose upon you to explain the meaning of “linear” in this context and what the implications of that feature are?

87. aaron says:

LB, it depends on distribution of the effect. There should be bigger temp drops in mid to low latitudes, decreasing temp and pressure differentials with the north.

88. Willis Eschenbach says:

Agnostic says:
February 25, 2014 at 12:36 am

Willis,

This is a very interesting analysis. Very interesting indeed. A few questions:

– Playing devils advocate, I can imagine a (consensus/orthodox) response regarding the the Mauna Loa connection between reduced insolation after the eruptions and local temperatures along the lines of; the vulcanism has a global impact on temperature and not a regional one. The individual location is going to be affected by local conditions and may not necessarily respond to a localised reduction in sunshine in the way the overall climate system might. How might you counter that?

The reduction in incoming sunlight from e.g. El Chichon was global in nature. The signs of it were picked up all over the world. So we can assume that over the entire Pacific there was a very large drop in incoming sunlight, not just at Mauna Loa. As a result, we should have seen widespread cooling, including at Mauna Loa … but we saw none, either at Mauna Loa or in the UAH MSU satellite records for the northern hemisphere lower tropical temperatures.

– Secondly, and related to the first, what is the location of the temperature station wrt the measurements for solar irradiance? Are they the same station? Obviously it’s Mauna Loa, but are the locations identical or is the temperature taken at a lower altitude? If so how would that effect the connection between temp and irradiance?

They are both measured at MLO, the Mauna Loa Observatory. That’s one reason that it’s such a good natural experiment.

– I agree, no response at all in the temp record from what appears to be a really big reduction of insolation is really surprising. Are you saying there is virtually no lag in the response of the system to correct for it? If there is a lag, how long do you think? A few hours, days, months?

FWIW (probably not very much) I agree broadly with your “emergent phenomena” hypothesis. With a little bit left over for known unknowns, and unknown unknowns.

Actually, what I said above was that the lack of temperature response was not surprising, at least not to me. The major compensatory mechanism of the planet, the thunderstorms, are fast-acting and very powerful. They, and the other emergent phenomena, only emerge based on the actual present conditions. So when the temperature rises between dawn and noon, as soon as the threshold is passed the cumulus appears. And as a result, there is little lag in the response.

w.

89. Willis Eschenbach says:

Michael Larkin says:
February 25, 2014 at 12:59 am

Willis, you say (in reference to fig 1):

“The El Chichón and Pinatubo eruptions reduced the downwelling solar energy by maxima of forty and thirty watts per square metre at Mauna Loa.”

I keep looking at fig.1, and I make it around 60 and 50 watts per square metre respectively. I may well be misinterpreting the graph, or maybe what you’re talking about doesn’t directly relate to the graph: I can’t claim to be a whizz kid when it comes to physics. Whatever, I’m puzzled about where your 40 and 30 figures come from. Could you please clarify?

Michael, good question. The key is that in general the atmosphere absorbs about 20 W/m2 of solar energy at MLO. So the eruptions reduced the energy by 40 and 30 W/m2 … when you include the twenty W/m2 you get your figures of 60 and 50, but that’s the total absorption, not the reduction caused by the volcanoes.

w.

90. Don J. Easterbrook says:

Well done (as usual) Willis. You’ve quantified what I’ve been saying qualitatively for decades–(1) volcanic eruptions are too short-lived to affect climate over long periods of times, (2) volcanic eruptions are sporadic, not cyclical like climate, (3) there is no known correlation between volcanic activity and climate over long periods of time, and (4) a volcanic cause of global warming is thus not plausible.

91. Pamela Gray says:

Now it WOULD be interesting to see data from the African deserts over time. Since it is always “blowing in the wind” and African periods of rain and periods of drought correspond to weather pattern variations, I surmise that sometimes there is a lot and sometimes there is less of this dust. At the very least, this dust is ubiquitously present to one degree or another in a very important part of the globe.

92. Willis Eschenbach says:

johnmarshall says:
February 25, 2014 at 2:45 am

Where on earth did you get that average 240W/m2 for insolation? The earth receives 1370w/m2 at TOA. Correct for albedo and adsorption and the total becomes 960W/m2 over the earth’s discal area. This translates as an average 480W/m2 over a hemisphere. Remember the day/night process. Total radiation is 240W/m2 FROM THE WHOLE PLANET. (two hemispheres).
The SB formulae gives a temperature of +33C for 480W/m2, reasonable given that te water cycle has to work. Your 240W/m2 gives -18C which means that the water cycle would NOT work.

Get Real.

Egads, sire, such passion! “Get Real” indeed … let’s do just that. Here’s the reality.

We start with the TOA solar irradiation, which is about 1360 W/m2. It is intercepted by the disk of the earth, with a cross-sectional area intercepting the sunlight of pi * r2 square metres, where r is the earth’s radius. So the total energy intercepted by the earth is 1360 pi r2 watts. Note that the square metres cancelled, so this is the total insolation in watts.

Now, how much does that average out to per square metre of planetary surface area? To get that, we divide the total intercepted energy in watts (1360 pi r2) by the total surface area in square metres, to give us watts per square metre. The surface area of the planet is 4 pi r2. As you can see, this calculation gives us

1360 pi r2 / 4 pi r2 = 1360/4 ≈ 340 W/m2 average solar radiation.

Now, as you point out, about 100 W/m2 of the incoming solar energy is reflected back to space, leaving us with the 240 W/m2 as the figure I used for the average insolation after albedo.

Finally, you are correct that the SB formula gives ~ -18°C as the blackbody equivalent of the radiation of 240 W/m2 … and since the planet is not frozen, we note that the poorly-named “greenhouse effect” is alive and well, and keeping us from freezing.

w.

93. Willis Eschenbach says:

Watts Up With Your Maffs says:
February 25, 2014 at 3:28 am

“to warm two degrees by 2100, you have to warm at 0.2°C per decade”.
According to the NASA GISS, temperature anomaly in 1993 was +0.2°C, in 2013 was +0.6°C. That’s, um, 0.4°C in 20 years. Which is two decades.

Well, um, no. You don’t just take the starting and ending temperature to determine the trend. You need to actually calculate the trend. Grab a “maffs” textbook, the maths aren’t too hard, or get Excel to do the heavy lifting for you.

For the 20-year period from Jan 1994 to Dec 2013, the GISS LOTI trend was 0.09°C per decade. This is so small that it is not statistically significant (p = 0.09). In addition, it covers a deeper reality, which is that the trend for the entire 21st century to date is 0.02°C per decade. So my point stands. By now, given the DEATH BY TWO DEGREES WARMING BY 2100 claims, we should have seen a lot of warming.

We haven’t, and that’s what Solomon et al. are scrambling to explain.

w.

PS—Please take this in the right way, but your screen name is pathetic. It makes you look like an illiterate loser wannabe. I’d change it if I were you … just saying, if you want to get traction, the name’s not helping.

94. Jim G says:

Willis says:
“• My oft-repeated claims about the lack of effect of volcanoes on the global temperature are completely borne out by these results.”

When land based volcanic activity occurs on the 30% of the Earth’s surface which is not covered by oceans, one could hypothisize that undersea eruptions are adding heat to the oceans at the same time in that 70% of the planet for which data is limited to non-existent. Too bad our data on these eruptions is so limited. The late Iben Browning believed that volcanism worldwide was cyclical and inter-related. If so, then, at times, when we see high land based activity there may be even more undersea activity in that 70% that we do not see, thereby increasing temperature on a global basis by warming the oceans. In any event, that undersea volcanic activity is a variable to be considered along with the time lag for that heat to reach the surface and/or effect the oceanic oscillations. Perhaps as part of your theorized planetary self regulation or one of the causal variables which now and again significantly disrupt that regualtion.

95. BobG says:

rgbatduke, a very enjoyable post about something I know just a little from a course I took many years ago. There are three conclusions that you came to that I don’t agree with. The first conclusion is really more of an implication from what you wrote – essentially that we can control our CO2 output. This is essentially false at our current technological and social development level. Population is growing fast and the desire to live prosperous lives is not changing. Therefore, more energy is needed and will be used. Hydrocarbons and coal will be burned until a less expensive alternative is developed. You wrote that we would need the hydrocarbons in the future. There will always be hydrocarbons available. The issue is expense. Most hydrocarbons are locked in shale or rock that is very impermeable. Better technology, more oil and gas we get from those rocks (example the shale boom in North America). The race is not to stop using hydrocarbons, the race is to advance our technology such that we become more efficient and develop other inexpensive energy alternatives to hydrocarbons. If we don’t, civilization will gradually crash as we run out of inexpensive energy- with the hydrocarbon and coal mining extraction continuing apace.

Your idea that CO2 is likely to cause some change is likely true. However, your conclusions are not. CO2 has varied in the geological past with periods of time where CO2 was much higher than now and periods when it is not. Yet life flourished on the earth during those periods of time. The earth temperatures were very stable during those periods except during periods of time when the earth experienced ice ages. But even in ice ages, the ice stopped advancing at some point and the earth reached another fairly stable period. Given, we know that temperature and conditions remain very stable even though there are events that occur such as volcanoes and even super volcanoes and other calamities that in the geological record are very brief as temperatures and conditions return to a stable value very quickly. From the geological record, it seems very unlikely that changes in CO2 are capable of having a huge impact on temperature. This implies robust negative feedback mechanisms that bring the earth back to a relative equilibrium. Finally, geology and and life over the last 500 million years, has gradually sequestered more and more CO2 into sediment. This has caused the gradual decline of CO2 in our atmosphere. The decline is forcing evolutionary changes in life such as the development of plants that are able to concentrate CO2. Most food plants are such but most plants on earth are not. Eventually, if trends continue, CO2 levels will get low enough that most current life will become extinct and something else takes over while life can flourish on planet earth. Our stay on earth will increase the levels of CO2 “dramatically” for only a brief time geologically speaking – but from the point of view of current life on earth that flourishes in the present of CO2, this increase is a very good thing.

96. Willis Eschenbach says:

Roy Spencer says:
February 25, 2014 at 3:58 am

I agree with much of this. The decrease in atmospheric transmission is mostly due to reflection, though, not absorption.

Dr. Roy, do you have a source for that statement? I ask because the only record that I have of albedo around the time of Pinatubo, the Hatzianastassiou dataset, looks like this:

As you can see, hemispheric albedo dropped immediately following the eruption. I ascribe this, of course, to the delayed daily formation of cumulus and cumulonimbus when there are reduced tropical temperatures …

One interesting aspect of the major eruptions is the increased greenhouse effect of the aerosol layer…there is a rather large warming in the lower stratosphere, as seen in the satellite LS (lower stratosphere) temperatures.

I’ve always ascribed the majority of that stratospheric warming to the increased absorption of sunlight. Even the brightest and most reflective of aerosols absorb some sunlight, and the dark aerosols, particularly black carbon, absorb a majority of the incident sunlight.

It’s an interesting question, however, and one which I haven’t considered, as to which would warm it more, SW or LW absorption.

All the best to you, and as always, thanks for all the good word you’ve done. As you can see in the figures, I use the fruits of your labors in my research all the time.

w.

97. Les Johnson says:

Willis: Where did you get your figure for 287 watts/m3 at the equator? Doveryai, no proveryai.

For what its worth, I get similar numbers when I calculate it out.

As another commenter had posted, have you seen this? Very similar work to yours, and one chart in particular is identical to your Fig 4 and 5.

http://notrickszone.com/2013/12/22/disappearing-excuses-aerosols-likely-not-behind-the-warming-pause/

I also agree with your comments about Mosher. He comes across as bit too smug. He needs, IMHO, to expand his rather cryptic comments. Perhaps he is smarter than the rest of us, but unless he explains it better, he does not actually prove he is the brightest crayon in the pack.

Good work. I always enjoy your postings.

98. Michael Larkin says:

Thanks very much for your answer, Willis. Much appreciated.

99. Aphan says:

First, all volcanoes erupt differently and eject different things because the molten rock inside them is made of different minerals and differing amounts of gases also exist in every volcano. To study only a certain type of eruption-and the amount of particulates and gases they eject and assume that all other volcanic activity is the same is an unscientific and false assumption.

Some kinds of volcanoes erupt violently and suddenly and eject clouds of heat and gas and ash into the air for miles. Some volcanoes erupt sluggishly with a less explosive start and more magma crawl than particulate matter. And every range in between. Some volcanoes simply vent gas constantly into the air so their magma chambers either never erupt (no pressure build up) or take a very long time or experience sudden changes that cause a rapid buildup beyond their ability to vent and they erupt.

I’m currently (as in right now) watching a science show featuring the volcanic activity in Iceland. The vulcanologist just said that the volcanic eruption in 2010 that grounded all of the airplanes for days created a special kind of ASH that was powdery thin and remained airborne for a long time-thus threatening the airplane engines. That ash is caused when an older magma chamber has built up an “enriched gas content” over the years and ICE or WATER is suddenly introduced into the chamber. That ice/steam expansion causes the magma to explode into very tiny, dust like particles as it explodes, and drives those particles HIGH into the atmosphere along with it’s gases.
But other volcanic explosions on the same continent have produced larger, round pebble like matter that doesn’t stay in the air at all.

SO-as I’m watching, they start talking about a volcanic eruption in 1783 of an Icelandic volcano called Laki. Laki literally rained FIRE and ash and magma on it’s location for 8 months. It caused famines and droughts and lowered the temperature of the entire planet. It’s effects are estimated to have killed over 6 MILLION people globally, making it the deadliest eruption in historical times. It is suspected to be the cause of one of the coldest periods during the Little Ice Age.

From wiki-
“On June 8 1783, a fissure with 130 craters opened with phreatomagmatic explosions because of the groundwater interacting with the rising basalt magma. Over a few days the eruptions became less explosive, Strombolian, and later Hawaiian in character, with high rates of lava effusion. This event is rated as 6 on the Volcanic Explosivity Index, but the eight-month emission of sulfuric aerosols resulted in one of the most important climatic and socially repercussive events of the last millennium.”

So having said the above, here’s my point for Willis-it wasn’t so much the fine ash/rock particulates in the air, or the magma, or the cooler earth that affected the climate so much-it was 8 months of outgassing of toxic sulfuric aerosols-which became sulfuric acid rain, and caused sulfuric acid rivers and water, and covered entire countries in sulfuric dust.

So what of ALL the volcanoes, both known and unknown, that don’t “erupt” particulates into the air, or cause ash clouds that block the sun…but literally spew GASES-CO2, Sulfur, methane etc into our atmosphere 24/7. They won’t show up on the atmospheric records as “eruptions”, they don’t get any attention, they aren’t recorded or talked about. What about the submarine volcanoes, they suspect thousands of them, that are either venting OR actually erupting on the ocean floor 24/7 (thermal vents spew HOT water into cold oceans 24 hours a day, for decades that is more than 300 degrees) that no one has profiled or accounted for or measured? Where does all of THAT gas go? The heat? If a handful of land eruptions occurring on 30% of our planet (the surface) can affect our atmosphere, what can both large and small eruptions occurring in greater number, for longer periods of time, on 70% of our planet (the ocean floor) do to it?

When we talk about the energy budget, why does not one study take into account the ENORMOUS amount of energy it takes to move JUST the Icelandic and American tectonic plates away from each other at just the surface a measurable rate of an inch per year, not to mention all the other movement going on, on the ocean floor? Where is that energy coming from? Why isn’t the geothermal energy coming FROM this planet accounted for, and if it is, how do we know the measurement of it is even accurate? How accurately are we “estimating” the energy that is generated on this planet as compared to the energy that “leaves” it?

100. Tim Clark says:

[ Ferdinand Engelbeen says:
February 24, 2014 at 11:48 pm ]

I can accept as a theory that less light results in less photosynthesis (although light is very, very rarely the most limiting factor), but I’m having serious issues with your alledged light scattering in the stratosphere reducing incident radiation on understory leaves. Was that /sarc/ or a joke?

101. dscott says:

The El Chichón and Pinatubo eruptions reduced the downwelling solar energy by maxima of forty and thirty watts per square metre at Mauna Loa. Yes, however your chart clearly shows a significant drop in Mauna Loa Temp Anomaly during the following time periods which is similar what happened to the GLOBAL Temp Anomaly. I drop in temp, is a drop in temp no matter how you parse it.

Your conclusion is faulty in that you too broadly applied a regional temperature record of Mauna Loa (a single climate system) to the GAT which is composed of a wide variety of land and sea climate systems, so what you really proved is the homogenizing and buffering effect of the surrounding Pacific Ocean around the Island of Hawaii that smooths out temperature changes. Whereas, if you look at the SH you see no increase in average temp but in the NH you do see an increase from 1980 to 1998. Global Warming isn’t global if it isn’t happening elsewhere on the planet, but by the same token, both SH and NH average temps recorded a DROP after volcanic events.

102. timetochooseagain says:

There is little doubt that Solomon et al is a bad paper. And there is little doubt that the effect of volcanoes is widely exaggerated.

That said, as “proof” that volcanoes have no effect at all this article utterly fails.

And to be clear, that is what it purports to be:

“I have persisted in saying that volcanoes basically don’t do jack in the way of affecting the global temperature. I can finally demonstrate that unequivocally because I’ve stumbled across a very well-documented and precisely measured natural experiment.”

Well, no. For several reasons.

To begin with, one cannot demonstrate anything about global temperature by using a dataset of local temperature. On needs something more like a closed system so that one can actually deal with the temperature characteristic of it and the heat flow in and out. So the temperature data for Mauna Loa itself are utterly irrelevant.

Of course, you also purport to demonstrate this finding scales up to the global scale using satellite data and the “eyeball method.” You claim you don’t see the effect. But an inability to see the effect, is not a demonstration that an effect does not exist.

What you could have done, instead, is something that I actually did do: try to isolate an effect if it exists.

If you would like me to explain to you what I did, I can. I walk through the steps in the post itself but it may be difficult to follow. I note that I find there is an effect from volcanoes, contrary to Willis arguing one does not exist at all.

I also note that I find the effect of volcanoes is small, unlike other analysts more inclined toward the other end of the spectrum. Even the largest volcanic eruptions since 1850 have not resulted in peak cooling of global surface temps of even a quarter of a degree.

103. Willis Eschenbach says:

Claude Grandpey says:
February 25, 2014 at 4:59 am

… Meantime, having observed the glaciers in Alaska during the last decade, I can say they are receding faster and faster. It’s just the same in the French Alps. Global warming is on the way. there might be some fluctuations here and there, but the global trend is worrying.

Thanks, Claude. However, I fear your information is a bit out of date. In fact, since the switch in the PDO, Alaska has been cooling, not warming. See e.g. The First Decade of the New Century: A Cooling Trend for Most of Alaska, where the abstract says:

Abstract: During the first decade of the 21st century most of Alaska experienced a cooling shift, modifying the long-term warming trend, which has been about twice the global change up to this time. All of Alaska cooled with the exception of Northern Regions. This trend was caused by a change in sign of the Pacific Decadal Oscillation (PDO), which became dominantly negative, weakening the Aleutian Low.

This weakening results in less relatively warm air being advected from the Northern Pacific. This transport is especially important in winter when the solar radiation is weak. It is during this period that the strongest cooling was observed. In addition, the cooling was especially pronounced in Western Alaska, closest to the area of the center of the Aleutian Low.

The changes seen in the reanalyzed data were confirmed from surface observations, both in the decrease of the North-South atmospheric pressure gradient, as well as the decrease in the mean wind speeds for stations located in the Bering Sea area.

Regards,

w.

104. Willis Eschenbach says:

LT says:
February 25, 2014 at 5:23 am

El – Chichon exstinguished possibly one of the largest El-Nino’s and cooled the climate for years,

Dear heavens, protect me from the blind … the earth WARMED after El Chichon. Look at Figures 4 & 5 … the clue is, when the blue line goes up it means warming.

w.

105. Willis Eschenbach says:

Tom G(ologist) says:
February 25, 2014 at 6:18 am

If we look at the collective ejecta from all major eruptions since 2000 it does not add up to the volume ejected in the single 1991 eruption of Pinatubo. Assigning a generous estimate of the volume of each of the 19 recent major eruptions since 2000 there have been approximately 8 to 9 cubic kilometers of ejecta, whereas there were greater than 10 cubic kilometers ejected from Pinatubo in that single 1991 eruption.

Thanks, Tom. And despite that, at Mauna Loa the reduction in sunshine from El Chichon was greater than from Pinatubo … which proves, if anything, that reduction in sunshine is NOT solely a function of the volume ejected.

w.

106. Baa Humbug says:
February 25, 2014 at 2:53 am
This is an excellent post as usual.
I wonder if there are any data sets showing the atmospheric pressure around Mauna Loa for the same time period?
I’d suspect we would see high [er than normal] pressure at about the time of the eruptions and back to normal after 3 years (Pinatubo) and 5 years (El Chichon).

Good point – this would be very interesting too compare, do you agree Willis?

107. Willis Eschenbach says:

kb says:
February 25, 2014 at 7:39 am

Willis, you’ve said repeatedly, “the emergent phenomena of the climate system respond instantly (hours or days, not months or years) to any change in the temperature. If it cools, we rapidly get a drop in albedo, which allows in more sun, and the balance is restored. If it warms, very soon thereafter albedo increases, we get less sun, and again the balance is restored.”

I agree there appear to be significant negative feedback systems working to prevent runaway effects. However, this seems to imply that we would never get a significant temperature change. However, we know that there have been well-documented warmer and cooler periods even just since the little ice age.

How do you account for these changes given the negative feedbacks?

kb

Good question. I covered a variety of possibilities in my initial post some years ago entitled “The Thermostat Hypothesis“. See the section called “Gradual Equilibrium Variation and Drift”.

In passing, I’d say that paper, from five years ago, has held up well.

w.

108. oops meant to say “Good point – this would be very interesting to compare, do you agree Willis?”

109. Willis Eschenbach says:

rgbatduke says:
February 25, 2014 at 7:52 am

Robert, as always, thank you for your detailed and insightful posting. I was with you until I got to this part:

It is partly because this sort of instability — or global multistability, with entirely distinct characters of strange attractor families appearing in the empirical record — that I think it is, on the whole, wiser not to kick the climate in the balls when we have no idea where it will end up. Increasing CO_2 in a strongly coupled nonlinear system could just as easily trigger the next ice age as cause thermageddon from heat.

You don’t believe me? Take a gander at the predator prey problem. When the numbers stay near the attractor, life is good for foxes and rabbits. Few rabbits starve, few foxes starve, fox/rabbit numbers stay close to some sort of “optimal” number for the presumed problem ecology. Bump either the number of foxes or the number of rabbits and all you do is kick the system into a large limit cycle, one that in time will carry both foxes and rabbits closer to extinction. Exactly the same thing will happen if one “suddenly bumps” e.g. \alpha(t) or the other parameters, makes the attractor jump farther away from the existing population values. If you simply add a certain amount of dynamic stochastic noise to the parameters, basically “shake up” the attractor so it does a random walk (constrained or unconstrained) since there are no dissipative terms in the coupled ODEs that cause the system to stabilize and relax to a bounded orbital range, it is quite likely that the system will get “shaken” into less and less stable orbits, increasing the probability of catastrophe.

We could all argue about how likely this sort of catastrophe is for the real climate, but the fact of the matter is that we have no idea, and our models don’t come close to being able to explain the observed climate variability.

Actually, we do have a very good idea of how likely this sort of catastrophe is for the real climate—as near as we can tell, it never happened in the last few hundred million years. We haven’t spiraled into a snowball earth, nor have we gone into Venusian heat death, despite large changes in the “forcings”.

You say we shouldn’t kick the climate in the balls because it might go haywire … you mean like say slamming a million-tonne comet into the Gulf of Mexico? Yeah, it blew things right out of the water … then the dust settled and guess what? Right back to the same old same old.

How did we get back there? Well, since the physics governing the time of the daily formation of the cumulus and cumulonimbus hadn’t changed, that meant the equilibrium temperature hadn’t changed, and so we ended up where we started.

As a result, while I agree with you about the complexity of the system, I disagree strongly about its fragility or instability. The only possible way that the planetary temperature could stay so stable (or recently, stay so bi-stable) for hundreds of millions of years is if there is a strong, robust, quick-recovering, disaster-resistant thermoregulatory system with a temperature based threshold … and by good fortune, that’s exactly what we have. The global temperature is a function of the physics of wind and wave and cloud and positions of the continents, it has little to do with changes in forcing … as the Mauna Loa record clearly shows. Clear-sky solar forcing dropped greatly all across the Pacific … but the temperature didn’t drop at all. Why didn’t it drop? I say in response to weakened heating, clouds formed later in the day. Bear in mind that we’re discussing a deficit of say 10 W/m2 or so, or 240W/hrs over the day. At noon in the tropics, you’re getting up to a kilowatt of power from the sun. So the deficit would be made up in its entirety by something like a half-hour delay in the average time of cloud onset …

One of the amazing parts of that system of control is that it’s virtually invisible … I mean, who would notice if the clouds on average formed a bit earlier or later? But it is that day by day response that keeps the temperature within such tight bounds.

So for the climate, the Lotka-Volterra equations are a terrible analogy. We see absolutely nothing in the climate like the huge predator prey swings. The global average surface temperature in the 20th Century didn’t vary more than ± 0.1%, a tenth of a percent … where will you find anything like that in a Lotka-Volterra evolution? L/V is all about wild highs and lows in response to changes in forcings, and the climate is all about hardly any swings in response to changes in forcings.

As always, it is a joy to read your clear and insightful comments. As your steel chips away at the dark flint, sparks of thought fly … a pleasure.

w.

110. Willis Eschenbach says:

MikeN says:
February 25, 2014 at 9:19 am

Does the paper actually claim the volcanoes did it? The press reports I’ve seen all seem to say only that ‘volcanoes cause cooling.’ There is no detail where they actually argue that there is more volcanoes now than before. It would be like if I said StefanBoltzman says warmer objects emit more heat into space, and argued that that is the reason for the pause.

Yep, that’s what they say. From their Abstract …

Here we present a detailed analysis of the impact of recent volcanic forcing on tropospheric temperature, based on observations as well as climate model simulations. We identify statistically significant correlations between observations of stratospheric aerosol optical depth and satellite-based estimates of both tropospheric temperature and short-wave fluxes at the top of the atmosphere. We show that climate model simulations without the effects of early twenty-first-century volcanic eruptions overestimate the tropospheric warming observed since 1998. In two simulations with more realistic volcanic influences following the 1991 Pinatubo eruption, differences between simulated and observed tropospheric temperature trends over the period 1998 to 2012 are up to 15% smaller, with large uncertainties in the magnitude of the effect.

111. Willis Eschenbach says:

Kristian says:
February 25, 2014 at 9:25 am

Willis, like Bob Tisdale has pointed out to you on many occasions, the global temperature rise in 1982/83 is clearly caused by the massive El Niño that year.

Yes, and as I’ve pointed out to Bob Tisdale on many occasions, I think that the El Nino pump functions to move warm water to the poles when too much heat builds up in the Pacific. As a result, I see the El Nino pump as a result of increasing global temperatures rather than a cause …

Yet, there’s a very stunted global response.

So your claim is that you can disentangle the climatic effect of three different things, 1) volcanoes, 2) temperature-based El Nino indices, and 3) other global temperature fluctuations from unknown causes, and you can tell us that there is a “stunted” temperature response to El Chichon? I fear I haven’t seen the math on that one.

You are correct that the Pacific leads the planet, and that the tropics leads the Pacific. The tropical Pacific warms and cools first, followed by the rest of the globe. In part this is because the generally clear tropical ocean waters are able to absorb large amounts of solar energy without changing temperature very much.

Over the following six months or so, this energy is released back into the system, with the natural result that the rest of the planet warms.

But that doesn’t mean that the El Nino pump somehow explains the variations of the planetary temperature. The El Nino pump RESPONDS to high temperatures, it doesn’t cause them. The pump just kicks in whenever too much heat builds up in the tropical Pacific, and it moves the warm water to the north and south poles.

It’s actually an ingenious design for a lovely thermoregulatory system. You use the heat in the ocean to warm the planet, so you always have a reservoir of heat to draw on. To ensure that the heat reservoir is always full, it fills up to the brim. And at that point the El Nino pump kicks in, skims off the excess heat to the poles, exposes the cooler subsurface waters to cool the atmosphere, and then the amazing Pacific-wide pumping system vanishes until it is needed again.

And the significant global temperature drop between 1992 and 1995 came during a period of mostly positive to distinctly positive ENSO-conditions. It goes the opposite way of what one could expect.

It is exactly what I’d expect. After El Chichon, global temperatures rose. After El Chichon, the El Nino index rose. After Pinatubo, temperatures fell. After Pinatubo the El Nino index fell. I’m not sure why you think that is significant.

Here’s the El Nino 3.4 Index, blue lines show dates of eruptions:

Or if you’d prefer, here’s the Multivariate ENSO Index, MEI:

As you can see in both cases, rising index after El Chichon, falling index after Pinatubo …

All the best,

w.

112. FundMe says:

Right on, what a good read, both Willis and the comments. I think that I am now less ignorant than when I started reading… Thanks

113. Jim G says:

http://www.mbari.org/volcanism/ShortStory.htm with link to: http://volcano.oregonstate.edu/submarine
Conjecture here based upon projection of known undersea volcanic activity is that 75% of all such activity occurs under water. Makes some sense since 70% of the Earth’s surface is under water. If anywhere near accurate, that is a great deal of heat and gases going into the oceans at mostly unknown times and places. So, what is going on on land is only the tip of the iceberg, or volcano in this case.

114. Kristian says:

Willis.

I can really see why Tisdale, after having explained and shown you so many times how one can clearly see the impact globally of the two large volcanic eruptions of the last 35 years, why he bothers no more. Because on this you simply refuse to see the obvious even when it stares you right in the face. There simply is no talking to you. You’ve just made up your mind. And that’s it.

Try looking at this graph, global SST vs. NINO3.4 (lagged by 2 months), 1988-98:

Are you telling me that you do not see the impact of the Pinatubo eruption on global SSTs between ’92 and ’95? What, then, caused that ridiculously obvious global dip in temperatures just after the eruption if not the eruption itself? It sure wasn’t ENSO. What other mechanism has the ability to completely and utterly counter ENSO globally for a three year period?

115. Dr. Strangelove says:

Willis,

Solomon is wrong to attribute the “pause” to volcanic eruptions since there is no big eruption since 1998. But I’m afraid you also got it wrong.

As mentioned before, your 14 W/m^2 is not comparable to 3.7 W/m^2/K. The latter is climate sensitivity without feedback. It is not necessarily due to CO2 forcing. Actually any forcing will do. The forcing attributed to CO2 is 1.66 W/m^2 since pre-industrial era according to IPCC. This CO2 forcing is a global radiative imbalance at TOA. Radiative balance is incoming radiation minus outgoing radiation. What you calculated are changes in surface down welling radiation locally at Mauna Loa. Not comparable to CO2 forcing.

The radiation absorbed by the atmosphere will warm the surface since it is tightly coupled with mid-troposphere temperature. Your 14 W/m^2 should have warming effect on the surface. And if you look at your Figure 2 closely, you will see an increase in temperature 1990-93. This is a local effect since the temperature and forcing are both local. Globally, there’s drop in temperature 1991-93 from Figures 4 & 5 presumably due to Mt. Pinatubo eruption.

116. Ulric Lyons says:

“But that doesn’t mean that the El Nino pump somehow explains the variations of the planetary temperature.”

The highest global temperatures do tend to be during an El Nino and not after, unless there is a lot of stratospheric aerosols at the time of course.

“The El Nino pump RESPONDS to high temperatures, it doesn’t cause them. The pump just kicks in whenever too much heat builds up in the tropical Pacific..”

It is a build of of heat in the Pacific, and it responds to a drop in solar forcing, whether that be stratospheric aerosols causing dimming at the surface, or a large enough drop in the solar wind speeds to effect global teleconnections, as in the very clear examples of 1997/98 and 2009/10:

117. Steve Fitzpatrick says:

Hi Willis,

I don’t think AOD generates anywhere near the loss of net solar energy that you have calculated. This is mostly because the AOD is a measure of how much the intensity of an incident light beam is diminished along the original direction of that beam. Most of the light that is scattered by volcanic aerosols is “forward scattered” at relatively shallow angles away from the original direction, very little is actually reflected at backward angles. (A bit is also absorbed by the aerosol particles themselves, causing a bit of warming, as we can see in the satellite temperature history for the stratosphere in the period following each major eruption.) Forward scattering dominates for all particles in the atmosphere that are larger than about 50 nanometers (and volcanic aerosols are much larger than 50 nm).

So even though the direct intensity of the sun is reduced by the amount you calculate, most of that reduction is not actually lost to space…. most is just converted into diffuse light, and a little is absorbed and converted to heat within the atmosphere. The actual reduction in solar energy reaching Earth is far lower than you calculated. NASA GISS multiplies tau by 23 to estimate the average global reduction in watts per square meter.

You can see the effect of forward scattering by looking at the sky when there is a bit of smoke/haze in the air; you will see that the sky at all angles anywhere near the sun is very bright, and much brighter than it would be on a perfectly clear day. That bright sky surrounding the sun is due to forward scattered light. It is much like the difference between a sand blasted light bulb and a clear light bulb; the total light exiting the bulb is the same, but it is more diffuse for the bulb with an irregular surface. I have read that diffuse light is actually quite good for plant growth, because more leaf area is illuminated, since there are no dark shadows cast by one leaf on another when light is arriving over a wide range of angles.

118. Alex says:

People seem to use the word ‘aerosol’ in a vague fashion. I can never be sure what they mean. Is an aerosol everything that spews into the atmosphere? Particulate matter and gas? To my mind they are totally different. A gas is not a blackbody and only ‘works’ in specific wave bands ie. absorption/emission lines. A particle is a blackbody and emits/absorbs in the broadband. The radiation physics are totally different.

119. Rolf says:

Doublings? Either I’m confused, or you misstated something slightly.
According to the IPCC, climate sensitivity is 3° per doubling of CO2, and a doubling of CO2 is a forcing increase of 3.7 W/m2 … and Mauna Loa was running at 14W/m2 shy of normal, that’s almost four doublings of CO2.
Did you mean almost four times? Four doublings of 3.7 is 59.2; four times (two doublings) is 14.8.
Or am I just missing something in my current decaffeinated state?

120. Alex says:

I enjoy Willis’s ability to take existing data( no matter how skewed it might be) and still be able to make a point. He has a patience with the human race that I don’t. I hope his heart condition is better now and he is getting enough clips over the head from his family to keep him mellow.

121. johnmarshall says:

No, no, no. Willis you are giving the planet 24 hour sunshine. This is NOT reality.
Reality has a night time with heat loss and zero heat gain. You TOA radiation can ONLY be spread over a HEMISPHERE giving an average of one half the total. This is where the IPCC got it wrong, and introduced the GHG theory to make up the enormous difference and makes the GHG effect HOTTER than the sun.
As I explained, but you obviously did not read, your 240W/m2 does not give enough heat to run the water cycle because you need liquid water for this.
My quoted figures for surface energy is VERIFIABLE by measurement. Or do you prefer to massage figures to fit your crap theory.

Again GET REAL.

122. Kristian says:

Willis Eschenbach says, February 25, 2014 at 4:16 pm:

“But that doesn’t mean that the El Nino pump somehow explains the variations of the planetary temperature. The El Nino pump RESPONDS to high temperatures, it doesn’t cause them.”

I’m talking about the ENSO process. The ENSO process involves the entire tropical/subtropical Pacific basin.

What drives the ENSO process in either direction (towards cooling or towards warming) over multidecadal periods is inconsequential for this discussion.

There is no question that global temperatures are held on a tight leash by the ENSO process, the administrator of our planet’s largest energy reservoir by far. Since 1970, global temperatures have only parted permanently with the NINO3.4 SSTa on three (3) occasions:

All of these sudden global upward shifts (first pointed out, described and explained by Bob Tisdale, as you most likely know) occurred at specific points where the pan-Pacific climate regime underwent abrupt and fundamental changes. The first one happened in the direct aftermath of the Great Pacific Climate Shift of 1976/77. It came about when the SO all of a sudden decided to plunge to a new mean level and stay there for the next 30 odd years. This saw a relative warming (OHC and SST) of the East Pacific and a relative cooling (OHC) of the West Pacific. (The SST of the West Pacific stayed flat.)

The next two shifts were clearly of West Pacific origin. They are not seen in the East Pacific. Bob Tisdale has thoroughly and meticulously explained how exactly these shifts came about.

It is also fascinating to see how the AMO, or rather the SSTa of the North Atlantic, is directly affected by the ENSO process through so-called atmospheric bridges – it varies with NINO3.4 (East Pacific) during the major El Niños, but is affected by the massive surface heat accumulation in the West Pacific directly on the heels of these specific El Niños, so that the following Atlantic La Niña response is significantly reduced.

123. Kristian says:

To accompany my last posting:

124. aaron says:

I would think that the tropics would stay relatively warm, the mid latitude temps would drop most. This would increase easterlies and therefore drive toward la nina conditions. Winds in the region would probably also mute the cloud/temp resonse in the region some, since they increase evaporation and the aerolos will prevent the vapor from reaching the upper atmosphere. This would be a neutral/positive feedback for the region (cooling the ocean/surface despite the low heat input), and a negative feedback for the world, preventing transfer of heat to the poles to be radiated away.

125. aaron says:

Rolf, the greenhouse effect dimishes as concentration rise, so each doubling give the same 3.7W/m^2.

126. rgbatduke says:

Could I impose upon you to explain the meaning of “linear” in this context and what the implications of that feature are?

I mean specifically that R and F only occur as first powers in the set of equations. The cross terms provide for an effectively nonlinear coupling, but the individual equations are (holding e.g. F constant and looking at the DE for R) 1st order linear equations.

Without the product in the cross term, related coupled first order linear ODEs can be reduced to second order linear ODEs — for example the pair of linear 1st order equations that reduce to the linear 2nd order harmonic oscillator equation. With such a cross term, one cannot really reduce the pair to a single second order equation at all, but if one did it would probably be nonlinear, I agree. In any event, the linearity or nonlinearity per se are at issue only in the sense that linear systems — if I recall correctly — typically do not have chaotic solutions, and the Lotke-Volterra equation has true Poincare cycles (indeed, trivial ones) rather than chaotic trajectories with divergences in phase space for all positive values of the parameters. This is characteristic of a wide class of mechanical systems to which Liouville’s theorem can be applied, but there are always ODE systems that are formally very “close” to linear systems with (eventually) closed trajectories that will exhibit chaos — there are a number of examples of oscillators that in a limit are classical closed systems, and for many values of the parameters are just such a system, but for certain values of the parameters or initial conditions become chaotic. My students often play with some of the systems — “Bender Bouncers”, double penduli, harmonically driven damped mass-on-a-rod penduli — numerically. It is great fun.

Mind you, I am far from expert in nonlinear ODEs and chaos. I know a bunch of stuff about it, and have played with at least some such equations extensively, but this is really difficult stuff and mathematicians spend careers working on it now — it isn’t like the linear stuff that was largely worked out in the 19th and early 20th centuries.

rgb

127. Willis Eschenbach says:

Rolf says:
February 25, 2014 at 11:29 pm

Doublings? Either I’m confused, or you misstated something slightly.

According to the IPCC, climate sensitivity is 3° per doubling of CO2, and a doubling of CO2 is a forcing increase of 3.7 W/m2 … and Mauna Loa was running at 14W/m2 shy of normal, that’s almost four doublings of CO2.
Did you mean almost four times?

Four doublings of 3.7 is 59.2; four times (two doublings) is 14.8.
Or am I just missing something in my current decaffeinated state?

Grab a cup of coffee. I was discussing four doublings of CO2, not four doublings of the forcing. CO2 acts logarithmically. It increases the forcing by 3.7 watts per doubling of CO2 … but the 3.7 W/m2 doesn’t double, the amount of CO2 (the atmospheric concentration) is what doubles.

w.

128. Willis Eschenbach says:

johnmarshall says:
February 26, 2014 at 3:13 am

No, no, no. Willis you are giving the planet 24 hour sunshine. This is NOT reality.
Reality has a night time with heat loss and zero heat gain. You TOA radiation can ONLY be spread over a HEMISPHERE giving an average of one half the total. This is where the IPCC got it wrong, and introduced the GHG theory to make up the enormous difference and makes the GHG effect HOTTER than the sun.
As I explained, but you obviously did not read, your 240W/m2 does not give enough heat to run the water cycle because you need liquid water for this.
My quoted figures for surface energy is VERIFIABLE by measurement. Or do you prefer to massage figures to fit your crap theory.

Again GET REAL.

First, let me invite you stuff your GET REAL up your fundamental orifice.

Second, since you have not provided a quotation of my words I don’t have a clue what you are getting all nasty and snarky and babbling on about. 24 hour sunshine? Say what?

Get a grip, grab a handful of politeness, quote my words and try again. But lose the attitude, it’s unbecoming in a person such as yourself, one so clueless as to try to attack me without quoting me …

w.

129. timetochooseagain says:

@Steve Fitzpatrick-I think most of the discrepancy is more due to there being a big difference between the local scale figures, and the global scale ones.

Which actually implies that there is a significant spatial gradient to the volcanic forcing. It would be a bad mistake to view such a case as analogous to the effect of a uniform forcing like CO2…

130. Gary Pearse says:

Good sensible stuff again. Your look at the unexpectedly minor temperature response to a huge reduction in surface insolation associated with volcanic activity over several years is a “QED” of the thermostat hypothesis. However I think it more compelling if it is possible to show from Ceres data the evidence of corresponding albedo reduction in the ITCZ caused by reduction (probably disappearance) of clouds at those precise times. It would also make you the best forecaster on the planet for the weather in the tropical zone looking forward 3yrs after a major volcanic eruption! What about those weather records during those years?

131. Willis Eschenbach says:

Gary Pearse says:
February 26, 2014 at 10:49 am

Good sensible stuff again. Your look at the unexpectedly minor temperature response to a huge reduction in surface insolation associated with volcanic activity over several years is a “QED” of the thermostat hypothesis. However I think it more compelling if it is possible to show from Ceres data the evidence of corresponding albedo reduction in the ITCZ caused by reduction (probably disappearance) of clouds at those precise times.

Sadly, CERES data only goes back to 2000 … however, I showed the changes in NH albedo following Pinatubo above, viz:

w.

132. Anton Eagle says:

Hi Willis,
Great post, as usual. And, I totally agree with your emergent phenomenon theory. It’s one of those “I thought everyone already knew this” kind of a thing… especially in climate study.

I spent much of my formative years in the Denver area, and, much like the tropics (but to a lesser degree), we experienced the exact same kind of temperature regulating phenomena as you describe in the tropics. The 2pm thunderstorm is a regular occurrence on the front range (everyone that lives there knows what I’m talking about)… but only if it’s hot enough (and humid enough, but that’s a separate thing).

That said, I would like a clarification on what “johnmarshall” is asking about… albeit I will try to ask much less rudely.

I think what he’s not getting, and frankly neither am I, is why in your calculation you divide the incoming radiation (minus albedo, etc.) by the entire surface area of the planet, rather than just the surface area of the exposed half of the sphere.

I will grant you, that it probably wouldn’t matter in terms of what you were looking for in this post. But, in general, shouldn’t we be looking at an average of 480 W/m^2 instead of 240 W/m^2 for the irradiated half of the planet? So, I would have thought that it should be…

1360 pi r2 / (4 pi r2) / 2 = 2720 / 4 ≈ 680 W/m2 average solar radiation.

I’m sure there’s some simple reason why it’s not… but I will be darned if I can see what it is? Am I missing something here?

Thanks. And thanks again for your diligence, and your patience.

133. GregK says:

rgb,
if your rabbits get out of kilter and reproduce to the level that they over exploit their food source, to the level where it cannot recover in the presence of rabbits, then you may lose both rabbits and foxes. Both gone and even then the food source may not recover as it might have been replaced by hardier and less succulent plants.

Not sure what this has got to do with climate except in relation to unstable equilibrium

134. johnmarshall says:

If you divide the insolation by 4 you are spreading it over the entire planet’s surface. This is NOT reality. Reality has a 12 hour period that receives zero energy but still radiates. The model has to relate to reality or you get the wrong answer, as you have.
That 240W/m2 does not come from the surface. Using the adiabatic environmental lapse rate you can calculate that this radiation is from 5-6 Km ABOVE the surface, or the cloud tops which would be sensible given all the heat locked up in those clouds thanks to latent heat.
In the sun’s zenith position radiation, as measured, is around 960W/m2 which gives, using S/B formulae a possible temperature of 88C Temperatures have been measured near this on the surface in some deserts. Convection is the Primary Heat Remover from the surface not radiation. Mixed with latent heat explains why rainforests are cooler than deserts, the very opposite of that predicted by the GHG effect.

135. Steve Fitzpatrick says:

timetochooseagain says:
February 26, 2014 at 9:24 am

“@Steve Fitzpatrick-I think most of the discrepancy is more due to there being a big difference between the local scale figures, and the global scale ones.”

There is some influence of local versus global, of course, since average solar intensity varies with latitude and season. But that does not explain almost an order of magnitude overestimate of the net volcanic forcing made here by Willis. The issue is mainly that AOD (Tau) is not a measure of light lost to space via scattering by aerosol particles, it is a measure of the total fraction of incident light scattered by those aerosol particles, in all directions. Most of the scattered light is scattered in forward directions and ends up being absorbed by the Earth as diffuse sunlight rather than direct sunlight, and is not lost to space. Only backward scattered light (which is a small fraction of the total scattered) is what is lost to space.

136. Willis Eschenbach says:

johnmarshall says:
February 27, 2014 at 3:02 am

If you divide the insolation by 4 you are spreading it over the entire planet’s surface. This is NOT reality. Reality has a 12 hour period that receives zero energy but still radiates. The model has to relate to reality or you get the wrong answer, as you have.

John, you are correct that an average is not reality. Reality is reality. Averages are averages.

That said, averages can be useful. For example the 24/7 global TOA average sunlight, which is 340 W/m2. It’s both useful and accurate despite not being reality.

In particular, it allows us to do things like global energy budgets, or calculate how much energy is going into the ocean, that kind of thing.

It’s useful in part because it is accurate. By that I mean if I use say the 340 W/m2 global average insolation, I can multiply that by the time involved (say a month), and that will give an accurate answer in watt-months/m2. By accurate, I mean that if you measure the radiation for the month, that’s the number you’ll actually get.

So I fear that your argument, that it is NOT reality doesn’t matter—it’s both useful and accurate, meaning it matches observations.

w.

137. Willis Eschenbach says:

Steve Fitzpatrick says:
February 27, 2014 at 10:04 am

timetochooseagain says:
February 26, 2014 at 9:24 am

“@Steve Fitzpatrick-

I think most of the discrepancy is more due to there being a big difference between the local scale figures, and the global scale ones.”

There is some influence of local versus global, of course, since average solar intensity varies with latitude and season. But that does not explain almost an order of magnitude overestimate of the net volcanic forcing made here by Willis. The issue is mainly that AOD (Tau) is not a measure of light lost to space via scattering by aerosol particles, it is a measure of the total fraction of incident light scattered by those aerosol particles, in all directions.

Thanks, Steve. Since I didn’t use AOD (aerosol optical depth) except for comparison purposes, but instead I used the Mauna Loa transmission data (percentage of sunlight making it through clear air), I’m not sure what your point is.

w.

138. Joe Born says:

rgbatduke: “[T]he Lotke-Volterra equation has true Poincare cycles (indeed, trivial ones) rather than chaotic trajectories with divergences in phase space for all positive values of the parameters.”

A belated thank you for your response. (I was traveling, and your response escaped my attention.)

I’m afraid I’ll go to my grave knowing nothing further about non-linear differential equations, so for the excerpt above was enlightening.

139. Steve Fitzpatrick says:

Willis,
“I’m not sure what your point is.”

My point is that your calculation of energy loss is wrong.

If you look at the NASA AOD historical curve (http://data.giss.nasa.gov/modelforce/strataer/) and compare it to the Mauna Loa direct transmission data (http://www.esrl.noaa.gov/gmd/grad/mloapt.htm) you can see that the two histories (where they overlap) are essentially the same data: the Mauna Loa transmission is close to (1 – AOD). Whether you consider AOD or consider direct solar transmission intensity, the calculation of energy lost to space is MUCH less than you calculated. The problem with your calculation is that you assumed a reduction in direct solar intensity means that reduction is 100% lost to space. It is not. Most of the intensity lost from the sun’s direct transmission is scattered in forward directions. That forward scattered light still reaches the Earth as diffuse light; it is not lost to space as your post suggests. Your error is not small, it is near an order of magnitude, because the vast majority of light scattering by volcanic aerosols is forward, not backward.

140. Willis Eschenbach says:

Steve Fitzpatrick says:
February 28, 2014 at 2:50 pm

Willis,

“I’m not sure what your point is.”

My point is that your calculation of energy loss is wrong.

If you look at the NASA AOD historical curve (http://data.giss.nasa.gov/modelforce/strataer/) and compare it to the Mauna Loa direct transmission data (http://www.esrl.noaa.gov/gmd/grad/mloapt.htm) you can see that the two histories (where they overlap) are essentially the same data: the Mauna Loa transmission is close to (1 – AOD). Whether you consider AOD or consider direct solar transmission intensity, the calculation of energy lost to space is MUCH less than you calculated. The problem with your calculation is that you assumed a reduction in direct solar intensity means that reduction is 100% lost to space. It is not. Most of the intensity lost from the sun’s direct transmission is scattered in forward directions. That forward scattered light still reaches the Earth as diffuse light; it is not lost to space as your post suggests. Your error is not small, it is near an order of magnitude, because the vast majority of light scattering by volcanic aerosols is forward, not backward.

Thanks, Steve. Although that makes your claim clearer, it doesn’t provide any actual support for your claim.

We know for a fact that some of the energy is reflected, some of it is absorbed, some of it is scattered, and some is transmitted. I have assumed that the majority of what is not transmitted is either reflected or absorbed.

And indeed, the usual explanation of the effect of sulfates in the stratosphere is that they are white in color, and they cut down the sunlight.

There is another, more fundamental difference between the AOD and the MLO data. The AOD data is solely for the stratosphere. The MLO data includes part of the troposphere as well.

Now, I agree that I’ve not accounted for scattered light. You are 100% correct about that. So let’s assume that it’s 1/2 scattered forwards, 1/4 absorbed, and 1/4 reflected. That’s likely not too far from reality. In that case, instead of reductions of 7.5 watts per square metre on average (El Chichon) or 14 W/m2 (Pinatubo), it would be about half of that. That calculates to 3.7 W/m2 for El Chichon and 7 W/m2 for Pinatubo.

My point remains. The IPCC and the prevailing climate theory says that “climate sensitivity” is 1.5-4.5 W/m2 for a forcing increase of 3.7 W/m2 from a doubling of CO2.

To be conservative I’ll use 2° per doubling. Now that’s equilibrium sensitivity, and according to the models transient sensitivity is about three-quarters of that. So for a doubling of CO2 (3.7 W/m2) they say we should see cooling of 1.5°. This means for the El Chichon revised reduction in incoming solar (3.7 W/m2) we should see about 1.5° of cooling … and for the 7 W/m2 reduction from Pinatubo we should see about twice that, a 3°C drop … but we see nothing.

Despite whatever numbers you might put on it, or what interpretation you might give it, observations show that at Mauna Loa there was no visible effect on the temperature from the volcanic eruptions.

Best regards,

w.

141. Steve Fitzpatrick says:

Willis,

Thank you for your reply. You say “So let’s assume that it’s 1/2 scattered forwards, 1/4 absorbed, and 1/4 reflected.” Unfortunately, it is nothing like that. The longer lived volcanic aerosols are mainly sulfuric acid (liquid) droplets, and are mainly in the stratosphere. Tropospheric aerosols disappear pretty quickly. In the size range of ~0.5 to ~1 micron diameter, the total forward scattering by droplets is on the order of 100 times greater than backward scattering (Borhen and Huffman, ‘Absorbtion and Scattering of Light by Small Particles’, Wiley, 1998, page 115). Now, there are some solid volcanic particulates which absorb some light and cause stratospheric warming. These can be non-spherical in shape, and those same solid particles may reflect a little more light than can a liquid droplet, but the overwhelming majority of the measured reduction in solar intensity following a volcanic eruption is in fact forward scattered light. The NASA GISS estimate for net reduction in solar intensity (23 times the AOD, or about 3.7 watts/M^2 for a brief peak reduction after Pinatubo) seems perfectly reasonable. Your estimate of ~30 watts/M^2 reduction at Mauna Loa after Pinatubo is not at all reasonable.

We disagree about the influence of Pinatubo on surface temperatures, because, IIRC, you discount the influence of the El Nino warming which followed very shortly after Pinatubo. If that warming is taken into account (see my post: http://rankexploits.com/musings/wp-content/uploads/2013/06/Figure5.png, where ENSO is accounted for) the cooling influence of Pinatubo is clear.

142. Dr. Strangelove says:

Willis,
Your computed forcing from Pinatubo of 14 W/m^2 is not global. Granting this is caused by aerosols circulating in the stratosphere. The aerosols are carried by the jet stream passing over Hawaii and the Pacific ocean. The stream is about 800 km wide or covers 6% of earth’s area. Convert your 14 W/m^2 to global forcing = 0.878 W/m^2.

How much change in global temperature will that cause? Using the SB equation, a cooling of 0.17 C. How much global cooling was observed in 1991-92? Lo and behold exactly 0.17 C! Your computed forcing is correct, if you convert it to global.

143. Willis Eschenbach says:

Dr. Strangelove says:
March 1, 2014 at 6:19 am
Your computed forcing from Pinatubo of 14 W/m^2 is not global. Granting this is caused by aerosols circulating in the stratosphere. The aerosols are carried by the jet stream passing over Hawaii and the Pacific ocean. The stream is about 800 km wide or covers 6% of earth’s area. Convert your 14 W/m^2 to global forcing = 0.878 W/m^2.

Nice theory … but it runs aground on the reef of ugly facts. From the link I gave in the head post we have the distribution of the aerosols for the volcanoes:

Note that the distribution of the aerosols of recent volcanoes, particularly of Pinatubo, is global, extending all the way to the poles …

Doc, I put those links in my head post for a reason … can you guess what it might be?

How much change in global temperature will that cause? Using the SB equation, a cooling of 0.17 C. How much global cooling was observed in 1991-92? Lo and behold exactly 0.17 C! Your computed forcing is correct, if you convert it to global.

Lo and behold, your calculation is nonsense, the forcing was global. Do your homework first, it avoids this kind of embarrassment.

w.

144. Dr. Strangelove says:

Willis,
Try to be polite. It’s just basic good manners taught in kindergarten. I never use words like “nonsense” and “embarrassment” to critique your work because they are counterproductive.

Look at carefully your chart at circa 1990. The optical depth at latitude 0 (equator) is close to 0.006 while at latitude 90 (poles) is close to 0.01. Now the same NASA website ( http://data.giss.nasa.gov/modelforce/strataer/ ) where you got this chart says the relationship between instantaneous forcing Fi and optical thickness t is Fi (W/m^2) = -27 t

Using this equation, the instantaneous forcing is -0.162 W/m^2 near the equator and -0.27 near the poles. Now that’s very far from your -14 W/m^2 and closer to my estimate -0.878 W/m^2.

BTW if you believe in Stefan-Boltzmann law of radiation, you will immediately see that -14 W/m^2 will give you a change in temperature of -2.8 C. The observed change in global temperature in 1991-92 is -0.17 C. Again very far from -2.8 C.

Cheers

145. Dr. Strangelove says:

Willis,
The likely reason why NASA equation gives lower forcing than my estimate is they measured optical depth at 550 nm. That’s only blue light. The solar electromagnetic spectrum ranges from 100 nm to over 3,000 nm. More than half is in the infrared spectrum. If you include the whole spectrum, you will definitely get a higher forcing closer to my estimate.

146. Dr. Strangelove says:

Correction: 550 nm is actually green light

147. Dr. Strangelove says:

Willis,
We should be looking at 1992 optical depth (after Pinatubo eruption) which is 0.1 or equal to -2.7 W/m^2. This is quite large compared to observed change in global temperature in 1992 = -0.15 C. This is stratosphere optical depth but the temperature is on surface. The radiation has to pass the troposphere before reaching the surface. Troposphere is much denser than stratosphere. The forcing will diminish when it reaches the surface. My guess is it will decrease to about -0.878 W/m^2.

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