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Climate Hustle

Do volcanoes emit more CO2 than humans?

What the science says...

Select a level... Basic Intermediate

Humans emit 100 times more CO2 than volcanoes.

Climate Myth...

Volcanoes emit more CO2 than humans

"Human additions of CO2 to the atmosphere must be taken into perspective.

Over the past 250 years, humans have added just one part of CO2 in 10,000 to the atmosphere. One volcanic cough can do this in a day." (Ian Plimer)

The solid Earth contains a huge quantity of carbon, far more than scientists estimate is present in the atmosphere or oceans. As an important part of the global carbon cycle, some of this carbon is slowly released from the rocks in the form of carbon dioxide, through vents at volcanoes and hot springs. Published reviews of the scientific literature by Mörner and Etiope (2002) and Kerrick (2001) report a minimum-maximum range of emission of 65 to 319 million tonnes of CO2 per year. Counter claims that volcanoes, especially submarine volcanoes, produce vastly greater amounts of CO2 than these estimates are not supported by any papers published by the scientists who study the subject. 

The burning of fossil fuels and changes in land use results in the emission into the atmosphere of approximately 30 billion tonnes of carbon dioxide per year worldwide, according to the EIA. The fossil fuels emissions numbers are about 100 times bigger than even the maximum estimated volcanic CO2 fluxes. Our understanding of volcanic discharges would have to be shown to be very mistaken before volcanic CO2 discharges could be considered anything but a bit player in contributing to the recent changes observed in the concentration of CO2 in the Earth's atmosphere.

Volcanoes can—and do—influence the global climate over time periods of a few years but this is achieved through the injection of sulfate aerosols into the high reaches of the atmosphere during the very large volcanic eruptions that occur sporadically each century. But that's another story...

Recommended further reading on CO2 and volcanoes can be found here: Terry Gerlach in Earth Magazine ; USGS

Last updated on 31 May 2014 by John Cook. View Archives

Printable Version  |  Offline PDF Version  |  Link to this page

Related Arguments

Further reading

Tamino has posted two examinations of the "volcanoes emit more CO2 than humans" argument by looking at the impact of the 1991 Pinutabo eruption on CO2 levels and the impact of past super volcanoes on the CO2 record.

The Global Volcanism Program have a list of all volcanoes with a Volcanic Explosivity Index (VEI) greater than 4 over the past 10,000 years.


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Comments 101 to 150 out of 282:

  1. ...

    5. internal variability greater than thought


    About efficacy of forcings:

    I haven't actually read much about that but here's what I would expect:

    Consider a forcing by

    Solar TSI
    LW (greenhouse) forcing
    volcanic stratospheric aerosols
    tropospheric aerosols
    surface albedo

    For any given forcing - let's start with radiative forcing - there is:

    1. a global average TOA (top of atmosphere) value, R-TOA.

    2. a global average tropopause value, R-tp

    3. a global average surface value, R-sfc.

    4. Some spatial-temporal (seasonal, perhaps interannual) variation in either of R-TOA, R-tp, R-sfc, which I will simply refer to here as R-var.

    5. Some climatic response which results from the effect of R and feedbacks.


    To start with, we might assume an approximation that the climatic response in so far as global average is concerned, is similar to any R-tp or R-TOA for any forcing. Then we might look for deviations from that.


    R-TOA is the forced net change in downward minus outgoing radiation 'at' the top of the atmosphere.

    R-tp is different then R-TOA; both are different from R-sfc - First:

    An increase in solar TSI - if the same % increase at all wavelengths - the forcing is a heating distributed (unevenly) through the atmosphere and surface. R-TOA is the sum of all of this heating; R-tp is only the heating below the tropopause and is therefore somewhat less than R-TOA; R-sfc is only surface heating and is therefore less than R-tp.

    Typically changes in solar TSI are greater in UV in particular, so a larger fraction than otherwise of solar forcing goes into heating the upper atmosphere, thus decreasing R-tp even further.

    Greenhouse forcing is a reduced cooling to space, which is a heating of the surface and/or lower atmosphere. The cooling to space of the stratosphere and above, however, increases, while the heating of higher atmospheric layers by the surface and/or lower troposphere decreases. Thus for greenhouse forcing, R-TOA will be a little less then R-tp. Starting at minimal LW opacity, R-sfc might be greater than R-tp (?), but at least for CO2, my impression is increases from the current amount result in greater R-tp than R-sfc. Water vapor is a feedback, but applying the same concepts to water vapor, I think, at least under some conditions, R-sfc is greater than R-tp for water vapor. This is at least in part due to water vapor's increasing concentration toward the surface. Ozone concentration is also variable so greenhouse effects of ozone changes may be a bit different than the 'typical' well-mixed greenhouse gas.

    The exact relationship between R-tp, R-sfc, and R-TOA for even well-mixed greenhouse gases (like CO2, CH4, N2O, CFCs) (they have some spatial and seasonal variations but not to the degree of ozone or water vapor) could vary because they have different spectrums, and temperature (and water vapor, ozone, cloud content) varies with height (and other dimensions), they may overlap with each other and other things in different ways due to the above differences, and they have different initial amounts before changes occur.

    a decrease (to keep the same sign of forcings for more straightforward comparison) in volcanic stratospheric aerosols - this would reduce albedo. The aerosols reflect SW (solar) radiation back up from the stratosphere, thus cooling the troposphere and surface but possibly heating the air above; and perhaps heating the stratosphere a little bit (? I think the stratosphere or some part of it actually warms up after relevant eruptions - this might be due to the nonzero absorption of solar radiation by the aerosols themselves) (some of the solar radiation is scattered downward or sideways - for a near-overhead sun (middle of day, summer midlatitude, or at low latitude), this can increase the path length before reaching the surface, thus increasing the portion absorbed in the air...) ... SO scattering of radiation is complicated (but not so much that it isn't understood), but reducing volcanic aerosols results in an R-sfc and R-tp greater than R-TOA, and I suspect R-sfc would be greater than R-tp.

    tropospheric aerosols

    A decrease in the albedo from reduced scattering by aerosols:

    R-sfc will be greater than R-tp and R-TOA as some of the reflected and scattered radiation had been absorbed by air and clouds.


    An increase in the atmospheric heating by increased absorption of aerosols:

    R-TOA and R-tp will be positive while R-sfc is negative.

    4c. scattered radiation can be subsequently absorbed in the air; the total effect of aerosols is not simple, but again, it isn't an impossible riddle either.

    Decrease in albedo due to surface conditions: The change in albedo actually at the surface may have to be greater than that which results at TOA, due to clouds, but also time of day and year issues, and latitude. Anyway, reflected solar radiation has a second chance to be absorbed by the air, so the decrease in albedo because of surface conditions may result in R-sfc greater than R-tp and R-tp greater than R-TOA (but perhaps only slightly).


    R-tp may be (as it is in IPCC work) defined as that which occurs after the stratosphere and above have reached thermal equilibrium with the forced heating or cooling (R-TOA - R-tp) which occurs there (PS notice this is not the same as that equilibrium which would result after the climate response including the tropsophere and surface). If R-TOA is greater than R-tp, then the stratosphere, etc, will have warmed, so R-tp will be a little higher as a result due to increased downward LW radiation (or a decrease in net upward LW radiation). If R-TOA is less than R-tp, the opposite will be true. In other words, R-tp will get closer to the original R-TOA (But I don't think it would be equal to the original R-TOA - I expect it to still be less or greater than R-TOA, whichever was the case to begin with). R-sfc might also shift in the same direction but not as much so long as there are any greenhouse agents within the troposphere.

    Of course, in the full climatic response, however tropospheric heating (R-tp - R-sfc) is distributed within the troposphere, or however much it is, as an upper layer warms up, it reduces convective heat transport from below, thus the tendency is for the full effect of R-tp to propogate by convection to the surface, whatever R-sfc was. However, a larger R-tp - R-sfc and/or smaller or negative R-sfc value will tend to reduce convection from the surface - HOWEVER, after all feedbacks have occured, the radiative heating/cooling distribution may be different again. ***I think this would be less true for regionally-concentrated forcings (pockets of high aerosol concentrations, for example), because advection into and out of the area would prevent a radiative convective equilibrium on the regional scale, so perhaps this is partly why I hear of atmospheric brown clouds (dark absorbing aerosols) in particular reducing vertical motion by increasing stability.

    So a global average R-tp will tend to result in some global average tropospheric and surface temperature increase. Some other effects due to the vertical distribution may change the feedbacks that occur and thus the resulting temperature changes in the surface and troposphere - but to my knowledge that is not a big effect (?).

    The horizontal (and seasonal, if and when it matters (ozone)) variations could also affect the actual global average results. For example - the R-tp and R-TOA of albedo reduction from BC landing on snow/ice will likely be a little smaller than the R-sfc value (some radiation reflected from the surface can be reflected back to the surface by clouds, aerosols, and air molecules); furthermore and perhaps much more importantly, the effect is concentrated where a positive feedback is also concentrated (snow-ice albedo feedback). Thus the climate sensitivity could be expected to be larger to BC on snow/ice forcing than to some other forcings, to the extent that the forced heating is not entirely advected away from similar locations.

    As far as anthropogenic well mixed greenhouse gases (WMGHG - to adopt the acronymn I saw in a paper - this includes CO2, CH4, N2O, CFCs - well, at least a couple CFCs) compare to solar radiative forcing - the geographic distribution of R-tp is going to be at least a little similar on a broad scale - the LW forcing is highest in the subtropics because of the relatively dry cloud-free air and higher lapse rates; high cloud tops in the tropics prevent greenhouse gases below them from having any direct effect on R-tp; lower tropospheric and surface temperatures in general and smaller lapse rates at higher latitudes reduce the difference in outgoing LW radiation (at least at tropopause level - and the tropopause is lower there, too) that would result from changing greenhouse gas concentrations (and the lower surface temperatures. Solar forcing will generally be greatest at low latitudes, during the day, and/or in summer, where there are fewer clouds, reflective aerosols, darker surfaces (ocean, forests), etc. For example, the dry subtropics (but unlike WMGHGs, solar forcing would not be as large over dry light-colored landscapes as it would be over dark oceans). Etc. R-tp will be higher than otherwise when there is less stratospheric ozone. There is a latitudinal and seasonal ozone variation - there tends to be more ozone at higher latitudes in winter/spring, I think - because while stratospheric ozone is produced more at low latitudes, winter stratospheric circulation brings it into high latitudes, and actually 'piles it up' there, in part (if not in whole) because the stratosphere is thicker at higher latitudes (lower tropopause)...


    Of course anthropogentic GHG forcing is expected to result in a cooler stratosphere (observed - although stratospheric ozone depletion also has a similar effect - but each can be calculated so it should be possible to attribute portions of cooling), and greater warming at nights during days near and at the surface over land (not much diurnal cycle to begin with over oceans because of heat capacity) - (also observed, at least somewhat). Positive solar forcing that would warm the surface and troposphere would also warm the stratosphere (not observed). However, because of this, there could be effects on atmospheric circulation that are different than for GHGs, which might affect climate sensitivity (but how much and in what direction?).***

    (Quietman - if you want to show a reduced climate sensitivity by way of greater total forcing, you might try looking into how solar forcing, including non-TSI or non-UV effects, affect not only the stratosphere, but also the ionosphere, and for example the E-region dynamo, and how geomagnetic effects also affec the E-region dynamo and solar-magnetospheric-ionospheric interactions, and what any resulting circulation pattern changes would be, and if and how that propogates downward. I am not saying that I expect you to be successful, but it's a thought - while I have my doubts, I think it's got a lot more potential than submarine volcanism, solar jerk, tides on sun, Spencer's PDO+ENSO work, Spencer's cloud forcing work, urban heat island dominance, or the idea that there hasn't been a recent spurt of global warming above and beyond internal variability.)
  2. "so perhaps this is partly why I hear of atmospheric brown clouds (dark absorbing aerosols) in particular reducing vertical motion by increasing stability."

    Actually, the full effect may be an increase in stability to moist convection by reduction in evaporation; in so far as dry convection is concerned, while the heating has been moved upward from the surface, it won't generally be all the way up to the tropopause; while there will tend to be increased stability beneath such a brown cloud, there will tend to be reduced stability above it. The heating of the brown cloud itself will tend to cause a low pressure beneath it and a high pressure above it, and the brown cloud itself will tend to rise.
  3. ... of course, I've never been quite clear on 'global dimming - H2O evaporation' - of course if water is being heated to higher temperature, the tendency is for faster evaporation under the same wind and relative humidity. But there has been global warming along with 'global dimming' (? - according to some comments at "Arctic sea ice..."), so how does decreased solar radiation reaching the surface affect evaporation independently of temperature? Is it analogous to the photoelectric effect - in this case, individual higher energy photons are able to kick off H2O molecules into the air even if the temperature is low (but not too low)? Sounds conceivable, but then again, the absorption of solar radiation is distributed within a depth of water from the surface downward; less so for the shortest wavelengths, red light and solar IR, but I suspect it's a tiny tiny fraction that would be absorbed within a 'molecular layer' or two from the surface.
  4. Since much of what I am about to say applies to the "Arctic sea ice"... , I'm going to post a few comments there now. If after that I haven't covered some of what was brought up here in comments 87-95, I'll come back here.
  5. Patrick
    Your explanations and willingness to look at both sides is exactly why I asked you to come to this site. In most cases I can see your logic and find it convincing.

    Keep in mind that this type of science is new to me. I have a beckground in engineering research (product developement) and bench testing emissions but I have never done well with theoretical math only logic and applied math, so keep it simple.

    Trust me, it is just as frustrating for me when someone points to a paper and claims it as fact without a logical explanation as it is when I get quoted from a bible passage. The fact that you don't resort to that is quite refreshing.
  6. Patrick
    In a new article at MSNBC titled ‘Dead’ planets might be livable after all
    they explain planetary tidal forces in the manner that I see them (inferring from the Solar Jerk) but carried to more of an extreme than we experience. The hypothesis is the same however, it's only a matter of degree.
  7. Patrick
    I found a little more background data:

    Evidence Mounts For Arctic Oscillation's Impact On Northern Climate: ScienceDaily (Dec. 20, 1999)- A growing body of evidence indicates that a climate phenomenon called the Arctic Oscillation has wide-ranging effects in the Northern Hemisphere and operates differently from other known climate cycles.

    Arctic Oscillation Has Moderated Northern Winters Of 1980s And '90s: ScienceDaily (July 10, 2001) - The Arctic Oscillation has been linked to wide-ranging climate effects in the Northern Hemisphere, but new evidence shows that in recent decades it has been the key in preventing freezing temperatures from extending as far south as they had previously.

    Synchronized Chaos: Mechanisms For Major Climate Shifts: ScienceDaily (Aug. 2, 2007) — In the mid-1970s, a climate shift cooled sea surface temperatures in the central Pacific Ocean and warmed the coast of western North America, bringing long-range changes to the northern hemisphere.

    It seems that someone has been ignoring this data for quite a few years now. I wonder why.
  8. That was interesting.

    One important point is that the heat would take time to build up from such a process.

    In spite of all the Earth's internal heat, it counts little for regional or global scale climate (directly), because the heat flux is very small. For internal heat to make a difference to surface temperatures on a large scale, the heat flux has to be significant compared to the heating by radiation from the planet's star. Assuming a rocky crust as on Earth, the thermal gradient must then be that much greater, which means perhaps a thin crust on a molten mantle.
  9. That last comment was about "'Dead' planets might be livable after all".

    hope to get back to AO discussion within a few days...
  10. Patrick
    Re: 108
    Maybe not global, I was thinking on a much more localized scale (as in the cause of El Nino) that has wide effects (as in El Nino).
  11. 2004 Indian Ocean Tsunami Biggest in 600 Years turns out to be more evidence of tectonic upset.
  12. Mystery Wave Strikes Maine Harbor By Robert Roy Britt, LiveScience Managing Editor, 04 November 2008: "A series of large, unexpected tsunami-like waves as high as 12 feet struck Maine's Boothbay Harbor on Oct. 28, and there's still no explanation for what caused them."
  13. "Mystery Wave Strikes Maine Harbor" - interesting, yes. Likely related to climate change, or a multidecadal scale geological variance - the later seems unlikely, the former could be true in the sense that this may happen more often due to storm waves or whatever, but considering the (apparently) sparse number of such events, it's hard to find a trend, so unless this kind of thing could be expected as a result of something else, there isn't much to go on.

    "2004 Indian Ocean Tsunami Biggest in 600 Years" - "turns out to be more evidence of tectonic upset." - it was a tectonic upset, but not the kind for which a correlation to multidecadal climate trends would be expected.

    On the Arctic Oscillation -
    "Synchronized Chaos: Mechanisms For Major Climate Shifts"
    - I will have to read the paper referenced by the article. I suspect though that more is understood about how CO2 would affect climate than is about these kinds of things.

    The other two: they suggested global warming could be behind the trend in the AO, or at least some portion of it. Of course there is internal variability, and some unforced variation in AO will occur. (?) AO itself doesn't seem to cause much of a global average temperature change (? - if the change in temperature at midlatitudes is balanced by that in the polar region).
  14. More on Tectonic activity and poor instruments:

    "On May 12, 2008, at 2:28 p.m., China's Szechwan province changed forever. In the space of 90 seconds, an earthquake equivalent to 1,200 H-bombs pulverized the earth's crust for more than 280 kilometers. Entire cities disappeared and eight million homes were swallowed up. This resulted in 70,000 deaths and 20,000 missing."
    "According to ShaoCheng this tragedy could have been avoided. "There hasn't been one earthquake in Szechwan province for 300 years. Chinese authorities thought the fault was dead," he says. The problem is that China relied on GPS data, which showed movements of 2 mm per year in certain areas when in reality the shifts were much bigger. "GPS is high-tech, but do we really know how to interpret its data?," he questions."

    Ref: Can China's Future Earthquakes Be Predicted? ScienceDaily (Nov. 24, 2008)
  15. This article Prehistoric Climate Can Help Forecast Future Changes ScienceDaily (Nov. 25, 2008, includes an interesting graphic. The "hot spot" anomalies in ocean temperatures are all very geologically active areas of volcanism/plate tectonics.
    While the article itself is worth reading, it's the illustration that stands out.
  16. John Cook said:
    “There are two skeptic approachs to volcanoes: high volcanic activity causes global warming and/or low volcanic activity causes global warming” - I say: “two skeptic approachs to volcanoes”, don’t excluded…

    „On the contrary, relatively frequent volcanic activity in the late 20th century may have masked some of the warming caused by CO2.” - I think - it’s not “all” right…

    1.In IV report IPCC, chapter 2, p. 194, is Fig. 2.18 - distinctly differ from John’s Fig whit volcanic - optical depth…
    2. In this IV report on p. 195-6 is writing about “chemical destruction of stratospheric ozone”.

    Here is, in references, one interesting position: Tabazadeh at al, 2002…
    I remind You, what Tabazadeh was said then - in 2002 y: "Both the 1982 El Chichon and 1991 Mt. Pinatubo eruptions were sulfur-rich [not only S, but else Cl2 ,B(OH)3,NH3,CH4, Cl, F by metals compounds] , producing volcanic clouds that lasted a number of years in the stratosphere," "A 'volcanic ozone hole' is likely to occur over the Arctic within the next 30 years, [!!!]" “Between about 15 and 25 kilometers (9 to 16 miles) in altitude, volcanic Arctic clouds could increase springtime ozone loss over the Arctic by as much as 70 percent, according to Drdla” ( and

    The annually production anthropogenic CFC = 750,000 T pure Cl, = one week by Mount Erebus productions…, at the all a World volcanoes, have a annually production 36,000,000 T Cl…

    Results about It , is visible here,
    and of stratosphere temperature in:,

    Robert A. Ashworth in papers: CFC Destruction of Ozone - Major Cause of Recent Global Warming! (2008; - all paper is very interesting) say: “The loss of ozone allowed more UV light to pass through the stratosphere at a sufficient rate to warm the lower troposphere plus 8-3/4" of the earth by 0.48 o C (1966 to 1998).”

    IPCC said: global anthropogenic GHG effects in this period = ~ 0,5 dg. C,
    Ashworth said: “anthropogenic emissions of chlorofluorocarbons”, it’s the reason it…

    …I say: volcanic S, Cl, F - emissions, dear Mrs. Ashworth…

    I propose else this image: It’s worth seeing.
  17. Arkadiusz Semczyszak -

    "The annually production anthropogenic CFC = 750,000 T pure Cl, = one week by Mount Erebus productions…, at the all a World volcanoes, have a annually production 36,000,000 T Cl"

    CFCs are generally very unreactive until they reach the stratosphere and are broken down by UV, releasing Cl, etc. Volcanic Cl is probably much more reactive, and more likely to be rained out before reaching the stratosphere.

    I don't have time to read those papers right now, but I'll just note that the stratospheric cooling associated with AGW, (and also polar stratospheric cooling associated with increasing AO, which may or may not be a seperate matter, depending...) will make polar ozone holes more likely to result from any given ozone-depleting emission. Ozone depletion itself, while warming the troposphere below, cools the stratosphere by reduced UV absorption there, and also lets more longwave radiation from the surface escape to space, reducing any tropospheric warming that would result.
  18. A few of the problems with this:

    1. (at least one of) the IPCC figures are incorrectly interpreted - tropospheric ozone is increasing, NOT decreasing - this is also an anthropogenic effect.

    2. some temperature graphs are off.

    3. CO2 graph is off (though not as far off as another one I've seen).

    4. The evidence really does justify a conclusion that significant CO2 increases cause significant global (tropospheric and surface) warming.
  19. "
    “The loss of ozone allowed more UV light to pass through the stratosphere at a sufficient rate to warm the lower troposphere plus 8-3/4" of the earth by 0.48 o C (1966 to 1998).”

    Now spread that heat out over the top 100 m of ocean and see what happens.

    100 m * 70 % of area + 10/4 m** / (8.75 in* 2.54 cm/in + 10/4 m** (**water depth equivalent to atmospheric heat capacity)) =
    72.5 m / 2.72225 m = 26.6

    0.48 deg C / 26.6 = 0.018 deg C. But the quote refers to the lower troposphere, in which case the result is less; if the lower troposphere is the air below about the 500 mb level, for example, then I get 0.48 deg C/ 48.4 = 0.0099 deg C.
  20. Patrick
    I do see what you are saying but is it in fact catastrophic or just minor warming?

    Click Here for a recent article at Live Science : Earth's Atmosphere "Breathes" More Rapidly Than Thought
    By Andrea Thompson, Senior Writer, 2008-12-16
    "Earth’s atmosphere was known to "breathe" in a cycle lasting nearly a month. Now scientists say the planet takes a quick breath every few days."
  21. Concerning the breathing of the Atmosphere - (mostly the Magnetosphere)

    If there is a significant impact on surface+tropospheric climate, it would have to be either 1. changes in magnetosphere, ionosphere, or sun itself directly causing changes in radiative forcing via a supposed change in albedo such as by cloud particle nuclei or clear air transmissivity changes ... (how much of that happens and is there any multidecadal trend?) 2. via interaction with the E-region dynamo, driving circulation changes in the ionosphere, which somehow changes circulation in lower layers, perhaps in the way the stratospheric conditions affect the EP flux from waves in the troposphere ... (how much EP flux is way up there and what does it do? ? ?)

    Because the ionosphere and magnetospere are extremely thin, just too optically thin (except at shortest wavelengths - UV, etc.) to have significant direct effect on the overall energy budget of the atmosphere by changes in infrared radiation.
  22. ...(And the amount of energy in those shortest wavelengths is a very small fraction of the total radiant energy flux up or down)
  23. Patrick
    My point from the very befinning is that the atmosphere does not play as large a role in temperature as the IPCC and the alarmists claim. Every new article I read only confirms that our models are wrong. They just figured out, after 30 years of AGW hype, that the NE part of the US (and eastern Canada) has not warmed and in fact has gotten colder while the west coast warmed.
    I have come to the conclusion that it's the west coast alarmists hot air that caused the warming effect in the first place. :)
  24. "They just figured out, after 30 years of AGW hype, that the NE part of the US (and eastern Canada) has not warmed and in fact has gotten colder while the west coast warmed."

    And the interior of the continent?

    And Europe?

    And Asia?

    And Africa?

    And South America?

    And Australia?

    And Antarctica?

    And the oceans?

    And the glaciers? The tropical mountain glaciers?

    And the forests, and the birds, and the plants?...
  25. Patrick
    You may recall that when we started talking about Bertha we took note that tropical storms had been forming farther east, meaning a change in air currents.

    Eastern Canada and the N.E. U,S, are not the only places on earth that have cooled while population centers warmed and it is from population centers that most data comes from. Why was this cooling ignored?

    South America, Antarctica and Africa have not experienced the same changes as Europe and PARTS of Asia. In fact, it has been noted that most warming has been on the western coasts of the Americas and Europe.

    If you check the ocean threads here you will see that overall the oceans have not warmed but there ate definate warm currents and hot spots. South Atlantic and Antarctic deep water is notably getting colder.

    Referring to this as "climate change" is quite accurate, but it is by no means "global warming".
  26. ps
    Glaciers in sunny california are GROWING because of the extra moisture off the Pacific.

    I have posted links to all of these articles that describe what I have said. All of this climate change can easily be explained without super powerful CO2 forcing that historically does not seem to very powerful at all.
  27. Also you might want to read Peter Ward's work on the PT extinction (not the media coverage that assume CO2). While Ward does not recognize the importance of the Antarctic impact, he does cite the Siberian Traps that it created as releasing METHANE and poisionous gas. While the gas may have caused a GH condition, the GHG did not cause the extinction event, which (as he points out in Gorgon and elsewhere) was a two stage extinction. First the oceans died (90% of all ocean species) and was followed by land species (70%). What most forget when reading about the PT extinction is that the Pennsylvanian-Permian Ice Age had just closed and the planet had warmed (naturally) prior to the extinction event, just like right now after 12000 years of interglacial (the average length of an interglacial BTW).
  28. Here's the thing(s) about that:

    Eastern Canada and the N.E. U,S, are not the only places on earth that have cooled while population centers warmed and it is from population centers that most data comes from. Why was this cooling ignored?

    No, not really. The Arctic has warmed, the oceans have warmed (Aside from other data, sea level has been rising - that has to be mainly a combination of melting or temperature inceases - melting involves some of the heating occuring without temperature changes, of course).

    "South America, Antarctica and Africa have not experienced the same changes as Europe and PARTS of Asia. " ... " South Atlantic and Antarctic deep water is notably getting colder."

    The point being, you have to put all those together. It's still global warming, in the sense that there is more heat coming in then going back into space.

    "Glaciers in sunny california are GROWING because of the extra moisture off the Pacific."

    And why is that happening?

    "All of this climate change can easily be explained without super powerful CO2 forcing that historically does not seem to very powerful at all."

    It could be explained without CO2, but with strain and guessing. Much or most can be explained very very very very very very very very easily with a net forcing that is the sum of contributions from the changes in CO2, somewhat smaller from the rest of GHGs, a sizable likely negative aerosol contribution, rather small contributions from episodic volcanoes and solar radiation, and also, some other effects of ozone depletion (that doesn't explain the general global warming, etc, but it has effects). Etc.
  29. Sea level rise is within the Fairbridge curve; ie. normal or "expected". The Arctic is the obvious problem which is why I did not mention it. But outside of Greenland it won't cause a rise in sealevel because it is expanded (frozen) water that is also displacing sea water at present. Add to that the increased sea and glacial ice in Antarctica despite the small area near S.A. and there is no reason for additional sea level rise. The planet went through a brief warm spell, a large part caused by ocean cycles but some was abnormal. The anomally clearly shows which areas and they are decidely not global.
    I like the way you calculate out the CO2 forcing but I still agree with Spencer. There is a fundamental flaw somewhere. Be the one to find it.
  30. Regarding the P/T extinction:

    The concept as I understood it:

    There was a long ice-house period (with some significant ice, sometimes more (ice ages)) in the late Paleozoic. I've not been clear just when that ended, whether that was part of the P/T extinction or not. If it had ended but only just recently, that might have left species more vulnerable to any further warming.

    It was a time of continental collision - the formation of Pangea.

    One version:

    So then this Siberian trap flood volcanism starts up and persists for ~ a million years (more?), pumping CO2 into the air at a faster than typical rate. (Aerosols too, but those don't accumulate.) Eventually there is a lot more CO2. The Earth warms - maybe 5 degrees C - some extinctions occur (more on land??)

    The warmth causes CH4 release from the oceans. Sudden burst of warming. A total of 10 deg C more than before the flood volcanism? More extinctions.

    Oxygen doesn't dissolve as well in the oceans because of higher temperatures. Anaerobic bacteria that produce H2S become more commonplace. H2S in oceans, maybe some in the air. More extinctions.
  31. "the average length of an interglacial BTW"

    Average, perhaps. Not all. Once every few interglacials, one is longer - although this is too long of a pattern to have been repeated much in the last several hundred thousand years, but there was at least one extra-long interglacial. Based on astronomical forcings, this interglacial could be one of the extra-long ones, perhaps lasting another 20,000, 30,000, or 50,000 years, even without AGW.

    "t won't cause a rise in sealevel because it is expanded (frozen) water that is also displacing sea water at present. "

    Yes, of course. Yet, the sea level is rising; Greenland is losing land-based ice (potential point of confusion: the base of the ice is below sea level in many parts, and in Antarctica too (West Antarctica in particular), but the height of the surface of the ice is such that most of the weight of the ice is not supported by the water - it will raise sea level when it melts). Antarctica may also be losing ice in total even though some parts may be gaining ice mass.

    "Sea level rise is within the Fairbridge curve; ie. normal or "expected"."

    But if it is expected, what is the expectation based on? (Fairbridge's argument about Solar jerk was based on cycles dominated by Jupiter and Saturn, but the actual forces (tides on the sun) would be dominated by Jupiter and Venus, then Earth and Mercury, before any other gas giants - and I showed earlier these would be exceedingly exceedingly small effects.) I'm really not at all convinced that the Fairbridge curve was/is based on a solid body of evidence.

    "I like the way you calculate out the CO2 forcing"

    Thank you - but actually, I only explained how it is calculated, and the physical principles on which it is based, which are as sound as the inverse square law.

    "but I still agree with Spencer."

    Spencer doesn't really make a durable point, though.
  32. In that work of Spencer we've discussed, his argument was not abotu CO2 forcing but about climate sensitivity.

    There is no flaw in the fundamental sense. There is uncertainty. Spencer's argument seemed ill-concieved to me - the logic isn't quite there.
  33. Spencers argument is specifically about sensitivity to CO2. Look under Arguments, the Pacific Decadal Oscillation (at this site). I posted a link to a draft he did that they have refused to publish. I would prefer to be wrong about all this as I much prefer a warmer world but I fear that Spencer may be right. I am sure that Fairbridge was as the last two winters have been showing. The test is 2007 through 2011. Halfway there.
  34. ps
    This is spencers site. Articles and links to peer reviewed papers.
  35. Sorry, I missed something that you said. The Fairbridge curve and the Solar Jerk are two different hypotheses. The curve was rejected and is now accepted by the consensus while the solar jerk still has not been accepted. They are unrelated subjects.
  36. The problems I saw in Spencer's approach:

    1. he was looking at climate sensitivity based on Temperature and radiative fluxes (top of atmosphere (TOA)) over rather short time periods. This is not an equilibrium climate sensitivity at all.

    (PS if a period of 5 years is sufficient, then why isn't 40 or 100 years of warming sufficient?)

    2. conceivably there could be some net global cloud feedback, as well as the ice-albedo and and water vapor feedbacks and others, to forcing of climate from CO2, etc.

    Over short time periods (this is part of concern 1, actually), any water vapor feedback and other feedbacks, etc., would be limited by thermal inertia of the oceans. In addition, CO2 would generally only be a feedback over longer time periods.

    What is the cloud feedback to cloud forcing? 'Internal Radiative Forcing' is a feedback to some other internal effect, and will react to itself...

    3. If one of the graphs could be shown in enough detail, one might judge to what extent temperature fluctuations are driving radiative fluctuations and vice-versa - obviously both happen - they must, that's the physics.

    4. On that note, there can be some correlation, perhaps with some lag in time or not, between cloud radiative feedback and temperature, or temperature changes, that is not entirely due to a direct forcing of temperature by clouds OR a direct forcing of clouds by temperature.

    The short term variability may involve fluctuations in cloud type, amount, and distribution, and in temperature and wind, etc, that are of a different nature than that of longer term changes.

    Spencer's description of how the IPCC, etc, estimate sensitivity is not descriptive enough for me to judge what it means.



    "And it appears that the reason why most climate models are instead VERY sensitive is due to the illusion of a sensitive climate system that can arise when one is not careful about the physical interpretation of how clouds operate in terms of cause and effect (forcing and feedback)."

    This seems to set aside any work that goes into trying to realistically model clouds based on observations of clouds and weather on smaller spatial scales (relative to global) - I think 'they' do that.

    The allure of models is strong: they are clean, with well-defined equations and mathematical precision. Observations of the real climate system are dirty, incomplete, and prone to measurement error.

    Well, I guess we should trust the models, then, eh Spencer? :) (I just found that particular passage to be very ironic, and not just within the context of this paper.)
  37. 3 and 4 in last comment -

    What I mean - Spencer refers to striations and spirals. Are those spirals predominantly clockwise or counterclockwise? (And does it vary by the size of the spiral? Etc...)

    It may be that the method for figuring out climate sensitivity that Spencer is criticizing is actually not a very good method, for perhaps some of the same reasons that Spencer's own method seems lacking. But this is just one piece of the puzzle (which might have been helpful but unnecessary? - There is a lot of other evidence out there).

    For example, Spencer mentions use of this method on climate models. But the most clear cut way to evaluate climate model sensitivity is to have multiple runs in response to various forcings and compare.


    "The curve was rejected and is now accepted by the consensus"

    Could you show me where it is accepted?
  38. It also occurs to me that Spencer's analysis could be capturing some aspect of the annual cycle.
  39. Patrick

    Wikipedia Entry


    A quick web search provides many more links.
  40. ps
    Here is another example from a different scientist. There is an apparent agreement with Fairbridge:

    Earth's Orbit Creates More Than A Leap Year: Orbital Behaviors Also Drive Climate Changes, Ice Ages
    ScienceDaily (Feb. 18, 2008) — The Earth's orbital behaviors are responsible for more than just presenting us with a leap year every four years. According to Michael E. Wysession, Ph.D., associate professor of earth and planetary sciences in Arts & Sciences at Washington University in St. Louis, parameters such as planetary gravitational attractions, the Earth's elliptical orbit around the sun and the degree of tilt of our planet's axis with respect to its path around the sun, have implications for climate change and the advent of ice ages.
  41. "Earth's Orbit Creates More Than A Leap Year: Orbital Behaviors Also Drive Climate Changes, Ice Ages
    ScienceDaily (Feb. 18, 2008)"

    That's just the Milankovitch cycles. It's basic grade-school science. Nothing new here.

    "There is an apparent agreement with Fairbridge"

    Well, according to "Article" from comment 139, Fairbridge was an early supporter of the Milankovitch cycle-driven climate changes concept. But that doesn't do anything to bolster his other concepts about solar jerk and sizable sudden sea level changes in the later Holocene.

    Also, "Article" did imply that the Fairbridge curve had been accepted in some way, but I don't buy that in full. Of course I wouldn't be surprised if sea level changes have some irregularity or even smaller cycles in them; there's no rule about having to rise completely monotonically (never reversing) between the peak of the last ice age and the present. But that's different then accepting the Fairbridge curve.
  42. Re: "That's just the Milankovitch cycles."
    Not Quite. It's a better understanding of various cycles, not just Milankovitch.
  43. Re: "It also occurs to me that Spencer's analysis could be capturing some aspect of the annual cycle."
    Climate is the average of annual cycles over a given time period. The 30 year limitation currently used skews the results.
  44. Re 143:
    1. In the work of Spencer we had been discussing, he was using observations over short time periods - not long term climate trends - to attempt to infer the magnitude of climate sensitivity. Some portion of that short term variation occurs in under a year. Because of asymmetries between the hemispheres and also that fall and spring are not just the averages of winter and summer, etc, there will be some annual cycles in some global averages, which result from external forcing but of course involve feedbacks.

    Spencer also tried to explain most of recent global average surface temperature trends in terms of the PDO and ENSO, I think (it was a strain to do so - in other words, Occam's razor selects against this explanation). There may be an irony there - what positive feedbacks are available to boost internal variability while leaving external forcing so impotent? Of course, there are different spatial-temporal structures in different feedbacks to different things, etc...

    The 30 year limitation - what limitation, exactly? The satellite data and some other data may only go back to x, but where it agrees with other data we might gain confidence in other data sets going back further; also we have paleoclimate and paleoclimate forcing records, and physics and modeling to fill in some of the blanks.

    Re 142:
    Where in the article did you see something besides Milankovitch cycles?
  45. Patrick
    "Re 142: Where in the article did you see something besides Milankovitch cycles?"

    Here: "According to Michael E. Wysession, Ph.D., associate professor of earth and planetary sciences in Arts & Sciences at Washington University in St. Louis, parameters such as planetary gravitational attractions,"

    You see "planetary gravitational attractions" are an addition, referring to what I am talking about and not part of the Milankovitch cycle theory.
  46. Re: "Spencer also tried to explain most of recent global average surface temperature trends in terms of the PDO and ENSO,"

    Yes, but he does not get into the cause of the PDO or ENSO as I have (granted it's only my hypothesis, it does lend support to it).
  47. "You see "planetary gravitational attractions" are an addition, referring to what I am talking about and not part of the Milankovitch cycle theory. "

    Those gravitational attractions are responsible for the Milanovitch cycles - precession of tilt and perihelion advance, changes in tilt, changes in eccentricity of orbit; also, changes in the plane of the ecliptic, though whether that has any significance climatologically is ... ? - but that's still a 70,000 year cycle. None of these cycles is shorter than ~ 20,000 years.

    If shorter-term astronomical cycles were meant to be implied to 1. exist (of course some do - but are there more than either of us is familiar with? The Chandler wobble (~over 400 days, no significant climatological consequence), cycles in the moon's orbit (perigee advance? (~between 8 and 9 years), precession of nodes (precession of tilt of the orbital plane relative to Earth's orbital plane) ~ between 18 and 19 years, some other shorter cycle(s) - these and consequent alignments with Earth-sun orbital geometry (including) perhelion/perigee alignment; solar cycles (of course they affect climate, but seem to only account for some fraction of recent warming, not-so-large a fraction especially in more recent decades) ...

    Of course, the Milankovitch cycles result from tidal torques on the Earth's equatorial bulge (mostly from the moon and sun) and tides acting on the Earth's orbit (the difference in the gravitational acceleration due to other planets acting on the Earth-moon system relative to the sun) - with some relativistic contributions, about which I don't know much.

    These are cummulative effects, I think, considering that the tidal torque on the equatorial bulge must go through semimonthly (no torque from moon when aligned with equatorial plane, which it crosses roughly twice in a full orbit) and semiannual cycles (no torque due to sun at equinoxes). There are obviously cycles in the alignments of the planets, and modulated by relative positions of perihelions and ascending nodes (the ascending node is where an object's orbit crosses a reference plane from south to north - typically the reference plane for planets is the ecliptic - approx. the plane of the Earth's orbit. One might also use the "invariable plane" of the solar system - the total angular momentum vector of the whole solar system is perpendicular to this plane).

    Anyway, Milankovitch cycles, I think, result over time as cummulative effects from forces that are also cycled over time over shorter periods.

    Are there significant cycling displacements in such things as tilt (magnitude and/or direction) and Earth-sun distance that occur in shorter time periods (that don't average to near zero over just a few years but can be set aside over thousands of years leaving the Milankovitch cycles)?

    If there were, I would have expected to here more about it in an article where "planetary gravitational attractions" were being highlighted.

    The impression I've gotten is that these short-term pulsations are small relative to the trend over 1000s of years. That is, using snow-depth as an analogy to tilt, eccentricity, etc, the impression I've gotten is that we get to ~ 1000 inches over 1000s of years by many small flurries that occur every month or so, a few bigger than the rest, but without much melt in between - as opposed to massive snowstorms followed by heatwaves.
  48. Patrick
    Re: 147
    Fairbridge and his idea of Jupiter and other planets affecting the Barycenter, effecting solar activity, affecting climate.

    Remeber we discussed water levels before?

    I found this article (don't know how I missed it).

    World On Water
    "Geophysicists Show That Crust Temperature Variation Explains Half Of Elevation Differences In North America"
    February 1, 2008 — Geophysicists determined that tectonic mountain-building processes are not the only factor that determines elevation in North America. The temperature of the crust affects its density, and lower density crust will rise higher than colder, higher density crust. The heat in question comes from the Earthýs interior and also radioactive decay of various elements in the crust. Broadly, the Rocky Mountain region of the United States has the hottest crust, as well as the highest general elevation.

    Interesting no?
  49. This is where the volcanos are active in Antarctica
    Funny coincidence?

    Nice map.

    Are these all active right now? When was the last time they were active? Is the activity unusual for the last 1000+ years?

    "Geophysicists Show That Crust Temperature Variation Explains Half Of Elevation Differences In North America"

    Yes, that's interesting. If we were discussing changes over millions of years, it could potentially pertain.

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