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The Volcano Gambit

Anyone reading pundits and politicians pontificating profusely about climate or environmental science will, at some point, have come across the “volcano gambit”. During the discussion they will make a claim that volcanoes (or even a single volcano) produce many times more pollutant emissions than human activities. Often the factor is extremely precise to help give an illusion of science-iness and, remarkably, almost any pollutant can be referenced. This “volcano gambit” is an infallible sign that indicates the author is clueless about climate science, but few are aware of its long and interesting history…

From Augustine to Mt. St. Helens

The ur-usage was a legitimate paper in Science in July 1980 by seismologist David Johnston writing about chlorine emissions in eruptions:

Earlier estimates of the chlorine emission from volcanoes, based upon evaluations of the pre-eruption magmatic chlorine content, are too low for some explosive volcanoes by a factor of 20 to 40 or more. Degassing of ash erupted during 1976 by Augustine Volcano in Alaska released 525 x 106 kg of chlorine (±40%), of which 82 x 106 to 175 x 106 kg may have been ejected into the stratosphere as hydrogen chloride [HCl]. This stratospheric contribution is equivalent to 17 to 36% of the 1975 world industrial production of chlorine in fluorocarbons.

In the main text, there was also this quote:

[The] eruption of the Bishop Tuff from Long Valley Caldera, California, 700,000 years ago generated 100 km3 of air-fall ash(19). If the magma degassed 0.25% chlorine (equivalent to Augustine Volcano), this eruption may have injected 289 x 109 kg of HCl into the stratosphere, equivalent to about 570 times the 1975 world industrial production of chlorine in fluorocarbons.

For context, a big issue at the time was to characterise the budget for chlorine in the stratosphere, given it’s importance in ozone depletion. While there is quite a lot of HCl emitted by volcanoes, that form of chlorine is soluble, and is swiftly rained out, unlike the much less reactive human-made chlorofluorocarbons (CFCs) which can stay in the atmosphere from many decades. Multiple studies subsequent to the Johnston paper confirmed that the volcanic contribution to stratospheric chlorine is actually very small, but this paper was a genuine attempt to constrain this term. To summarise, there are two cases mentioned, Augustine (in Alaska, 1976) and the Long Valley Caldera (California, 700,000 yrs ago), with estimated multiples of 0.17-0.36 and 570 of HCl injection into the stratosphere compared to the annual industrial source of Cl in CFCs. [Note – if anyone has an earlier usage, please let me know].

An important volcanic event in 1980 was of course the huge eruption of Mount St Helens in May of that year. Tragically, the author of the Science paper, David Johnston, an up-and-coming USGS volcanologist, was himself killed in the blast a couple of months before his paper appeared.

Later that year, in October, Ronald Reagan commented on the eruption, suggesting that “one little mountain out there [Mt. St. Helens], in these last several months, has probably released more sulfur dioxide into the atmosphere than has been released in the last ten years of automobile driving or things of that kind.” However, while the volcano emitted roughly 2×106 metric tons SO2, annual emissions from cars were 30 x 106 tons (out of a total human emission of ~131×106 tons). Reagan was out by a factor of 150. This was just the beginning of the mangling.

More relevant for the growth of the volcano gambit, these results got more and more warped in subsequent retellings. For instance, in 1990, Dixy Lee Ray, the ex-marine biologist and former (Democratic) governor of Washington, wrote in her book: “The eruption of Mt. St. Augustine in 1976 injected 289 billion kilograms of hydrochloric acid directly into the stratosphere. That amount is 570 times the total world production of chlorine and fluorocarbon compounds in the year 1975…. So much is known.” She mixed up the huge eruption 700,000 years ago, with a much smaller one in 1976, but it would get worse.

The Johnston paper also became a staple of the folks engaged in rearguard defenses against the 1989 Montreal Protocol, in particular, the Maduro and Schauerhammer book “Holes in the Ozone Scare” quotes the paper accurately, but ignores subsequent work ruling out the HCl source for stratospheric chlorine. This was well discussed by Sherwood Rowland in a 1993 Science commentary which aptly enough was focused on the need for better scientific communication with the public.

… to Mt. Pinatubo

In June 1991, Mt. Pinatubo in the Philippines erupted, and unsurprisingly became the volcano of choice for the contrarians.

Rush Limbaugh discussed this at various points in 1992 and in his 1993 book. On Nightline he stated: “it is man-made products which are causing the ozone depletion, yet Mount Pinatubo has put 570 times the amount of chlorine into the atmosphere in one eruption than all of man-made chlorofluorocarbons in one year”. (Note the further confusion attributing the eruption 700,000 yrs to the one that just happened). In his book “The Way Things Ought To Be” (1993) Limbaugh stretched the facts still further: “Mount Pinatubo in the Philippines spewed forth more than a thousand times the amount of ozone-depleting chemical in one eruption than all the fluorocarbons manufactured by wicked, diabolical, and insensitive corporations in history.” He claims he got this information from Dixy Lee Ray’s book, “the most footnoted, documented book I have ever read.” Which, as noted above was already garbled. (More discussion on Limbaugh’s errors here and here).

From Chlorine to Greenhouse Gases

The Dixy Lee Ray book turns out to be a major source for disinformation, though with little evidence anyone read it carefully or looked up the references. In 2004, the conservative commentator, Jude Wannski mis-remembered Dixy Lee Ray: “[the] book she wrote, Trashing the Planet … debunked a number of myths about the environment. In it she had the following line: “The eruption of Mt. St. Helens in 1980 dumped more greenhouse gases into the atmosphere than all that has been released since the industrial revolution. Volcanoes have been erupting for millions of years with the same result. If this really affected climate, don’t you think it would have happened by now?””. This swaps HCl for greenhouse gases, conflates Mt St. Helens with St Augustine in her text (which in any case should have been the Long Valley Caldera)…

As environmental concern moved to the impact of global warming on ice sheets, so disinformers moved the volcanoes accordingly. In 2006, Christopher Monckton (“the Potty Peer”) said “In a good year for eruptions, Erebus can put out as much CFCs as Man used to.”

A year later (2007), Martin Durkin in his execrable documentary claimed that “One volcanic eruption for example, puts more pollution into the atmosphere than ten years worth of human activity.” This, despite being totally unspecific (which pollutant does he think he is referring to?), is of course wrong in any case. Perhaps he was channeling Reagan?

As in 1992, a new eruption gave rise to a new eruption of the gambit. In 2009, the “Stop Global Cooling” crowd stated: “Sure, volcanoes like the one spouting off in Alaska right now spew much more CO2 than humans could ever think of”. Similarly, Congressman Dana Rohrabacher in March of that year added: “Can one huge volcano spew more CO2 into the atmosphere than all the people? Yes”. Ummm… no.

And yet it goes on. Ian Plimer in another contrarian tome included some even more made up facts: “massive volcanic eruptions (e.g. Pinatubo) emit the equivalent of a years’ human CO2 emissions in a few days” (p472) and “Volcanoes produce more CO2 then the world’s cars and industries combined” (p413). On p217 he claims that while “Mt. Pinatubo . . . released 20 millions tonnes of sulphur dioxide” it also released “very large quantities of chlorofluorocarbons”, citing Brasseur and Granier (1992) who don’t say there were any CFCs in the eruption, and even on chlorine, actually say the opposite: “after the eruption of Mount Pinatubo, the input of chlorine to the stratosphere was probably small”.

From Pinatubo to Eyjafjallajökull

In 2013, it was the turn of Eyjafjallajökull in Iceland to steal the limelight. Ex-Gov. Mike Huckabee said: “The volcano that erupted over in Northern Europe actually poured more CO2 into the air in that single act of nature than all of humans have in something like the past 100 years.“. Senator Lisa Murkowski in 2014 similarly mentioned a volcano she “had heard about” in Iceland. “The emissions that are being put in the air by that volcano are a thousand years’ worth of emissions that would come from all of the vehicles, all of the manufacturing in Europe,” she said. Huckabee was using the same point as recently as July 2015: “a volcano, in one blast, will contribute more [CO2] than 100 years of human activity“. A century or a millennium – who’s counting?

Again this is all patent nonsense – the amount of CO2 emitted by Eyjafjallajökull was in fact more than 20 times smaller than just European aviation emissions per day – and the claim was rightly debunked by, Slate, and HuffPo at the time.


So let’s recap with a simple graphic charting the use and abuse of these claims, colour-coded by the degree of wrongness:

To summarise, a speculative paper (that was later contradicted) about HCl emitted in a volcano 700,000 years ago is the progenitor of statements related to SO2, CO2, greenhouse gases or just “pollutants” in general, and has been associated with Mt. Augustine, Mt. St. Helens, Mt. Pinatubo, Erebus and Eyjafjallajökull, with comparisons to all industrial emissions in a year, 100 years, or since the industrial revolution, all cars in a decade, or indeed a thousand years.

The volcano gambit is the universal comparison, untethered to any actual facts, and look for it to resurface again the next time a big volcano hits the news.


  1. D.A. JOHNSTON, "Volcanic Contribution of Chlorine to the Stratosphere: More Significant to Ozone Than Previously Estimated?", Science, vol. 209, pp. 491-493, 1980.
  2. F.S. Rowland, "President's Lecture: The Need for Scientific Communication with the Public", Science, vol. 260, pp. 1571-1576, 1993.
  3. G. Brasseur, and C. Granier, "Mount Pinatubo Aerosols, Chlorofluorocarbons, and Ozone Depletion", Science, vol. 257, pp. 1239-1242, 1992.

122 Responses to “The Volcano Gambit”

  1. 51
    JBL says:

    No one else has said it, so let me note that “pundits and politicians pontificating profusely” was a nice touch.

    [Response: Thanks! – gavin]

  2. 52
    JBL says:

    #24, Gary Herstein: I have trouble that anyone has ever been convinced of anything by the strategy you are suggesting, except perhaps that their interlocutor is an unpleasant person with whom to discuss controversial topics.

  3. 53
    Aaron Sheldon says:

    Ah, the old volcano comparison, I once took a stab at that.

    If you work out the numbers, since the start of industrial revolution in 1750 humans have released the equivalent CO2 of only 1 Mount Pinatubo 1991 eruption…in every nation…in every year…since 1750.

    Or put another way we have short circuited a tens of millions of years long carbon cycle down to a couple of centuries.

  4. 54

    RM @42,

    The greenhouse effect definitely exists, since without it the Earth would be frozen over, a point first made by Fourier in 1824. Global warming refers to a change in the level of the greenhouse effect (more of it). You’re wrong about that, too, since mountains of evidence now show global warming. Please familiarize yourself with the evidence.

  5. 55
    Hank Roberts says:

    > Barton Paul Levenson … Watt’s Up With That? REALLY?

    Not. When Russell appears to do that, focus on the beginning of the link: “vee vee” not “doubleyou”

  6. 56
    Jim Eager says:

    Rick Mendham @42, I’m afraid you are going to have to do much, much better than offer up a few unsupported assertions, personal incredulity, and completely unrelated misstatements of fact if you want to be considered a serious Climate Ball player.

  7. 57
    Mal Adapted says:

    Barton, take a closer look at Russell’s URL, especially the first character.

  8. 58
    Francisco Colmenares says:

    Unimportant but this caught my eye:

    Later that year, in October, President Reagan commented on the eruption

    Shouldn’t that be, Presidential Candidate Reagan? The elections were in November and Reagan officially became the President on January 20th, 1981.

    [Response: Absolutely correct. Thanks. I’ve edited to remove that premature designation. – gavin]

  9. 59
    Russell says:

    You’re referring me to a page by Watt’s Up With That? REALLY?
    Comment by Barton Paul Levenson

    No, Barton- I’m referring you to articles from Nature, Foreign Affairs, The National Interest and JGR

    And Sou’s Hot VVhopper featuring Roast Willard Tony isn’t a cannibal fast food blog, either.

  10. 60

    R: And Sou’s Hot VVhopper featuring Roast Willard Tony isn’t a cannibal fast food blog, either.

    BPL: Well, it should be!

  11. 61
    patrick says:

    #44 BPL: Don’t worry, it’s a just another distraction, however you regard it. Plus it’s too derivative to appeal to the originality of your own mind, I think.

  12. 62
    patrick says:

    As someone who has heard R. Limbaugh harp at length,”Yes, ladies and gentlemen, nature is more ffiiiIIIIthyy than man,” on the subject of volcanoes, I am grateful for the fine forensic analysis and insight into echo-chamber dynamics provided here.

    It remains a contradiction to me that a lot of groups whose ethical constructs happily sell salvation by appeal to the countless culpabilities of unregenerate humanity are at pains to distort and deny human agency in the case climate change.

  13. 63
    Hank Roberts says:

    Well, I suppose if tactical nuclear weapons had remained on the table, and testing proceeded apace we’d have them pocket sized and set out as tripwires all over Europe by now. Instead of the few varied conventional forces we’re now dropping into Putin’s way.

    But as I recall the distance between cities in Germany is approximately one kiloton, so that might still not have been small enough to properly serve to protect the area and discourage Russian tanks from despoiling the countryside on their way to Syria.

    Or whatever scenario would have played out if nuclear winter/fall/cold-snap hadn’t discouraged further development.

    But I’ve always doubted that nuclear winter really was the critical factor — I recall quite clearly that both the US and the USSR rather hurriedly did nuclear tests at the edge of space, with the notion that they could throw enough of those fast enough to knock down some of an incoming missile flight.
    And instead, they knocked out their own electrical grids, to everyone’s consternation. The test ban treaty came quite soon thereafter.

    I mean, people (those in power) could survive a few cold years. But they probably didn’t feel as confident about surviving five or ten years without electricity or telephones or prompt delivery of sunscreen to their undisclosed locations.

    Just speculating.

    But there’s almost a point — which is that often enough the problem you’re most concerned or fearful of isn’t actually the worst problem you’re going to have to deal with, and the policy people may be trying to twist things around to deal with something they haven’t even let the public know about yet.

    My bet’s on viral contagious hereditary stupidity as the next big thing.

  14. 64
    Russell says:

    60 : Try to stay off the menu, Barton, Willard’s sidekick Willis has a wide acquaintance in the Solomon Islands.

  15. 65
    Paul Donahue says:


    I love the graphic! Can you provide a copy with resolution suitable for printing and posting in my office?

    Paul D.

  16. 66
    Nick Gotts says:

    Excellent article!

    “Although higher education raises the odds of an accurate answer, political identity turns out to be a stronger predictor by far. Odds of responding “volcanoes more” instead of “humans more” are almost 8 times higher among Tea Party supporters than among Democrats of similar age, education and gender.” – L. Hamilton@10

    Yes, reality has a pronounced left-wing bias!

  17. 67
    t marvell says:

    The sleazy right comes up with a lot of arguments why AGW is not important, e.g. cosmic rays. It’s wack-a-mole. A variation on an old propaganda trick: if you say enough lies, people might believe some.

  18. 68
  19. 69
    Edward Greisch says:

    63 Hank Roberts:
    discourage Russian tanks: SADARM does that, if I remember the name correctly.

    hadn’t discouraged further development: Development continues because the bombs get stale.

    nuclear tests at the edge of space: You have confused Starfish Prime, which was about EMP, with the 1970s ABMs, Spartan and Sprint. Spartan and Sprint are long since dead, killed by the increasing accuracy of our new ABMs. Our new ABMs are fired from Aegis cruisers and destroyers. Star Wars, the Navy version, works. We can shoot down ICBMs.

    The really serious problems are GW, overpopulation and resource depletion.

    There has always been plenty of hereditary stupidity.

  20. 70

    EG @69: Our new ABMs are fired from Aegis cruisers and destroyers. Star Wars, the Navy version, works. We can shoot down ICBMs.

    BPL: I may be wrong, but I thought the antimissile missiles on Navy ships were to shoot down shore-to-ship or air-to-ship missiles, not ICBMs.

  21. 71
    Edward Greisch says:

    70 Bart: You are thinking of the automated gatling guns called Phalanx.

  22. 72
    Racetrack Playa says:

    It’s really too bad about all the misinformation, but that is a great graphic. In reality, Pinatubo and other major volcanoes have served as good validation of climate models, since the climate responses to Pinatubo (such as the water vapor feedback) were correctly predicted, as seen in this comparison of models and observations post-Pinatubo:

  23. 73
    Thomas says:

    please excuse off-topic but this deserves a retort.
    69 Edward Greisch says “We can shoot down ICBMs.”
    Um, so can Russia, China and Iran et al – short or long range BMs.

    BPL: I may be wrong, but I thought the antimissile missiles on Navy ships were to shoot down shore-to-ship or air-to-ship missiles, not ICBMs.

    I think you’re right. There’s the flip side that Russia (and therefore China) can block the Aegis system making them blind and unable to fire antimissile missiles – but I may be wrong (it’s supposed to be a secret). Real events will prove that one way or another soon enough.

  24. 74
  25. 75
    Edward Greisch says:

    73 Thomas: Another arms race, this one in electronic warfare.

  26. 76
    Matthew Marler says:

    Thank you for the essay.

  27. 77
    Edward Greisch says:

    “Starfish Prime was a high-altitude nuclear test conducted by the United States on July 9, 1962,”

    “The Cuban Missile Crisis, also known as the October Crisis (Spanish: Crisis de octubre), the Caribbean Crisis (Russian: Карибский кризис, tr. Karibskiy krizis), or the Missile Scare, was a 13-day (October 16–28, 1962)”

    Starfish Prime was 5 months before the Cuban Missile crisis.

    Some of my early bosses, including Jere Dando, were there at Starfish Prime.

    This is off topic, so that is enough of this.

  28. 78
    AIC says:

    Are there literature citations for actual measurements of CO2 emissions from volcanoes? I didn’t see any references to such.

  29. 79
    AIC says:

    Literature citations for actual measurements of CO2 emissions from volcanoes?
    (not sure if my previous post went through)

  30. 80
    Hank Roberts says:

    > actual measurements of CO2 emissions from volcanoes?

    Scholar finds both measurements and estimates; many volcanos are yet to be instrumented, though.

    Not particularly relevant for climate because there’s no trend in vulcanism (detectable as earthquakes for that matter). Volcanic gases are background — not changing — barring something like the Deccan Traps eruption coming on, which would change things.

  31. 81
    patrick says:

    Looking to (find) kinds of things that really matter, re: CO2 and volcanic activity, following Frank Corsetti, 3 April 2016 in USC News:

    “By some estimates, it [carbon dioxide] rose nearly as rapidly as we’re putting CO2 into the atmosphere today,” Corsetti said. “We wanted to see how the Earth system responded from a rapid rise of CO2. The spoiler alert is there was a mass extinction. What we’ve been able to do is use this mercury as a fingerprint to tie the event to the volcanos, and therefore the emissions.”

    The Triassic-Jurassic extinction is particularly pertinent because it was selective, Corsetti said. It preferentially affected coral reefs and animals most similar to the ones common in today’s oceans. An earlier and more severe event, the Permian extinction — sometimes called “the mother of all extinctions” — was even bigger, but the dominant organisms affected were different from the ones common today.

    That makes the T-J event perhaps the most relevant mass extinction to study when trying to predict what might happen with rising CO2 levels, Corsetti said.


    There were massive flood basalts in the T-J event (201 Ma)–as with both the previous (K-T 252 Ma) and next (K-Pg/End Cretaceous 66 Ma) events of the big five. The T-J flood basalts were in the Central Atlantic Magmatic Province. The K-T formed the Siberian Traps (step-like features) and the K-Pg formed the Deccan Traps.

    There are fine graphics showing time frame of the T-J event in Figure 1, “Geography of the T-J interval and age model,” of the study:

    Part (a) of Figure 1 may suggest why the massive flood basalts from the T-J are not so readily obvious from geo features now.

  32. 82

    AIC, if you can find Lodders and Fegley’s “The Planetary Scientist’s Companion” (1998), I recall it tabulates several studies on volcanic gases.

  33. 83
    patrick says:

    Here’s Figure 1 (#81)–showing paleogeographic map and time frame of the T-J flood basalts. “CAMP” is the Central Atlantic Magmatic Province:

  34. 84
    Hank Roberts says:

    EG, I mention tests during the Cuban missile crisis.
    You name an earlier test and claim I’m confused.

    “… During the Cuban Missile Crisis in October 1962, both the US and the USSR detonated several high-altitude nuclear explosions ….
    … worst effects … 22 October 1962, in the Soviet Project K nuclear tests ….
    The Partial Test Ban Treaty was passed the following year ….”

    Those. That’s why. Yes, there were others earlier. That last batch convinced both sides they were stupid to continue. They agreed to stop.

    OK? You brought up earlier tests. Different. Not these. Other ones.

  35. 85
    Hank Roberts says:

    PS, and the relevance, though slight, is
    1) back then the US and USSR were capable of recognizing behavior counterproductively destroying an important resource and backing away from the gross edge of stupid.
    2) what’s the worst that could happen? Another “Deccan Traps” kind of outbreak producing — coincidentally — excess CO2 comparable to what we’re doing. Which gives some hope that if we halted our fossil fuel use and learned how to speed up removal of CO2 from the atmosphere and ocean, we’d have the knowledge needed to do it again to cope with a basalt outbreak.

    It’d be — maybe — possible. If we work really hard at being smart.

  36. 86
    Bill DeMott says:

    The idea that a volcano releases more CO2 than fossil fuels is so easily debunked that even Rush should have figured it out. Look at the Mauna Loa CO2 data. It keeps going up year after year at a consistent or increasing rate. Do you see a huge spike upward in 1992, the year of the Mt Pinatubo eruption? There is no response to the eruption. So how could the volcano have released more CO2 than the combustion of fossil fuels?

  37. 87
    Oxyaena says:

    “Without any doubt what so ever, mankind has polluted the earth. We owe it to our planet to clean it up.
    Regrettably, the notion that we are creating a greenhouse effect, no sorry, we changed to global warming…no sorry we changed that again to climate change (to cover any scare notion) just isnt true…”

    This is complete bullshit, the data shows that the climate has warmed over the past century and a half, for example, how do you explain the reduction o’ Arctic sea-ice levels, a good article illustrating the loss of the Arctic ice cap can be found here:

    “The Antartic has experienced its coldest recorded 25 year period. Farmers in Brttany farmed bare chested in the 1300s.
    Its been proven that the living organism…the Great Barrier Reef has self repaired over the last 15 years. Bleaching due to climate chamge is NOT happening. Sea levels predicted to rise by almost wo metres over 40 years ago…rose by just a natural occurance of simple 1.3cms over 40 years.”

    Cite? According to my sources, the sea level has risen 8 INCHES SINCE 1992, not “1.3cms over forty years [sic]”, you must be the worst troll I have seen in a long, long time. 1992 is a lot more recent than, say, 1976. A lot of coral reefs have suffered irreversible damage, I mean so much damage I wouldn’t be surprised if a large portion of coral reefs were to collapse.

    “Catastrophy, threatened by ill informed scientists and dumb tax seeking politicians are our worst threats. They mill fear to perpetuate their importance and calculating politicians find ways to use the fake notion of climate change to impose taxes.Mankind is not to blame for natures’ natural mankind might wish it could.”

    Yeah, mankind is to blame. Have you not even read the article, or any of the articles on this website?

  38. 88
    liquid says:

    Who still believe politicians ?
    Lots of people know they dont speak for human health but for big corporations.

  39. 89
    Taylor says:

    Good article. It is nice to see the science behind this and the disconnect between differing thought processes.

  40. 90
    Brendan P Dulohery says:

    I really liked this article! In my Climate Change course, we are learning from a text called Earth’s Climate: Past & Future by William Ruddiman, and he also points out that while volcanoes are the major cause of natural CO2 emissions, the 2013 Iceland eruption accounted for a fraction of daily vehicle emissions in just one continent, contrary to what Mr. Huckabee and others like him claim. It’s interesting that in American politics, these well-respected old boy figures can use disproven and unfounded evidence to back up their claims and never get called out for it in the news.

  41. 91

    Oxyaena, #87–Rick was indeed spewing a worthless Gish gallop of denialist bumph–“bare-chested Brittany” indeed!–but no, SLR since 1992 has not amounted to 8 inches. According to CU, it’s about 8 *centimeters*:

    Of course, that’s still a lot more than 1.3 cm since 1966, which is what he claimed.

  42. 92
    Cody Nichols says:

    I just wanted to say, this article has totally made my day. It’s both incredibly informative, and immensely enjoyable to read through. I will definitely be following your posts from here on out.
    Thank you for straightening out all of those misstatements. This is exactly the kind of fact checking that we need to follow up behind political statements with.

    Also, just out of curiosity, how would Yellowstone’s first eruption at 2.1 mya stack up against people’s CO2 production?

  43. 93
    P J Carson says:

    You do realise that 80% to 90% of volcanic activity is undersea?

  44. 94
    Hank Roberts says:

    > 80% to 90% of volcanic activity is undersea?

    and always has been, and for the most part we don’t see bubbles reaching the surface.

    That’s background, not changing. Human fossil fuel use has changed and changed very very fast.

  45. 95
    Marco says:

    P J Carson @93, you do realize that eruptions of submarine volcanoes does not emit nearly as much CO2 as subaerial volcanoes?

  46. 96
    Hank Roberts says:

    PS, for those who like that sort of thing, the linked website of
    recent commenter P J Carson

    proving that AGW cannot occur

    has a lot of it.

  47. 97

    “You do realise that 80% to 90% of volcanic activity is undersea?”

    Pretty sure the USGS does, thanks.

    You do realize that seawater reacts with CO2?

  48. 98
    P J Carson says:

    Replies 94, 95, 97.
    The point is, I addressed the author when I wrote
    “You do realise that 80 to 90% of volcanic activity is undersea?”
    As the author’s article only refers to the minor volcanic activity of terrestrial volcanoes.

    97 Kevin McKinney. I too am sure USGS knows – but do the various agencies talk together?
    “You do realize that seawater reacts with CO2?”
    Yes. My chapter 4 deals with seawater reacting with CO2 quantitatively – I’m a Physical Chemist.

    94 Hank Roberts.
    Actually, we do see bubbling.
    Chapter 2 shows that volcanic activity is changing; from the ISC.
    As I wrote here previously, but not published,
    “By the way, of Earth’s current 400 ppm CO2, 280 ppm has been produced naturally, presumably from volcanoes, and Man has produced 120 ppm – and rising. “

    95 Marco.
    “..eruptions of submarine volcanoes does not emit nearly as much CO2 as subaerial volcanoes?”
    No, I didn’t realise that. Perhaps you can reference that.

    Although the article refers to HCl being liberated, little is said about the main acidic component, H2S. (About half as much is liberated as the only weakly acidic CO2.) Although it is neutral itself, it oxidises to sulphuric acid, H2SO4, which certainly is not neutral. [Again, this is discussed on my site – but will be expanded further when I deal with El Nino.]

  49. 99

    “has a lot of it.”

    Not sure, Hank, but you might be missing a couple of letters there.

  50. 100
    Hank Roberts says:

    Kevin, I’m trying for politeness — sh!

    PJC — what is this ‘International Science Conference’ you refer to?
    There’s one out of Pakistan covering all sorts of subjects found by Google search, but I can’t find a source in Scholar? Is it indexed? Where?

    I found this, current and on point:

    A geology-based analysis of Earth’s climate history over the past 700 million years provides evidence that climate change has occurred traditionally through slow shifts in the release of carbon dioxide — a stark contrast to today’s rapid release of carbon dioxide.

    Scientists at Yale, the University of Texas-Austin, and Rice University created a global database of volcanic activity going back 720 million years, in order to study the ebb and flow of warm and cold climate that Earth has experienced. The findings appear in the April 22 edition of the journal Science….

    Mineral clues to past volcanism
    Lee Kump
    Science 22 Apr 2016:
    Vol. 352, Issue 6284, pp. 411-412
    DOI: 10.1126/science.aaf6612