This is a continuation of a remarkable thread that has now received 10,000 comments running to well over a million words. Unfortunately its size has become a problem and this is the reason for the move.
The history of the New Statesman thread goes back to December 2007 when Dr David Whitehouse wrote a very influential article for that publication posing the question Has Global Warming Stopped? Later, Mark Lynas, the magazine’s environment correspondent, wrote a furious reply, Has Global Warming Really Stopped?
By the time the New Statesman closed the blogs associated with these articles they had received just over 3000 comments, many from people who had become regular contributors to a wide-ranging discussion of the evidence for anthropogenic climate change, its implications for public policy and the economy. At that stage I provided a new home for the discussion at Harmless Sky.
Comments are now closed on the old thread. If you want to refer to comments there then it is easy to do so by left-clicking on the comment number, selecting ‘Copy Link Location’ and then setting up a link in the normal way.
Here’s to the next 10,000 comments.
Useful links:
Dr David Whitehouse’s article can be found here with 1289 comments.
Mark Lynas’ attempted refutation can be found here with 1715 comments.
The original Continuation of the New Statesman Whitehouse/Lynas blogs thread is here with 10,000 comments.
JamesP
Sorry for the digression…
About as much as Brute’s 1,500 hp “eco-mobile” at full throttle speed in (fuel saving) overdrive.
Maybe Brute can confirm.
Let’s just say the 1500HP Brutemobile® creates it’s own atmosphere and leave it at that…………
The volcano tongue twister:
Did anyone see that TV doco’ several years ago about a handicapped savant with incredible memory whom visited Iceland with a task of learning the language? He was allowed one or two (?) weeks and then appeared on local TV for an interview before a panel. (In Icelandic) Apparently, he did astonishingly well.
Volcano dust:
On another TV doco about Hong Kong airport, which is badly exposed to “wind shear”, they introduced doppler lasers that were sensitive to the invisible particle movements in the air.
Something similar might be useful, especially in the context of the huge cost etc of this debacle?
But why could they not fly at low altitude?
So far as this thread is concerned, the the key point of this volcano/flight story is not whether the authorities were right, important and controversial though that is. No, what’s important here is that it’s a perfect illustration of a simple yet basic truth: real world empirical evidence trumps theory and computer modelling every time.
I’m tempted to note that that’s especially true when the computer modelling is done by the Met Office. But of course that would be irrelevant: empirical evidence trumps any computer model. What is worth noting, however, is that modelling the dispersal of ash from a volcano is absurdly easy compared with modelling the climate in 50 years time.
Bob
I wondered that, too, but apparently commercial jets only run really happily at high altitude, and consume much more fuel in denser air. Turboprops (which are really jets with gears) seem OK, but presumably engines can be optimised for any altitude, on the drawing board at least.
Max – thanks for your help with pronunciation. I noticed that even the BBC tried to avoid it, but it’s not so bad once broken down – I might even try throwing it into the conversation!
Robin – couldn’t agree more. Do you think it’s the same model? :-)
PeterM
Volcanoes have become a “hot topic” lately.
In his book, Heaven and Earth, geologist Ian Plimer argued that volcanic eruptions emit a larger amount of CO2 than humans.
At first glance, this claim appears absurd. Studies of subaerial (land-based) volcanoes show us that these emit a far smaller amount of CO2 than humans. Gerlach et al. have estimated that, even doubling the amount of CO2 from subaerial volcanoes to account for submarine volcanoes and rifts, would put volcanic CO2 at 130-230 million metric tons, compared to 30 billion metric tons from human activities, including fossil fuel burning, cement production, land clearing and gas flaring,
But is this estimate realistic, or does Plimer (as a geologist) know something we are overlooking?
Writer O’Sullivan cites a study on submarine volcanoes:
Now 3.5 million submarine volcanoes begin to sound like a fairly substantial number, especially when we compare it to the 600 or so subaerial volcanoes that have had known eruptions during recorded history.
http://international-environmental-affairs.suite101.com/article.cfm/acid-oceans-due-unders
ea-volcanoes-not-humans
If the Hillier and Watts estimate of 3.5 million submarine volcanoes is correct, and only one-third of these are active and emitting the same level of CO2 emissions as the subaerial volcanoes measured by Gerlach, then the amount of CO2 emitted would be:
(1,170,000 / 600) * 130 to 230 million mt/yr = 250 to 450 billion mt/year
Humans = 30 billion mt/yr
Submarine volcanoes = 8 to 15 times human emissions.
Since the isotopic composition of volcanic CO2 and human CO2 emissions from fossil fuel are identical, there is no way to be certain what is causing the acidification of the oceans.
O’Sullivan argues that if the ocean acidification came from human CO2 emissions to the atmosphere, a similar acidification of fresh water lakes and reservoirs would occur. Since this acidification has not occurred, it is quite possible that most of the observed ocean acidification has come from somewhere other than the atmosphere, i.e. from submarine volcanic eruptions.
Another study has shown how submarine volcanic eruptions may actually help the oceans process larger amounts of CO2 through photosynthesis.
http://www.inhabitat.com/2010/03/16/underwater-volcanoes-help-suck-carbon-from-the-air/
So, it appears that the whole story is much more complicated than one would think from first glance.
And Plimer may well have been spot on with his statement that volcanoes emit more CO2 than humans.
Max
Ain’t that the truth! Perhaps the Met Office should reconsider its climate forecasts, when it appears unable accurately to map the cloud from a single volcano over a matter of days…
Max 332
As you know I was sceptical of Plimers assertions on Co2 emissions as he made them without any back up figures i.e. based on what is currently published.
Having spoken to vulcanologists when visiting my son at Cambridge University, it is apparent that all believe the number of volcanoes is greater by a very big factor than what has been believed until recently.
So it is likely they do contribute a much greater anmount of Co2 than previously believed, but I do think Plimer ought to publish his figures.
A second factor is that according to the IPCC a significant % of Co2 remains in the atmosphere for a thousand years. Therefore we need to take into account the emissions from volcanies for the 950 years prior to mans recent additions.
Tonyb
TonyB
Yes. I was skeptical of Plimer’s claims at first, as well, but it appears that latest studies may validate them. Apparently some 200,000 submarine volcanoes have already been identified and scientists believe there may be more that 10 times this number, which have not yet been identified, in regions which have not yet been explored..
At any rate, it appears that the Gerlach et al. estimate made back in the early 1990s is outdated. This estimate was the basis for the “mainstream” opinion that CO2 emissions from volcanoes were much less important than those from human activities. This opinion may now need to be reconsidered, in light of the newest data.
You wrote:
This is a good point, although I do not believe the “thousand year” estimate for remaining “in the atmosphere”. Several studies have shown that this is less than 15 years. But the CO2 does apparently remain “in the system” somewhere for a longer period, maybe even hundreds of years. This means (as you say) that the emissions from past volcanoes may be just as important as anthropogenic emissions of today, as far as greenhouse forcing is concerned.
The one study I cited showed that massive amounts of CO2 are absorbed by phytoplankton (and converted to oxygen), and that this process, itself, is enhanced by iron contained in submarine volcanic emissions, in sort of a “negative feedback”.
At any rate, if these new studies turn out to be conclusive, it will shed a whole new light on the relative importance (or lack thereof) of human CO2 emissions.
Max
Max,
15 years is obviously too short a time for even the half life of CO2 in the atmosphere.
Currently the increase in C02 levels is just about, and to keep the numbers simple, 1ppmv per year. The Earth and oceans absorb about half, and again to keep the numbers simple, so it would be 2ppmv per year if it didn’t absorb any at all.
If the Earth didn’t absorb any then the CO2 would stay there for ever even if human emissions suddenly stopped. However, if they did suddenly stop, the earth would next year still take up the same 1 ppmv as it did this year.
So on the basis that the Earth always takes up half, the natural fall in CO2 would be at exactly the same rate as the rise we’ve seen in the last 150 years.
I’m not sure how the IPCC calculates its figures but the danger is that the oceans and earth will find it increasingly difficult to take up their half share as CO2 levels increase. In that case the rate of fall would be much less than the rate of increase.
Obama Earth Day Flights Burned More Than 9,000 Gallons Of Fuel
http://www.cbsnews.com/8301-503544_162-4962384-503544.html
Obama/Biden Celebrate Earth Day by Tying Up New York Air Traffic…
http://nycaviation.com/2010/04/21/obama-and-biden-to-celebrate-earth-day-by-flying-separate-carbon-belching-jets-to-the-same-city/
Potentially deadly fungus spreading in US, Canada
http://www.alertnet.org/thenews/newsdesk/N22129903.htm
Max and Robin,
I’ve been thinking about your repeated calls for empirical evidence that mankind’s CO2 emissions are responsible for temperature rises. It seems that you aren’t totally convinced that the evidence is as strong as some people might claim.
So, lets just say, for the sake of argument, that you are right. To resolve the question, we need to do some experiments, we need more tests.
So, how about we reduce CO2 emissions down to about 20% of their current levels for the next 100 years or and see what happens? If mainstream science is right we should see CO2 concentrations slowly fall in the atmosphere and the temperature fall with it, but maybe after a 20 year or so time lag. After a couple of hundred years we can then let it rise again, then we’ll let it drop once more and see if the whole process is repeatable. Just another 500 years, which isn’t long in Geological terms, and we’ll all be much closer to an agreement.
Its a pity that we won’t be around to see that but, as we all agree that science should be done thoroughly, with no corners cut, it would seem to be the only way to resolve the issue a little more “uniquivocally” ( was that the term you used? )than we can at present.
I meant “unequivocally”. Mustn’t have had my spell checker switched on.
PeterM (#339):
Yes, that’s quite funny. But, you know, there’s no need for your “experiment”. As things are, man’s CO2 emissions have been increasing for years and that’s set to continue: whatever the developed West may do to reduce them (almost certainly nothing on current form), the developing economies, already emitting more than the West, haven’t the slightest intention of reducing theirs – see this (and read my #15). So emissions will continue to grow and grow. And grow. Until, that is, the day when mankind finds an economic and viable alternative to fossil fuels. Then, maybe in 100 years, CO2 emissions will start to fall. All you have to do, Peter, is wait and see what happens to temperatures over this period: is there a correlation between emissions and temperature? That might resolve it for you. Of course, you already have a clue to the answer: there’s little sign of correlation in the historical record.
So, no need for your “experiment”.
PeterM
You wrote:
If you will recall, we discussed this once before.
A study by Tom Segalstad gives an excellent summary of atmospheric residence time of CO2 based on 36 different studies using 6 different analytical methods; the average residence time is 7.6 years.
http://folk.uio.no/tomvs/esef/ESEF3VO2.htm
And Brute also posted the results of several studies on this (263) (possibly from the same summary). Most of the studies showed atmospheric CO2 residence time of below 10 years (average was 7.5 years). Only one study was above 20 years (except, of course, for IPCC, which was over 100 years).
These data are based on actual analytical procedures (not simply model simulations).
As we saw from the volcano data, things are much more complicated than the oversimplified IPCC assumptions based on the myopic fixation on atmospheric anthropogenic CO2 as the principal driver of out planet’s climate.
Where does the CO2 go? The ocean is a massive carbon sink, not only as dissolved CO2 (actually carbonate and bicarbonate ions in a slightly alkaline environment), but even more as plant life in the billions of tons of phytoplankton that apparently thrive on slightly higher CO2 concentrations. This carbon then enters the life chain; a significant portion eventually ends up as calcium carbonate, which settles to the bottom of the ocean, leaving the short-term “carbon cycle”. The very small portion that “stays in the atmosphere” is insignificant in comparison.
As the studies I cited earlier point out, it is highly likely that a major portion of the added CO2 going into the ocean (and entering the life cycle there) is not coming from the atmosphere, as originally assumed, but rather from the large number of suboceanic volcanoes. The fact that fresh water reservoirs around the world are not showing increased CO2 concentrations indicates that increased oceanic CO2 concentrations are most likely not coming from the atmosphere, as the study points out.
At any rate, it is pretty certain that the atmospheric residence time of CO2 is on average somewhere under 10 years, based on all the many studies made.
Max
PeterM
Robin is right, of course.
In our “experiment”, we do not have to resort to the drastic and very painful plan to “reduce CO2 emissions down to about 20% of their current levels for the next 100 years or and see what happens”, as you suggest.
Besides, as Robin had told you many times, the “developing nations” have no intention ahatsoever of embarking on such a path.
All we need to do is continue emitting CO2 at the rates that make sense for our world-wide economic development (as we are now doing), and see what happens.
If we see a continuation of the cooling trend we have actually seen after 2000, despite record CO2 increase, we will know that AGW is not the principal driver of our planet’s climate, after all, and the premise of a serious potential threat from AGW will have been invalidated.
If we see a return to a slow warming trend, as we have observed in multi-decadal spurts since 1850, we will still have the dilemma of explaining these oscillations despite gradually increasing atmospheric CO2.
If we see the warming go as the IPCC models project, then we can look at the appropriate adaptation strategies. But let’s see which IPCC projections pass the “sanity test” to start off with.
The top two IPCC projections (A2 and A1F1 scenarios) are physically impossible in any case (there is not enough carbon in all the fossil fuels on Earth to reach 1000 ppmv, let alone 1280 or 1570 ppmv, as projected).
The next three projections (A1T, B2, A1B scenarios) show CAGR of atmospheric CO2 that are 1.5 to 2.5 times those actually seen for the past 5 or 50 years, so do not pass the “reality” test either, and can therefore also be discarded.
So we are left with scenario B1, which predicts warming of 1.1 to 2.9C above 1980-1999 averages by 2100, or 0.8 to 2.6C above 2009 temperature.
So we do nothing (except record temperature and CO2 levels) until we have seen warming of, let’s say, 0.5C above the 2009 temperature (annual anomaly equal to 0.94C).
Let’s say this happens by year 2060 or so.
By then we may know more about the natural variability (a.k.a. natural forcing factors) that caused the multi-decadal oscillations in the past plus the post 2000 cooling despite record CO2 increase.
So we may know that the warming to an anomaly of 0.94C was not caused primarily by human CO2, but by something totally different. In this case we don’t need to worry about reducing CO2 at all, but just need to concentrate on adapting to our climate (as we have been doing for centuries).
If, by then, we truly have conclusive evidence that human CO2 has caused the 0.5C warming after 2009, we can look at the pros and cons of a slightly warmer world. If we conclude, based on an exhaustive analysis of the pluses and minuses of a warmer world, that an added warming of 0.5C or more would be more harmful than beneficial, we can look at curtailing CO2 then, when new technologies, such as nuclear fusion (and others not even imagined yet) are available to make a smooth and painless transition.
Sounds like a more reasonable (and much less costly) “experiment” than yours, Peter.
What do you think?
Max
Max and Robin,
Yes, just as I thought. You lament the so-called decline in scientific standards and methodology, but it is you who are arguing that normal scientific procedures shouldn’t be thoroughly followed.
You can’t have it both ways much as you would like to.
I see that interest in carbon offsets is running high………now’s the time to buy this hot commodity!
PeterM:
Please show me an example of my “arguing that normal scientific procedures shouldn’t be thoroughly followed”. Thanks.
Detection and attribution of climate signals, as well as its common-sense meaning, has a more precise scientific definition.
The point you have been making, in more scientific terms, is that the IPCC is claiming a detection of a climatic signal but that it cannot be described as an attribution in the classical scientific sense.
“Correlation does not demonstrate (or prove) causation” is the oft used phrase. Unequivocal attribution, which is the closest that science comes to what the layperson, or lawyer, might refer to as proof beyond any reasonable doubt, requires controlled experiments with multiple copies of the climate system, which, of course, is impossible.
What is just about possible, although it is so difficult as to be almost amusing as you pointed out, is to perform long term experiments on just the single climate system to which we do have access.
You have asked for unequivocal and unambiguous evidence that the detected climate signal is attributable to human emissions of CO2 and other greenhouse gases. Yet you are ruling out as unnecessary normal scientific procedures, the very procedures that are needed to meet the ultra-high standards of verification you demand.
PeterM
You wrote (344):
Sorry, Peter, I cannot figure out what you are talking about here.
I’m all for following the “scientific method” (see my post #343), rather than just relying on model simulations, which are only as good (or bad) as the input assumptions.
The step by step approach I outlined in 343 is the most logical approach to test the AGW theory in actual practice at the lowest possible cost. It allows for the implementation of appropriate adaptation steps if and when it becomes apparent that this is required, while avoiding taking costly mitigation steps before we even know that we need to do so or that these steps will accomplish anything.
I asked you for comments to this approach, but only received your confusing sentence above (which really has nothing to do with our topic).
Max
PeterM
In your 347 you seem to favor the “scientific method” for testing the premise that AGW, caused primarily by human CO2 emissions, has been the principal cause for the warming we have experienced, and represents a serious potential threat.
So do I, as outlined in my 343.
Please comment.
Max
Apr 20, 2010
Porn surfing rampant at National Science Foundation
http://www.washingtontimes.com/news/2009/sep/29/workers-porn-surfing-rampant-at-federal-agency/