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Did we call it or what

Filed under: — david @ 8 November 2007

Steve Milloy has let fly with the results of his twisted survey of climate scientists, pretty much as we expected. It’s not worth analyzing in any great depth, I’m sure we all have better ways to spend our time, but one tidbit jumped out at me.

The first question of the survey was

Which best describes the reason(s) for climate change?.

The survey offered a choice between human activity or natural variation, or some combination of the two. How to answer this? Before a few decades ago, natural variability was the right answer, but since about 1970, human activity has taken over.

I emailed Milloy with my concern about the indeterminate time scope of the question, and he replied

Hi David,

Present tense verbs imply ongoing climate change.

but now from the press release,

Another notable result is that an astounding 20% of those surveyed said that human activity is the principal driver of climate change.

“So was there no climate change before mankind?” Milloy asked.

The rest is more of the same. Garbage in, trash talk out. OK, back to work, enough time wasted on this.


283 Responses to “Did we call it or what”

  1. 101

    Re:#80 Where in Oreskes study did you find this
    “…….. Oreskes conclusion (100% of scientific papers agree with IPCC)………” can you cite this conclusion? I don’t think so. This not stated in the study. Could this be…. “a rhetorical… artifact rather than an objective assessment on..” her conclusions?

  2. 102
    Jim Galasyn says:

    Hey Bob, congrats on getting your letter published — it certainly stands out among all the denialist letters on that page.

  3. 103
    Nick Gotts says:

    Re #66 (Richard Ordway) “But, the Brits did not give up even when in a nearly hopeless situation against near overwhelming odds…and won anyway.”

    - with a little help from allies!

  4. 104
    Charles Muller says:

    A detail: About solar forcing (recent exchange Jim / Gavin), it would be more precise to say no trend since 1980 rather than 1960 (Lockwood and Frohlich 2007 or Usoskin and Solanki 2003 agree on that). If I recall correctly, solar cycles 21 (peak in the 1980s) and 22 (peak in the 1990s) were more active than cycle 20 (peak in the 1970s), so it does not exclude an influence of solar forcing in the initial phase of recent and significant warming (from 1977 onward). But not for 1990-2007 in our current undestanding of solar effect on climate.

    (Anyway, cycle 23 was less active than the two previous and we must hope the coming cycle 24 will be still less active than 23: this would be of great help for interpretation of climatologies regarding solar influence in stratosphere, troposphere and surface).

  5. 105
    Jim Cripwell says:

    Ref 95 I fail to see how John Tyndal in 1859 could have done any experiments of what effect an increase of CO2 in the 20th century has on a 20th century temperature rise. Of course, CO2 is a greenhouse gas; a very minor one, but it still has a significant effect at low concentrations. The disagreement is how saturated the effect is. On this aspect, there is no experimental data.

  6. 106
    Jim Galasyn says:

    Re solar forcing, you’re both wrong. It has been definitively shown that the warming trend is strongly correlated with the decline of pirates:

    http://www.venganza.org/about/open-letter

    It’s all there in the numbers.

  7. 107
    Jim Cripwell says:

    Ref my 96 Gavin writes “This is hardly a scientific attitude and you wouldn’t apply this kind of logic to any other scientific issue” I do resent being told that I do not have a scientific attitude, and I hope you will post this rebuttal in full. My position is perfectly scientific, if you would only read everything I have written. It does become a bore rewriting the same things over and over again. First, from my previous work on CO2, I found it impossible to believe that adding any more CO2 into the atmosphere, over pre-industrial levels, could cause the sort of effects claimed by AGW. There is correlation to be sure, but I note that there is no experimental data that connects the recent alleged rise in temperature with the recent rise in CO2 concentration. Hence AGW is merely a hypothesis, with no supporting experimental data. If CO2 is not causing the recent warming, then something else must be. That something is, I believe, the sun. There is a great deal of correlation with things that happen on the sun, and the earth’s climate; e.g. the number of sunspots in the middle of solar cycles when the sun ought to be active, correlate very well with both warm and cold periods on earth. Notably the Maunder minimum, and the 20th century, when the sun has been more active than average. However, there is no obvious physics that accounts for this correlation. There is no comprehensive physics that expalins, in detail, the various cold and warm periods that the earth has experienced over the years. There are hypotheses, but, again, no experimental data. We are, therefore, faced with two hypotheses, neither of which has any supporting experimental data; AGW and the sun. I choose to believe the sun is the cause, and I fully expect that when the hard data comes in, I will be proved to have been correct.

    [Response: Even by your logic that makes no sense. You claim no knowledge supports either GHGs or the sun, and you are therefore confident it must be the sun. Why? The logic of your presentation should only lead to complete agnosticism. But in reality there is plenty of positive evidence - changes in radiation spectra at the top and bottom of the atmosphere show exactly what is expected from increases in GHGs, predicted effects are seen (strat cooling, more warming over continents than land, winter than summer), models runs from almost twenty years ago match what was seen etc. Solar forcing is fine as a theory and I've written half a dozen papers on the subject - it's just not relevant today (just like orbital forcing, the opening of Drake's Passage, or the massive final drainage of Lake Agassiz aren't relevant either). Meanwhile, the people who used your argument in the 1980s, 1990s and today keep bringing it up as if no additional evidence is ever presented. It is indeed 'a bore'. - gavin]

  8. 108
    John Mashey says:

    re: #94 Charles on my URL in #8
    Oops, sorry, the extra period snuck in. Correct for Oreskes’ essay is:

    http://www.ametsoc.org/atmospolicy/documents/Chapter4.pdf

  9. 109
    Richard Ordway says:

    re. 107 Gavin, you mean more warming over land then the oceans don’t you?

    You wrote
    “more warming over continents than land.”

    [Response: Err... yes. In my defense, it was written during a Sunday morning repose.... Thanks - gavin]

  10. 110
    Timothy Chase says:

    rk (#90) wrote:

    Re: Timothy Chase and Russell Seitz and the hoax. Sorry to burst your bubble, but Rush corrected the hoax immediately after the commercial. Laughed at getting hoaxed, told people to ignore the segment. Then Spencer put an apology on Rush’s webpage for issuing a poorly worded note to Rush, that mis-led him.

    I don’t know if you’ve noticed, but I haven’t regarded Rush Limbaugh’s “mistake” as being all that central in this. It isn’t about Rush. In fact, at root it isn’t even about climatology or even the nature of science, but something much more fundamental and profound as well as something ancient and primitive. However, lets focus on something a little closer to your current range of interests.

    Even at the most superficial level, the hoax proved its point. If you look at the article referenced in George Darroch’s 69, it states:

    Skeptics jumped on the report. A British scientist e-mailed the report to 2,000 colleagues before spotting it was a spoof. Another from the U.S. called it a “blockbuster.”

    Blogger skeptic Neil Craig wrote: “This could not be more damaging to manmade global warming theory … I somehow doubt if this is going to be on the BBC news.”

    Hoax bacteria study tricks climate skeptics
    Thu Nov 8, 2007 3:25pm GMT
    http://uk.reuters.com/article/environmentNews/idUKL0887458220071108

    It was a splash with much of the skeptic community, even with scientists who should have known better than to simply assume that a single technical paper will overturn decades of science.

    In all likelihood the latter should have seen the problems with the paper’s thesis simply in terms of ocean chemistry and the fact that the ocean is not presently an emitter of CO2 but a sink. The carbon dioxide which is entering the climate system in entering through the atmosphere — and in terms of its distribution (as determined by satellite imaging), it is largely coming from regions of high population density. They should also have known that matching the trend of rising atmospheric CO2, we have the trend of falling atmospheric O2 — caused by the consumption of oxygen as we burn fossil fuels. And they should have known that the lighter carbon isotope marks the CO2 as the product of fossil fuel use.

    However, from my perspective, what most eloquently demonstrated the central conceit of the hoax were the few skeptics who saw through it — and panicked.

    Roy Spencer is the best example I have seen so far:

    Several of us (scientists and non-scientists alike) were able, within a matter of seconds to minutes, to identify the paper as a fake. We then spread the word, warning others of the hoax. Therefore, we showed that we do not, as the hoaxer claims, “believe almost anything if it lends support to their position”. We did exactly the opposite.

    As I said in 77:

    Spencer could smell the hoax. It would have been hard for anyone with a passing familiarity with the ocean chemistry, benthic bacteria or CO2 levels and emissions not to.

    But how many others? And why did they think it necessary to “spread the word” — unless they were just as convinced as the hoaxster that there would be those, some prominent, who would buy into it?

    You have to admit, there is a certain princely poetry to Spencer’s warning having been misinterpreted by his friend, bringing about exactly what it was intended to prevent, isn’t there?

  11. 111
    Paul Harris says:

    One more ‘refutation’ of AGW hit the streets last week. It is the book “Scared to Death”‘ by Chrisopher Booker and Richard North (two columnists on the conservative British paper The Daily Telegraph). It is favourably reviewed at this website: http://eureferendum2.blogspot.com/. As you will see, all the usual suspects are lined up: the Mediaeval Warming, the infamous hockey stick, the misleading Al Gore and once again the answer is to be found in the stars. Well, in one star in particular, its all due to radiation from the sun!!

    “Enjoy” or is that the wrong word when attempting to digest such dross?

  12. 112
    Bob Clipperton (UK) says:

    re#102 Thanks Jim

  13. 113
    rk says:

    @ Timothy Chase #110

    This just gets richer. Ok, I bit and looked up Neil Craig. Seems to have a comic store/Sci-Fi store in the UK, and (at least former) Lib-Dem. Evidently quite a famous blog to the Reuters/BBC crowd (must remember to put on favorites list). Let’s see, did the hoax fool CA (no), Chris Horner (no), Roy Spencer (no), Junk Science (no). Did it hoax a radio personality for 4 minutes (yes), did he correct (yes), did he laugh about getting hoaxed so everyone knew it exactly what it was (yes). The guy said it took him four days, which (if you saw it you know is true). The poor guy didn’t even make it to Media Matters, which would have Loved to Bash Limbaugh. Sorry, the guy’s 15 minutes of fame is over. Move On.

  14. 114
    rk says:

    If the moderator permits one PS to my post: In looking a the Neil Craig stuff, I found that the manager of the famous model is dis-avowing the “dollar dumping” story on Bloomberg, saving “Some idiot in Brazil reported something just to make news.”. Like I said, I think its time to move on from this small story.

  15. 115
    Jim Eager says:

    Re 107 Jim Cripwell: “It does become a bore rewriting the same things over and over again.”

    Not to mention reading the same things over and over again.
    Fortunately there is a very easy solution at hand, at least on the receiving end.

  16. 116
    Dave Rado says:

    Re. Jim Cripwell, #105:

    CO2 is a greenhouse gas; a very minor one,

    I suggest you educate yourself about atmospheric physics before posting any more ill-informed ramblings. A good place to start would be here.

  17. 117
    Chris C says:

    Interesting discussion between Jim and Gavin, but a few extra points.

    Jim, you may want to view some of the more recent literature on solar activity (e.g Foukal et al 2006; Ammann, Caspar et al. 2007; Lockwood and Frohlich 2007) but there are plenty of others. Solar activity certainly did play a major role in climatic activity over, say, the maunder minimum or some earlier century warming. Earth’s position relative to the sun, or Earth’s tilt effecting how solar radiation is distributed played a role over geologic time. However, there is no trend since about 1950- and it may even be a bit negative. As concluded in countless papers, anthropogenic factors are are main forcing mechanism for climate change after mid-century, or from pre-industrial times.

    So, we have satellites showing the sun isn’t changing, cosmic-ray monitors showing they aren’t changing, we know heat is going in the ocean and not going out, we know about the downward infrared flux, the stratosphere cooling, among many others things which allow for attrbution with high confidence. We also know the CO2 physics- we’ve known this for a long time now. So, even if the sun is strongly positive, you can’t just “replace” CO2, you need to add CO2 on top of the solar forcing, and you get more reason for concern. As gavin says, if you want to put hopes on a phantom cycle, you’re welcome to it.

  18. 118
    Lynn Vincentnathan says:

    OT, but I have a Q & need an answer by tomorrow 11 am (CST) for a presentation I’m giving on “Recent Trends in the Media on GW” at my U.

    Going through the news items on ClimateArk ( http://www.climateark.org/shared/reader/welcome.aspx?linkid=57919 ), I came across this 2006 article “Climate change could cause earthquakes and volcanic eruptions, scientists say,” part of which reads:

    A number of geologists say glacial melting due to climate change will unleash pent-up pressures in the Earth’s crust, causing extreme geological events such as earthquakes, tsunamis and volcanic eruptions.

    What do you think about it?

    And is it possible that the huge volcanic eruptions during the end-Permian may have in part been caused by warming changing the ice/snow pressure? — the volcanic eruptions supposedly responsible for triggering the warming and positive carbon feedback hysteresis scenario that eventually led to 90%+ extinction of life?

    In other words, could there have been some positive feedback between warming-eruptions?

  19. 119

    Re #89 Ely Times, another thing that nobody got around to pointing out in all the excitement over the Benthic Hoax, is that the editorial the Dr Mann commented on, while not “really a contrarian hit piece”, was something more insidious and in its own way just as dangerous: an attempt to plant misleading memes.

    Call it “lying with facts” if you like. “CO2 is not a poison”. Right. Agreed. The stuff isn’t toxic. “At one time there was alot more CO2 in the atmosphere than there is now”. Again agreed. No argument. But why are those factoids being planted here? Perhaps in order to be read like “CO2 is not dangerous”, “We’ll get used to those higher concentrations”, as will happen in the minds of many context-unaware readers?

    Michael Mann was fully justified in responding as aggressively as he did. I found his response still too meek — a newspaper editor is reponsible for what he writes, even if he got fooled by others into doing so (which may be the case here). Also Dr Mann could have been more specific, mentioning, e.g., the PETM as an illustration that rapid CO2 increases can be pretty disruptive even if natural.

    A see way too much of this “lying with facts” going on. I can tell from the questions people ask me that they’ve been reading the wrong web sites ;-/

  20. 120

    Jim Cripwell writes:

    [[The disagreement is how saturated the effect is. On this aspect, there is no experimental data.]]

    There is plenty of experimental data dating to the 1940s. CO2 line saturation is well understood and has been for a long time, and it doesn’t make CO2 ineffectual as a greenhouse gas at high concentrations. Otherwise Venus would be a lot cooler than it is.

    Will you please crack a book and learn about this stuff before pontificating about it? If you don’t want something mathematical like Good and Yung’s “Atmospheric Radiation” (1989), then try Spencer Weart’s “The Discovery of Global Warming” (2003), which describes the history of the controversy in non-mathematical terms.

  21. 121

    Pimping another link, I just added a page to my climatology web site debunking one of Alexander Cockburn’s editorials:

    http://members.aol.com/bpl1960/Climatology.html

  22. 122
    John says:

    #40
    Answer to the question on readiative forcing :
    Radiative forcing is measured in watts per square meter. The Earth system absorbs about 237 watts per square meter from the Sun, on average. But the surface, at 288 K, radiates about 390 watts per square meter. The difference, 153 watts per square meter, is the “greenhouse forcing.” It is estimated that doubling CO2 will cause the difference to widen by 3.7 watts per square meter, enough to raise the Earth’s mean surface temperature about 2.8 degrees K. given all the known feedbacks.

    Can you clarify this for me ? In order to ‘widen the gap’, either less radiation is being received or more is being radiated. I can’t quite understand this – if less is being received- then we shouldn’t be warming up. And why would CO2 make the surface radiate more ? Can you clarify ?

    THANKS
    John

  23. 123
    Nick Barnes says:

    John @ 122: First, consider the Earth’s surface in equilibrium. It receives some heat from the Sun, but radiates more heat. The surface must be receiving additional heat from somewhere (otherwise it is losing more heat than it absorbs, so is not in equilibrium). This “somewhere” is the atmosphere, which absorbs some of that outbound radiation and returns it to the surface. This absorption is the greenhouse effect, and is due to the composition of the atmosphere.
    Now, change the composition of the atmosphere to increase the greenhouse effect. Allow the system to reach equilibrium again. Plainly, this equilibrium will be at a higher temperature.
    I’m not familiar with the exact numbers for the radiative balance (the 390 W/m^2, 237 W/m^2 etc), but this is the general idea.

  24. 124
    Nick O. says:

    Regarding ‘climate change sceptics’, the following has just come up on the BBC, and is worth a read:

    http://news.bbc.co.uk/1/hi/sci/tech/7081026.stm

    Re John #122: herewith a somewhat simplistic answer, but I hope it makes sense.

    The ‘gap’ in question is the difference between the interior and incoming energy sources, which can treated as a +ve quantity (an input to temperature, if you like), and the radiated energy, which can be treated as a -ve quantity (a reduction in temperature, by the same token). The interior sources are mostly accounted for by the Earth’s own heat output at its core, which is well manifested by the geothermal gradient (which is one of the reasons why it is so damned hot in coal mines, gold mines etc. very deep underground). The Earth’s interior heat sources are driven largely by radioactive processes, so they don’t change much over short periods of time e.g. 100 years. Hence, the main factors changing the energy balance are solar input and the ability of the atmosphere to chuck the stuff back into space. So, if you add the solar input (c. 237 W.m-2) and interior heating (c. 153 W.m-2), and subtract the radiated (c. 390 W.m-2), your ‘gap’ is just about zero, hence the stable(ish) climate over the last few millenia. Now, if you change the radiated component, that is *reduce* it, by c. 3.7 W.m-2, you now have an energy gap: solar input + interior heat is still 390 W.m-2, but radiated is now only c. 386.3 W.m-2. We therefore move towards a modest energy surplus, which means we warm up, and this continues until the Earth is warmed enough to radiate at c. equilibrium again. The main arguments are over the rate and extent of the warming, and the presence of positive and negative feedbacks within the Earth system, but the main heating sources (interior heat and solar output) are assumed to hold broadly constant.

    Hope that helps/clarifies.

  25. 125
    Timothy Chase says:

    rk (#113) wrote:

    This just gets richer. Ok, I bit and looked up Neil Craig. Seems to have a comic store/Sci-Fi store in the UK, and (at least former) Lib-Dem. Evidently quite a famous blog to the Reuters/BBC crowd (must remember to put on favorites list). Let’s see, did the hoax fool CA (no), Chris Horner (no), Roy Spencer (no), Junk Science (no). Did it hoax a radio personality for 4 minutes (yes), did he correct (yes), did he laugh about getting hoaxed so everyone knew it exactly what it was (yes). The guy said it took him four days, which (if you saw it you know is true). The poor guy didn’t even make it to Media Matters, which would have Loved to Bash Limbaugh. Sorry, the guy’s 15 minutes of fame is over. Move On.

    It fooled Rush Limbaugh for only 90 seconds, but apparently it duped Sean Hannity of Fox News as well:

    Institute of Geoclimatic Studies finds basic flaw in Global Warming Consensus.
    How could we have missed this!!? Boy! Our face is red!!
    November 8th, 2007, 2:30 pm
    http://forums.hannity.com/showthread.php?t=403151

    It came out in Great Britain first on a list with 5000 members which advertises itself as having “more than 1000 astronomers and researchers who work in almost every field of planetary and Earth sciences but also many hundreds of science writers, columnists, and news editors.” It was announced by the editor of the list, Benny Peiser, a sociologist.

    However, as I said, that wasn’t my point (#110).

    Roy Spencer and others who saw through the fraud then thinking it necessary to “spread the word” proves that they thought the hoaxster was right about the “skeptic” movement and the largely emotional basis for its beliefs. It was their concession that he was right. Likewise, they are tolerant of a great deal of other dishonesty in their “movement”. Please see Curve manipulation: lesson 2 on E.G. Beck and Swindled! on The Great Global Warming Swindle for refutations of a couple of examples. Then there is physicist Fred Singer who goes from claiming that global warming isn’t happening to the claim that it is unstoppable.

    But for another example, consider one of the reactions to the paper on benthic bacteria:

    I was suspicious of the researchers when I noted that they still believed that changes in CO2 levels drive climate changes and claimed to correlate their bacterial populations with temperature change through some remarkably congruent graphs, though other evidence strongly suggests it is more likely the opposite. Recent research shows that temperature changes occur several hundred years BEFORE temperature change. But that’s a topic for another discussion.

    by Brooks Mick
    The Cause of Global Warming Discovered?
    November 08, 2007 02:00 PM EST
    http://www.theconservativevoice.com/article/29141.html

    How many “skeptics” believe this is a valid criticism of anthropogenic global warming? That scientists are arguing for linear causation rather than positive feedback?

    All of this dishonesty is tolerated and left almost completely unchallenged in the “skeptic” movement because it isn’t a rational movement devoted to reality but one driven by emotion and political ideology – and is largely held together by a psychology which is more concerned with solidarity to the tribe than fidelity to the truth.

  26. 126
    Timothy Chase says:

    Martin Vermeer (#119) wrote:

    Michael Mann was fully justified in responding as aggressively as he did. I found his response still too meek — a newspaper editor is reponsible for what he writes, even if he got fooled by others into doing so (which may be the case here).

    I think that Michael Mann acted appropriately.

    According to Aristotle, excellence consists of acting at the right time, in the right place and the right way, and for the right reasons. However, Aristotle also believed that man is a political animal. One should act as one would have others act. One should stand as an example, and as such one’s actions should be tempered to a degree that recognizes the need for others to understand why one acts the way in which one acts.

    … or at least, this is how I understand the situation.

  27. 127
    Jim Cripwell says:

    Ref 117 Chris writes “However, there is no trend since about 1950- and it may even be a bit negative”. I will merely point out that solar cycle 24 has not yet started. There are numerous forecasts as to how active solar cycle 24 will be, but there is general agreement that the later the start, the lower the activity is likely to be at maximum. Dr Hathaway, of NASA, says that the sun is sending “mixed signals”. There is at least one forecast that predicts a maximum sunspot number of 50 or less for solar cycle 24. If this is true, we may not have seen the sun this quiet for nearly 300 years. There is a developing consensus that we may be heading for something like the Dalton minimum. I am not sure whether one could classify this as a “trend”, should it occur.

  28. 128
    David B. Benson says:

    Lynn Vincentnathan (118) — Briefly, no, not possible. At greater length, adding or subtracting mass in the form of water or ice does cause some rather minor earthquakes and, it seems, may affect the exact timing of large ones.

    Valcanoes, on the other hand, are due solely to energies supplied from deep with the earth’s crust and so even the timing is unlikely to be affected by the presence or absence of ice.

  29. 129

    Re #116 Climate change and earthquakes: yes there is a connection. It’s called isostasy. Patrick Wu, a co-worker of Dick Peltier (U. of Toronto) who have been studying this complex of problems, knows what he is talking about (although the quote in the article is a bit lame).

    What happens is the following. When a continental ice sheet melts or retreats, the pressure on the underlying rock diminishes. It responds to that immediately (elastically), and with a delay (plastically). In Fennoscandia and Canada the Earth’s crust continues to slowly uplift (order 10 mm/a) after the last deglaciation; isostatic equilibrium still isn’t fully restored.

    These processes are accompanied by seismic activity. In Fennoscandia, microseisms only instrumentally observable, but the Earth’s crust bears traces of recent tectonic motions along pre-existing faults. Undoubtedly such motions during the latest deglaciation were accompanied by seismic activity.

    What happens when, e.g., the Greenland ice sheet melts, is first that mass is redistributed: a huge lump of ice disappears from Greenland. This changes the gravity field of the Earth: the attraction of the ice disappears and as a result, the melting water will seek to go to the Southern oceans. This is somewhat counterintuitive: around Greenland, sea level may even go down relative to the coastlines. Even as far away as New York and London, sea level rise will be well below average, but around the Southern oceans it will be above average.

    There are two responses to post-glacial deloading: elastic (small) and plastic. The plastic response involves the asthenosphere, a layer of slowly-deformable mantle rock under the lithosphere or brittle surface layer of the Earth. Under Fennoscandia, asthenospheric masses slowly flow back into the space evacuated by the rising crust.

    Returning to the Greenland melting, what would happen is that
    1) relieved from the load, Greenland tries to move up
    2) the released water presses the ocean floor down, especially on the Southern hemisphere.

    The amount of asthenospheric matter that process 1) wants to suck up is roughly equal to what process 2) produces… only, it is in the wrong place. Therefore the matter squeezed out from under the ocean floor goes initially to nearby continental margins, which are thus being pushed up. This is known as the ‘cantilever effect’.

    Expect earthquakes to happen primarily at the ice sheet’s rim, but secondarily at continental margins, especially on the Southern hemisphere.

    It seems that all the good articles on this are subscription only. Look for authors Peltier, Mitrovica, Lambeck.

    A nice description of concepts:

    http://www.homepage.montana.edu/~geol445/hyperglac/isostasy1/

  30. 130
    Lynn Vincentnathan says:

    #127, thanks, David….although I couldn’t use this for my presentation, I did tell the group that they could ask any (stupid) question they wished on this blog, and get a good answer, that even some grammar school kid had asked questions and got replies.

  31. 131
    Nick O. says:

    Re #118 and #127: Although change in ice loading, following climate change, may not be thought of as a likely source of seismic events, climate change could be the cause of bigger, more intense storm systems, leading to major movements in eroded sediment. Where these movements occur across susceptible fault lines, overlying crust of the right temperature range and plasticity, then seismic response may be quite likely, in fact, rather than not. For a useful discussion, see:

    Westaway R
    Investigation of coupling between surface processes and induced flow in the lower continental crust as a cause of intraplate seismicity
    EARTH SURFACE PROCESSES AND LANDFORMS 31 (12): 1480-1509 OCT 30 2006

    Of course, it’s not simply climate change that can cause sediment movement of the scale and extent of this kind: the ‘Three Gorges’ dam provides an interesting encounter with the sediment-seismicity effect, although in this instance, the chinese have probably been particularly lucky, in that the crust is fortuitously v. resistant in this region to the effect in question. It won’t be everywhere, though, so the seismic effect problem shouldn’t be ignored.

  32. 132
    Lynn Vincentnathan says:

    RE #130 & “climate change could be the cause of bigger, more intense storm systems, leading to major movements in eroded sediment”

    Thanks, and you made me think of another thing. I believe if there is enough sea warming and pockets of ice-bound methane & gravel melt (thermokarst??), this also leads to some undersea landslides, and perhaps quakes (which might then mechanically release more methane & ice), if not volcanic activity.

    I’m way over my head here, but I’m trying to understand.

  33. 133
    David B. Benson says:

    Lynn Vincentnathan (129) — You are welcome. The situation is better explained, but at greater length, by Martin Vermeer in comment #128 and Nick O. in comment #130. I will point out that the induced earthquakes due to isostatic effects or massive erosion, etc., tend to be minor. The major and great earthquakes can only be powered by tectonic plate flow, although the exact timing can probably be altered by adding or subtracting ice.

    There is one enigmatic fault in northern Sweden, still occasionally moving, which first greatly moved ‘shortly’ after the fennoscandinavian ice sheet had largely melted away. This seems to suggest a locked, deep fault which removal of a few percent of the overburden sufficed to cause it to move. But little is understood about such intraplate faults, so it might have had a different primary cause.

  34. 134
    Ray Ladbury says:

    Jim Cripwell, Looking over your posts, I can only conclude that somehow Realclimate has established communications with a being on another planet. Wow! The mind boggles. First, on your planet it would appear that climate and weather are indistinguishable (per your comment in #85). Indeed, the sun does drive weather for the most part here, too, but there are other important forcers as well. It is also interesting that on your planet CO2 is a “very minor” ghg, whereas here it is responsible for >20% of the 33K greenhouse effect. Or do you consider >20% “very minor”? However, it would appear that on your planet, the understanding of planetary atmospheric energetics lags behind that on our planet by at least 50 years! The greenhouse effect is well understood by scientists even if it is not understood by you. Finally wrt solar cycles, yes, it looks like solar cycle 24 will be a bit wimpy (a boon for my satellites), but I still wouldn’t put it outside the normal range just yet. The 11-year solar cycle with 7 years solar max and 4 years solar min is an idealization. What is more, what the Sun does in the next solar cycle is irrelevant, as the past 3 solar cycles were sufficient to demonstrate the divergence between solar activity and climatic trends. What that means is that there has to be an additional forcer, so even if we saw an effect due to a really wimpy SS 24, it would not weaken the case for anthropogenic causation of the current warming epoch.
    BTW, re your characterization of CO2 as “very minor” I question not just its veracity, but also the style. To quote Mark Twain: “Substitute “damn” every time you’re inclined to write “very”; your editor will delete it and the writing will be just as it should be.”

  35. 135
    Alex says:

    I wonder why these scientists bothered responding to the survey, apparently without caring who’s behind it. It’s clear that there are operations out there willing to manipulate, misrepresent, cherry-pick, and/or misinterpret findings. You’d think that would justify some caution.

  36. 136
    Jeffrey Davis says:

    re: solar cycles

    The mean variation between cycles is much less than the variation within a cycle. If there were a pronounced solar effect due to changes in output it would track the rise and fall of output within the cycle, and the temperature record would show a rise and fall like a sine wave or a little roller-coaster. The temperature record has no little sine wave which tracks the solar cycle rise and fall.

  37. 137
    Timothy Chase says:

    Alex (#135) wrote:

    I wonder why these scientists bothered responding to the survey, apparently without caring who’s behind it. It’s clear that there are operations out there willing to manipulate, misrepresent, cherry-pick, and/or misinterpret findings. You’d think that would justify some caution.

    People tend to expect others to be like themselves.

    If they are honest, their first impulse is to be trusting, forthcoming, and if of good will, to expect good will in return. It is only with experience that honest people will become more careful. Speaking from experience, I didn’t really understand what people could be like until a young lady I had a crush on came back from Shellback Initiation. (We were both in the navy and onboard ship at the time – and the ship crossed the equator.)

  38. 138
    Pete Dunkelberg says:

    OT: Open Lab 2007

    http://pandasthumb.org/archives/2007/11/openlab-2007-su.html

    Follow the url. Nominations are being taken for OpenLab 2007. I would like to see something about climate change included, but I don’t know what to pick.

    Note: in this situation it is fine for a blogger to submit his or her own best. Who else knows your whole work?

    p.s. you still have a month to write the greatest. What do you want people to understand?

  39. 139
    dhogaza says:

    wonder why these scientists bothered responding to the survey, apparently without caring who’s behind it.

    Most didn’t, apparently, only 50+ answered it.

  40. 140

    Climate scientists have always amazed me and continue to do so more every day.Its always surprise and i dont know how they are able to do it.

  41. 141
    Jim Cripwell says:

    Ref 134 Ray writes “What is more, what the Sun does in the next solar cycle is irrelevant” We will see. We only have about 6 or 7 years to wait.

  42. 142
    Jim Cripwell says:

    Again Ref 134. I quote from a dialogue between Fred Singer and Gavin Schmidt from the BBC and Richard Black.

    “Sceptic The natural greenhouse effect keeps the Earth’s surface about 33C warmer than it would otherwise be. Water vapour is the most important greenhouse gas, accounting for about 98% of all warming. So changes in carbon dioxide or methane concentrations would have a relatively small impact. Water vapour concentrations are rising, but this does not necessarily increase warming – it depends how the water vapour is distributed.

    Counter
    Water vapour is essentially in balance with the planet’s temperature on annual timescales and longer, whereas trace greenhouse gases such as CO2 stay in the atmosphere on a timescale of decades to centuries. The statement that water vapour is “98% of the greenhouse effect” is simply false. In fact, it does about 50% of the work; clouds add another 25%, with CO2 and the other greenhouse gases contributing the remaining quarter. Water vapour concentrations are increasing in response to rising temperatures, and there is evidence that this is adding to warming, for example in Europe. The fact that water vapour ”

    It seems to me that this illustrates very vividly why the discussion between the two sides is a dialogue of the deaf. We know both men are honorable scientists who would not make such statements if they could not back them up. Yet when Gavin states “The statement that water vapour is “98% of the greenhouse effect” is simply false.”, something is radically wrong. Would it not be a good idea to get to the bottom of this particular disagreement in a thoroughly scientific and professional way?

    [Response: That's the thing about science, some things are simply incorrect. There is no compromise possible. Singer uses the 98% number because it sounds good, he doesn't care that it is false. See http://www.realclimate.org/index.php/archives/2006/01/calculating-the-greenhouse-effect/ for instance. -gavin]

  43. 143

    Re #133 David, you are right that earthquakes seen as a consequence of isostatic load changes tend to be small (and about vulcanism I don’t dare to say anything — not my field. I suspect the same applies).

    However! Our only experiences with changes in isostatic load tend to be small, like the filling of hydro-power reservoirs, mountain glacier retreat etc. If the whole Greenland ice sheet, or a large part of it, were to go on a decadal timescale, we might see some biggies… nobody knows. But I expect that then the direct consequences of sea level rise would steal the limelight ;-/

  44. 144
    catman306 says:

    143, 133: What bothers me about melting glaciers and ice sheets are the the changes in angular momentum caused when many millions of tons of ice are removed from mountains 10,000 feet high and drained to the seas. Any rotating system will experience vibrations and stresses as mass shifts. For the earth, those shifts in mass may open faults or cause them to move: earthquakes. Had your tires balanced lately?

  45. 145
    John Finn says:

    Re: Gavin’s respoonse to #96

    This is great. Despite the fact that the trends are well explained by our current understanding of increasing GHGs and their effects, you prefer to put faith in an unmeasured, undetected, unphysical ’something’ that might (or might not) have something to do with the sun.

    But the trends are not well explained. The mid-20th century warming cannot be explained without including the aerosol fudge factor. The regions which produced aerosols in the post-war period covered less than 10% of the NH. If global temps fell be 0.2 deg C between 1940 and 1970 then temperatures in the aerosol-producing regions must have fell by at least 2 degrees – possibly a lot more since they need to overcome the global warming from CO2.

  46. 146
    John says:

    Nick @123 – thanks for the explanation. At least I know know what everyone means when thesewords get bandied around. Couple of observations though :
    1) it seems to be a chicken and egg situation – the amount the earth radiates is a function of the average surface T. The temp rise could come from other sources as well as absorbtion and re-radiation. It doesn’t have to be due to gases right ?
    2) Just doing a quick calculation. A 3.7 W/m2 increase seems quite large. I just worked out that this would be what we would get if the earth was 1 million km nearer the sun. Tha seems a lot to put onto a gas we can only measure in ppms – is this possible ? Does the physics show that an extra 280 ppm (doubling) gives the same impact as moving 1 million km nearer the sun ?

    Thanks
    John

  47. 147
    Timothy Chase says:

    Jim Cripwell (142) wrote:

    Again Ref 134. I quote from a dialogue between Fred Singer and Gavin Schmidt from the BBC and Richard Black. … We know both men are honorable scientists who would not make such statements if they could not back them up.

    Jim, feel free to trot out any argument of Fred Singer’s you like and we can consider it separately from the man himself. However, since you have claimed that he is an honorable scientist, I consider myself obliged to point out:

    1. Fred Singer has been a hired gun for the tobacco industry with ties to Phillip Morris.

    Please See:
    S.Fred Singer – SourceWatch
    http://www.sourcewatch.org/index.php?title=Fred_Singer

    2. He has worked for Exxon, Texaco, Arco, Shell and the American Gas Association. (ibid.)

    3. Fred Singer is/has participated in thirteen organizations which receive money from Exxon. These include the Heritage Foundation ($585,000 since 1998) which he served as a policy expert in the 1980s, the Heartland Institute (they have received $791,000 since 1998) which he serves as an expert, and the Frontiers of Freedom Institute and Foundation (they have received $1,037,000 since 1998) which he serves as an Adjunct Fellow.

  48. 148
    dhogaza says:

    We know both men are honorable scientists…

    Sorry, Jim, the evidence is strong that only one of those two is “honorable”, if you consider lying to be dishonorable, which I presume you do.

  49. 149
    Ray Ladbury says:

    Re: 142. Sorry Jim, Can’t go there with you on Singer as a credible source. Anybody who takes Tobacco money to advocate that second hand smoke is not a hazard loses credibility in my book. His Oil industry conections also mitigate against his objectivity. One way to get a very conservative estimate of the effect of CO2 is to remove it from the models and look at the effect–an approach that leads to 12-15% contribution, and that neglects important feedbacks. Even Lindzen has never advocated anything less than ~6% for CO2–a number he’s never justified either by the way. I can only conclude that you and Singer live on the same planet–and it ain’t Earth.
    As far as solar influences go, you missed my point. The fact that the trend in the past 30 years has run counter to any solar trends suggests there must be something else going on–got any candidates other than anthropogenic ghg?

  50. 150
    David B. Benson says:

    Martin Vermeer (143) — I agree that little is known about intraplate faults. However, ancient faults, thought to be inactive now, which break the surface leave evidence for the magnitude. I know of only two great faults thought to be associated with the deglaciation after LGM. As one of these is in a tectonically active area (Western Washington), I take this to be an interplate fault triggered by ice removal and isostactic rebound. The other, in northern Sweden, remains enigmatic.

    It seems improbable that a large portion of the Greenland ice sheet should melt in mere decades. Nonetheless, the possibility for a major or great earthquake exists in Greenland, at any time, since (no surprise) little is known about the geology there.


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