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Unforced variations: Sept. 2013

Filed under: — group @ 2 September 2013

This month’s open thread… Expect pre-IPCC report discussion (SPM due on Sep 27, full report (pre-copy-editing) Sep 30th), analysis of this years Arctic ice cover minimum, and a host of the usual distractions.


296 Responses to “Unforced variations: Sept. 2013”

  1. 1
    gws says:

    N. Scafetta produced another of his “the planets drive climate change” papers (?), this time in the highly reputable Earth Science Reviews journal. Sad. Although probably addressed many times before, I hope you guys find some time to file an “official” rebuttal?

  2. 2
    AJ says:

    I would be interested in an honest discussion revolving around the many recent observations that contradict climate modeling methodologies and mechanisms. For instance, last week’s paper in Nature Climate Change (Fyfe, Gillet, and Zwyers, link below), illustrates how inaccurate the predictions have been over the past 20 years, and offers a number of mechanisms that may have been modeled or neglected inappropriately. Given the significance of the upcoming IPCC report and the equivalent significance of recent observations and work which may not be included in this report, a discussion of modeling paradigms, and usefulness is necessary, I think.

    http://www.nature.com/nclimate/journal/v3/n9/full/nclimate1972.html?WT.ec_id=NCLIMATE-201309

    [Response: Conflating a model-observation mismatch with a 'contradiction of climate modeling methodologies and mechanisms' is a huge (and unjustified) leap. But this issue requires a little more explanation than I can over in a comment. Wait for the post. - gavin]

  3. 3
    Russell says:

    Given the disastrous state of national politics, it seems a shame to waste hurricane names on politicians.

    Congressional aides and science advisors who morph into lobbyists seem equally deserving, and ll manner of phenomena might be rechristened in their honor.

    Retreating glaciers,for instance, leave behind Morano Moraines .

  4. 4
    Ed Davies says:

    Is there any information on what was happening to deep ocean temperatures from the mid 1940s to the mid 70s? Obviously, what I’m wondering is if there’s any connection between the surface cooling during that period and the current minimal surface warming.

  5. 5
    Dave123 says:

    Back in 2008 Ray took apart a modeling effort by Spencer based on only natural variation. http://www.realclimate.org/index.php/archives/2008/05/how-to-cook-a-graph-in-three-easy-lessons/
    One of the lines of discussion had to do with heat turnover in the ocean compartment.

    “Lesson Two: Use a completely unrealistic mixed layer depth. OK, so we’ve goosed up the amplitude of the temperature signal to where it looks more impressive, but the wild interannual swings in temperature look completely unlike the real thing. What to do about that? This brings us to the issue of mixed layer depth. The mixed layer depth determines the response time of the model, since a deeper mixed layer has more mass and takes longer to heat up, all other things being equal. The actual ocean mixed layer has a depth on the order of 50 meters. That’s why we got such large amplitude and high frequency fluctuations in the previous graph. What value does Roy use for the mixed layer depth? One kilometer. To be sure, on the centennial scale, some heat does get buried several hundred meters deep in the ocean, at least in some limited parts of the ocean. However, to assume that all radiative imbalances are instantaneously mixed away to a depth of 1000 meters is oceanographically ludicrous.”

    Since we are now attributing with good evidence surface temperature progress to distribution of heat from 700 to 2000 meters, should we revise this section of the analysis to correspond? I suspect the wild interannual swings are nonsense whether the heat stays at the surface or there are episodic deep mixing from wind and ENSO, but I don’t have the skills to go after this.

  6. 6
    Watcher says:

    Whoa there Gavin. I agree that this topic is too broad to cover in a comment, and I’m happy to await a post; but your statement simply has to be false on the face if it.

    Speaking very generally (i.e. across all of science, not just climate modelling), a model-observation mismatch arising from a properly designed experiment is absolutely crucial to address, since it bears directly on the ‘correctness’ of a hypothesis/theory. Frankly, it’s the only thing of any importance that bears on said theory. Thanks to Google it’s easy to find the relevant quote from Feynman:

    It doesn’t matter how beautiful your theory is, it doesn’t matter how smart you are. If it doesn’t agree with experiment, it’s wrong.

    [Response: Read up on Quine and the issue of auxiliary hypotheses. In practice, all theories are 'wrong' (as they are imperfect models of reality), and all tests involve multiple hypotheses. Judging which one (or more) are falsified by a mismatch is non-trivial. I have no problem agreeing that mismatches should be addressed, but wait for the post. - gavin]

  7. 7
    sidd says:

    Levitus et al., GEOPHYSICAL RESEARCH LETTERS, VOL. 39, L10603, doi:10.1029/2012GL051106, 2012

    has ocean heat content to 2000m since the late 50s

  8. 8
    Ed Davies says:

    Thanks sidd, that’s paywalled but the main graph is reproduced in

    http://pielkeclimatesci.wordpress.com/2012/04/22/comment-on-ocean-heat-content-world-ocean-heat-content-and-thermosteric-sea-level-change-0-2000-1955-2010-by-levitus-et-al-2012/

    Seems that the oceans were losing heat in the mid to late 1960s which surprises me.

  9. 9
    prokaryotes says:

    I recently added

    The so called self-preservation phenomenon has been intensively studied by Russian geologists starting in the late 1980s.[11] This metastable clathrate state can be a basis for release events of methane excursions, such as during the interval of the last glacial maximum.[12] A study from 2010 concluded with the possibility for a trigger of abrupt climate warming based on metastable methane clathrates in the East Siberian Arctic Shelf (ESAS) region

    Link

    Hank and others, do you have something to add or a suggestion to make? This is currently filed under “Related mechanism: dissolved methane release”. Further could the article be improved in other parts.

  10. 10
    prokaryotes says:

    I just looked at the nature study (linked #2), this appears to further explain the deep ocean heat content observation through ARGO.

    A new study published on May 10, 2013 in the journal Geophysical Research Letters has discovered that deep ocean waters below 700 meters (2,300 feet) have heated up unexpectedly since the year 2000.

    Link

    Which corresponds with the subsiding of the El Nino phenomenon 98/99. Link

  11. 11
    Watcher says:

    Gavin,

    I think we are in violent agreement :-). My use of quotes around ‘correctness’ alludes to the same metaphysical interpretation of theories as your use of quotes around ‘wrong’; i.e. none are strictly correct, and thus all are strictly wrong. I guess I’m just a glass half full kind of guy, and interpret ‘correct’ as meaning ‘useful to predict things in the real world’.

    [Response: Ah. Being "correct" in my definition is very different from being "useful". I'm a strong proponent of the latter despite the absence of the former. - gavin]

  12. 12
    Steve Fish says:

    Re- Comment by Ed Davies — 2 Sep 2013 @ 11:29 AM

    Free PDF here- ftp://kakapo.ucsd.edu/pub/sio_220/e03%20-%20Global%20warming/Levitus_et_al.GRL12.pdf

    Steve

  13. 13
    prokaryotes says:

    Thanks Steve, here is a quick post based on the recent papers and OHC.

    Money quote’s

    even if greenhouse gas emissions were halted today than regardless of the residence time of the carbon dioxide in today’s atmosphere, the ocean would continue to heat the atmosphere

    [..]
    Heat may have been stored at ocean depths exceeding 2000 m during the observational period we are studying and may be of significance for earth’s heat balance.
    [..]
    We have estimated an increase of 24 x 10^22J representing a volume mean warming of 0.09C of the 0–2000 m layer of the World Ocean. If this heat were instantly transferred to the lower 10 km of the global atmosphere it would result in a volume mean warming of this atmospheric layer by approximately 36C (65F).</blockquote

  14. 14
    Hank Roberts says:

    > prokaryotes … a study from 2010
    You continue to cite this same 2010 article
    Science 5 March 2010:
    Vol. 327 no. 5970 pp. 1246-1250
    DOI: 10.1126/science.1182221
    as though it documented rather than assumed the possibility of a problem.
    That paper says that someone should go look into the possibility.

  15. 15
    Hank Roberts says:

    > prokaryotes … a study from 2010
    You continue to cite this same 2010 article
    Science 5 March 2010:
    Vol. 327 no. 5970 pp. 1246-1250
    DOI: 10.1126/science.1182221
    as though it documented rather than assumed the possibility of a problem.
    That paper says that someone should go look into the possibility.

    Specifically from the supplement:
    “hydrate destabilization causes transformation of solid CH4 crystals into free gas fraction which is accompanied with increase in volume up to 150-200 times.”

    Assuming there is a shallow hydrate, they then say, well, if so ….

  16. 16
    Doug says:

    Is it just me, or do the deniers wait for the new unforced variation thread to come out each month, so that they can get their talking points in among the very first comments? Well, if it is just my imagination, it won’t be for long, now that I’ve given them this idea.

  17. 17
    Joe says:

    Maybe the answer to my question about the new paper by Kosaka and Xie (2013, Nature, doi:10.1038/nature12534) will be obvious to an expert.

    How do exactly do Kosaka and Xie fix their sea surface temperatures? The paper says that they adjust the sensible heat flux, which as I understand it is the energy transferred by (convection and) conduction from the sea surface to the atmosphere. That sounds OK.

    My question is what they do with this flux? When the SST must be cooler than the models would otherwise show is the heat from the sensible flux ‘disappeared’ or is it retained in the atmosphere? Or is something else happening?

    I guess that if the flux is ‘disappeared’ that would suggest that the true process maybe something like storage of heat in the ocean. If the heat is retained in the atmosphere I’m surprised there is such a strong cooling effect.

  18. 18
    Hank Roberts says:

    http://andrewgelman.com/2013/09/01/post-publication-peer-review-how-it-sometimes-really-works/

    “…just because something’s in a crap journal, doesn’t mean it’s crap; I’ve published lots of papers in unselective, low-prestige outlets. But it’s certainly no surprise if a paper published in a low-grade journal happens to be crap. They publish the things nobody else will touch.”

  19. 19
    Dave123 says:

    I don’t know whether this will help you Joe, but John Gammon wrote this analysis of Kosaka:

    http://blog.chron.com/climateabyss/2013/08/learning-from-the-hiatus/

    good luck!

  20. 20
    Susan Anderson says:

    Joe, there is no end to the tricksiness of industrial-strength falsehood. We just have to soldier on and ignore it afaik. Reacting just makes it worse.

  21. 21
    Pete Dunkelberg says:

    Gone?
    http://data.giss.nasa.gov/gistemp/graphs/
    Gone

    The requested resource
    /gistemp/graphs/
    is no longer available on this server and there is no forwarding address. Please remove all references to this resource.

    WhyoWhy?

    Is there a replacement?

    [Response: http://data.giss.nasa.gov/gistemp/graphs_v3/ - gavin]

  22. 22
    prokaryotes says:

    Estimating northern polar CH4 flux

    I collected some interesting papers, as always constructive feedback is welcome.

  23. 23
    Tony Weddle says:

    Interesting analysis of the new RCPs, by Dave Cohen. I have to agree with him and think there are even more assumptions in there that are unwarranted, or at least unvalidated, like the amount of coal, natural gas and oil that are available (at required extraction rates) to produce some of the emissions projections for some or all of the pathways. But the notion that economic growth can keep rising to 2100 under all emissions scenarios is a humdinger.

  24. 24
    SecularAnimist says:

    Tony Weddle wrote: “But the notion that economic growth can keep rising to 2100 under all emissions scenarios is a humdinger.”

    “Economic growth” is a content-free term.

    “Growth” of what?

  25. 25

    A new paper is apparently out on the Younger Dryas question. Not a lot of detail, and no link to the actual paper, but a place to start for those interested:

    http://www.cbc.ca/news/technology/story/2013/09/02/meteor-quebec-climate.html

  26. 26
    Mal Adapted says:

    Hank Roberts, in the previous UV thread, linked to John Nielsen-Gammon’s discussion of the new Kosaka and Xie paper: Learning from the Hiatus. Reading N-G’s follow-up post, I had an “Aha!” moment:

    Still, even the tropical and subtropical Pacific together constitutes a fairly small fraction of the globe. For the rest of the story, please see one of my favorite underappreciated climate papers: Compo and Sardeshmukh (2009). They showed that global land surface temperatures have warmed not as a direct response to increased Tyndall gases and other local radiative forcing agents, but instead in response to changing sea surface temperatures. The warm ocean heats the air above it, which eventually moves over land, but also pumps water vapor into the atmosphere, and the water vapor is the primary agent altering the radiative balance over land. So the chain of events is radiative forcing –> ocean temperatures –> water vapor –> land temperatures.

    That’s the first time I’ve seen land surface warming explained that way. Has it been so stated on RealClimate before, and I missed it?

  27. 27
    Hank Roberts says:

    Where does this image come from originally, anyone recognize it?

    I’m looking for one with a caption showing depth below sea level marked on the vertical axis (and some discussion) — missing in the copies I’ve found with the linked image search

  28. 28

    I guess this goes under the title of usual distractions, but since you asked so politely and since its suddenly in the news again and I have spent (or wasted) another day or two looking at this, I thought I would update you on what I know about the Younger Dryas and/or Impact.

    Andrew Madden et al. have an abstract in the upcoming GSA where they claim that not only are the nanodiamonds viable quantifiable proxies, they spike in abundance at the Younger Dryas boundary and occur occasionally in lesser amounts in the record, and then reappear as a background in recent times. So far so good. Then the recent spherule analysis reveals a composition that could put it very near Corossol. I have discovered that the n-diamond that Madden and folks find in abundance are a relatively new development and represent a hydrogen doped variant which is easily catalyzed by hydroxylated iron and nickel at temperatures above 1000 C. So what is required is a source of iron and nickel, water or ice, and either a carbonaceous body or some limestone. They further claim the spherules put the impact very near Corossol crater in Quebec, and this crater does indeed have a limestone basement. So I further speculate that the spherules, which seem to be very sparse, could represent glacial erratic boulders and rock flour heated and quenched by the impact since the area was at the very edge of the ice sheet at the time. Amazingly a carbonaceaous impact into a thick ice sheet could presumably also do this (as in Black Sturgeon River in the Nipigon basin), but I am still putting that hypothesis on the side unless further quantifications increase the scale of this event vastly. Clearly also Corossol crater could not necessarily cause the Younger Dryas, but it was going to happen anyway as we know Glacial Lake Agassiz to Gulf of Mexico discharge stopped at 13 ka BP and so it is possible to theorize an event like this, even more so if it hit an ice sheet first, could trigger the even through possibly positive sea ice feedback with weak atmospheric anomalies over a few years or a decade, and those effects including ozone could have put additional stresses on already at risk megafauna.

    I do hope that puts things in a better perspective.

  29. 29
  30. 30
    Hank Roberts says:

    Memo to self:-)

    At Andrew Gelman’s blog on research and statistics, a developing discussion continues to be interesting: Evaluating evidence from published research
    While the examples are from social science, the thinking is relevant to discussion about climate, and about the need to think hard before reblogging.

    You can lend your credibility to others’ work
    You can reduce your own credibility by reblogging without weighing evidence.

    Like heat, credibility flows both ways.

  31. 31
  32. 32
    prokaryotes says:

    Hank, the image is from this 2010 slide.

  33. 33
    Killian says:

    Re: 23 Mal Adapted said, Hank Roberts, in the previous UV thread, linked to John Nielsen-Gammon’s discussion of the new Kosaka and Xie paper: Learning from the Hiatus. Reading N-G’s follow-up post, I had an “Aha!” moment:

    Still, even the tropical and subtropical Pacific together constitutes a fairly small fraction of the globe. For the rest of the story, please see one of my favorite underappreciated climate papers: Compo and Sardeshmukh (2009). They showed that global land surface temperatures have warmed not as a direct response to increased Tyndall gases and other local radiative forcing agents, but instead in response to changing sea surface temperatures. The warm ocean heats the air above it, which eventually moves over land, but also pumps water vapor into the atmosphere, and the water vapor is the primary agent altering the radiative balance over land. So the chain of events is radiative forcing –> ocean temperatures –> water vapor –> land temperatures.

    That’s the first time I’ve seen land surface warming explained that way. Has it been so stated on RealClimate before, and I missed it?

    This is an excellent insight and, at least intuitively, makes sense given the heat content of water and the hydrological cycle. Fits well with the deep ocean info coming out the last year or two.

    If other researches support this outcome, it’s a perfect explanation for the silly “pause” discussion.

  34. 34
    prokaryotes says:

    Re Methane Hydrate feasibility

    The so called japan breakthrough

    From June to July, the pressured core samples were acquired from methane hydrate layers. In this operation, a flow test through dissociation of methane hydrate was begun on March 12 after the preparatory works including drilling and installing equipments. JOGMEC has been conducting gas production until now.
    However, it ended the flow test today on March 18 since changes in well situation, including tentative malfunction of the pump to draw water for depressurization and simultaneous increase in sand production, have been seen and a rough weather was forecasted.

    Link
    An older article:

    “When the temperature rises or the pressure drops, one cubic foot of methane hydrate ice can release 160 cubic feet of gas,” he explains. “Forces from methane hydrate dissociation have been blamed for a damaging shift in a drilling rig’s foundation, causing a loss of $100 million. Oil and gas drilling companies are more interested in protecting their drilling equipment than harvesting the hydrates as an energy resource, at least for the next 10 years.”

    Link

    I don’t have the news now but at least 1 company (starting with the letter G – not Gazprom) stopped methane hydrate exploration, i think this is all hype and risky.

  35. 35
    Tony Weddle says:

    SecularAnimist, “economic growth” means growth of the economy, usually measured by GDP, as given in the RCPs.

    It is a big assumption that GDP can continue to grow through 2100, and a rapid rate of growth for RCP2.6. Economic growth is difficult enough now, with some resources nearing the state of being scarce. With that and with climate change causing plenty of damage (both ecologically and economically) over the next decades, economic growth at all seems like a huge assumption. But I guess it’s a way to sell RCP2.6.

  36. 36
    prokaryotes says:

    This is just in the news…

    Japan’s energy savior?

    Revised estimates, based on data collected over the last year and released last week, say there are massive deposits of methane hydrate below the Sea of Japan. These will be easier to reach than most gas deposits as they are located close to the seabed surface, officials say. Methane hydrates are believed to collect along geological fault lines, and Japan sits atop a nexus of three of the world’s largest deposits.

    “Although methane is a cleaner-burning fossil fuel than coal or oil, the as-yet untapped methane hydrates represent ‘captured’ greenhouse gasses that some believe should remain locked under the sea. The mining of methane ice could also wreak havoc on marine ecosystems.”

    Yamamoto disagrees that there is any danger of such blowouts or major environmental damage — although a small methane hydrate blowout was linked to the BP spill in the Gulf. Larger releases of methane from clathrate beds throughout history, known as the actions of a “Clathrate gun,” have been responsible for mass extinction events.

    Researchers do not agree on the risks associated with methane hydrate exploration for commercial energy use. Oceanographer and Rice University professor Gerald Dickens agrees with the Japanese research team, arguing that there is little danger of such catastrophes coming from human action.

    “The only potential issue in regards to drilling would be if there is greatly over-pressured gas immediately beneath the gas hydrate,” Dickens says. “However, there is growing belief and rationale to suggest that this cannot occur in nature. So, as far as drilling is concerned, there should be no issue.”

    Tim Collett of the United States Geological Survey, a leading expert on methane hydrate, believes it is possible that both natural and human induced changes can lead to hydrate destabilization, triggering catastrophic landslides.

    “Evidence implicating gas hydrates in triggering seafloor landslides has been found along the Atlantic Ocean margin of the United States and off northern Europe,” he told the U.S. Congress in 2004. “These processes may release large volumes of methane to the Earth’s oceans and atmosphere.”

    Link

  37. 37
    Mal Adapted says:

    Hank, thanks. I knew all the underlying physics, I just never put it together like that. Now that I have, it’s obvious 8^}!

  38. 38

    Just a quick update on the presumed YD impact, Andrew Madden has quantified nanodiamonds in recent sediments and they appear to be viable impact proxies, huge amounts of n-diamond at the YD boundary. n-diamond is a relatively recent development, hydrogen doped and synthesized in large quantities by hydroxylated iron and nickel catalysts in the presence of carbon, and Corossol has a limestone basement. So I’m calling it. And if that doesn’t work out or if they require something even larger, they still do have a viable ‘Plan B’ – the Black Sturgeon River basin.

    Unless something changes dramatically, I’m finished with this thing.

  39. 39
    Tom Adams says:

    “…methane hydrate exploration, i think this is all hype and risky.”

    Japan produced 4 million cubic feet in their 1st production run at twice the projected rate.

    Do you mean economically risky? This is government not private research at this point. Japan thinks the status quo where they produce only about 1/1000 of the liquid fuels is risky for a nation state.

  40. 40
    0^0 says:

    Anybody having checked what Svensmark has been up to lately?

    http://www.dtu.dk/english/News/Nyhed?id={ABB2F1B4-F5F7-4452-BB39-9818EA7CB8F9}

    Any comment?

  41. 41
    David B. Benson says:

    Kevin McKinney @25 & Thomas Lee Elifritz @28&38 — Thank you. It certainly looks like there was a Clovis Impactor.

  42. 42
    David B. Benson says:

    West Antarctica Ice Sheet Existed 20 Million Years Earlier Than Previously Thought
    http://www.sciencedaily.com/releases/2013/09/130904141054.htm
    which resolves a ice mass discrepancy.

  43. 43
  44. 44
    AIC says:

    Re Unforced Variations #446 last month:

    Thank you, Mike.
    I have your “Dispatches” book.

    I’m hoping people will get more involved in, for example, the Comments or Discussion online for many news articles. Some statements are made by the other side that look like they would be easily refuted or debunked by somebody knowledgeable.

  45. 45
    prokaryotes says:

    I mean it is not feasible because of economical and environmental reasons.

    Environmental risks: excessive methane and landslides pose serious questions – Before full-scale production of methane hydrates can begin, studies must also be carried out to analyse risks such as the destabilisation of the sea floor, which could cause underwater landslides, and potential greenhouse gas leaks.

    Many geologists believe that the wrong drilling method could destabilise the seabed, causing vast amounts of sediment to slide miles down the continental slope, devastating marine life and even leading to deadly tsunamis. JOGMEC’s engineers used a depressurisation method to extract methane gas from hydrates earlier this year by setting an electric submersible pump in a drilled hole and bringing the water to the surface to decrease hydro-static pressure.

    Another key environmental concern for producing methane hydrates is the potential for greenhouse gas leaks. A report by the Climate Energy Institute in 2012 notes that methane itself is a greenhouse gas which is 100 times more damaging than carbon dioxide, and scientific studies are showing that the gas has already started to “bubble and hiss” out of oceans and soils in the Arctic, leaking into the atmosphere and contributing to global warming.

    Japan hopes commercial quantities of methane gas from hydrates will be produced from 2018, but the feasibility of extracting the fuel is still at a very early stage of development.

    Link

    Reservoir simulation for gas hydrates does not yet accurately incorporate advanced geomechanics concepts. Thus, one risk factor that remains to be assessed is the potential for gas migrating away from a dissociating, high saturation gas hydrate deposit to find an existing fracture or to cause a new fracture to form in an overlying, relatively impermeable layer. Such a scenario might lead to unintended leakage of methane into other sediments or even emission of methane at the surface (Rutqvist and Moridis, 2010).

    Link

    While Canada has decided it isn’t feasible to make further investments in the field, methane hydrate research is strategic for Japan. Exploiting the abundant methane hydrate deposits near its coast would allow Japan to end its foreign energy dependency, with enough recoverable gas to meet its power demands for 100 years.

    Japanese researchers are working toward establishing commercial extraction operations for some of these deposits by 2019.

    Link

    Archer et al. 2009

    The steady-state inventory of methane in both global models exhibits a similar sensitivity to uniform offsets of the temperature of the ocean, as did its predecessor model (3). A warming of 3 °C is sufficient to reduce the steady-state inventory by more than half in either model.

    We expect the hydrate column model to systematically underestimate the amount of methane in high concentration deposits. Selective deposition of hydrate in sandy sediments would increase the hydrate concentration there. Gas migration may be facilitated by faults and channels in the sediment column.

    Link

    If you extract methane hydrate you create a channel, if anything goes wrong (and things tend to go wrong) methane blow outs at boreholes are likely or through fracturing and overall compromise in deposit integrity.

    The extracted methane hydrate is replaced with ocean water – which will warm the deposit and change pressure over time and space, hence we can expect similar effects as we observe from hydraulic fracturing.

    Related

    Seismicity induced by fluid extraction Based on the Mohr-Coulomb argument that injection of fluid brings rocks closer to failure, it may seem counter-intuitive that seismicity could also result from fluid extraction. Instead, one might expect that the decrease of pore pressure should inhibit failure. This effect does indeed exist. It is particularly important if pre-existing faults are in immediate contact with the reservoir and subject to a spatially heterogeneous decrease in pore pressure (Pennington et al., 1986).

    As a consequence of fluid extraction, strain accumulates either due to differential compaction or continued aseismic slip of nearby portions of the fault which builds up stress along the locked portions of the fault. Eventually, the accumulated stress will exceed the strength of these asperities and be released in the form of an earthquake. The process is expected to repeat itself as long as the pore pressure continues to decrease along the active fault. An important prediction of this model is that the magnitude of earthquakes should increase over time (Pennington et al.,1986).

    Link

  46. 46
    0^0 says:

    Regarding Svensmark.. I guess what they now did was a bit larger scale experiment than already discussed over here some years ago http://www.realclimate.org/index.php/archives/2006/10/taking-cosmic-rays-for-a-spin/ but still nothing in any way convincing

  47. 47
    BillS says:

    Re: Watcher, #6

    “All models are wrong, some are useful” (paraphrase Geo. Box)

    “All models are right, most are useless” (Thaddeus Tarpey)

    and the conclusion of our faux syllogism is:

  48. 48
    Edward Greisch says:

    Air Pollutants and the “Warming Hole” of America
    http://blog.epa.gov/science/2013/09/air-pollutants-and-the-warming-hole-of-america/

    Part of the source of denialist rhetoric about recent warming?

  49. 49
    MARodger says:

    Another month with the annual rise in atmospheric CO2 way above 2ppm during ENSO-neutral conditions. Annual MLO rise to July 2013 – 2.97ppm.

  50. 50

    “…and the conclusion of our faux syllogism is:”

    …let’s see Theo box George.


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