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Comments 36351 to 36400:

  1. LazyTeenager at 22:46 PM on 31 May 2014
    The Wall Street Journal denies the 97% scientific consensus on human-caused global warming

    Weeeelll , I think we should defer to the expertise of Anthony Watts. Just compare the number of peer reviewed papers he asks his minions to disparage, to the number of peer reviewed papers he asks them to applaud. I am taking bets the ratio is close to 97%.

  2. Global warming and the vulnerability of Greenland's ice sheet

    The problem with the IPCC reports is that they are biased to be too conservative.  If they were literally, mathematically unbiased, half the time they would hit high, half the time they would hit low.  We don't see that.  Three obvious reasons are that humans tend to be biased in the conservative direction, the scientific process is biased in the conservative direction (default assumption is that nothing new is happening), and that for reasons of credibility in the face of "skeptics", I think the IPCC attempts to never overpredict.  This sort of cascaded filtering is nothing new; there are examples of companies that failed because a CEO inclined to "shoot the messenger" successfully created his own little bubble of misinformation, till reality intruded.

    But if the IPCC was literally and accurately unbiased, about half their predictions would fall short as new data arrived.  There's things where we can look and say "that won't happen" — we know the ice caps won't melt quickly in place, because physics tells us so pretty directly.  But otherwise, it would be nice to see predictions that were based on sound science, yet not artificially muted by pervasive conservatism.  (I assume this is what we're getting from Hansen, which is why he sounds so much more alarmed than the IPCC.)

  3. Global warming and the vulnerability of Greenland's ice sheet

    wili@1,

    The study in question does not try to quantify the GIS contribution to SLR nor the  prediction of its contribution (in the abstract and press releases I only have access to).

    The Antarctic study you're most likely referring to (McMillan 2014), quantifies the current total Atntarctic contribution from recent satelite altimetry as 160Gt/y, equiv. to 0.45mm (central value). Recalling the AR5 number for Antarctic ice sheet contribution: 0.27mm/y, we can clearly see that AR5 has been substantially outdated as (McMillan 2014) increases it by some 70%. We know that IPCC findings about SLR outdate quickly, so no surprise here.

    I think the increase of AIS loss rate comparing to AR5 is nothing new, considering e.g. (Hansen 2012) who predicted sustained doubling of icesheet melt rate every 7-10 years with SLR up to 5m by 2010. I think Hansen based his prediction on GIS data but I don't know the recent GIS melt data, apart its contribution is just slightly higher (0.33mm/y by AR5). AIS melt rate in (McMillan 2014) seems to be somewhat slower than (Hansen 2012) prediction, if it can be a bit of consolation. That is just my very rough interpolation: in order to verify if Hansen 2012 was correct, we need to wait a couple decades (if we are young enough).

    To put the current IS melt contribution to SLR in perspective, it's worth remembering they are still quite behind the main contributors:

    - thermal ocean expansion due to warming: 1.1 (0.8 to 1.4) mm/y

    - glaciers: 0.76 (0.39 to 1.13) mm/y

    and based on that numbers, IS will not become dominant contributor for another 20y or so, even according to somewhat overestimated prediction by Hansen.

  4. 2014 SkS Weekly News Roundup #22A

    Regarding 'Global Warming' scarier than 'Climate Change,' surveys find, I believe the blog writer is somewhat confused about the difference in the terms. Do you believe that these two are synonymous? I think that the consensus of commenters on this site is that both are happening, both are quantifiable and both portend catastrophe. Even so, these concepts are not the same thing, though the belief is that they are linked. The aforementioned article's blogger does a disservice to the climate-concerned community by suggesting at the end of the article that scientist should be aware of the different responses elicited by the different terms. I would infer that the preferred terminology would be "global warming," in order to "scare" the most people. Is this an intentioned implication, and should climate scientists make sure to be as scary as possible in their publications? If so, then they should also clearly state in their abstract that the results of the study support the consensus belief that global warming is accelerating and that is being caused primarily by human emissions of carbon dioxide?

  5. 2014 SkS Weekly News Roundup #22A

    Saw this article floating around social media the other day. My guess is it is a distortion, or at the least a distraction from Arctic collapse, but is there a more scientific response someone can point me to?

  6. Global warming and the vulnerability of Greenland's ice sheet

    I think this shows a few problems with the IPCC reports and using them as THE reference for assessments. First, new research is coming out fast, changing previous conclusions (as above) and 7 years is a long time. Then (and related) the ESLD effect might have affected estimates of ice sheets and sea level rise. IPCC AR4 was quite far off at the low side but also IPCC AR5 gave a lower value than the average expert: www.realclimate.org/index.php/archives/2013/11/sea-level-rise-what-the-experts-expect/   and www.glaciology.net/Home/Miscellaneous-Debris/comparisonofsealevelprojections

    OK, that estimates are changing with time is in principle a normal part of the scientific progress and not in itself a proof of any bias. But the tendence has been that new (dynamical) effects are added with time, increasing estimates, which is the problem with bottom-up approaches. And IPCC AR5 dismissed the semi-empirical approaches in favour of the process-based, but they now seems to be the more realistic.

  7. Global warming and the vulnerability of Greenland's ice sheet

    Thanks lots for posting this. Do we have any idea about how much this particular dynamic might increase the rate of sea level rise in the next few decades? A little? A lot? Not at all?

    If even a little, how does this, plus what we have learned about WAIS change our understanding of likely sea level rise in the next few decades and by the end of the century? This is a questions of vital concern to the hundreds of millions living in directly vulnerable areas, and really, to everyone one on earth, since nearly all will likely be affected one way or the other by the wrenching changes needed to deal with the evacuations of these areas.

    So any light anyone can throw on these questions would be most welcome.

  8. Volcanoes emit more CO2 than humans

    Your Moerner and Etiope and Kerrick links are dead.

    Moderator Response:

    [DB] Mörner and Etiope is here.  Kerrick is here.  A nice chapter on geologic methane by Etiope is here.

  9. Rapid climate changes more deadly than asteroid impacts in Earth’s past – study shows.

    Leland @30 - I know that conventionally volcanic CO2 is not considered sufficiently isotopically light to explain the strong -ve Carbon isotope excursions. So hydrates are commonly pointed to as a likely source of light carbon. Others point to the geothermal baking of organic-rich sediments releasing high volumes of light carbon. Still others point to crustal melting and mixing with plume magma generating the volumes of light carbon. We also know that the geochemistry of these deepest-mantle-derived magmas is a little different from more shallow-melted magma.

    Personally, I'm slightly skeptical of the hydrate idea as the initial driver of the ancient global warming events because the rapid, strong warming points to the initial atmospheric buildup of carbon (CO2/methane) faster than surface ocean/biosphere can buffer the changes (ie centuries to a few millennia at most). IPCC AR5 points to uncertain but expected slow (millennial-scale) release of hydrates, then slow subsequent release of methane from the sea to the atmosphere (see p 531 of the report - warning large pdf). Also recent observations suggest that microbial metabolism would mitigate ocean methane release somewhat.

    The "tripple point" shallow hydrates you refer to may indeed be more responsive, and affect the same shallow ocean reservoir that would be saturated by volcanic CO2 and geothermal methane/CO2. 

    Given the magnitude of the temperature changes observed for these ancient events and the difficulty in resolving dates under about 2,000 years, it seems likely that a cascade of knock-on effects unfolded after the initial perturbation of the system. Hydrates and permafrost methane release would - in my personal view - be triggered as a response to the initial volcanic/geothermal carbon-shock global warming. I recall somewhere related to the Permian extinction that there are multiple isotopic kicks in a very expanded geological exposure which supports the idea of various carbon reservoirs being released in sucession, but I can't find the paper right now. There was also a good paper suggesting that the Eocene hyperthermals after the PETM were driven by permafrost melting at orbital pacing (ie a long tail feedback, long after the initial carbon shock of the PETM - which I am personally convinced was triggered by the North Atlantic LIP).

    The suggestion that such huge and long-lasting feedbacks could be triggered by an initial carbon-shock of sufficient rate and magnitude (at rates similar to or slower than today) is truly scary to me.

  10. The Wall Street Journal denies the 97% scientific consensus on human-caused global warming

    Of the two or three percent of climate scientists that don't "believe" in man made global warming, how many of them don't deny it, but instead just don't think there's enough evidence yet to make the claim? In other words, we always assume that the two of three percent firmly reject man made global warming, but is that really the case? Perhaps the figure is much lower than the already very low two or three percent, that categorically reject manmade global warming. There may be a very high percentage within the two or three percent, that believe we may be behind the warming. Perhaps Skeptical Science should do a post on that. 

    Moderator Response:

    (Rob P) - See The Consensus Project (TCP) at the top of the page. Those classified as rejections include papers which minimize the role of humans in global warming and therefore ascribe the bulk of warming to other unexplained forces. 

  11. Leland Palmer at 13:51 PM on 30 May 2014
    Rapid climate changes more deadly than asteroid impacts in Earth’s past – study shows.

    howardlee @26-

    Wow, that's a great list, thanks. Best I've ever seen. :)

    So there are isotope excursions at a coincident time and in the correct direction to fit the flood basalt erruption / methane and CO2 release / oceanic acidification and anoxia general theory of most mass extinction events.

    It appears now that there is a subclass of methane hydrates that might be dramatically less stable than most methane hydrates are - high salt "triple point" hydrates. 

    DYNAMICS OF SHALLOW MARINE GAS HYDRATE
    AND FREE GAS SYSTEMS- Xaoli Liu (Thesis)

    "We show that the hydrate system at South Hydrate Ridge is already
    everywhere at the three-phase boundary, and therefore it is highly sensitive to changes in ambient conditions, offering a mechanism for rapid release of methane from gas hydrate deposits." [page 2]

    Other scientists including Peter Flemmings are starting to write about these high salt hydrates. Models of the high salt hydrates tend to confirm Xaoli Liu's predictions.

    These hydrates appear to be at the triple point of the hydrate/methane gas/sea water system. This would result in extreme temperature sensitivity and gas phase transport of methane within the high salt region. These high salt methane hydrate deposits, in combination with albedo change from loss of sea ice and permafrost rotting, could act as a bridge between mild CO2 based warming and massive hydrate dissociation.

    The high salt concentrations in these sediments would normally be diluted out by diffusion into surrounding sea water and low salt sediments. The salt is generated by the well known "purification by crystallization" process in which the methane hydrates tend to exclude salt from their crystal structure when they crystallize out, leaving the salt behind in the sediments. So, a continuous flow of methane gas from deeper in the deposit is necessary to sustain these high salt triple point hydrates, before the salt diffuses away.

    The need for a continuous flow of methane tends to put the high salt deposits in pinnacles at the top of the hydrate formations - in deposits at the top of the hydrate stability zone. So the relative shallowness of these deposits may make them more vulnerable to temperature changes.

    These high salt deposits are in principle detectable by seismic mapping - there is a blank looking "wipeout zone" created by free diffusion of gas beneath a methane producing pinnacle. 

    So, just by looking again at existing sonic mapping data, we could in principle discover just how common these high salt methane hydrate deposits are, and determine how likely they are to push the climate system past tipping points into low level (?) runaway global warming.

  12. Rapid climate changes more deadly than asteroid impacts in Earth’s past – study shows.

    Thanks howardlee

  13. Joel_Huberman at 09:57 AM on 30 May 2014
    Rapid climate changes more deadly than asteroid impacts in Earth’s past – study shows.

    Thanks to billthefrog @ 11 and howardlee @12 for their helpful, informative responses to my comment about the Snowball Earth web site @ 10. And thanks to everyone @1-27 for a wealth of fascinating information about paleoclimatology!

  14. 2014 SkS Weekly News Roundup #22A

    ubrew12: You seem to have missed the point of the article and the purpose of the two surveys it summarizes. 

  15. The Wall Street Journal denies the 97% scientific consensus on human-caused global warming

    Kernos - Wikipedia has a list here. You will note a preponderance of non-climate scientists in that list as well as a large no. who have "gone emeritus". Inside that list, I would say only Lindzen, Spenser, Christy, and Chylek have any scientific chops in the field worth considering. I dont think any of these 4 are into denying physics, though some of the "natural causes" arguments push Conservation of Energy pretty hard. I also do not think that they have published hypotheses that have not been discredited in the published literature. Corrections welcome.

  16. 2014 SkS Weekly News Roundup #22A

    Reading that LiveScience article ('Global Warming' scarier than 'Climate Change,' surveys find) I got the distinct image of people rearranging the deck chairs on the Titanic.

  17. Anthony10658 at 06:17 AM on 30 May 2014
    The Wall Street Journal denies the 97% scientific consensus on human-caused global warming

    What bothers me is the lack of common sense in the people who argue against global warming. They either hide behind kindergarden reasoning, "we had the coldest winter on record" or contrariantism for the sake of it. CO2 is created added to our atmosphere. As that happens the atomsphere gets warmer. Let's say in the old days most CO2 came from animal farts, decomp and lightening strike forest fires. Well clearly since the industrial revolution, we (humans and our by-product industries) have been contributing a lot more CO2 year after year. If you want to argue that it is to late to stop, or that we will be just fine if oceans rise, great. But why disagree with the obvious?

  18. John Oliver's viral video: the best climate debate you'll ever see

    Tom, your last point is excellent. I've just checked the robustness of the consensus figure by flipping numbers between 3rd and 4th category and they are indeed very stable and well above 90% even in most extreme cases.

    The discussion about operational definition is not so compelling to me, though. I'm not even sure where the alleged problem of exclusion comes from, but I admit the methodology of such studies is not my bag. If the goal is to get a lower bound of a consensus I don't see an inconsistency. Cook et al. found an upper bound and that was my problem, but since this figure is very inelastic, that's ok for me. Looks like I've given the guy I was discussing with too much credit. ;) Thx for clarification.

  19. 2014 SkS Weekly News Roundup #22A

    Thanks for another week of well selected articles. Here's my nomination for the next "toon of the week": http://media.boingboing.net/wp-content/uploads/2014/05/1190cbCOMIC-climate-change-deniers.jpg

    Moderator Response:

    [JH] Thaks for the positive feedback and the suggested cartoon.

  20. The Wall Street Journal denies the 97% scientific consensus on human-caused global warming

    SteveFunk:

    The Oregon Petition also includes the names of people who have passed away. There's no way to ascertain whether someone who signed the petition a decade ago and subsequently died would hold the same opinion today given the amount of scientific evidence that has accumulated over the past decade.

  21. Rapid climate changes more deadly than asteroid impacts in Earth’s past – study shows.

    mancan18 @13 - Regarding the link between continental breakup, volcanic activity and these LIP & extinction episodes:

    LIPs do seem, tentatively, to be concentrated at times when continents are breaking up. But they are caused by mantle plumes that extend from the core-mantle boundary, and not directly with the regular continental drift process.

    It's important to emphasise that these LIP monsters totally dwarf any volcanic eruption ever witnessed by humans. In recent decades the total combined annual volcanic greenhouse gas emissions, including undersea volcanics and mid-ocean ridges, are equivalent to the annual emissions of a single state like Ohio or Michigan.

    There is an association between long-term CO2 levels, climate, and the total length of subduction zones at any given point in geological time. But the climate is complex, and other factors (rock weathering rates related to mountain building, ocean currents related to continent configuration, life innovations, asteroid impacts...) all interact and play a role in global climate.

  22. Rapid climate changes more deadly than asteroid impacts in Earth’s past – study shows.

    Leland @24 from the Jourdan et al paper: "the Stage 4–5 transition is associated with a global sea-level rise and negative δ13C and positive δ34S excursions recorded in stratigraphic sections worldwide (e.g., Montañez et al., 2000; Hough et al., 2006)." [stage 4-5 is the same time as Kalkarindji.]

    Yes we see a pattern of such events. Here's a list grabbed from a couple of papers - note that the dating of some of the events is better than others. The coincidence of LIP and Mass Extinction/Climate event is strongest where the latest high-precision dating has been applied (Permian, Triassic, Mid-Cambrian).

    LIP event /extinction or climate event:

    Columba River 17ma (Mid Miocene Climate Optimum)
    Yemen/Afar 31ma (none?)
    North Atlantic 62/56ma ?PETM/Hyperthermals?
    Deccan Traps 66ma (Cretaceous extinction precursor)
    Sierra Leone 70ma (?)
    Caribbean 90ma (Cenomanian/Turonian Anoxic Event);
    Madagascar 90Ma (ditto)
    Hess Rise 100ma (?)
    SE Africa/Maud/Georgia 100ma (?)
    Kerguelen 120ma (?Aptian)
    Ontong Java 122ma (Aptian Anoxic Event);
    High Arctic LIP 130ma
    Parana-Etendeka 132ma
    Shatsky Rise 145ma
    Karoo-Ferrar-Dronning Maud Land 183ma (Toarcian OAE)
    Central Atlantic 201 (Triassic Mass Extinction)
    Angayucham 210ma (?)
    Siberian Traps 252ma (Permian Mass Extinction)
    Emeishan traps 260ma (end Guadaloupian extinction)
    Tarim 280ma (none?)
    Skagerrak- Barguzin–Vitim - Carboniferous Rainforest Collapse (Moscovian and Kasimovian stages);
    Viluy - End Tournasian;
    Pripyat–Dniepr–Donets - End Famennian–end Frasnian;
    Kola/Kontogero - End Frasnian;
    Altay–Sayan - End Silurian (?);
    Ogcheon S Korea - End Ordovician?;
    Central Asian intraplate magmatism - End Late Cambrian;
    Kalkarindji - End Early Cambrian;
    Volyn - End Ediacaran;

    (From Kravchinsky 2012 & Bryan and Ferrari 2013) ma= million years ago.

  23. Rapid climate changes more deadly than asteroid impacts in Earth’s past – study shows.

    Billthefrog @16 wow, there's a lot in there! I'll do my best...

    The Faint Young Sun Paradox is still just that - a paradox. We know from sediments at the time that there was liquid water and normal sedimentary processes, so the Earth was not frozen solid. The work of William Moore shows that very early Earth was essentially in Large Igneous Province mode all the time. There was a lot of CO2 in the atmosphere as plate tectonics handn't started yet (subduction started ~3.2 billion years ago) so the world was basically covered in volcanic islands, but lacked the large mountain ranges and surface area for weathering to draw down CO2 so fast. Yet experiments on fossil raindrops suggest the atmosphere was not so dense, so alternative atmospheric gas mixes have been inferred. We also know the oceans had about 26% more water in them, so the Earth's albedo was likely much lower.  By the time of the ice ages @2.9, & 2.5Ga, subduction had started and continents had grown, and oceans had reduced somewhat, but until oxygen arrived the atmosphere was methane-rich. There's much more than I can fit here and it is still an area of ongoing research, and there has even been a suggestion that the sun back then might have been 5% larger (effectively negating the faint young sun paradox).

    Regarding the slow decline of CO2 and temperatures since the Eocene hyperthermals,  see this post. This decline has been correlated with a reduction in subduction zone length by Prof Zeebe and others. One critical event was the marooning of Antarctica by continental drift and the establishment of the Antarctic Circumpolar Current 33.5-30 million years ago, but increased weathering (Hymalayas, Andes) had a role. I reccomend THE book on the subject: "Earth's Climate Past and Future" by Bill Ruddiman. Hope this goes some way to answering your post.

  24. The Wall Street Journal denies the 97% scientific consensus on human-caused global warming

    About 15 million people in the US have science or engineering degrees, excluding social science, according to this census source:  http://www.census.gov/prod/2012pubs/acs-18.pdf  And since the Oregon petition has been around since 1997, it surely includes a lot of people who were once skeptics but are not now, as well as fake names.

  25. Leland Palmer at 00:57 AM on 30 May 2014
    Rapid climate changes more deadly than asteroid impacts in Earth’s past – study shows.

    Many of these extinction events are associated with a Carbon Isotope Excursion (CIE)- a surge in C12 enriched carbon into the active carbon cycle. This C12 enriched (C13 depleted) surge of carbon is best explained by the dissociation of several trillion tons of methane hydrates, many scientists think.

    The carbon isotope excursions, the oceanic anoxia, and the low level runaway climate change can all be tied together into a general theory of most mass extinction events, triggered by these flood basalt erruptions and subsequent release of methane from the hydrates.

    So, now this middle Cambrian extinction joins this list, it appears. The paper is behind a pay wall, though. Does anyone know if there is a carbon isotope excursion associated with this extinction, and if so does anyone have a link to a paper claiming a coincident CIE associated with this extinction event?

    A classic paper on the End Permian mass extinction and the probable role of methane release in that extinction is here:

    How to kill (almost) all life - the end-Permian extinction event

    " The extinction
    model involves global warming by 6 degrees C and huge input
    of light carbon into the ocean-atmosphere system
    from the eruptions, but especially from gas hydrates,
    leading to an ever-worsening positive-feedback loop,
    the ‘runaway greenhouse’."

  26. Rapid climate changes more deadly than asteroid impacts in Earth’s past – study shows.

    Tom Curtis @ 15 - I concur. Thanks!

  27. Rapid climate changes more deadly than asteroid impacts in Earth’s past – study shows.

    Chriskoz @20 - That quote is direct from Jourdan et al's paper. The supplementary data can be found at ftp://rock.geosociety.org/pub/reposit/2014/2014190.pdf. see p 15 for randomness calculation.

    They admit it is a "crude estimate" but go on to say: "Nevertheless, this series of
    calculations suffice to demonstrate that the mass extinctions – LIP association cannot be due to chance with a probability of 6x10-9 % that the synchronicity between LIPs and mass extinctions is random."

  28. The Wall Street Journal denies the 97% scientific consensus on human-caused global warming

    austratsua @4:

    It's always nice to be "lectured" on how science _really_ works!


    1. Deniers deny. It's a simple, apt, descriptive adjective. And, it's far more apt than "alarmist" as the peer reviewed, scientific literature is remarkably free of alarmism. This can be contrasted to denier blogs stating "the economy will be destroyed" etc. if anything whatever besides business as normal is attempted. All the while ignoring that business as normal carries its own costs which may well "destroy" various parts of various economies, of course.

    2. Your explanation of how "science progresses by criticism" starts at the wrong place and comes to wrong conclusions. Heliocentrism did not change the course of the planets in the slightest. What heliocentrism did was allow more accurate, easier calculations. Evolution did not change how genes change over time. What evolution does is provide a nice framework for understanding these changes. There is simply NO _theory_ that is going to come along and suddenly make the Earth cool.  What could make the Earth cool is various events and processes that are not presently occurring.

    3. You don't "criticize" the fact that an apple falls when you drop it any more than you criticize the position of Mars in the sky. You criticize an explanation of why it drops or where the planet appears in celestial coordinates. And interestingly, physicists have really poor explanations--as opposed to very accurate descriptions--of exactly why that apple falls or planet moves.

    4. I suggest people taking real science courses from a real scientific sources really do understand the scientific process and the role of criticism within it.

  29. The Wall Street Journal denies the 97% scientific consensus on human-caused global warming

    Who are the 3% of climate scientists who deny AGW and what are their reasons?

  30. The Wall Street Journal denies the 97% scientific consensus on human-caused global warming

    For the latest news on the consensus amongst IPCC contributing climate scientists see:

    "Transformational Climate Science"

    Professor Peter Cox of Exeter University "provocatively" states that:

    Is it still possible to avoid 2 degrees using conventional mitigation?  In fact it's likely to be blown out of the water!

  31. Rapid climate changes more deadly than asteroid impacts in Earth’s past – study shows.

    Thanks Tom

    Thanks scaddenp

  32. The Wall Street Journal denies the 97% scientific consensus on human-caused global warming

    austratsua @4:

    "Are you seriously suggesting that the the earth's climate is as well understood as the heliocentric theory or evolution?"

    No, they were not.  They were denying that a sample of explicit endorsements as a percentage of the entire literature can quantify the level of agreement among scientists with a theory.  Such a method applied to any scientific literature would fail, which is why it is necessary to quantify all endorsements (explicit and implicity) as a percentage of all endorsements plus rejections (explicit and implicit).

    Your use of a puerile strawman to distract from the logic of the argument is noted.

    '"if the 97% expert consensus is right, it means we’re in for several more degrees of global warming if we continue on a business-as-usual path." This is false. The consensus quoted in your paper said nothing about how much the world will warm in the next century.'

    Having taken a stand for emperical science in your first determined attempt at distracting (see my prior post), you now forget that emperical study requires following the implications of a theory.  An immediate implication of a low climate sensitivity is that it is not responsible for most of the warming over the last fifty years.  The anthropogenic forcings are fairly well known, and coupled with a climate sensitivity would not have produced enough warming to account for 50% or more of the recent warming.

    Conversely, with moderate or high climate sensitivities, the projectible changes in forcings with BAU will result in a large temperature response in the 21st century.

    That you think otherwise merely shows that you do not follow through to the emperical implications of the theories that you support, or in this case reject. 

  33. The Wall Street Journal denies the 97% scientific consensus on human-caused global warming

    I could ask, if coal is cheap, then why do US coal producers need subsidies and protection?

  34. The Wall Street Journal denies the 97% scientific consensus on human-caused global warming

    austratsua @4:

    "Firsly, it is unseemly to attack people who disagree with you with terms like "denier"."

    Firstly, despite your complaint, nobody was called a "denier" in either the original post, nor in the three comments that preceded yours.  Rather, it was said that certain people deny certain propositions, ie, they claim that those propositions are false.  You are so determined to control the terms of the debate that even use of simple verbs to describe the beliefs of others is now not OK with you.

    So, here are two simple questions:

    1)  Do Bast and Spencer claim that there is not a 97% consensus of climate scientists who agree that >50% of recent global warming was caused by anthropogenic factors?

    2)  If Bast and Spencer do make that claim, why do you react so strongly against the simple description that they deny that claim?

    Secondly, despite you concern about how unseemly the missing attack was, you seem unconcerned that Spenser should refer to climate scientists as "Global Warming Nazi's", unconcerned about Bast's use of billboards to draw a connection between AGW and the Unabomber, unconcerned about the frequent accusations that climate scientists are guilty of fraud (scientific, and less frequently) financial, an unconcerned about accusations that people seeking policy action against AGW are routinely accused of desiring genocide by your fellow pseudo-skeptics.  Absent evidence the contrary, in the form of links to comments where you have protested such activity by your fellow pseudo-skeptics, I will conclude that your concern for civility is, like that of most of your fellow travellors, one sided and hypocritical.

    The simple fact is that concern about the term "AGW denier" does not arise from genuine feelings of offense.  They arise from the same desire to win the debate by persuasive definitions that led pseudo-skeptics to call themselves "skeptics".  It is an attempt to controll the debate by controlling the language used in the debate.   As with Orwell's "Big Brother", it shows a determination to controll the language to limit what can be thought.

  35. Rapid climate changes more deadly than asteroid impacts in Earth’s past – study shows.

    Thanks Howard for another innteresting article about extinction.

    I want to understand this sentence:

    The authors note that the correlation between LIPs and severe extinctions is now so strong that there is a “negligible 6×10–9% probability that such correlation is due to chance alone,”

    (my emphasis)

    I'm not sure, if you refer to http://dx.doi.org/10.1016/j.palaeo.2012.06.029 as the source of that sentence because I don't have free access to it. So I want to confirm with you wheather this number is or is not a typo. How can we be so sure about the causes of events so deep in the paleo (60-500Ma)? What do you mean exactly by "due to chance alone" and how do you exclude an event so defined with such inbelievably high certainty?

  36. Doug Bostrom at 18:45 PM on 29 May 2014
    The Wall Street Journal denies the 97% scientific consensus on human-caused global warming

    "cheap coal that could allow them access to clean water and clean air"

    That's rather hysterically funny. 

    Here's what cheap, clean coal looks like in situ where "they" enjoy it : 

    With regard to risk aversion, we're all in this car together and (to stretch the metaphor) there are no seatbelts. I for one would rather have a cautious driver at the wheel, "inflicting" risk aversion on me, rather than a reckless fool doing the driving. 

    Doubtless folks wringing their hands about poverty in the 3rd World have already exhausted their own personal means of correcting that problem, for surely they would not be using such an emotional appeal as a cheap rhetorical expediency. 

  37. The Wall Street Journal denies the 97% scientific consensus on human-caused global warming

    "Should wealthy risk-averse westerners be allowed to force poverty-stricken Indians and Chinese not to have access to cheap coal that could allow them access to clean water and clean air and a good life?"

    Show me where this has been suggested. You could try discussing things seriously instead of jumping into cheap rhetoric. Or do actually believe this from reading misinformation somewhere? In fact the usual suggestion is to let non-Western countries increase FF use while alternatives are slowly brought in while the affluent West very sharply reduce their emissions. That would have been substance of all recent climate conferences.

    It would be reasonable to hold alternative opinions to AGW if there was actually some data to support some other idea as opposed to, yes, denialism, and misinformation campaigns. If you really think that this exists by all means present the evidence on an appropriate thread.

  38. Rapid climate changes more deadly than asteroid impacts in Earth’s past – study shows.

    @Tom & Glenn          - Thank you

    @ Graham                 RE: the RCP guide- Wow

  39. The Wall Street Journal denies the 97% scientific consensus on human-caused global warming

    "Based on this quote the author is so sure that anthropogenic global warming is true that he thinks it's as obvious as the fact that the earth goes around the sun."

    That CO2 is a Greenhouse Gas and warms the planet is as certain as the earth's goes round the sun. And this physical truth of global warming has gone through the progression from hypothesis, to theory, to accepted common knowledge, with all the trials and tribulations of peer review with several counter theories and arguments put against it over some 150years or so.

    That this warming is amplified by the earth's internal systems (the climate sensitivity) has also gone through the same rigorous progression.

    The uncertainty is how much the earth's internal system amplify the warming and consensus on an exact figure for this is hard to find, for 2 reasons, there are uncertainties in the measurements (like all measurements) and the system is complex and behaves chaotically, meaning that the climate sensitivity is dependent on the initial conditions of the system, in this the earth's continental arrangement, amount of sea ice present, amount of oceanic ice, amount of O2 etc, over geological time and thus is a moving target overall. Being in a time when there is large oceanic ice cover to melt away quickly is suggestive that this might be a time of higher CS than at others. As climate being dangerous, well as in the previous article this week, when CO2 and SO2 are released in large amounts into the atmosphere life can be dramatically reduced it appears, and although that is open to question, as the evidence mounts it is well into the established theory realm and thus most scientist would agree that global warming induced by burning coal can be quite dangerous I would suspect.

    Maybe the authors should put out an scientist e-mail and ask several thousand that question sure they find that most would feel that climate change can be very dangerous to life per se never mind a complex civilization with ~50% of its population and more of its wealth near the ocean edge when sea levels are set to rise.

     

     

  40. The Wall Street Journal denies the 97% scientific consensus on human-caused global warming

    Wow, where to begin. Firsly, it is unseemly to attack people who disagree with you with terms like "denier". Criticism is central to scientific progress. You never know, you might actually improve your methodology if you listen rationally to criticism. Calling them "denier" and talking about irrelevent facts about their history and rupert murdoch is at best "post-modern" and at worst a cynical attempt to evade the criticism.

    "By that standard, there’s less than a 1% expert consensus on evolution, germ theory, and heliocentric theory, because there are hardly any papers in those scientific fields that bother to say something so obvious as, for example, “the Earth revolves around the sun.” The same is true of human-caused global warming." 

    Are you seriously suggesting that the the earth's climate is as well understood as the heliocentric theory or evolution? Have you heard of scientific fallabalism? It goes like this. A new theory is always assumed to be wrong. This is the default position. Based on this quote the author is so sure that anthropogenic global warming is true that he thinks it's as obvious as the fact that the earth goes around the sun. If all scientists thought this way they would never be able to correct their mistakes and they would hold on to theories no matter what data comes in.


    "if the 97% expert consensus is right, it means we’re in for several more degrees of global warming if we continue on a business-as-usual path." This is false. The consensus quoted in your paper said nothing about how much the world will warm in the next century. In fact the criteria did not require any quantification of the amount of warming in the future or in deed in the past 150 years. Accordingly, one could rightly claim to belong to your consensus and still predict relatively little warming over the next century. And then there is the issue of dangerousness. You are right to say that some people are more risk-averse than others. But does this mean that highly risk-averse people should be able to force those who are not so risk averse to pay more for energy? Should wealthy risk-averse westerners be allowed to force poverty-stricken Indians and Chinese not to have access to cheap coal that could allow them access to clean water and clean air and a good life? 

  41. It's too hard

    davidnewell at 13:13 PM on 29 May, 2014
    As more and more evidence accumulates in regard to the looming catastrophe, more serious consideration may be given to ways to counter at least the rate of increase, so that more time is available to employ other methods, and educate "the masses".

    Somewhere here someone took some "shots" at the technique found at

    WWW.EarthThrive.Net,

    mumbling a dismissive comment relating to the amount of CO2 dissolved in the Gulf Stream, or something.. Totally non-bearing on the proposal.

    ===============

    I propose to defend the matter, thru simplicity.l. Many here may find "fault",

    but it's hard to argue against this..

    =========================

    I propose a "new measurement" of alkalinity.
    Maybe it's NOT new, but it's new to me, and facile for raising my point.

    Total Alkalinity, volume, (vs. CO2) = volume of pure CO2 adsorbed / volume of solid substrate

    Abbreviated TA(sub)v or TAv, it can be in any dimensional system,
    as long as they are "in common". ( of course)

    My laboratory measurements were in CC.

    Ranges of TAv for surface alkali soils ranged between about 2 1/2 to over 3.

    (there are speculative reasons to think that lower levels will be more reactive..)

    I presently cannot find this (following) calculation, so anyone of interest can do so.

    Given the elongated inverted pyramid approximation of (say) the Black Lake Desert,

    which is about 25 miles long by 10 miles wide..

    Assume that it is a rectangular box 1 mile deep.

    Given a conservative TAv of 2.5, what is the weight of CO2 in tonnes possible if all the material was reacted.???????

    After that is derived, then we can see if further consideration of the other objections may be warranted.

    ==============

    Lets see: 22.4 liters^ of CO2 = 1 mole wt of CO2, in grams, at STP.

    formula wt = 44.grams/ mole

    ======================

    According to my trusty HP-55, which is still running after all these years,

    under consideration is 25X10X1, which is 250 cu miles of "dirt",

    which can ultimately sequester (with a TAv of 2.5), 625 cu miles of CO2.

    1 cubic mile =4.16818183 × 10^15 cubic centimeters
    625 " = 2.605113641 x 10 ^18 "
    or 2.605113641 x 10 ^15 liters.

    or (changing decimal pt) 26.05113641 x 10 ^17 liters,
    which, when divided by 22.4 liters, = 1.2 X 10^17 moles of CO2,
    or, multiplying by the mole weight of CO2, 44,
    equals ~5 X 10 ^ 18 grams ,
    or 5 X 10^12 tonnes.

    Anyone who used an HP55 in college is old as the hills,
    OVER the hill,
    and probably missing a screw, as well..

    Please point out my errors, other than those which are simple approximations.

    =======================

    All that is needed, urgently, is to employ a technique
    which reduces the rate of increase in circulating CO2,
    while "other measures" take effect. If we can take 5 billion tonnes
    OUT of the air, per year, we "MIGHT" have a chance.

    Pumping costs be damned!
    AT the very LEAST civilization is "under threat" by our combined ignorance.
    (This "rant" is more "refined" at www.EarthThrive.net, so I'l discontinue it,
    here..)

    For far less than Gov Moonbeam's favorite projects of continuing stupidity,
    ie the "twin tunnels" under the Delta, and/or the "Train to Nowhere",
    we could implement this plan,
    AND
    (side issue)
    produce a hell of a lot of clouds going dowwind.

    It may be noted that many of the playas (the above is just an example, although one of the larger playas, to be sure..) are "saline" in nature, and are "wet" at some depth under the surface. Maintaining conditions for bicarbonate stability (dampness) is not difficult.
    Thank you for your time.

    David Newell

    =================

  42. The Wall Street Journal denies the 97% scientific consensus on human-caused global warming

    Moderation

    Moderator Response:

    OnePlanetForever, please take note and abide by the comments policy, noting especially the section on politics. There are plenty of other sites for political rants. Please stick to the science.

  43. Glenn Tamblyn at 10:56 AM on 29 May 2014
    Rapid climate changes more deadly than asteroid impacts in Earth’s past – study shows.

    Billthefrog

    Another important event around 30-35 million years ago was the separation of Sth America and Antarctica, allowing the formation of the Antarctic circum-polar current, tending to isolate Antarctica and allowing it to colmore

  44. Rapid climate changes more deadly than asteroid impacts in Earth’s past – study shows.

    mancan18 - you might also like to have quick look at this guide to the RCPs. Economics would prevent burning everything but working out atmospheric concentrations also require taking into account how the natural systems draw-down (or otherwise) excess CO2. A typical pseudo-skeptic will argue that environment will continue to draw down 50% of emissions, ignoring that as temperatures rise, the oceans eventually emit CO2, rather than absorb it.

    You can play with really extreme scenarios but the RCPs are a far better guide to what is realistic (and frightning enough at that).

  45. Rapid climate changes more deadly than asteroid impacts in Earth’s past – study shows.

    Thanks Howard,

    What you say pretty well reinforces what I understood from the Climate Change MOOC I recently did at Exeter University.

    The reason I put a question mark on the Palaeoproterozoic snowball/slushball event having primacy was simply cause I don't know enough about the earlier Archean Eon. Could the Faint Young Sun of those far off days have been instrumental in an even earlier snow/slush ball? Do we have enough preserved crust from that long ago to tell? I know that some zircon crystals have been radio-dated at around ~4.3 billion years, but whether there is sufficient preserved crustal material - I just don't know.

    Moving to more recent times and the Pleistocene glaciation. If my understanding is correct (cue a huge guffaw from the wife at this point), temperature wise we've been on a downward slope since the heady days of the Eocene. The Indian Plate went sailing full tilt into the Eurasian Plate starting about 65 MYA and causing (initially) a major carbon release into the atmosphere. (Chicxulub, the Deccan Traps and the start of the Himalayan orogeny - a lot of stuff going on about then.)

    About 50 MYA, the Himalayas and the Tibetan Plateau had popped up, exposing lots of nice fresh silicate surfaces just ripe for weathering - with the concommitant CO2 drawdown. (I don't really know how much credence is given to the postulated Azolla Event and its resulting major carbon sequestration which is, by some, thought to have happened at about the same time - to within a million years or so.)

    Obviously, the continents were still dancing around, getting their rocks off, so to speak. (Stealing a line from the great Terry Pratchet.) However, I understood that it was the sealing off of the Panama Ithmus that was the final piece of the jigsaw that allowed the reformation of massive polar ice sheets.

    Have I got that just about right?

  46. Rapid climate changes more deadly than asteroid impacts in Earth’s past – study shows.

    billthefrog @6, while rate of change is the main driver of extinction, the Earth can, and has in the past, reached temperatures where the absolute temperature value drives extinction.  The obvious examples are the two slushball Earth episodes discussed by howardlee @12.  Equivalent episodes today would extinguish all, or nearly all complex multicellular life on Earth, regardless of the rate of onset.

    Of more concern are episodes like the end Permian mass extinction where tropical temperatures rose sufficiently to be seasonally uninhabitable.  Global temperatures of about 10 C above the preindustrial will make large sections of the tropics uninhabitable to large warm blooded vertebrates based on absolute values of wet bulb temperature.  There is evidence that the absolute limits are to be found for most complex multicellular life at temperatures about that level.

    Humans would have to be terminally foolish to raise temperatures so much that absolute limits on temperature become a major factor in extinctions.  Currently, however, terminally foolish best describes global policies on geen house gases.

  47. Rapid climate changes more deadly than asteroid impacts in Earth’s past – study shows.

    mancan @18, a worst case emissions scenario would not just consume proven reserves (on which your figure is based) but a substantial proportion of the total resource base (TRB).  That is, it will access coal not currently commercially viable either due to increased energy prices, or due to improved technology (such as coal seam gassification).  Unsurprisingly, estimates of the TRB are less certain than those for proven reserves.  At the outside, determined exploitation of the fossil fuel TRB would lift atmospheric CO2 levels above 5000 ppmv (based on the IEA 2011 estimate).  At the low end, determined exploitation of the TRB will lift atmospheric CO2 levels to about 1500 ppmv (based on WEC 2010 figures).  The former will raise temperatures to levels at which multicellular life may be impossible - and certainly impossible for large, warm blooded vertebrates such as humans.  The later will lift temperatures to levels at which periodic tropical heat waves will result in 100% mortality for large, warm blooded vertebrates.  That may be devestating, even apocolyptic for the economy, but should not represent an extinction threat for humans (many of whom live outside the tropics).  Intermediate estimates will reproduce conditions very similar to those during the end Permian extinction, making the tropics seasonally uninhabitable for large, warm-blooded invertebrates.

    For practical purposes, I do not think these scenarios are relevant in that they would require sustained, high tech exploitation of fossil fuel resources well into the next century - something that may be made economically impossible by global warming, and certainly socially impossible.  I think the upper end of realistic scenarios is well represented by the IPCC's RCP 8.5 scenario out to 2100:

    Beyond 2100, we will need to reduce CO2 emissons to zero to avoid the very dangerous tail of the RCP 8.5 scenario.

  48. John Oliver's viral video: the best climate debate you'll ever see

    BojanD @8, if you are rating abstracts, your task is to assign each abstract to one of seven bins (categories).  In doing so, each abstract can only be assigned to one bin; and no assignment can be arbitrary.  These two requirements, together with the guidelines on rating abstracts and the descriptions of the rating levels themselves provide an operational definition of "endorses AGW" and "rejects AGW" for Cook et al.

    Now, suppose you have an abstract that says in part "40 to 45% of the recent (late 20th century) temperature rise is attributable to anthropogenic factors, with natural factors being responsible for 55-60% of that rise".  If we compare the abstract to rating category 7 (rejects with quantification), then we must place this abstract in that bin for it explicitly states, and quantifies, that natural factors are responsible for more than 50% of recent warming.

    According to you, however, we must also place the abstract in bin 2 (explicitly endorses without quantification), for (according to you) "endorsing AGW" means anthropogenic factors are "means [are] a cause and not necessarily the main one", and if they are are the cause of 40-45%  of the recent warming, they are certainly a cause but not the main one.

    That means by your definition, either we must place that abstract in two bins, or the bin we place it in is arbitrary, depending on which bin we compare it to first rather than any particular features of the abstract.  As placing an abstract in two bins is prohibitted, and as rating must be non-arbitrary, it follows that your definition is wrong.  Indeed, the only definition that does not fall foul of the requirement of exclusiveness of rating (only one rating permitted) and non-arbitrariness is a definition that defines "endorses AGW" as endorsing recent warming to be at least 50% caused by anthropogenic factors. 

    In one respect, this more precise definition does not make much difference in that we gain the greater precission of definition only at the cost of a potentially greater error rate in classification.  That is, with the more precise definition, it is more probable that an abstract that should have been rated 4 was rated 3.  However, even if we suppose 50% of all endorsing abstract ratings reported in the paper are in error, and should have been rated 4, that still leave a 96.2% endorsement rate among papers not rated as neutral (compared to 98% reported in Cook et al).  Such a 50% error rate is absurdly high, so whatever the actual error rate, the substantial result of Cook et al stands even with the accurate, precise defenition of "endorses AGW".

  49. Rapid climate changes more deadly than asteroid impacts in Earth’s past – study shows.

    I like following the Skeptical Science discussions but I'm only a lay person with regard to climate science. I was wondering whether there were any studies that related continental drift and the break up of the supercontinents and shifting of the continental plates around the planet to the excessive volcanic activity that led to these mass extinctions.

    I know that the IPCC do have a climate prediction outcome for business as usual, but has anyone done a maximum emissions outcome if all the known reserves of fossil fuels are consumed. Also, it seems to me that the only analyses regarding emissions is based on current consumption, where great comfort is taken by deniers that there will be 100 to 200 years of coal left to burn. But, this assumes that the developing nations will remain low emitters per capita. What would happen if everyone in the world were emitting per capita the same as the high emitter per capita countries like Australia or the US? Unlike the CO2 doubling debate, perhaps there also needs to be a worst case maximum emission scenario debate, because this would get to the heart of the equity debate. My simplistic analysis of such a scenario indicates that there would only be about 40/50 years of coal left if we consumed at a maximum emissions rate and we would put the CO2 levels back to the time of the dinosaurs in a very short time. I wonder what the predictions regarding the climate and mass extinctions would be in such a scenario.

  50. Rapid climate changes more deadly than asteroid impacts in Earth’s past – study shows.

    Joel and Bill - There have actually been 2 "snowball" episodes, and a number of major ice ages on the planet, long before the most recent Pleistocene ice age.

    About 2.9 billion years ago there was an ice age when microbes evolved methanogenesis, which reduced the CO2 levels in the atmosphere. This was early in Earth's life a time when the sun was less bright than now.

    The first snowball Earth (actually more of a slushball because some areas were not frozen) coincided with the rise of atmospheric oxygen around 2.5 billion years ago. The Earth froze because there had been a lot of methane in the atmosphere, which oxidized on contact with the newly-minted oxygen, removing a greenhouse gas blanket and plunging the planet into a deep freeze in 3 separate ice ages spread over 200 million years.

    The second snowball Earth (the famous one - but even this was more of a slushball) occurred  around 700 million years ago. This was in response to the first greening of land surfaces, which boosted oxygen levels that had been declining since the Great Oxidation Event 2.5 billion years ago. Boosting oxygen once again removed methane that had recovered somewhat as oxygen declined, but more importantly it boosted rock weathering rates which drew down CO2 from the atmosphere. The episode involved at least 3 separate global ice ages, 720-700 million years ago, 650-630 million years ago, and briefly 580 million years ago.

    There was another brief ice age around 517 million years ago known as the MICE event in response to the Cambrian Explosion proliferation of life (and probably enhanced biological pump). 

    There was another major ice age in the Ordovician in response to the rise of vascular plants and the enhanced weathering and carbon drawdown they triggered.

    The ice ages in the Carboniferous-Permian were probably a combination of so much carbon being locked away as coal (CO2 levels down to about 220ppm) and the coincidence of high continental areas at the South Pole. There's some suggestion that an asteroid impact may have tipped the balance to ice age at one point also.

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