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Comments 60351 to 60400:

  1. Shakun et al. Clarify the CO2-Temperature Lag
    william, A suggestion... use scholar.google.com to search for papers on the subject, and look at them. They aren't as hard to read as you might think, and are far more valuable than a blog by someone who is sort of thinking about things. That said, this has been discussed at length in the literature, and a great debate is raging because nothing ever seems to adequately answer the question that balances all of the ledgers in both quantity and timing. Specifically, I've seen references to methane release from peat bogs, huge fires in peat bogs (turning the methane and other carbon directly into CO2), and numerous other ideas thrown around. BTW, while copies of papers are usually behind paywalls, I've very often found downloadable PDFs (often by including type:pdf as a search term in a regular google search, although it doesn't work on scholar.google.com).
  2. Shakun et al. Clarify the CO2-Temperature Lag
    The production of CO2 from warming oceans, or at least a reduced absorbtion of same sounds feasible as a feedback mechanism to explain the accelerated melting of continental ice sheets. I wonder, though, if there wasn't another feed back. When you consider the depth of the ice sheets and hence the pressure at the bottom, all seeps of methane, and for that matter, Carbon dioxide, from shale, coal and hydrocarbon deposits plus organic decay would have collected as clatrates at the bottom of the ice sheet. These would have been released at each Milankovitch nudge. If the output of these gasses was sufficient a run away melting could have occurred http://mtkass.blogspot.co.nz/2011/09/continental-glacier-meltdown.html
  3. CO2 measurements are suspect
    danielc's comment of 6:14 AM, April 11th, 2012:
    "@wsugaimd: Go here: Movie showing CO2 levels measured over the last 50 years it includes information from ice cores, and there are MANY data points, not just at hawaii. Go here: impact of eruptions on global CO2 levels - essentially unmeasurable. and go here: satellite measurements of CO2 compared to Mauna Loa Being skeptical of measurements taken at one point, using one method is reasonable, but CO2 measurements have been made at many, many points using many, many methods...
    Jim Eager's comment of 6:21 AM, April 11th 2012:
    Wsugaimd @38, your skepticism seems highly selective, since Mauna Loa is not the only location where atmospheric CO2 is monitored. Similarly, ocean pH is monitored at many locations around the globe. If you are truly skeptical then you should be noting what those locations also show, not just those in Hawaii. As for comparing human CO2 emissions to total CO2 content of the atmosphere, your 1% figure suggests that you are no skeptic, but rather that you are using the trace gas argument distraction (see the "Argument" button in the top bar). Consider that every single natural source of CO2 is offset by a natural absorption of CO2. The ocean continuously exchanges CO2 with the atmosphere, making it both a source and a sink for CO2. However, it is currently a net sink, meaning it absorbs more CO2 than it emits, which is why ocean pH is decreasing. Similarly, the terrestrial biosphere both emits and absorbs CO2, and it, too is currently a net absorber, although that may well change. Even volcanic emissions of CO2 are offset by geologic sequestration of CO2 via silicate rock weathering and calcium carbonate shell deposition on the sea floor. However, there is no human absorption of CO2. Zero. There is only human emission of CO2. Every gram of CO2 we emit must either be absorbed by a natural sink or remain in the atmosphere. Fortunately the ocean, biosphere and lithosphere absorb 100% of natural emissions, *plus* roughly half of the carbon that humans emit, leaving only half of it to accumulate in the atmosphere. In other words, we humans have been responsible for 200% of the measured 38% increase in atmospheric CO2. A true skeptic should be able to tell the difference between a 1% annual emission rate and a 38% cumulative increase, don't you think?"
    danielc's comment of 6:33 AM, April 11th 2012:
    "@Jim Eager #42: The argument I like to use is this: Say you have 10,000 dollars in the bank (that's 1 million pennies). 300 of those pennies are red pennies, and they earn triple interest. Every day, I am going to add three red pennies to your bank account. For every time you earn triple interest, another free red penny is added to your bank account (positive feedback). Are you going to refuse? NO! Are the red pennies in your account, and the extra red pennies I add year on year (and the triple compound interest they receive going to add significant amounts of money to your account? YES! Esp. over significant amounts of time."
    Moderator Response: TC: The three quoted comments above are in response to wsugaimd's of topic comment here, and have been quoted here in lieu of simple deletion.
  4. DeConto et al: Thawing permafrost drove the PETM extreme heat event
    @Sphaerica: I just went to a talk given regarding this issue... there are folks trying to use high-frequency lake bed deposits as proxies to "tune" the orbital predictions... in the Triassic!! Woot!
  5. Monckton Misleads California Lawmakers - Now It's Personal (Part 2)
    Dana on Monckton and attribution, yes I have already nailed some of those but will be out of action for about 24hrs now before I can post my completed my response over at Concordensis.
  6. DeConto et al: Thawing permafrost drove the PETM extreme heat event
    Karamanski, To clarify Daniel's comment, should it not be clear to you (and it wouldn't be, if you don't understand the reference to the 3-body problem)... the issue is not that the Milankovitch cycles don't apply or or that they do apply but their power "fades" further back in time. It instead refers to the fact that prediction the motions of more than 2 bodies whose mass, velocity and position all influence each other, becomes quite complex. Figuring out exactly where all of the planets were that far back, and how they all influenced each other, gets harder and harder the further back you go, while every bit of error or uncertainty introduced makes it even harder to go further back than that. Hence... it's really hard to understand that aspect of the problem.
  7. DeConto et al: Thawing permafrost drove the PETM extreme heat event
    addendum: The authors use Laskar, 2004 to get a "best look" at the orbital forcings, but keep in mind that those forcings are quite noisy, and there is a lot of chance for significant error... the other data they use to constrain global temperatures certainly help... but there are a lot of unconstrained variables in play.
  8. DeConto et al: Thawing permafrost drove the PETM extreme heat event
    @SPhaerica the other issue with milankovitch cycles is that the orbital predictions start to break down the further back in the past you get - classic three body problem issue... http://www.astro.gla.ac.uk/honours/labs/solar_system/papers/laskar.pdf There are problems with using milankovitch orbital forcing models on rocks that are that old... those problems are somewhat surmountable if the system can be "tuned" with verifiable independent data sets....
  9. DeConto et al: Thawing permafrost drove the PETM extreme heat event
    2, Karamanski, The answer to your question is in the post above, but perhaps it's not clear due to the way it's described. The climate of any age depends very, very much on many factors, including ocean currents and the configuration of the continents. As such, simulations are necessary to try to determine exactly which orbital configurations might have resulted in the observed events, and why. At the same time, the theory of Milankovitch cycles itself is fairly new, and by itself only explains the trigger for glacial/inter-glacial transitions, but not by itself the entirety of those transitions. So... Milankovitch cycles are "orbital variations," or rather occasional configurations of various orbital factors that combine to create certain conditions. Similarly, De Conto et al were attempting to achieve that same understanding of how orbital factors might have influenced the Paleogene. So your answer is... similar in nature, and some day they might even call them "the Paleogene Milankovitch variations," but calling them Milankovitch cycles and then expecting to see the same variations is overly simplistic.
  10. Shakun et al. Clarify the CO2-Temperature Lag
    @Jim Eager #42: (snip)
    Moderator Response: TC: Of topic comment snipped and moved to the appropriate thread. Further of topic comments will simply be deleted.
  11. DeConto et al: Thawing permafrost drove the PETM extreme heat event
    Are the orbital variations that instigate the hyperthermals the same as the Milankovitch cycles that drive the glacial-interglacial oscillations? The 1.8-1.2 million year periodicity of the suspected orbital cyles seems inconsistent with the 100,000yr, 41,000yr, and 21,000yr periodicities of the Milankhovitch cycles. Could someone please explain this?
  12. Shakun et al. Clarify the CO2-Temperature Lag
    Wsugaimd @38, (snip)
    Moderator Response: TC: Of topic comment snipped and moved to the appropriate thread. Further of topic comments will simply be deleted.
  13. Shakun et al. Clarify the CO2-Temperature Lag
    To keep the thread on topic, if people would not further respond to wsugaimd, that would be appreciated. The references to pertinent threads are appreciated, but let it go from here.
  14. Shakun et al. Clarify the CO2-Temperature Lag
    @wsugaimd: (snip)
    Moderator Response: TC: Your off topic comment has been moved to a more appropriate thread as suggested by DSL @39. At SkS we try to keep discussions on topic both in order to keep them focused, and in order to make it easier for our readers to find the appropriate discussion. Your comment was, IMO, particularly informative and I hope wsugaimd lives up to his claim of skepticism by following the link and reading your comment, not to mention the relevant article. Further of topic comments will simply be deleted.
  15. CO2 measurements are suspect
    wsugaimd, how do you explain the Keeling Curve? The steady rise of atmospheric CO2 cannot be explained by a nearby volcano. Also, the Hawaiian measurements are corroborated by independent measurements. Read the article above.
  16. Shakun et al. Clarify the CO2-Temperature Lag
    wsugaimd, if you are truly skeptical, then you will respond to the response you're about to get. First of all, let me point you to the appropriate threads for each of your arguments. Responses to your comment should be placed on the appropriate threads: CO2 measurements are suspect OA Not OK
  17. 2012 SkS Weekly Digest #14
    Charlie A: For the record, I accorded a "Hat Tip" to Joe Romm for this particular cartoon because he had posted it first. My H/T does not have anythiong to do with the Romm article that you have found fault with. If you want to critque Romm's article, you can do so directly on his website.
  18. 2012 SkS Weekly Digest #14
    Charlie A: "Toons of the Week" are chosen for their ability to make people laugh and/or cry as the case may be. They should not be, an indeed cannot be, equated to a an article based upon peer-reviewed science. You have made your point about this particlur cartoon so let's move on.
  19. Shakun et al. Clarify the CO2-Temperature Lag
    I have to be honest here. I am a skeptic. And heres why. I live on the slopes of Mauna Loa, not too far away, is the Mauna Loa Observatory (MLO) where the famous Keeling Curve was made. Its located at the 9000ft elevation(I've been there several times) and just below it, at the 4000 ft level is the most active volcano, Kilauea and its sister, Pu'u O'o vent which has been continuously erupting since 1983. Atmospheric inversions can bring up the C02 to the MLO and causes astronomical spikes in C02. Oceanic acidification data has come from the University of Hawaii Aloha research station located 100km N of Oahu...just at the edge of the great plastic debris field, which is being enhanced by 25 million tons of debris from the Japan earthquake. The biological activity in this area is logarithmically increased due to available surface area of this debris. And with the increased metabolism, there is significant release C02 and organic acids which decreases the pH. Also, the amount of sulfuric/sulfurous and hydrochloric acid from the volcano emissions blows over this area(estimated between 2000-10,000tons/day). With Kona winds, the vog plume blows over the Aloha Station, and currents regularly carry this acidified water to this area. Man also produces 27 billion tons of C02/yr but this is released into an atmosphere that already has 3,600 billion tons. Do the math and man puts out three fourths of 1% of all C02. Seems quite small.... These and other questions have always made me "skeptical".
    Moderator Response:

    [DB] The topic of this thread is "Shakun et al. Clarify the CO2-Temperature Lag". In the spirit of true skepticism, we do expect for you to follow up with any further questions on the more relevant threads already supplied to you by the helpful participants here. And when one "does the math" 30 gigatons of annual emissions heretofore sequestered from the carbon cycle that man is now injecting as a bolus slug back into that cycle quite scarcely "seems small".

    [Sph] wsugaimd, Please continue to be skeptical! Pursue your questions to the end. Please engage all of your questions on the appropriate threads, because they truly are very simple questions to answer, and they can be answered unequivocally, beyond all doubt. The points you raise have solid, indisputable answers.

    As such, if you pursue your skepticism, and then go beyond that to ask further questions and to properly understand the answers, you will begin to understand the problem we all face.

  20. Shakun et al. Clarify the CO2-Temperature Lag
    @Jim: absolutely correct... hence, the dry valleys in antarctica... colder = dryer, and dryer = less snow. I agree that it is a less important effect, but the cumulative impact of both hotter summers (increased melting) and colder/dryer winters (decreased accumulation) act effectively together to remove snow/ice rather rapidly. The current situation is "special" due to the fact that we are getting BOTH hotter summers and warmer winters - more melting AND more snow in winter... strange combination due to the overall net increase of CO2 (heat trapping)...
  21. Monckton Misleads California Lawmakers - Now It's Personal (Part 2)
    Lionel @20 - the reason Monckton's attribution is vague is undoubtedly because as usual he's misrepresenting his sources. Last time he claimed near unanimity regarding the cost effectiveness of his do-nothing path his reference was a paper by Tol. I looked at that paper, and it actually says the opposite - that a carbon tax is the proper response. Mockton thus far has been unable to point to a single peer-reviewed economics paper that supports his do-nothing approach, let alone a 'near unanimity'. As usual, he's full of crap.
  22. Shakun et al. Clarify the CO2-Temperature Lag
    Re Daniel @ 35, while the corresponding decrease in high latitude winter insolation and consequent more extreme winter cold is less important, even this acts to inhibit ice sheet growth as reduced moisture leads to decreased snowfall accumulation and thus reduced ice formation. It's a two-prong attack on the ice sheet: less new ice formed during the colder, dryer winter, more old ice melted in the warmer, wetter summer.
  23. Monckton Misleads California Lawmakers - Now It's Personal (Part 2)
    John Russell @19 I posted a comment over at the foot of that second Concordensis article and Monckton of Brenchley has Gish Galloped in including this odd statement:
    'The economic argument against acting on CO2 is even stronger than the political argument. Even if one were to suppose, per impossibile, that the 3 Celsius degrees of warming predicted by the IPCC for this century as a result of our emissions of greenhouse gases were actually likely to occur, only 1.5 Celsius of this warming is attributable to the CO2 we add to the atmosphere this century...'
    and
    'the peer-reviewed literature of climate economics is near-unanimous in concluding that it is more cost-effective to do nothing now and to pay the cost of focused adaptation to any adverse consequences of global warming that may in future occur than it is to spend any money now on climate mitigation.'
    I was trying to discover how he can come to these conclusions but have been hamstrung by poor internet connectivity and sickness. I nearly have a response to some of that gallop but his attribution is always rather vague.
  24. 2012 SkS Weekly Digest #14
    Charlie A: I'm sure you've been constantly pushing that same stark choice over at websites such as WattsUpWithTthat and Bishop Hill when they engage in the same, right? Right? In any event, why you can't be bothered, in your criticism of this cartoon, to acknowledge the multitudes of other articles here on SkepticalScience which thoroughly discuss the scientific literature? I trust the false dichotomy you present is just an error. Right?
  25. Shakun et al. Clarify the CO2-Temperature Lag
    @Tom Curtis: I stated "Increased Northern and Southern Hemisphere summer insolation" - meaning more heat in Northern summer (June/July) and more heat in Southern summer (Dec/Jan). Your statement is more properly worded than mine, but they mean the same thing. Also, yes there was a decrease in insolation in the same places in their respective winter seasons... but the important thing is the summer, because a change from very cold to extremely cold is not as important or as impactful as a change from cool to hot....
  26. 2012 SkS Weekly Digest #14
    Alces, Please reference my napkin calculations here, where I conclude that:
    we would need to plant, today, redwood forests on at least 75% of all arable/agricultural land, and to allow them to grow for 100 years, before they successfully drew enough carbon (337 Gt) from the system to lower atmospheric CO2 levels back to the pre-industrial age... ...with only 25% of the agricultural land available after starting the "great carbon absorption" forests, we'll only be able to feed 25% of the 7 billion people currently alive.
  27. Shakun et al. Clarify the CO2-Temperature Lag
    danielc @32, with regard to your (1),the orbital change causes increased NH summer insolation and SH winter insolation. It also caused decreased NH winter insolation and SH summer insolation, as can be seen here: Caption reads:
    "Fig. 1. Comparison of insolation anomalies (16) over the past 150,000 years for 70'N (top), 50'N (middle), and 80°S (bottom). Insolation sufficient to begin major melting leading to the last interglaciation occurred only after ca. 135,000 years ago (line labeled ‘A’); an inference based on the observation that major melting over the more wel-constrained and re-cent deglaciation did not begin until the same level of insolation was reached at ca. 15,000 years ago (30) (line labeled ‘‘C’’). A much higher rate of Northern Hemisphere summertime insolation increase existed over the penultimate deglaciation (line labeled ‘‘B,’’ ca. 130,000 years ago) than over the most recent deglaciation (line labeled ‘D,’ ca. 12,000 years ago)."
  28. Shakun et al. Clarify the CO2-Temperature Lag
    Great article. This is a paper, like the one by De Conto et al. about the permafrost/PETM linkage, that deserves considerable attention. Taking them together, I think it's fair to say that we continue to collect evidence that the Earth System is itself "wobbly" or "twitchy", thanks to the cascade of effects that can be unleashed by even a "minor" perturbation. We may be in the process of learning that the relative equilibrium that's held throughout human history was a much more precarious balance than we generally assumed, especially those of us who are not climate experts. The implications of this inherent nature of our environment, assuming our dawning realization is correct, are very grim. They tell us that not only does it take less of a shove to knock the Earth System out of its state of equilibrium, but that once that move to a new equilibrium state (or excursion through state-space in search of a new eq.) begins, it's extremely hard to reverse the process. You can go home again, but it's much harder than we thought. For those who like physical analogies, I always think of a ball resting in the bottom of a bowl. Poke it, and it rolls around a bit but returns to (virtually) the same position. This is how we prefer to think of the Earth System. But it's looking more and more like the ball is instead resting in a shallow depression on top of an inverted and very irregularly shaped bowl; nudge it very gently and it rolls around and comes to rest in its perch. But even a moderate poke sends it over the edge and going who knows where. And not to go all Jared Diamond about it, but I think there's a strong case to be made that the basic geography of the Northern Hemisphere loads the dice in favor of rapid warming events -- all that land at just the right distance to accumulate and then release carbon, surrounding open ocean that can quickly lose ice cover and kick off the albedo flip positive feedback.
  29. Shakun et al. Clarify the CO2-Temperature Lag
    @Michael: 1) Orbital change causes insolation increase in Northern and Southern Hemisphere summer. 2) Northern Hemisphere glacial ice caps melt rapidly enough to overwhelm thermohaline circulation. 3) Loss of consistent, global Thermohaline heat redistribution leads to loss of the ability to redistribute heat efficiently. 4) loss of heat redistribution is magnified in the Southern Hemisphere because of the relatively large percentage of earth's surface covered by ocean. The Southern Ocean warms up enough to release large volumes of CO2. 5) The rapid and large-volume increase in atmospheric CO2 feeds back to increase overall global temperature. Simply put: Orbital forcing leads to larger heat inputs at the poles relative to equator. The ensuing melting releases CO2 and fresh water. The fresh water disrupts thermohaline circulation, trapping heat in the oceans that would otherwise be redistributed. The CO2 released feeds back into the increasing temperature/heat greenhouse effect. If this happens fast enough, the CO2 and temperature/heat increases can rapidly overwhelm the negative feedbacks from weathering and organic sequestration....
  30. 2012 SkS Weekly Digest #14
    Alces - "We have those plants. They are called trees. The output is wood. Why not grow more trees and sequester more carbon in wooden structures? When wooden structures reach the end of their lives, why not recycle the wood, perhaps as a biofuel?" Because when they get used as biofuel, or the trees otherwise decay, the carbon goes right back into the atmosphere. True sequestration will require keeping that carbon locked away (as coal, oil, and natural gas did) for tens of thousands of years while the carbon cycle and silicate weathering absorb the pulse of carbon we have released. That sequestration requires an increase of long term carbon mass kept from the atmosphere - at this point we simply don't have enough land area (even if, say, we stopped growing lower carbon density food) for high density forests sufficient to pull our current CO2 overburden out of the atmosphere.
  31. DeConto et al: Thawing permafrost drove the PETM extreme heat event
    Great article and useful links. FYI, the Paleogene Period consists of the Paleocene, Eocene, and Oligocene Epochs.
    Moderator Response: (AS) Oops. I'll fix that, thank you.
  32. threadShredder at 23:30 PM on 10 April 2012
    Fred Singer Debunks and then Denies
    @Moderator Response @16: I understand your policy and, of course, will abide by it. But it is a losing one. You clearly understand this is a war, and not a debate. The best way forward is to respond to deniers with the science and then you have to question their personal integrity when they refuse to respond rationally.
  33. Michael Whittemore at 21:22 PM on 10 April 2012
    Shakun et al. Clarify the CO2-Temperature Lag
    I read the link, very informative, thanks. Just so I am clear, stopping of the (AMOC) forced the Southern Ocean to release CO2 which caused this feedback system. It was not the temperature rise in the southern ocean that caused it but the extra CO2. This CO2 had a g value of 0.8 leading to a 5 degree temperature increase?
  34. Shakun et al. Clarify the CO2-Temperature Lag
    Michael Whittemore @29, actually there is a much simpler explanation. Once the initial warming had commenced, it started a feedback cycle. The effect is that the first degree of warming causes feed backs which result in an additional g degrees warming. These in turn result in an further feed backs resulting in g^2 degrees warming, which in turn result in further feed backs, which cause an additional g^3 warming, and so on. So long as -1 < g < 1 degree C the consequence is a self damping cycle. That is because |g^x| < |g^y| where y > x whenever -1 < g < 1. As it happens, even the sum of an infinite series of such diminishing values will be finite. Consequently, the temperature increase from a given impetus will close in on some finite increase above the original and stabilize at that value, absent new forcings. For the glacial/interglacial transition, we are talking about slow feedbacks, for which the relevant value of g is about 0.8, leading to approximately a 5 degree increase in temperature after feedbacks from an initial one degree increase. So it is not necessary to find some mechanism which weakens the feedback cycle to bring the warming to an end. It will do so naturally so long as g < 1. This is all explained here. As a side note, some fake "skeptics" insist that any positive feedback must end in a runaway effect. They are making exactly the same logical fallacy as was made by Zeno in his famous paradoxes.
  35. Michael Whittemore at 18:42 PM on 10 April 2012
    Shakun et al. Clarify the CO2-Temperature Lag
    So with the reduction of CO2 by Silicate weathering, this stopped the warming in the Southern Hemisphere, which in turn stopped the release of CO2 from the ocean. This would have allowed the planets global temperature to become in balance. So the Atlantic Meridional Overturning Circulation (AMOC) played no part in cooling the Southern Hemisphere, Right?
  36. Eocene Park: our experiment to recreate the atmosphere of an ancient hothouse climate
    Adelady:
    ...do we really know the physiological limits for bees and bats and the other small critters we rely on for crops?
    For many we do, or we can easily infer from various distribution analysis methodologies. And your second point is right - our own physiological limits will be severely tested if we pass temperature limits affecting a pollinator species for a major food crop - or indeed that affect any specieas that performs any of the myriad ecological services to which most humans are completely oblivious. This is the basis of my second point at #16,and it is a part of the reason why I try to emphasis that humans are adapted to a certain specific mean global temperature range. Anyone who wants to suggest that we can easily adapt to higher temperature conditions needs to explain exactly how we drag along in that adaptation the rest of the biosphere on which we depend. Humans are not an ecological island, no matter how much a huge swathe of our species imagines otherwise, and omitting such facts from a fantasy future of easy adjustment favours nothing but the imaginations thus assuaged.
  37. Eocene Park: our experiment to recreate the atmosphere of an ancient hothouse climate
    "Direct physiological constraints are not the entirety of the story, but neither are they least amongst them." Maybe not for us. Leaving aside the issue of oil-based fertilisers, do we really know the physiological limits for bees and bats and the other small critters we rely on for crops? Our own physiological limits will be severely tested if we suddenly pass some temperature limit affecting a pollinator species for a major food crop.
  38. 2012 SkS Weekly Digest #14
    Please, can Caerbannog's posts here be reposted as a separate and distinct thread? The elegance deserves it's own platform here.
  39. Doug Hutcheson at 16:36 PM on 10 April 2012
    2012 SkS Weekly Digest #14
    How optimistic are you that the human race will get its act together in time to stave off catastrophic climate change?
    Nothing will be done until the momentum of public opinion is sufficient to overcome the inertia of vested interests, both political and commercial. The inherent difficulty in developing a velocity in public opinion through education (by definition, half the population has below average capability of understanding the problem) means that it will likely be a long time before the (velocity * mass) of public opinion reaches the critical momentum. The only hope for a swift change in public opinion lies in the occurrence of a crisis so great that everyone can see and interpret the evidence. Failing such a crisis, I have no expectation that opinion leaders will allow public perception to be led in a direction that would mandate prudent and timely action. Without such action, climate change is likely to adversely impact the ability of humanity to maintain its current level of societal sophistication. Whether this would be classed as a catastrophe is subjective. If a large fraction of our species was to die off and a large fraction of our current technology was to become unsupportable, I would class this as a catastrophe. YMMV.
  40. 2012 SkS Weekly Digest #14
    #18, you're trying to distract from the fact that your original comment and snide dig at SkS, IPCC and Joe Romm is incorrect. The cartoon does not mention losses, normalised or otherwise, it mentions "increased extreme weather". The best evidence we have, summarised by IPCC, also in numerous posts here, such as this one on Hansen et al 2011 is that actual extremes are increasing, both of temperature and precipitation. I don't suppose you'll be honourable enough to retract your snide comment at #12? Discussion of hurricanes and tornadoes here is an off-topic distraction, also these events are less important to the majority of world population that does not live in the path of these particular flavours of extreme weather - floods and droughts are much more globally relevant.
  41. 2012 SkS Weekly Digest #14
    "If we had plants that created coal as an output, or in some other fashion sequestered the CO2 for the long term, that would be great..." We have those plants. They are called trees. The output is wood. Why not grow more trees and sequester more carbon in wooden structures? When wooden structures reach the end of their lives, why not recycle the wood, perhaps as a biofuel?
  42. 2012 SkS Weekly Digest #14
    @#15 Skywatcher -- I agree that there is indeed an upward trend in weather and climate related losses. This is to be expected as the population and economy expand. Normalization of the losses is an attempt to extract the underlying trend, if any, in climate. Of course looking directly at weather and climate statistics is a more reliable way to determine trends in climate. There is no trend in tornadoes (which is the extreme weather depicted in the cartoon), except for the increase in observed weaker tornadoes. This is to be expected as the observation network has changed dramatically with the installation of a doppler radar system across the USA. There is no trend in the stonger (EF3 and above) tornadoes, for which there is a more reliable record. Similarly, there is no trend in hurricanes, once the change in observation systems is taken into account (early records are land based and occasional ship reports. Then airplanes were used to observe known systems, and then finally satellite monitoring started.) A recent paper gives more details, with the conclusion of "Our analysis does not indicate significant long-period global or individual basin trends in the frequency or intensity of landfalling TCs of minor or major hurricane strength. This evidence provides strong support for the conclusion that increasing damage around the world during the past several decades can be explained entirely by increasing wealth in locations prone to TC landfalls, which adds confidence to the fidelity of economic normalization analyses." Historical global tropical cyclone landfalls, Journal of Climate. And yes, there has been observed trends in temperature extremes, although not nearly as strong as many claim, because daily temperature distributions are significantly non-normal. Trends in extreme precipitation events, are currently a subject of investigation and debate.
    Moderator Response: [JH} With all due respect, I believe that you are taking the cartoon way too literally. There is nothing to indicate that Tooles meant the cartoon to reflect today's conditions. When I looked at it for the first time, I projected the scene to be occurring in 2050.
  43. Book review of Michael Mann's The Hockey Stick and the Climate Wars
    I've finished the book over the Easter, and (only thereafter) deservedly so, put a five star review on amazon. Also, I've sent a short email of appreciation to MM himself (acknowledged with thanks), because I think MM deserves all friendly supports that he receives after the the amount of smear and bullying he was subjected to. Enduring the attacks of the denial machine was not easy task. The contrarian's focus on MBH98-99 was as silly as their arguments against AGW in general, so MM as the lead author was under big pressure defending not just himself but virtually the whole climate science. The account of the events is good, supported by numerous notes to follow up if required. The narrative is also good.
  44. 2012 SkS Weekly Digest #14
    Further, as an antipodean, I would appreciate maps of station sites that show the entire globe, and not just the North Atlantic and surrounding lands.
    OK, I don't want anyone to accuse me of being a dogmatic Northern Hemisphericist.... ;) So for all the good folks down under, here ya go: For what it's worth, feel free to pass the material that I've posted here around to friends/relatives/co-workers/etc... -- I hit one of my "fence sitting" relatives with it a couple of days ago, and it seemed to make a real impression on her. The fancy Google Earth "eye candy" does seem to help drive home the message.
  45. 2012 SkS Weekly Digest #14
    How optimistic are you that the human race will get its act together in time to stave off catastrophic climate change?
    Those readers who have followed my comments here and elsewhere for the last few years will know that I have been growing ever more pessimistic. Over the last few weeks I have reached the conclusion that humanity will not solve the carbon emissions problem, and that barring global pandemic and/or major global warfare, we will eventually burn as much of the fossil carbon accessible to us as we are able. Nuclear technology will not help, nor will other imagined technological fixes. The laws of thermodynamics preclude what is essentially a magical skipping over both the amount of energy that we have access to, and the pushing against entropy that would be required for high technologies to operate. Just go to the IPCC's worst case scenarios, and one will see what the most likely future is for the planet. Barring a political miracle, all the rest is arrant optimistic fluff.
  46. Eocene Park: our experiment to recreate the atmosphere of an ancient hothouse climate
    And as an addendum, Andy S's observation about the rapidity of global warming is an important factor in how humans are - or are not - able to adapt as a species. Individuals will always be able to adapt to changes in temperature, but at the species level rapid temperature change is very undesirable. This leads to (or rather, stems from) discussions of the Holocene constancy that led to the development of agriculture and concurrently of human civilisations, but such has been described elsewhere and probably doesn't need to be repeated here.
  47. Eocene Park: our experiment to recreate the atmosphere of an ancient hothouse climate
    dr2chase. It was genuinely not my intent to exacerbate your grumpiness. Perhaps you need to understand that as an ecologist I am looking at this in a slightly different context to the "next election cycle", or the "next house move" time frames that most Western people are inclined to employ. You mention individual people's abilities to adapt to local changes. I tipped a hat to this at the top of the post at #16. Certainly, no-one disputes that individually, and at local spacial scales and at certain temporal scales (days to years), humans have an amazing capacity for adaptation, temperature adaptation included. The problem for us as a species is greater than this, however. It might be worth re-reading my previous points and dwelling on them carefully, because they encompass some profound challenges to humans that render less impressive our current abilities to tolerate extremes of heat - and indeed of any weather type. Fact: oil will run out. Functionally, and globally, probably within half a century. Social/technological unpreparedness, and the resulting social/economic havoc that will ensue as shortages start to bite, might bring the effective functional end closer than around that ball-park estimate of half a century. Our industrial food production paradigm is implacably based on the production of nitrogen fertilisers derived from fossil fuels. Without oil the easiest feedstock with which to manufacture fertiliser disappears. Coal can be converted to other forms, including synth-oil, but a lot of (currently non-existent) infrastructure is required, and there is a thermodynamic cost to deriving the converted energy density. Thus the energy-return-on-energy-invested (ERoEI) from converting coal is lower than with oil-based feedstocks, and this in itself has profound technological and economic consequences. Frankly, humans have probably already left it too late to attempt a smooth transition to a non-oil based economy, whether one is considering food production, electrical power supply, fuel-based temperature regulation in buildings, or transport. Further, without full exploitation of coal there is little chance that our civilisation as we currently recognise it will continue into the future*. Where does this leave the younger amongst us, and our yet-to-be-born decendants? Basically, without the technologies that we currently use to manufacture textiles, to generate warmth (and coolth) and to keep everyone's neighbours from eyeing off any useful thing that they might have squirrelled away. In the near future a climate that is two or three degrees warmer might simply be a bit more of an inconvenience under a contracting economic regime, but it will grow ever more noticable as the extremes impact directly on our communities, and as the ecosystem services on which we rely (including a nacently non-fossil fueled agriculture) start to through curve balls at us. We might not as a species all die of heat exhaustion (in fact, few of us will), but many are still going to be directly and severely impacted by the increased heat extremes that the planet will experience. And by other indirect extremes, such as drought and flood, that come from heating the planet. And remember that this is going to happen with a loss of ability to manufacture industrial scales of food... Even then we won't plunge directly toward extinction. We might not lose even more than, say, around half of the peak human population before we accept a much-reduced standard of living, and decide to go hammer and tongs at the coal no matter that it's a Faustian bargain. And Faustian it would be. If humans do end up burning all of the coal on the planet (and current socio-political trends indicate that we will), then the final increase in mean global temperature will be in the range of 6 degrees celcius, or more. Even if we decide to forebear our current inclination to burning coal future, more desperate generations might not be so restrained, and may not recognise the lessons of Angkor, Easter Island and other such civilisations. In a climate that warm the extent of human-habitable regions will be much reduced, and certainly heat limits to human physiology will be a significant component of this fact. Add to this the requirement for ecosystem functions necessary for human survival, and that probably require similar climatic conditions to humans, and suddenly there's little room to squeeze in much of a niche for us as a species. In the end it's a whole suit of factors that combine to make any significant planetary warming undesirable for humans. Direct physiological constraints are not the entirety of the story, but neither are they least amongst them. [*Nuclear energy is not going to save us, but that's a topic for a different discussion.]
  48. Shakun et al. Clarify the CO2-Temperature Lag
    mdenison @ #8: The nonlinear response of the climate system would indicate that the rate of change of a variable, such as CO2 (and methane and N20) is just as important, if not more so in determining some final equilibrium state. The natural feedback mechanisms (biological & rock weathering) to maintain CO2 in a range can be overwhelmed, leading to an increasingly unstable system that will rapidly pass through a series of potential "tipping points" that are unpredictable by any model. The dramatic loss of sea ice in 2007 might be one such point, when at the time, it was seen as a "black swan" event, we see, only after the fact, that 2007 was no one-off black swan, but rather a new sharpening downward trend in Arctic Sea ice. Even in analyzing 2007's amazing summer low (which of course came close to being beaten in 2011) fingers were pointed an proximal causes, such as anomalous winds, currents, etc. When, from a wider perspective we now can see as part of a new normal in this rapidly evolving Anthropocene. The sharpening downward trend not predicted by any climate model as such tipping points can only be seen after the fact. An excellent article on this can be found at: http://www.pnas.org/content/105/6/1786.full.pdf+html Other such tipping points, only seen after the fact might well be events such as the Russian heat wave of 2010 and this March heat wave of 2012. Though the proximal causes might be found in unusual blocking events, we might find that the new norm of the Anthropocene is toward more frequent and intense blocking events. There is nothing in the last several million years remotely like what the Anthropocene is now evolving into, and no model will be able to forecast the nonlinear responses to the rapidly changing atmospheric composition of the planet(rapidly by all geological standards). Going to 560 ppm of CO2 in a few hundred years will have a different set of tipping points than going there in 10,000 years as the feedback response in each case is vastly different.
  49. 2012 SkS Weekly Digest #14
    #12 - interesting that in the same paragraph of the report we have:
    There is high confidence, based on high agreement and medium evidence, that economic losses from weather- and climate-related disasters have increased (Cutter and Emrich, 2005; Peduzzi et al., 2009, 2011; UNISDR, 2009; Mechler and Kundzewicz, 2010; Swiss Re 2010; Munich Re, 2011).
    There is then a significant discussion of the confounding factors as well as increased exposure to losses which prevents a discernible climate signal in normalised losses. That you chose normalised losses is the problem here. You have selected the most challenging metric (for attainment of statistical significance) with which to criticise the cartoon, and as we'll see below, missed the mark anyway. The cartoon comment is about actual increased extreme weather and not normalised losses, so the cartoon is fairly accurate. Chapter 3 of the IPCC SREX report is the one you need to look at if you wish to criticise the cartoon. Here, we have:
    In many (but not all) regions with sufficient data there is medium confidence that the number of warm spells or heat waves has increased since the middle of the 20th century (Table 3-2).
    and a more extensive quote from 3.3.1:
    The AR4 (Hegerl et al., 2007) concluded that surface temperature extremes have likely been affected by anthropogenic forcing. This assessment was based on multiple lines of evidence of temperature extremes at the global scale including the reported increase in the number of warm extremes and decrease in the number of cold extremes at that scale (Alexander et al., 2006). Hegerl et al. (2007) also state that anthropogenic forcing may have substantially increased the risk of extreme temperatures (Christidis et al., 2005) and of the 2003 European heat wave (Stott et al., 2004).
    On precipitation (3.3.2):
    Based on evidence from new studies and those used in the AR4, there is medium confidence that anthropogenic influence has contributed to intensification of extreme precipitation at the global scale.
    Readers are left to decide for themselves if they still think the IPCC should be inside or outside the bunker in the cartoon...
  50. Eocene Park: our experiment to recreate the atmosphere of an ancient hothouse climate
    dr2chase: I am sure that even in the most extreme scenarios, there will be places on the planet, at high latitudes or high altitudes, where humans will be able to live in some kind of self-sufficient manner with a modified form of our current agriculture. The question is whether these places will be large enough and connected enough to support the kind of specialized economies and trade that have raised standards of living and quality of life; at least for the most fortunate of us in developed countries. What particularly concerns me is the pace of the forced change, both for the physical environment and for our civilization. If this transition were taking place over tens of thousands of years, hundreds of human generations, I'd be fairly comfortable with it. Cities would have to be rebuilt several times over anyway, so sea level coming up fifty metres or so would be no big deal. Slow migrations and small changes in fertility could redistribute the population without major suffering. Advances in agriculture and technology would likely ease the transition. This change we are inflicting isn't a gentle wind gradually pushing the global supertanker off course, but, rather, an impact with a reef. It the suddenness and unpredictability of the coming changes that bothers me--the probably ugly consequences of forced adaptation over the next couple of centuries--not the unlikely prospect of the entire extiction of Homo sapiens in the longer term.

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