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Unforced Variations: Nov 2012

Filed under: — group @ 1 November 2012

I can’t think what people might want to talk about this month…


476 Responses to “Unforced Variations: Nov 2012”

  1. 151
    Hank Roberts says:

    Who is supposed to have said this? I didn’t.
    Search doesn’t find the text quoted.

    “First of all almost all the ice has to melt to return to a Pliocene climate state.”

  2. 152
    Dan H. says:

    Pikkles,
    Antarctic glacial formation started prior to the Pliocene epoch. While the forests of Greenland disappeared during this glaciation period, Antarctica was a massive ice cap ~30 millions of years prior.

    During this time period, glaciers advanced and ebbed on ~40 kyr timeframes, as opposed to the current 100 kyr. The West Antartic ice sheet expanded and contracted accordingly.
    http://www.nature.com/nature/journal/v458/n7236/full/nature07867.html

  3. 153
    wili says:

    “That’s “2XCO2″ — not cause for despair”

    Hank, please inform me I have ever declared that we must all despair. If you cannot, please refrain from imputing to me statements I have never made.

    What we certainly need to do is stop making the problem much worse. But even this seems to have been beyond our collective grasp so far. We can only hope (and work to make sure) that a new legislature and a new raised awareness thanks to Sandy and Alice, may lead finally to some real forward motion on a national level toward effective action, and then on a global level. Meanwhile, let’s keep working to inform ourselves and others of the science, and save our greatest vitriol for the real denialists. (And please everyone, can we stop constantly feeding obvious actual trolls–saturated wavelengths??…can’t they at least try to come up with something new?)

    (reCaptcha: vulgifi Soot-Free !)

  4. 154

    “(And please everyone, can we stop constantly feeding obvious actual trolls–saturated wavelengths??…can’t they at least try to come up with something new?)”

    IMO, sometimes it’s not so obvious when somebody is asking a real question (with real openness to consider answers) vs. trolling–especially ‘concern trolling.’ My default is to assume good faith initially: whatever the probabilities of one vs. the other may be, there is much more upside to giving the most educational answer you can, and much downside to dissing someone unjustly.

  5. 155
    Jim Laughter says:

    Climate change? You better believe the climate is changing, and not just politically. Weather patterns, global temperatures, worldwide storm systems, unprecedented carbon dioxide levels — a whole new way this old world is going to have to look at our environment. But where will the survivors of the pending global disaster go to reestablish the human race? Read about it in my recently released climate thriller, Polar City Red.

    http://www.amazon.com/Polar-City-Red-Jim-Laughter/dp/1620160064/ref=sr_1_1?ie=UTF8&qid=1352389550&sr=8-1&keywords=polar+city+red

  6. 156
    pikkles says:

    Dan H.

    The two papers below tell a somewhat more complicated story of Antarctic glaciation. Fairly recent (i.e. Miocene) substantial amounts of Antarctic vegetation appear to have existed.
    http://www.geo.umass.edu/climate/papers2/pekar_deconto1.pdf
    http://xa.yimg.com/kq/groups/18383638/2101921172/name/ngeo1498.pdf

    note:
    “The temporal distribution of pollen and spores indicates that local vegetation was tundra with small trees growing in protected areas throughout the middle Miocene. This type of vegetation indicates that the climate was somewhat cooler than that found at the modern austral polar alpine tree limit (less than 10 C in the warmest month), which today is best represented in the southerly Chilean Andes.”

    Trees such as the southern beeches and podocarps that today grow in Chile and New Zealand and other temperate Southern Hemisphere areas are of the same genera and differ very little from their ancestors that grew on the continental crust of Eocene, Oligocene and Pliocene Antarctica.
    The situation is similar in the northern hemisphere. Macrofossils and fossil pollen of modern angiosperm tree genera, easily recognizable as maples, walnuts, chestnuts, hazels, elms, katsura, beech, sassafras, oak etc., i.e. trees that today grow only at temperate mid-latitudes, have been found on Ellesmere Island, Greenland and other places near and even well north of the Arctic Circle.

    Tree evolution is relatively slow, generally speaking, and present-day ranges are not due so much to recent evolutionary adaptations as to shifts in ranges in response to climatic changes, which have been massive and rapid at many points during the Quaternary.

    This should give us at least some basic hope for the future in terms of the ability of ecosystems to adapt to warmer global conditions, despite the oft-heard, vague declaration that life on earth is not evolved for a non-Quaternary world.
    That may well be true for polar bears and penguins, but in fact, most species on earth today are adapted to warmer conditions, with biodiversity centered in the warmest regions. This biodiversity may, amongst other factors, in part be due to the fact that warm regions have longer histories of existence on earth, and were wider spread in the past.

    It may not be in fashion to be optimistic about the future, but I personally think there are some very good reasons not to despair even if we fail to bring CO2 and temperature down.

    [Response: Oh yeah, and about that 20m rise in sea level? - gavin]

  7. 157
    pikkles says:

    gavin-
    i don’t mean to be a pollyanna about it. sea level rise is of course not something anyone’s optimistic about, especially members of the large percentage of humanity who live in permanent coastal dwellings. i would not argue that warming does not present unique challenges for 20th century human civilization.
    modern man and the natural world survived the last glacial termination and the 120 meter sea level rise that occurred during that process, but of course, we were living in small huts at the time.
    the shock to our political system may cause us to blow our wonderful selves to smithereens.

    but i am saying from an ecological standpoint, a quick 20 meter rise and the accompanying massive rapid shifts in climate has happened before very recently in evolutionary history.
    see below:
    http://userpage.fu-berlin.de/geodyn/tutorials/Physik_der_ErdeII/pdf/Hanebuth-etal2000_science.pdf

    a question: do the most dire predictions for the coming 3 centuries anticipate sea level rise equivalent to that of the above paper (i.e. 16 meters in 300 years)?
    surely the sort of melting episode described in the above paper has occurred dozens if not hundreds of times over the course of the Quaternary, probably on even larger scales.

    of course there are also issues of plant migration through drastically altered human landscapes such as the US midwest.
    But there again, plants have migrated through extremely disturbed and inhospitably post-glacial environments in the past. And our own agency will certainly be able to help with the transportation of seeds if necessary.
    Assuming we’re not all busy destroying each other…

    [Response:Using the term "very recently" to refer to something that happened 14.5k years ago, given the changes in human societies since then, is not a fair use of the term. And tree species migration is not the only, nor even principal, ecological problem that's going to arise in response to this climatic change--far, far from it. Look at what's happening to high elevation pine forests in the western USA right now, under relatively minor warming (compared to possible/predicted if insufficient actions are taken), and the feedback effect that's having, and going to have, on the snowpack and corresponding spring temperatures and stream hydrology--just as one very off-the-cuff example. We have over 7 billion people on this planet, intermixed with and dependent on both natural and managed ecosystems. A bit more resolution as to the nature of the actual and potential problems just might be in order.--Jim]

  8. 158
    pikkles says:

    “21st” century civ. that is…

  9. 159
    Hank Roberts says:

    New evidence for bipolar seesaw link between Greenland and Antarctica – and abrupt climate variability

    is another interesting one at bitsofscience; thanks Gavin for pointing to that site inline above for the sea level paper.

    Is bitsofscience a candidate for the sidebar?
    It could replace the late lamented Head in a Cloud that’s gone 404

  10. 160
  11. 161
    Hank Roberts says:

    Sorry if I misread your mood, Wili, I responded to your post abov with the phrases
    “deeply troubling” and “dire information” and “despair-provoking” in it.

    Someone earlier posted “I’m in despair. Is it justified?”
    and Gavin replied: No.

  12. 162
    pikkles says:

    I think there is a philosophical conflict within common modern popular and public ethics of climate change.
    on the one hand, there is the non-anthropocentric ethical dogma that we are doing a bad thing simply by intervening with the “natural” course of climate and upsetting a perceived natural balance, or some sort of natural course of events that ought to occur.
    on the other hand, i don’t think anybody but the deepest deep ecologist or Voluntary Human Extinction Movement member would say that in the coming millenia as a species we ought to sit back and let the earth descend gradually (and at times perhaps not so gradually) into another glaciation, as climate has done for the entire Quaternary Period and beyond in the past.

    In other words, we are ethically opposed to “messing with nature”, but we would almost certainly not be opposed to “messing with nature” if the relative climate stability of the Holocene began to deteriorate into the next glacial cycle.
    One look at the Vostok (or any other 100ka scale Quaternary core) should suffice to show that we are living at the tip of a brief and extreme spike of warmth, which is not at all likely to remain stable for more than a few millenia in the future.

    [Response:Only a few millennia??. Well thank goodness, we ought to be able to wait that out.--Jim]

    The idea that the earth has changed only gradually in the past and that the changes we are causing now are unprecedented is at this point an archaic notion as this paper demonstrates. Post-industrial global warming is only unprecedented in terms of rate and total change within the past ~3-4,000 years, if that. It is also (if it continues on its present course) unprecedented in relation to maximum global temperatures of the Late Quaternary, but the warmer world to which we will presumably return has very recent analogues in Cenozoic. It is likely that a return to globally warmer conditions would have occurred anyway at the end of the current “icehouse” phase of earth. it is purely arbitrary from the perspective of a snapping turtle that we happen to be the cause of it now.

    I think those of us devoted to reversing climate change should be straightforward about the fact that the end goal for humanity with regard to climate is pure geoengineering, with the aim to keep the global climate as stable and static as possible for as long as possible, even given the likely opposite threat in future of “natural” global cooling. We should abandon the romantic and, at this point, given what we now know about recent Quaternary climate variability, irrational notion that just by warming the globe we are doing unjustifiable harm outside of the human realm of Holocene-based, 21st-century-based civilization, by moving the earth away from Quaternary cycles.

    [Response: Oh yes, preventing the next ice age should be at the top of our most pressing concern list. Not. But now that we've done that, what next? - gavin]

    [Response:Seriously, what are you talking about?--Jim]

  13. 163
    pikkles says:

    Jim
    You wrote, “Look at what’s happening to high elevation pine forests in the western USA right now”
    I assume you are referring mainly to the bark beetle infestations of lodgepole pine forests, or perhaps white pine blister rust in western white pines. I’m sure there are other pine forest issues in the west at the moment. I do not deny that such changes are taking place, and that such ecological changes will probably increase if the climate warms at a faster rate in future.

    [Response:No not just lodgepole pine, although that's certainly the hardest hit. Also the decimation of many whitebark pine stands, and potentially other species from the mountain pine and other bark beetles.]

    However, I think it is short-sighted to think that this is unusual in terms of the ecological histories of tree species. i and many paleoecologists would argue that naturally occurring ecological upheaval and chaos has been and still is a lot more common and severe than it is commonly perceived to be. for some reason we tend to think of ecological change as static and gradual

    [Response:No, we don't. We're well aware that ecological dynamics can be dynamic and rapid. And unpredictable. Indeed, that's a very big part of the concern here.]

    when even in the last millenium before the industrial revolution plants and animals were still rapidly migrating in all directions due to non-anthropogenic causes. in new england, for example, tree species are still arriving from their southern glacial refugia. American Chestnut, to name just one example, only arrived in Connecticut ~1500 years ago, although it is considered a “native” of the area.

    [Response:Not correct, but more importantly, not really relevant.--Jim]

    in north america at the last glacial termination, the rate of climate change was at times much faster than at present, and the ecological changes that it wrought on pine forests and other forests at the time would have dwarfed those of the present day. it would have (and almost certainly did) come in the form of “native” beetles, fungal disease, moths, etc., as rapid climate change drastically changed the optimum ranges of tree species outside of their ideal conditions. speeds of tree species migration were far beyond what we are seeing with the present mild warming.

    [Response:You're not getting the point. How unique the current dynamic is, is NOT the central point. The issue is rather the degree of disruption liable to occur on a populous and developed and dependent planet. It doesn't matter what happened thousands of years ago, except to inform us as a very rough guide. It hardly even matters what happened 100 years ago. It's not the same world we live in. And the warming is not mild--it's extremely rapid--Jim]

    here’s a good paper attesting to that fact.
    http://www.mathstat.ualberta.ca/~mlewis/publications/25Clark1998B.pdf

    [Response:A significant piece of evidence addressing "Reid's Paradox" and high migration rates came a few years ago wherein molecular evidence lent strong credence to the idea that multiple refugia likely existed fore of the advancing front of the core ranges of many tree species under climate change.--Jim]

    i agree that the rapid global changes 14,500 years ago were beyond the ken of modern civilized humanity. our whole civilized history is contained within the relatively (but by no means absolutely) stable climate of the past 10,000 years. for that purely anthropocentric reason we should take steps to curtail anthropogenic climate change, or at least attempt to keep the rate of change gradual.

  14. 164
    Troy_CA says:

    Chris Korda #138,

    I believe the RCP scenarios refer to the anthropogenic forcing change relative to pre-industrial times by year 2100. So, for example, RCP 8.5 means a forcing change of 8.5 W/m^2 in 2100 relative to pre-industrial times, or over 2 doublings of CO2 (requiring around 1380 ppm in 2100 if the only forcing were CO2).

    “I became increasingly curious about three questions: 1) Assuming we emit an additional teraton of CO2 by 2035, what average global surface temperature will likely result? 2) Why do the AR5 scenarios omit temperature data (unlike the AR4 scenarios), despite this being what most people presumably want to know?”

    I recommend you look at the CMIP5 scenario runs at Climate Explorer, which makes processing of globally averaged fields easy: http://climexp.knmi.nl/selectfield_cmip5.cgi?id=someone@somewhere. Temperature is most certainly included in the output of these runs (tas). For the RCP 8.5 scenario, taking the mean of 1 run per model yields a trend of 0.32 K/decade over the 25 years from 2011 to 2035, or about 0.8K change over that period. However, keep in mind that this mean also shows an 0.26 K/decade trend over the last 25 years, despite GISS only showing a trend of around 0.16 K/decade.

    “If “RCP8.5 is reality” and CM3 is to be believed, we could face an increase in average global surface temperature of ~1.5ºC between now and 2035″.

    Hmmm, this is not quite right. GFDL CM3 is certainly on the high end, showing a trend of 0.45K/decade from 2011 to 2035, which corresponds to about 1.13 K increase. However, again keep in mind that this same model showed an 0.39 K/decade trend over the most recent 25 years , compared to the actual trend of 0.16 K/decade for GISS.

  15. 165
    tokodave says:

    157 and Jim’s reply. And then of course, there’s the elephant in the room that Jim alludes to: we don’t live in the LGM, Miocene, the Pliocene, the PETM, or whenever else. We live here and now and this is the only climate we’ve got. The world’s societal and agricultural infrastructure has developed in response to the climate we have (or perhaps more appropriately, used to have…). It’s worth repeating the closing statement from the 2012 AMS Climate Change Statement: Prudence dictates extreme care in accounting for our relationship with the only planet known to be capable of sustaining human life.

  16. 166
    pikkles says:

    gavin,

    i suppose it’s reasonable to assume that if we become capable of the global organization and energy required to remove CO2 and cool the globe, we will be able to do the opposite if we are faced with the threat of glaciation (which, although natural, all-natural, would not be good for most forms of earthly life, including us)
    however, beyond asking heck of a lot in terms of global cooperation and the energy required to remove anthro CO2, that also assumes that we can emit enough CO2 in order to avoid the next glaciation.
    Are we sure beyond a doubt that that is the case?
    Even in the Pliocene, which as i understand is thought to have had higher atmos. CO2 levels than present, there were still glacial cycles, albeit much more moderate than those of the late Quaternary.

  17. 167
    pikkles says:

    Hank Roberts
    In post #149 I mistakenly attributing to you the quote “First of all almost all the ice has to melt to return to a Pliocene climate state.”
    That ought to have been directed at David B. Benson’s comment #137
    My apologies.

  18. 168
    pikkles says:

    tokodave,

    you also wrote, “The world’s societal and agricultural infrastructure has developed in response to the climate we have (or perhaps more appropriately, used to have…)”

    this is also true, but that fact does not mean that we will not be able to farm and have societies in a pliocene-like world.
    many of the world’s most fertile farming regions, the midwest of north america and northwestern europe for example, were taiga, tundra or under ice at the last glacial maximum. many of the regions that may become warm enough to farm in the future are at present taiga and tundra with permafrost.
    not to mention the facts that increased moisture in the atmosphere, increased rainfall, decreased global aridity, and increased warmth are all likely to boost global food production.

    [Response:Right, not to mention those "facts".--Jim]

    decreased land area from rising sea levels will, on the other hand, decrease arable land area.

    change is unsettling by definition, but it is not necessarily bad, and certainly not necessarily apocalyptic, just because things become different.
    what worries me the most is not so much ecological destruction as the possibility of large-scale and possibly nuclear war as political boundaries are forced to change and people are forced to move.

  19. 169
    wili says:

    No prob, hank. Thanks to that bitsofscience link. I second your mostion to add that site to the sidebar.

    (reCaptcha “needAjoy now”–is it telling me to go out and have a beer?!)

  20. 170
    Ray Ladbury says:

    Pikkles, waxing nostalgic for the good ol’ days of the Pliocene, are we? I would note that you really need to distinguish between the early and late Pliocene. Dave is certainly right about the early Pliocene.

    Also, past climate change epochs did not see anything like the rapid change we are seeing now on a GLOBAL scale.

  21. 171
    Hank Roberts says:

    > enough CO2 in order to avoid the next glaciation.

    No worries: http://scholar.google.com/scholar?cluster=12991617425286636548&hl=en&as_sdt=0,5

    Besides, there are more powerful greenhouse gases:
    http://www.epa.gov/highgwp/scientific.html

  22. 172
    Chris Korda says:

    Troy @164: Thank you very much, not only for the link, but also for alerting me to a serious error in my annotated CM3 temperature chart. The 2013 line was misplaced on the time axis by a whole decade, resulting in overstatement of the temperature increase by about half a degree. My eyes aren’t what they used to be I guess! Here’s the corrected chart, showing an increase of ~0.9ºC between now and 2035, which corresponds more closely to the “1.13 K increase” you mention.

    The historical data shown in the CM3 graph appears to differ significantly from the
    GISS Land-Ocean Temperature Index. I assume this is because the “historical” portion of the graph is showing not observations but CM3′s modeling of historical temperatures?

    Re RCP2.6: If I understand correctly our forcing increased sufficiently during the AR5 process to make RCP2.6 implausible, necessitating its replacement by RCP3.5. Is this a twisted example of modeling inertia?

  23. 173
  24. 174
    pikkles says:

    Jim,

    I have searched for the paper I read concerning the recent arrival of Castanea dentata in CT (1500 BP in my memory) which you said was false.
    I cannot find it.
    Here is a paper that says it arrived in the hudson valley from its southern refuge, 3600 BP according to this researcher
    http://www.frames.gov/rcs/ttrs/10000/10982.html

    that is significantly different from the paper i read on the subject, i may be remembering wrong, or the findings may simply be different, but it does not particularly take away from my point, which is that current species ranges even late in the Holocene are still in a significantly chaotic state of flux.

    [Response:Wasn't talking about the range or migration of Castanea when I said you were wrong, but rather this last point. Anyway, it's completely irrelevant as I've said. We're all very well aware that ecosystems were massively disrupted and rearranged and reassembled numerous times in the distant past. It's beside the point. We're concerned about system stability NOW. Not going to keep repeating myself on this, have started bore-holing your comments.--Jim]

  25. 175
    Steve Fish says:

    Why Conservatives Turned Against Science.

    An interesting essay by Erik M. Conway and Naomi Oreskes in the Chronicle of Higher Education. As expected with Oreskes, climate science is featured and a few moles have popped up in the comments.
    http://chronicle.com/article/The-Conservative-Turn-Against/135488/?cid=cr&utm_source=cr&utm_medium=en

    Steve

  26. 176
    Chris Korda says:

    pikkles: You don’t seem to be considering the fragility of civilization, or the incalculable human (and non-human) suffering that will result from seriously and rapidly disrupting it. Given the scale and complexity of modern systems even relatively minor disruptions can have hideous impacts, as Sandy demonstrated recently. Of course no one is certain what will happen many millennia from now, but that is totally irrelevant to discussions about forcing from CO2, as others here have attempted to point out to you. The impacts from continued burning of fossil fuel by comparison are well-understood, predictable, and disastrous on a decadal time scale. I suggest you read up on what some of those impacts are likely to be before blithely declaring that “what worries me the most is not so much ecological destruction”, because that “ecological destruction” would very likely eliminate you and your descendents.

  27. 177
    SecularAnimist says:

    FYI:

    Warmer still: Extreme climate predictions appear most accurate, report says
    By Brian Vastag
    The Washington Post
    Thursday, November 8, 2012

    Climate scientists agree the Earth will be hotter by the end of the century, but their simulations don’t agree on how much. Now a study suggests the gloomier predictions may be closer to the mark.

    “Warming is likely to be on the high side of the projections,” said John Fasullo of the National Center for Atmospheric Research in Boulder, Colo., a co-author of the report, which was based on satellite measurements of the atmosphere.

    That means the world could be in for a devastating increase of about eight degrees Fahrenheit by 2100, resulting in drastically higher seas, disappearing coastlines and more severe droughts, floods and other destructive weather.

    Such an increase would substantially overshoot what the world’s leaders have identified as the threshold for triggering catastrophic consequences.

  28. 178
    pikkles says:

    also Jim
    as for my use of the descriptor “very recently”, i think it was pretty clear i was talking about evolutionary history of organisms other than human beings.
    i was addressing the question of how ecologically destructive current warming may become for non-human life.
    of course we are “dependent on both natural and managed ecosystems.” but that does not imply that we are in control of plant and animal migration and ecological change in general.

    [Response:Exactly my point. We're creating instabilities in things we depend on, directly and indirectly.--Jim]

    it is an important to ask the question of how the natural world will fare in a rapidly warming world precisely because we are dependent upon wild ecosystems in many ways, and they are mostly outside of our control.
    i have argued on this thread, if you read my posts, that there are reasons to believe that on the whole, ecological change due to rapid climate change is not at all unprecedented for modern species, and that, with perhaps a little help from us, even rapid warming akin to that of the last glacial termination will not create an apocalyptic global ecological scenario.

    [Response:Nobody's talking about possible apocalypses except you, and most certainly not w.r.t. how fast trees do or do not migrate. Please move on.--Jim]

    similar episodes have happened many, many times before over the course of the Quaternary.

  29. 179
    MARodger says:

    pikkles @166
    Are you really arguing a sensible equivalence here?
    The next glaciation will not be a quick event. Even with an ice age ‘alarmist’ view, it would be hard to see more than a 4ºC drop in global temperatures in the next 20,000 years courtesy of a drop into the next ice age. That means the next millennium of ice age will result in a cooling of 0.2ºC, or the sort of magnitude equal to the rise we can anticipate from the next 10 years of global warming.
    Don’t however take this criticism personally. The link provided @173 shows a similar mush-brained analysis by a crazy Swedish geography professor plus colleagues whose analysis would logically have had every last molecule of CO2 sucked out the atmosphere in just half a millennium.

  30. 180
    pikkles says:

    -
    Jim-
    I dunno what “bore-holing” means. sounds somewhat violent. do whatever you feel is right. feel free to delete all my posts if you feel it is right.
    i am not saying that we should not be worried about the earth as it is NOW.
    that is part of what i’m arguing about.
    I believe that in the situation right now it is a statistical pipe dream that we can realistically think about creating a downward trend in CO2 anywhere in the near future. we are so utterly dependent on fossil fuels, and people in the world who are undereducated and alreadt have far more pressing immediate daily concerns than climate change are not very sympathetic to ideas, however well-meant and sensible they are from our perspective, that require them not to have the things that we in the western world have.
    as such, i am trying to look at the possible good aspects of current warming, since it seems, barring some truly revolutionary innovation we are condemned to it.
    I do not believe that a thoroughly pessimistic view of anthropogenic warming climate is strictly necessary. I’m not sure it’s psychologically healthy or even rational for people to believe that the future is totally apocalyptic if it turns out we cannot manage to bring down CO2 levels.
    That is my personal belief, and I think there is a lot of science behind it. I am aware that it runs somewhat counter to activist sentiments common on this site, but i don’t believe that everyone should live in total abject fear if there is no reason for it.

    apologies, did not hit recapcha

  31. 181
    Chris Korda says:

    I do not believe that a thoroughly pessimistic view of anthropogenic warming climate is strictly necessary.

    No doubt the Koch brothers would agree. I think we should expect to hear plenty more of this BORE-ing argument now that strict denial is untenable. It’s already covered in various FAQs, see e.g. Coby Beck’s What’s Wrong With Warm Weather.

  32. 182
    Ray Ladbury says:

    Pikkles: “as such, i am trying to look at the possible good aspects of current warming, since it seems, barring some truly revolutionary innovation we are condemned to it.”

    Argument from consequences is a logical fallacy. It does not matter whether acknowledging the risks of climate change is good, bad, indifferent, psychologically healthy or liable to cause male pattern baldness. The consequences are what they are. We either accept them as they are or we delude ourselves. Choose one.

  33. 183
    pikkles says:

    Jim
    I have asserted above that a warmer future world will likely be similar to that of the Pliocene with “increased moisture in the atmosphere, increased rainfall, decreased global aridity, and increased warmth”
    As you are probably aware, a potential return to Pliocene global conditions has been a popular recent subject of many studies modeling the probable future of a world warmed by our current and projected levels CO2.

    The Pliocene was a warmer and wetter world. That is well-established enough to call it fact.

    Hence, if the world comes to resemble that of the Pliocene over the next millenium, it will be less arid than present.

    It seems plausuible and likely that there may be episodes of increased aridity between now and a hypothetical stable Pliocene-like future climate.

    But the overall trend would be in the direction of a wetter, likely more widely forested world.

    This does not strike me as very unreasonable, though your sarcasm seemed to imply so, e.g. your comment above in my post 168: “Right, not to mention those ‘facts’”

    [Response:Yeah, well then you should've said what you meant the first time, but at any rate none of this is particularly relevant to anything of importance for near term planning, given how long, and long ago, the Pliocene was. It's just not helpful. It's like you're having an argument amongst yourself--Jim]

  34. 184
    David B. Benson says:

    pikkles — The Borehole will be found listed on the sidebar. Some comments are assigned to it by moderators who have had enough. Read through some of the entries and you will understand.

  35. 185
    mrlee says:

    A thanks to Hank Roberts for keeping it going about Google Scholar. I’ve finally started to use it for my own further enlightenment.

  36. 186
    MARodger says:

    I notice that Roy Spencer has at last removed that silly polynomial-fitted trace from his graph of UAH LT temperature record. His continued use of the polynomial trace probably became a little less than amusing for him last month. (The trace used to be labelled as being for ‘entertainment only’ but this label has been long absent.) Last month he was getting a few comments calling for it to go (Not the first time that has happened.) which prompted Jim Pettit to present a graph that captured the true humour of Spencer’s polynomial graphing. (Spencer’s trace was the 4th order polynomial apparently.)

  37. 187

    http://eh2r.blogspot.ca/ deals with current North Atlantic High pressure blocs. It got some sketches!
    I think its the most interesting new pattern barely discussed.

  38. 188
    Chris Dudley says:

    Chris (#172),

    This newspaper report gives some explanation for the range of model predictions. Apparently CM3 is favored owing to skill in hindcasting relative humidity.

    http://www.washingtonpost.com/national/health-science/warmer-still-extreme-climate-predictions-appear-most-accurate-study-says/2012/11/08/ebd075c6-29c7-11e2-96b6-8e6a7524553f_story.html

  39. 189
    JCH says:

    MARodger says

    I notice that Roy Spencer has at last removed that silly polynomial-fitted trace from his graph of UAH LT temperature record. …

    I noticed also that wood for trees has stopped doing the monthly update for the UAH series.

    2012 -0.089
    2012.08 -0.111
    2012.17 0.112
    2012.25 0.299
    2012.33 0.291
    2012.42 0.369
    2012.5 0.278
    2012.58 0.342
    #Data ends
    #Number of samples: 8″

  40. 190
    SecularAnimist says:

    Joe Romm discusses the NCAR study that I mentioned in comment #177 and Chris Dudley mentioned in comment #188:

    Science Stunner: Observations Support Predictions Of Extreme Warming And Worse Droughts This Century

    The NCAR press release is here:

    Future warming likely to be on high side of climate projections, analysis finds

  41. 191
    Chris Korda says:

    Chris @188, Thanks. The NCAR press release is here. It doesn’t name names though, so I guess CM3′s “skill in hindcasting relative humidity” must come from the Science article “A Less Cloudy Future: The Role of Subtropical Subsidence in Climate Sensitivity”?

  42. 192
    Tsukemono says:

    [edit - submitting comments on the same thread using multiple aliases is not allowed. Do not do it again]

  43. 193
    Chris Dudley says:

    Chris (#191),

    I think I may have inferred too much. Looking at the supplementary material, they are only just getting started with the newer models. They do seem to like CM2.1 so they’ll probably like CM3 better.

    raypierre must be turning cartwheels to see this kind of progress on clouds. Hope he’ll write a review on this paper.

  44. 194
    Harmen says:

    Interesting article on climate change “tail” risk on Bloomberg..

    Hurricane Sandy’s Dangerous Tail
    By Evan Soltas Nov 5, 2012
    http://www.bloomberg.com/news/2012-11-05/hurricane-sandy-s-dangerous-tail.html

    Finally

  45. 195
    Jim Larsen says:

    183 pikkles said, “The Pliocene was a warmer and wetter world. That is well-established enough to call it fact. Hence, if the world comes to resemble that of the Pliocene over the next millenium, it will be less arid than present.”

    I don’t buy the leap. The sun’s brighter. The biosphere is different. And hungry hungry humans exist.

  46. 196
    JCH says:

    It was mostly natural?

    This paper, unpublished, makes a very different claim than Kyle Swanson made in his article here.

    Any comments?

    [Response: it is an interesting exercise in curve fitting, but since it doesn't have any input from forcing data, their projection into the future is just a linear extrapolation + 'noise'. This is not credible. Effectively they are trying to claim that they can derive both climate sensitivity and future levels of CO2 from the linear fit to the past data (which is what the derive as the forced component). Their model for internal variability is new, but it is not magic. - gavin]

  47. 197
    MalcolmT says:

    Jim L @155: You might need to keep an eye on the ‘reviews’ there. At least one AGW denialist has already dissed your book as a load of baloney, starting with the fact that global warming is nonsense.

  48. 198
    Jim Larsen says:

    Pikkles,

    You’re mixing scales. To us, as humans, great grandchildren are the maximum time scale. Beyond that it becomes “posterity”, which we care about in a non-personal fashion.

    So, at age 60ish people have deciding-power and potential great grandchildren. The “personal” issue is thus limited to 80 years or so. There will be issues within the next 80 years, but they’ll be manageable for those with great wealth and power. So, there is absolutely no personal reason for anybody in unelected power to pay the slightest attention to climate change. Elected power is different, of course, so those who are unelectedly powerful have a great personal incentive to warp the electoral process.

    You’re also mixing situations. Using the analogy of a man, a man can get shot and survive. A man can get stabbed and survive. A man can get poisoned and survive. A man can go with insufficient water and food, and yet survive. Do all four, and that man will die.

    Of course, the analogy is for ecosystems and species. Sure, in the past a single dreadful thing happened and ecosystems and species evolved and survived. Then another. Same results. But…. 20 or 30 or 100 dreadful things happen all at once. Are you saying that if an ecosystem can survive a single calamity, it can survive 100 simultaneous calamities?

    Or, are you relying on the mismatch in scale? Yep, chaos and destruction for a MERE 10,000 or 100,000 years…

    And your ice age scenario is dumb as dirt. I’ve read that a SINGLE refrigeration factory would be plenty to prevent any slide into an ice age. Now, if you’re merely using the totally impossible scenario as a way to slide into geoengineering, then I suppose it’s useful in a minor but misleading way.

  49. 199
    Jack Roesler says:

    Here’s a new one. A serial denier of AGW here in Toledo came up with the idea (he found it on the internet) that the increased spin of the Earth’s molten core is the primary cause of the current global warming. That guy just won’t give up.

  50. 200
    Hank Roberts says:

    > he found it on the Internet

    Of course. You can find _anything_ on the Internet.

    It’s like the joke about telephoning the FBI and asking if they have a file on you: the answer is “We do now.”

    You can find some research on the magnitude (very small) of such effects, looking with Scholar.

    If the Toledo guy went to the library and got help from a reference librarian, he’d find out how tiny any such effect is on climate change compared to what else is happening.


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