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Unforced variations: Dec 2012

Filed under: — group @ 1 December 2012

A new meteorological season, perhaps some new science topics to discuss…


369 Responses to “Unforced variations: Dec 2012”

  1. 201
    Superman1 says:

    SecularAnimist #199,

    Please define what you mean by “readily available”.

  2. 202
    Tom Adams says:

    Fly ash from burning coal has some potential to be used for sequestering CO2. Nice if we could use the waste from burning coal to control CO2:

    “The objective of this study is to investigate biogeochemical processes to sequester CO2 and metals
    utilizing metal-rich fly ash. Microbial conversion of CO2 into sparingly soluble carbonate minerals has
    been studied using metal-rich fly ash under different pCO2 and different bicarbonate concentrations.
    Scaling from test tube to fermentation vessels (up to 4-L) using metal-reducing bacteria and metal-rich fly
    ash have proved successful at sequestering carbon dioxide and metals. CO2 sequestration via precipitation
    processes using metal-rich fly ash may complement the capture of carbon dioxide from fossil fuel plants
    while potentially stabilizing fly ash wastes.”

    Not sure where the chemistry thread was heading. CO2 in water produces carbonic acid that can be converted to carbonates. Mother Nature does a lot of this, it’s a big part of the climate cycle. Fly ash is relatively rich in calcium, so it can be use as feed stock for the production of calcium carbonate.

    No new on bottom ash that I can find. But one can release at least some of the metal ions from the stuff, so maybe its possible to make carbonates with that too.

    Mother Nature does not just produce carbonates. She sculps beautiful objects of utility with the stuff. It would be nice if we figured out how to do that.

  3. 203
    Rita says:

    @192 Hank Roberts….

    Thanks for the info on the following link:
    http://www.ipl.org/IPL/Finding?Key=climate+change&collection=gen

    Appreciate your help… :)

  4. 204
    Hank Roberts says:

    > Tom Adams
    Are you quoting from this?
    https://www.netl.doe.gov/publications/proceedings/03/carbon-seq/PDFs/177.pdf

    Bubbling CO2 through hot water with coal ash loaded with nickel and iron, adding agricultural waste, and growing bacteria that thrive anaerobic hot conditions loaded with heavy metals.

    Hey, what could go wrong?

  5. 205
    thingsbreak says:

    Apologies if there’s been a post on this already, but any plans for discussing the PALAEOSENS project and Nature paper? Might be timely considering the latest offal from Matt Ridley and the WSJ.

  6. 206
    Hank Roberts says:

    Oh good grief. You think this stuff is just science fiction:

    (“These algae were designed for the warm, wet, methane-rich conditions of our anaerobic reactors, not the human digestive system!”)

    and along comes <a href="progress

  7. 207
    Hank Roberts says:

    Remember Muller proclaiming “safe fracking”?

    (No, he has no cite on it and no way to know what chemicals are used — there’s always a loophole allowing secrecy about what’s going down the wells.)

    Hey, what could go wrong?

    Here’s a clue: http://www.propublica.org/article/trillion-gallon-loophole-lax-rules-for-drillers-that-inject-pollutants

    Great chance to dump toxics and get paid for the waste instead of paying to treat it safely. Just pump it into the fracking wells.

    Crap.

    “What do you think of intelligent life on Earth?”
    “It would be a good idea.”

  8. 208
    Tom Adams says:

    #204 Hank. A number of heavy metals are key to life. Iron transports your oxygen, for instance. So take a breath and think about it. Heavy metal carbonates are big players in the natural carbon cycle. So, it’s not necessarily all that scary. Technophobes are scary, they may be worse than deniers as a practical matter.

  9. 209
    Esop says:

    Prediction:
    When the world (likely) does not end on December 21st, we will see Op-eds in rags like Wall Street Journal use that as proof that climate science is also wrong.

  10. 210
    Tom Adams says:

    #204 Hank, a seashell is a heavy metal carbonate formed by a biological process that is important in the natural carbon cycle. Heavy metal is a pretty inexact term. It does not always mean toxic metal.

  11. 211
    simon abingdon says:

    @Rita Umile
    Rita, has anyone ever told you what E=mc2 means? Everyone should know this, so let me explain: c is the speed of light, a extraordinarily large number, c2 is c multiplied by itself, an extraordinarily large number muliplied by the same extraordinarily large number; believe me, an unimaginably large number. So the equation E=mc2 says that tiny amounts of matter (m) can be converted (if we have the technology and with suitable materials we do) into unimaginably vast amounts of clean (no CO2!) energy (E). Good idea, huh?

  12. 212
    David B. Benson says:

    Doug @200 — Nowhere in the upper Rio Grande valley is going to run short of well water. However, I’ve lived in Albuquerque back in its pre-smog days; wasn’t so good even then. There are much nicer locations further north but I suppose with fewer employment prospects.

  13. 213
    perwis says:

    MARodger @198

    My argument is as follows:

    1. Model uncertainty are dominant in climate model predictions for time horizons of at least two decades (see Hawkins & Sutton 2009, especially Figure 2 & Figure 4). This uncertainty is much due to the inertia of the climate system. Stott & Kettleborough (2002) puts it like this: “Until 2040, uncertainty is dominated not by uncertainties in emissions scenarios but by uncertainties in climate response.” (p 725)

    2. If this relationship of a lag between emissions and model predictions hold 20 years from now, then it follows that global emissions until year 2030 will essentially determine global warming in 2050-2060s (not counting short-lived aerosols).

    3. The present trend of global emissions of CO2 track the highest SRES-scenarios (see the graph here: http://www.columbia.edu/~mhs119/)

    4. It is not unlikely that this trend will continue until 2030, given the lag in the energy system, the present lack of international agreement and political will and because developing countries cannot be expected to slow emissions growth during this time period (see e.g., Anderson & Bows 2011)

    5. Hence, high-end studies for the mid-century are relevant, even if we belive that it is unlikely that the world will be on a A1FI or RCP8.5 pathway after 2030.

    Does this hold?

    Regarding 1&2. Perhaps the climate inertia is not so great, if we have higher growth in emissions? Then this relationship might look different in 20 years from now?

    Regarding 3. I noticed that Sato & Hansen’s updated graph on historical greehouse gas forcings is substantially below the highest SRES-scenarios. So, I guess it is not as bad as it looks from just looking at CO2-emissions (at least for the short-term).

    Regarding 4. Well, this is anyones guess. But the points Anderson & Bows makes on the differences between emissions in rich and developing countries is important and needs to be taken into consideration even by “optimists”.

    My point is simply this. “Business as Usual” growth in emissions is difficult to deviate from substantially in a 20 year time frame (due to the ineratia in the energy system), and we cannot write off the possibility of +4 degrees (due to uncertainties and the inertia of the climate system).

    References

    Anderson, K., & Bows, A. (2011). Beyond “dangerous” climate change: emission scenarios for a new world. Philosophical transactions. Series A, Mathematical, physical, and engineering sciences, 369(1934), 20–44. doi:10.1098/rsta.2010.0290

    Hawkins, E., & Sutton, R. (2009). The Potential to Narrow Uncertainty in Regional Climate Predictions. Bulletin of the American Meteorological Society, 90(8), 1095–1107. doi:10.1175/2009BAMS2607.1

    Stott, P. a, & Kettleborough, J. a. (2002). Origins and estimates of uncertainty in predictions of twenty-first century temperature rise. Nature, 416(6882), 723–6. doi:10.1038/416723a

  14. 214
    sidd says:

    in cryosphere discuss
    http://www.the-cryosphere-discuss.net/6/5225/2012/tcd-6-5225-2012.pdf
    Goeller et al. discuss a model for subglacial hydrology, show how allowing for a basal water layer can increase mass waste. Nice treatment.

    sidd

  15. 215
    Hank Roberts says:

    Compare the metals found in coal ash (you know how to look this stuff up) to the minerals (mostly calcium) in seashells.

    Look at the solubility of lead carbonate, for example.

    Just think this stuff through, and remember there are optimists out there eager to say it’s not a toxic waste, it’s a salable product, if you just see things their way. Good luck.

  16. 216
    Ray Ladbury says:

    @211 Simon manages to be condescending, impertinent and irrelevant in just six lines! Oh, and Simon, if you are standing at ground zero of a nuclear blast, E=mc^2 would suddenly seem like a very bad idea. Context is everything.

  17. 217
    Superman1 says:

    I agree with Ray’s comment in #216. But, energy use and availability is only one of many considerations. We need to think in terms of resource limitations, only one of which is energy. A report in Climate Progress shows how we have overshot the Earth’s biocapacity, and the gap is growing (http://thinkprogress.org/climate/2012/12/15/1329841/report-humanity-has-overshot-the-earths-biocapacity/). So, those on this blog who keep playing the one-note symphony of replace fossil fuel with renewables need to think beyond one-dimension. We are the only species on this Earth who have gone beyond the resource footprint we had when we first appeared in our present form, and there is no reason to believe this massive increase in resource utilization could be sustainable.

  18. 218
    Rita says:

    @Simon and et al….

    I am here to learn, and I have a tortoise shell regarding self esteem (I am TOUGH)…so Hakuna Matata (no worries, guys/gals), throw it MY way!!!

    As I cannot at this time dedicate myself only to this subject, it will take me a while to get up to speed…I will catch up though…because this issue matters to me, and if I’m going to talk to others on climate, I better be able to speak intelligently on the subject, right?

    @Simon, et al, if you’d like to help me “catch up,” feel free to email me material…you may use UMILERITAC@aol.com….

    Again…I am tough…I wear teflon…and it is all about the knowledge…I want to learn about this…

    SO, I hope that everyone here realizes that it is a GOOD thing that people like me are starting to care….

  19. 219
    Rita says:

    @Simon…Additionally…it s/b HAZAAH!!–whenever someone wants to learn…right?

  20. 220
    Tom Adams says:

    #215 Hank. Compare the metals found in dirt (you know how to look this stuff up) to the minerals (mostly calcium) in seashells.

    Look at the solubility of lead carbonate, for example.

    Just think this stuff through, and remember there are optimists out there eager to say it’s not a toxic waste, it’s a salable product, if you just see things their way. Good luck.

  21. 221
    Susan Anderson says:

    Rita Umile et al.

    Simon Abingdon has yet to make a substantive comment based on accurate science here, though e=mc2 is a nice cheap shot enabler for him here. He is fond of sending little darts, particularly at women and at those who admit they don’t know everything. Perhaps he thinks he does know everything, but it seems his purpose is to undermine, destroying being always easier than building.

    It is if anything an honor to be targeted by him and other fake skeptics. But why do they bother?

    Returning to Rita, I enjoyed your comments and hope you will continue to grace RC with your comments, though I like you am only a guest.

  22. 222
    MARodger says:

    perwis @213.

    Regarding your points 1 & 2.
    The figure 4 of Hawkins & Sutton 2009 that you reference cetainly supports your position. Myself, I am not entirely happy with such a position.

    You do mention (while I would emphasis) that there are two parts to this 20 year lag in response. Firstly our emissions don’t immediately cause warming. And secondly I would emphasis that our ability to stop emitting requires decades – our ability to reduce our emissions is heavily constrained at a global level.
    Yet this lag is not that much of a damper on the system.

    The difference between A1FI and the next worst scenario, A2, is quite large after 2030 very roughly amounting to some 140GtC emissions or 70ppmCO2 by 2060.
    How much this would impact temperature in 2060 depends on the Climate Response Function. According to Hansen et al 2011 Earth’s Energy Imbalance and Implications (see figs 7 to 10), the CRF achieves about 40% of the equilibrium warming in about 5 years. I see no mention that this is affected by differing ECS (although Hansen et al 2011 argue ECS=3ºC (+/- 0.5ºC) for all fast feedbacks).
    That said, with the high ECS required to bring a 4ºC rise by 2060, the A2-A1FI difference would (40% of say 60ppmCO2?) be very roughly 0.35-0.5ºC. Thus the difference between A1FI & A2 by 2060 is not nothing. Note also fig 2 in your reference Stott & Kettleborough 2002 for 2050-60. It is showing a best guess temperature of something like 1.8ºC for A2 & 2.1ºC for A1FI.
    I would also suggest another possible mechanism that may play out if ECS is so high. If ECS is 4ºC+ to give a 4ºC rise by 2060, would not the urgency of climate change be obvious even from Wattsupia by 2020 allowing policy to reduce global emissions to A2 and below by 2030?

    Regarding point 3.
    The CO2 emissions are on a high track. It is CFCs & CH4 that have tempered recent rates of GHG forcing. But it is usually said that in the long term it is CO2 we have to worry about.

    All in all then, I would still argue that A2 would not cause a 4ºC rise by the 2060s without an exceptionally high ECS or very strong long-term feedbacks. Such a rise thus would require A1FI/RCP8.5 emissions. (The RCPs don’t appear to have an A2 equivilant and of course this is all splitting hairs – A2 with best-guess ECS will still top a 4ºC around 2100 according to IPCC AR4.)

  23. 223
    Steve Fish says:

    Re- Comment by Superman1 — 20 Dec 2012 @ 7:35 AM

    Your condescending statement that posters here- “keep playing the one-note symphony of replace fossil fuel with renewables need to think beyond one-dimension,” is offensive. You have no idea how we think. Steve

  24. 224
    SecularAnimist says:

    Superman1 wrote: “So, those on this blog who keep playing the one-note symphony of replace fossil fuel with renewables need to think beyond one-dimension.”

    This is a climate science blog. As the moderators have repeatedly and gently reminded us, discussions of technology and policy solutions to the problem of GHG emissions are off topic (though they tolerate them to some degree, probably because they realize that looking for solutions is a natural, and positive, reaction to recognizing the scientific reality of the problem).

    That being the case, discussions of humanity’s myriad OTHER “resource” problems which are unrelated to climate are certainly off topic for this blog, and most commenters respect that. It doesn’t mean that we are not thinking about those problems.

  25. 225
    Hank Roberts says:

    is 220 a quote-bot? Text is exact copy of the words I posted in 215, repeated under a different userid

    If it’s actually posted by Tom Adams, please don’t be intentionally confusing. There’s ample literature on coal ash and EPA has a large docket on the rulemaking:

    https://www.google.com/search?q=EPA+coal+ash+combustion

  26. 226
    Hank Roberts says:

    Kurzweil on KQED Forum: solar is doubling every two years — seven doublings until it suffices for all our energy needs — and it’s using semiconductor/nanotech material, so is not atypical in this growth rate.

  27. 227
    Hank Roberts says:

    NPR right now has a story on
    The National Intelligence Council’s Global Trends 2030 report
    http://m.npr.org/news/front/166895624?start=10
    TRANSCRIPT is at that link, page down a few to get to it.
    ROBERT SIEGEL, HOST

    Big surprise in that is calling climate change unexpectedly fast and beyond the ability of scientists to predict, “black swan” stuff

  28. 228
    Tom Adams says:

    #215 Hank. You don’t think coal ash is a salable product?

    I have this trick question that sometimes even stumps engineers: What’s a cinder block made of?

    Answer: Cinders.

  29. 229
    Rita says:

    Anyone have thoughts on retiring Senator Jeff Bingaman’s philosophy?

    Would implementing a cap-and-trade program for the power sector be at least a step in the right direction?

    I believe that California is currently in the process of implementing a new cap-and-trade program to this effect, and many are optimistic that this new program will be successful and set a precedent for the rest of the country.

    Research by the Brookings institute indicates that a price on carbon for the power sector does not produce offsetting increases in emissions in other sectors. Rather, carbon emissions outside the power sector would actually fall slightly relative to baseline because of economic linkages between sectors and consequences of higher electricity prices on overall economic activity.

    Brookings Institute modeling also indicates that limiting carbon pricing to the power-sector would have little negative effect on employment (less than 1%). It would reduce investment in the capital-intensive energy sector, which would, in turn, lower import of durable goods and strengthen the United States in terms of trade.

    Of course, limiting carbon pricing to the power sector won’t produce as much revenue as economy-wide pricing, but it is movement in the right direction…..Correct?

    (fire away)
    http://www.brookings.edu/research/papers/2012/10/05-pricing-carbon-morris

  30. 230
    Hank Roberts says:

    Tom Adams, you haven’t read the cites I gave. You’re misstating my comment. I’m not interested in strawman stuff. I’m done replying to you on this subject.

  31. 231
    Superman1 says:

    Pete Best #35,

    “Can’t avoid 2C really and a 1 in 5 chance of reaching 4C…..Sea level rise is vastly underestimated and methane plumes all added into the mix…..Personally I would suggest its time to know that several recent studies from the world bank, PwC and IEA all reported the same thing, namely that we are heading for the cliff…..The other more interesting article is the one about the 1200 power stations being built mainly in China and India….Of course the only possible explanation for the powers that be ignoring the facts of science is the idea of it all being only a probability and hence the cynics and deniers still hold sway.”

    Something is not adding up right. The climate outlook ranges from grim to catastrophic. But, there’s one key player(s) that seems to be missing. The defense/intel/DHS world has the job of protecting national security. I find it hard to imagine a more critical problem than survival of the citizenry past mid-century. Yet, where are they?

    They are reading the same climate papers that I am, and probably far more. The conclusions are not that hard to extract. We have basically reached the atmosphere’s capacity for CO2 before irreparable damage is done. Some people believe we have reached that point already. Only the most extreme measures can give us any chance of survival (termination of all fossil fuel use ASAP, reforestation as rapidly as possible, some level of geoengineering to ‘quench’ the self-sustaining mechanisms that have already made their appearance), yet absolutely nothing is being done.

    What are these agencies doing with the data and analysis? Are they setting us up for a climate change Pearl Harbor? Something even more sinister? I find their absence from the table beyond belief, and very much out of character with how they approached problems of far less significance when I was dealing with them.

    Pete, I don’t buy your statement that “the cynics and deniers still hold sway”. When these groups close the heavy doors and close the electronic locks, the hard science and technology issues get thrown in front of all participants. I suspect the Inhofes and Bartons of this world dispense with the denier facade they use to attract the ‘rubes’ in their electorate, and see the hard reality of where we’re going. I just find it hard to imagine these groups that operate in the shadows issuing an intel report periodically, and letting it go at that.

  32. 232
    flxible says:

    Tom Adams @ 227
    Cinder blocks are made of cast concrete, regardless of what material [sand for high density blocks, various industrial waste for low density] is used as filler or aggregate.

  33. 233
    Eric Rowland says:

    @228, both cap and trade and a carbon tax can be effective tools for moving away from carbon based emissions. Both are likely superior models to the largely command and control based deployment we see today in the US. That said, a local or regional cap and trade program or carbon tax carries with it the possibility that it may drive business to move its emissions to a non regulated location.

    Since there is a direct correlation between the carbon content of a fuel and that fuel’s emissions, a carbon tax based on carbon content would be easiest to impliment. But the proceeds from a tax must be directed at subsidizing the implimentation of additional renewable energy resources to be effective. Cap and trade is more complex but is a more direct market instrument. As you noted, it’s likely a step in the right direction.

  34. 234
    Chris Korda says:

    MARodger @ 222: This seems an opportune moment to repost links to the RCP temperature projections Chris Dudley, Patrick, Troy et al. helped me calculate a couple of months ago. No sense wasting all that hard work. For better or worse the results seem to be very much in agreement with the leaked bits of AR5 I’ve gotten around to reading.

    The abbreviated version: The US EIA’s IEO2011 Reference case projects “1 trillion metric tons of additional cumulative energy-related carbon dioxide emissions between 2009 and 2035″. This was demonstrated to be equivalent to following RCP8.5 until 2035. Combined with revelations about the long-term nature of energy infrastructure investment, this demonstration led Jon Kirwan[1], me, and others here to opine that 8.5 constitutes a reasonable approximation of reality for the next couple of decades, i.e. it represents what fossil fuel companies and equivalent state actors are actually planning to do, in contrast to governmental rhetoric delivered at international conferences, however passionate and well-intentioned. The increase in average global surface temperature likely to result from following RCP8.5 is shown by the red and green lines in this chart. The differences result from choice of Climate Response Function[2], but according to Hansen et al.’s 2011 Earth’s energy imbalance and implications the red line is more likely, and my reading of more recent sources including AR5 has tended to confirm that.

    [1] “… I will use RCP8.5 as the ONLY scenario I use for thinking purposes until AFTER I see serious political action AND YEARS AFTER I see significant implementation already taking place. Until then, RCP8.5 is reality.” Jon Kirwan, Oct. open thread, #269
    [2] The gory details are described here: Computing temperature change for RCP scenarios.

  35. 235
    wili says:

    Thanks for putting it all together like this, Chris. But looking at your linked graph, it seems to me that the red line has already been falsified, as it shows us going past one degree C above preindustrial levels by now, even though last I checked we were still a bit below that. Is this just temporary masking from aerosols from dirty Chinese coal plants? (Plants that, from what I’ve heard, the Chinese are hurrying to clean up.) Or am I missing something.

    In any case, the red line is not a very happy one for the near future–two degrees by 2040, three by 2070, four by the end of the century, and over seven the century after that!

  36. 236

    “But the proceeds from a tax must be directed at subsidizing the implimentation of additional renewable energy resources to be effective.”

    The experience of British Columbia suggests otherwise; their carbon tax is ‘revenue neutral’–actually, in practice, very slightly revenue-negative–as the revenue raised is rebated via the income tax system. (This is pretty close to what Dr. Hansen advocates, IIRC, and Dr. Andrew Weaver has written favorably about it.)

    Since implementation of the tax, per capita emissions have fallen faster than in other jurisdictions, even as the BC economy has performed better. The reason that this can work is that the tax acts as a price signal in the marketplace, and therefore creates incentives toward greener choices.

    Of course, “correlation does not equal causation,” so the results so far are not ‘proof,’ but rather indications that this theoretically sound model may actually work in practice. Still, it’s nice to have that much.

    http://daily.sightline.org/2012/11/05/deciphering-the-impacts-of-bcs-carbon-tax/

  37. 237
    Tom Adams says:

    225 Hank. Fly ash is currently unregulated by the EPA.

  38. 238
    SecularAnimist says:

    Eric Rowland wrote: “both cap and trade and a carbon tax … are likely superior models to the largely command and control based deployment we see today in the US.”

    What “command and control based deployment” of what?

  39. 239
    Hank Roberts says:

    > currently unregulated

    The industry got an exemption long ago, and went on ignoring public health risks. The harm has become undeniable. Yes, that’s how the USA works. No, it hasn’t proved to be a wise approach.

    http://pubs.acs.org/doi/abs/10.1021/es301467q
    http://www.epa.gov/wastes/nonhaz/industrial/special/fossil/ccr-rule/index.htm
    http://www.statejournal.com/story/16546862/groups-to-sue-epa-for-release-of-coal-ash-regulations

    Don’t fall for the PR, and don’t spin without citing sources. It’s not credible.

  40. 240
    Rita says:

    @ Eric Rowland, Kevin McKinney & SecularAnimist (greetings!)

    Okay,

    Still I’m still learning here…

    I’m ASSUMING that Command and Control refers to the use of direct regulation as a policy instrument to achieve emissions reductions throughout a geographic area and within a very specific (short) time period (and w/o damage to the policy objective). Is this even being DONE right now in the USA? Sorry for my ignorance…

    REGARDLESS…can such a brusque approach really work? Sounds a bit like “a bull in the China Shoppe.”

    Command and Control (imo) has serious negative consequences such as an increase in the costs of emissions reductions…leading to negative economic implications for businesses and society as a whole (let’s remember the 99%).

    Alternatively, cap-and-trade has already proven its effectiveness in the USA through the acid rain program, where it quickly and effectively reduced pollution levels at a far lower cost than expected. A good thing, right?

    And, E.U.E.T.S. has shown that cap-and-trade can be extended to carbon, in consensus among many countries, and resulting in a price on carbon that drives emissions reductions. Success here being that reductions in pollution that industry feared would be excessively costly were instead achieved at a fraction of the original estimates.

    AGREED: “the proceeds from a tax must be directed at subsidizing the implementation of additional renewable energy resources to be effective.” IMO, that is the ENTIRE point of the TAX….:)

    Thanks for letting me participate here…and HAPPY HOLIDAYS….

    I will try to approach my posts from a science perspective in the New Year….

  41. 241
    Superman1 says:

    Wili #235,

    “In any case, the red line is not a very happy one for the near future–two degrees by 2040, three by 2070, four by the end of the century, and over seven the century after that!”

    I’m less comfortable than you are in interpreting these models, given their assumptions. For example, consider the Rowlands model, where we debated the issue of its temperature prediction in ~2050, 3 C or 4 C. From the Abstract in Rowlands et al paper: “We find that model versions that reproduce observed surface temperature changes over the past 50 years show global-mean temperature increases of 1.4-3 K by 2050, relative to 1961-1990, under a mid-range forcing scenario.” In the full paper, they state: “Towards the end of the century, we observe a similar relationship with the IPCC expert estimate, although by that time the uncertainty could be larger if carbon-cycle feedbacks were included in our ensemble”. So, they are using a model that excludes carbon-cycle feedbacks, gives good agreement with the past when there were little carbon-cycle feedbacks, and attempts to estimate the future with similar physics when there could be massive carbon-cycle feedbacks.

    What does one do with such a model; what is the value of it or other similarly-based models? How much better is it than a back-of-the-envelope estimate? Yes, it provides a conservative lower bound estimate, and with the feedbacks added in, the actual numbers will be worse. But, how much worse? What serious decision-making could such models impact or inform?

    It seems to me there are three main questions one would want climate science modelers, theoreticians, and experimentalists to answer:
    1) For a given temperature increase, what is the pattern of frequency and magnitude increases for what were once considered ‘extreme’ events (re Hansen’s paper);
    2) For a given temperature increase, what known positive feedbacks can be accelerated and new positive feedbacks triggered such that self-sustaining temperature increases can occur.
    3) At what point in time can we expect the temperature increases in 1) and 2) to occur?

    Issues 2) and 3) reflect the real danger points, and models that do not include at least all known positive (and negative) feedback mechanisms are not only of very limited utility, but could be very misleading for policy purposes, due to attenuation of the urgency. My own experience with fluid modeling, admittedly in a different velocity range, was that physical and chemical phenomena that were known to be important would never be excluded from serious models used to inform decision-making. Even if these phenomena were ‘soft’, we would include them and account for the softness in error estimates. I personally cannot believe that the ‘black’ world is not doing exactly that, in order to gain a somewhat better perspective on what really awaits us for climate change in this century.

  42. 242
    MARodger says:

    Chris Korda @234

    Your graph of emissions to 2400AD certainly shows RCP8.5 as the big daddy of emissions projections, dwarfing all others. I note A1FI isn’t marked which by my measurements is even more of a beast and perhaps there is no A2 equivalent in the RCPs because RCP8.5 represents a A1FI/A2 hybrid.

  43. 243
    Tom Adams says:

    239 Hank. Uncle!

  44. 244
    Chris Korda says:

    wili @235: Falsified is a strong word. Yes, the green line is better at reconstructing historical data, but that doesn’t mean the red line won’t be better at predicting (or deconstructing?) the future. The referenced Hansen paper only applies Climate Response Functions to historical data, and they get more plausible results, but their math is also considerably more complicated than the stripped-down version I used. I expect to see more definitive answers soon, because Hansen et al. are allegedly preparing a new paper that applies Climate Response Functions to projected emissions: “In a future paper when we replot Figure 16 in conjunction with our simulations for the future we can use the new RCP scenarios…” AC C12485: ‘Referee #2 – Responses’, James Hansen, 29 Nov 2011

  45. 245
    Chris Korda says:

    MARodger @242: Just to clarify, the graph is from an IPCC 2010 pre-release AR5 document by Gian-Kasper Plattner & Thomas Stocker (University of Bern): From AR4 to AR5: new Scenarios in the IPCC Process, p. 11. I merely annotated it. You can find a similar graph that projects to 2500AD on the very last page of the “official” AR5 charts, though there are some minor differences.

  46. 246
    Hank Roberts says:

    Tom: Nephew! (-:
    we’re just not cynical enough yet, but working on it.

  47. 247
    perwis says:

    MARodger @242

    1. The RCP:s are chosen so to “span” the “scenario-space” (published literature).

    Moss et al (2010) explains: “The selected set of RCPs spans the range of radiative forcing scenarios in the published literature at September 2007. For energy and industry CO2 emissions, RCP8.5 represents the 90th percentile of the reference emissions range, while RCP2.6 represents pathways below the 10th percentile of mitigation scenarios. They are also similarly representative of emissions of greenhouse gases and particles other than CO2″

    2. RCP8.5 is based on an updated A2-scenario.

    Rihai et al (2011) explains the lineage:
    “The RCP8.5 is based on the A2r scenario (Riahi et al. 2007), which provides an updated and revised quantification of the original IPCC A2 SRES scenario storyline (Nakicenovic et al. 2000). With a few exceptions, including an updated base year calibration (to 2005) and a revised representation of short-term energy trends, especially in developing countries, the RCP8.5 builds thus upon the socio-economic and demographic background, resource assumptions and technological base of the A2r scenario.7″

    3. There is a special number of Climatic Change devoted to the new scenarios, 2011 vol 109: http://link.springer.com/article/10.1007%2Fs10584-011-0157-y

    Moss, R. H., Edmonds, J. a, Hibbard, K. a, Manning, M. R., Rose, S. K., van Vuuren, D. P., Carter, T. R., et al. (2010). The next generation of scenarios for climate change research and assessment. Nature, 463(7282), 747–56. doi:10.1038/nature08823

    Riahi, K., Rao, S., Krey, V., Cho, C., Chirkov, V., Fischer, G., Kindermann, G., et al. (2011). RCP 8.5—A scenario of comparatively high greenhouse gas emissions. Climatic Change, 109(1-2), 33–57. doi:10.1007/s10584-011-0149-y

  48. 248
    Patrick 027 says:

    Re 238 SecularAnimist (re 233 Eric Rowland), re 240 Rita, re 236 Kevin McKinney –

    An example of command and control might be fuel economy standards. Also, the (partial? as I have been under the impression there are some conditions in which fluorescents shouldn’t be deployed, and … ?) phasing out of incandescent light bulbs. (If those who argue against these options were more enthusiastic about the price-signal mechanisms, I’d take them more seriously. Still, even with a proper tax rate on climate-changing and ocean-acidifying pollution, I’d argue keeping or adding some such auxiliary policies would be good (although they needn’t necessarily be command and control; they could be incentives like rebates for efficiency in buildings and appliances, etc.), in part because real markets aren’t ideal, and there’re learning curves. Production possibilities curves can be concave in parts; etc. In other words, for at least some period of time, it makes sense to me to offer additional incentives for some things. Some people may need to get used to some things, like having solar roofs in the neighborhood, etc. http://www.scientificamerican.com/article.cfm?id=solar-panel-boom-pits-neighbor )

    IMO A formal justification for the tax is the externality. Aspects of this particular externality make it tricky to allocate revenue as such (where should we build the aquaducts and where do we put (invest) the money until we need it; how do we compensate for economic/other injury without encouraging maladaptive behavior (not meant to imply it can’t be done; it certainly can)), so putting it anywhere helpful (with reasonable cost-effectiveness) may be justified (if a cut in other taxes helps the economy then there will be easier to get back tax revenue later to pay climate change-related costs, so that could be an investment) (include international spending as an option – like contributing to paying for clean energy infrastructure in developing countries). Consider the long lives of solar panels, that option makes sense. Learning curves and mass-market advantage are reasons for subsidizing promising fledgling industries; Government R&D in general has additional justification besides AGW/OA (OA=ocean acidification – as used @ skepticalscience).

    (typed fast, pardon grammar and style)

    re 209 Esop – remember to point out that the Mayans were not wrong. Indeed, this day, which was on the calendar, has arrived. Time keeps going at 1 second per second. :) http://www.slate.com/blogs/bad_astronomy/2012/12/18/maya_apocalypse_2012_doomsday_end_of_the_world_prophecies_are_nonsense.html

  49. 249
    Patrick 027 says:

    Clarifications:
    1. people are not perfectly rational.
    2. as the same forcing that can sustain an ice age might not be enough to start one, the same incentives that would sustain sustainable behavior might not be enough to get there. For individuals sometimes; also sometimes there’s institutional/social stuff – the way people do things – it may be hard for an individual to change when others keep going the same way, and there’s that whole learning curve issue; also supporting infrastructure or planning (HVDC grid stuff). The aesthetics of solar roofs perhaps depends on their presence (frequency-dependent selection) – not to say that that’s all the Scientific American article was about – glare is an issue, apparently (I would think only for certain times of the day for any given geometry (PS I used to live where I couldn’t look out one particular window at a particular time of day for some part of the year (don’t remember which part) in sunny weather because of a neighbor’s (assumed) skylight – didn’t begrudge my neighbor for having a skylight as they make a lot of sense); being on rooftops – certainly I would think glare off of side-facing windows or ground-level pools or shiny cars or wet roads (or even some dry roads when driving west at sunset) would be more common… on the other hand size is a factor…) … another issue is prejudice (e.g. Hindenburg and hydrogen, cast-iron vs steel lawn mower blades); people need to learn to distinguish between solar cell A and solar B if there were an issue with one and not the other)
    3. also, there could be non-AGW/OA related justification for phasing out incandescent light bulbs – it may just good for the economy – but generally IMO the government shouldn’t be constantly trying to optimize the private sector; in this case there is a particular compelling issue… etc.

    Okay, done OT rambling.

  50. 250
    Patrick 027 says:

    … I heard on the Weather Channel yesterday that much of Madison WI’s snow accumulation occured during above freezing temperatures. Of course this is possible. But how often does that happen?


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