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  1. Two comments/questions

    “The curve of temperature as a function of time over the 20th century has three parts: a steep rise in the beginning, a flat middle part commonly attributed to aerosols, and a very steep upswing at the end.”

    Q: What is the difference between “steep” and “very steep” in your statement ?

    Second question that I already asked Stefan in the previous post on the subject (sorry, I just discovered the whole topics at this occasion ! ) : do you agree that if there is a very long relaxation time, so that the proportionality of the derivative of sea level to the temperature anomaly is a good approximation , then a sea level rise of around 10 meters throughout the next millenium is already unavoidable whatever we do now, since it is very unlikely that we can contain the warming below 2°C ? ( at zeroth order the rate will continue at least at 3mm*2°C/0.7°C = 1 cm/yr throughout 1000 years in any case)

    Comment by Gilles — 6 Apr 2010 @ 10:24 AM

  2. Martin,

    Great post. Its encouraging to see an example of (relative) amateurs and climatologists collaborating together over the internet on a paper. I’m hopefully embarking on something similar myself with remote sensing urbanity proxies and UHI in the near future.

    The interdisciplinary nature of climate science really helps in making it possible for folks with different specializations (say, statistical analysis, remote sensing or programming) to work with scientists on projects like these. Tamino’s collaboration with James/Gavin/Mike et al and Nick Barnes and the CCC project are other good examples.

    Comment by Zeke Hausfather — 6 Apr 2010 @ 10:50 AM

  3. Martin and Stefan:

    Fascinating and convincing.

    Setting aside your robust projections, the case for warming, to date, is absolutely stunning!

    Comment by Len Ornstein — 6 Apr 2010 @ 11:00 AM

  4. Nice! I second the recommendation of Jaynes 2003, it is very though provoking.

    Comment by Dikran Marsupial — 6 Apr 2010 @ 11:22 AM

  5. ” approach to statistics that is easily misunderstood and often misused. Statistical refutations of “silly null” hypotheses abound — like the silly null of no relationship between temperature and sea level rise. If this sounds all cryptic to you, I don’t blame you.”
    Exactly to a high power. Statistics is one of the hardest subjects there is. Don’t expect most people to get anything right in statistics. But everybody should be taught more statistics, starting in the 3rd grade. See: “Probability” by Jeanne Bendix, a book for 8 year olds.

    Comment by Edward Greisch — 6 Apr 2010 @ 11:27 AM

  6. Thanks for this fascinating article. I really enjoyed following how your ideas developed: “Science in the making!”

    PS: On my web browser the paragraph beneath the first graph overlaps with the graph and its description.

    Comment by Martin2 — 6 Apr 2010 @ 11:34 AM

  7. “Q: What is the difference between “steep” and “very steep” in your statement ?”

    I would assume “steep” is a rise that is significant and “very steep” is a rise significantly higher.

    Comment by Completely Fed Up — 6 Apr 2010 @ 11:48 AM

  8. Thanks for that article. The historical narrative behind scientific work is impossible to glean from formal publications. The scientists themselves are well aware of the back story because they live it and exchange stories at conferences and, yes, through emails. Science is not some linear process of deduction by Spock-like figures but a more erratic process of discovery and setbacks by humans; stories like this one need to be told more often.

    The article shows that, while it is possible for an outsider to make a real contribution to climate science, the biggest barrier to entry is not institutional resistance to new ideas but the difficulty of mastering a new subject.

    Also, the fact that the paper was rejected by Nature, even though Stefan Rahmstorf was a co-author, shows that the allegation that scientific publishing is a conspiracy, where the big names get their papers easily nodded through by their cronies while the little guys are the only ones to be rejected, is quite false. Of course this is obvious to any experienced researcher but not so much to outsiders.

    [Response: I’ve certainly had more papers rejected than accepted by Nature and Science. And my first two tries got accepted, in 1994 and 1995, although I was single author and completely unknown at the time, with a recent PhD from the quiet scientific backwater New Zealand (sorry friends down under!) and no publication record to speak of. Peer review is not perfect, but it does work to first-order approximation by scientific merit. -stefan]

    Comment by Andy S — 6 Apr 2010 @ 12:27 PM

  9. Excellent narrative, thank you.

    I was waiting in suspense to see if the reservoir computation by Chao would come into play, and bingo there it was.

    Comment by Doug Bostrom — 6 Apr 2010 @ 12:40 PM

  10. The closeness of fit is amazing, I don’t think I had looked closely at the paper. I wonder does it matter that the (semi-empirical fit) blue curve diverges from the pre-1880 data (red curve)?
    I mean in terms of using the obtained relationship to predict future sea level.

    There are two articles in Nature Reports: Lowe/Rahmstorf. While Jason Lowe argues the Rahmstorf/Vermeer approach needs to be set against physical plausibility (eg the Pfeiffer et al paper) is it fair to say you don’t disagree fundamentally? Both seem to say in the end that AR4 was too low because it ignored some poorly defined contributions, SLR of 1-2m by 2100 is possible, but >2m is very unlikely.

    (clearly there is still some difference of opinion over whether somewhat under 1m or somewhat over 1m is most likely)

    [Response: That’s correct – these are respected colleagues and we don’t disagree fundamentally, we just disagree by degrees. And scientists should disagree in this constructive way! Where there’s uncertainty, we debate the strengths and weaknesses of different approaches, we discuss physical plausibility and other issues, people can have different views on those things and that is how science advances. This is the healthy normality of science, it is also why science is so much fun, and the Sunday Times article by Jonathan Leake in January (which I think prompted Nature to invite our commentaries) was complete bogus in claiming that “Climate change experts clash over sea-rise ‘apocalypse’”. But in the meantime we’ve seen more examples of Leake’s special relationship with the truth. -stefan]

    Comment by simon evans — 6 Apr 2010 @ 12:49 PM

  11. Can you comment on this, which is to be published soon.
    http://www.jamstec.go.jp/frsgc/research/d2/masayo.ogi/2009GL042356-pip.pdf

    [Response: I’ve not read the paper except a quick read through, but I’d say no surprise: “Anticyclonic wind anomalies over the Beaufort Sea during summer favor low September SIE and have contributed to the record-low values in recent summers, perhaps by enhancing the flux of ice toward Fram Strait in the trans-polar drift.” Many scientists have been working on this issue — to what extent was 2007 a freak ‘wind anomaly’ and to what extent is that part of the long term trend? The answer is it’s a little of both. 2007 was ‘sea ice weather’, which can be dramatic from year to year, superimposed on sea ice ‘climate’, which is showing a long term decline (a bit faster than predicted, even if one ignores 2007). This paper seeks to clarify those details and will just be one of many that (I suspect) will reach the same general conclusions.–eric ]

    Comment by Gotta Believe — 6 Apr 2010 @ 1:52 PM

  12. Well done!

    Comment by David B. Benson — 6 Apr 2010 @ 2:07 PM

  13. Martin,

    Thank you for your work and diligence. This article alone is wonderfully illustrative of context and process in care and method.


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    Comment by John P. Reisman (OSS Foundation) — 6 Apr 2010 @ 3:39 PM

  14. This is really great to see this, on so many levels :)

    Since I’m not actually a blogger (this is the only one I attend), RC is sort of like my family, and it’s as if a family member had made good.

    And it’s a feather for RC, that by having this blog, more connections can be made and better science can be advanced.

    Also this sheds true light on the arduous peer-review process, esp trying to get into premier journals. There are plenty of top scientists struggling to get published, so lesser scientists should understand it is nothing personal against them or their ideologies.

    And this shows how the damaging the effects of stolen and posted emails might have been to this piece of science, had it followed, instead of preceded, the CRU hack. We’ll never know what science could have been in the future without the CRU hack. (I’m wondering if corresponding through some other email format, like hotmail or gmail, might help.)

    And last but not least, it’s really great to have some other “thermometer” for global warming, since the denialists take such issue with regular thermometers. So now when they write, “but the temperature data show no warming,” I don’t have to fall back on my “well, look at the ice that’s melting; didn’t you know that heat melts ice?”

    Now I can say, “Well, what about the ocean/sealevel thermometer? Even if the sky might lie (and I’m not saying it does), the ocean certainly doesn’t!” It will also make me look smart, because I now know about this great scientific paper.

    Comment by Lynn Vincentnathan — 6 Apr 2010 @ 3:45 PM

  15. Magnopere!, Martin & Stefan.

    Your seriously cool result reinforces my interest in the possibility of modulating reservoir and lake evaporation and levels in response to future SLR.

    Comment by Russell Seitz — 6 Apr 2010 @ 4:16 PM

  16. Lynn (#14),
    Hotmail and Gmail are services provided by Microsoft and Google respectively, not “email formats”. If your current email service is poorly managed, using a reputable service provider instead might help.
    But what would really help is encrypting messages you don’t want the world to see. You do not need to use a particular service provider or a special email address to encrypt some of your emails. Encryption is an annoyance but it is worth the bother in some circumstances.

    Comment by Anonymous Coward — 6 Apr 2010 @ 4:36 PM

  17. Should we start to evacuate all low-lying areas progressively, is this what they are saying ?

    Comment by Bill — 6 Apr 2010 @ 4:43 PM

  18. My question is can we expect sea level rise to halt or decline with a decline in mean global temperature? I would like to see some specific predictions if possible.

    ——-

    “At the end of the last ice age, the Earth slowly warmed by 4–7 °C globally14 and lost almost two-thirds of its land ice in the process. That raised sea level by 120 metres, at rates often exceeding a metre per century1. It seems that nothing in the present ice-sheet configuration would rule out similar rates in future15. How much of the remaining 65 metres’ worth of land ice will humans melt if we warm the planet by a further several degrees?”
    http://www.nature.com/climate/2010/1004/full/climate.2010.29.html

    Comment by Jimbo — 6 Apr 2010 @ 6:45 PM

  19. “In other words, global sea level would be a good global thermometer, but with a ‘quirk’. I could even think of a physical mechanism for such behaviour.”

    “Slowly it dawned upon me that, hey, maybe I’m on to something real here, something based in physics: it seems the world ocean can be a remarkably good global thermometer, once you get to know its quirks.”

    What do you mean by “good”? Sceptics and alarmists are arguing over small percentage changes in temperatures and you want to use the world’s oceans. Come on!!!!

    Comment by Jimbo — 6 Apr 2010 @ 6:50 PM

  20. Lynn Vincentnathan says: 6 April 2010 at 3:45 PM

    And this shows how the damaging the effects of stolen and posted emails might have been to this piece of science, had it followed, instead of preceded, the CRU hack. We’ll never know what science could have been in the future without the CRU hack.

    Perhaps I’m being too optimistic but I doubt the CRU hack will have much effect on normally unpublished conversations between scientists.

    Square kilometers of newsprint were wasted, gigabytes of disk storage and data transfer were poured down a rat hole, several journalists’ reputations needlessly sullied, a Parliamentary committee found its time squandered, finally to what end? None. There was nothing to hide in the first place, no cause for embarrassment, nothing revealed beyond mundane human feelings. Tiptoeing around the thin skins of prima donnas is not in any researcher’s portfolio of responsibilities and it appears failure to do that was the only thing confirmed by all the gullible hue and cry of the past few months. Exact detail of dull gossip was the only new thing exposed to the public eye.

    The Senior Laundry Sorter hired by CEI– Chris Horner– has tried a repeat performance of demanding then selectively editing and publishing other people’s emails. Though he loves wallowing in the gutter, Horner’s finding little appetite for his wilted salad of mixed sentence fragments. Once the the first thrill of peering into private correspondence has worn off, crushing boredom is the next and more durable response.

    So nothing to hide, no reason to change habits. Smart people recognize this.

    [Response: Bold highlighting mine. That pretty much sums it up — well said.–eric]

    Comment by Doug Bostrom — 6 Apr 2010 @ 6:59 PM

  21. > what do you mean good?
    It’s defined in the paper.

    Comment by Hank Roberts — 6 Apr 2010 @ 7:43 PM

  22. “The impact of Miocene atmospheric carbon dioxide fluctuations on climate and the evolution of terrestrial ecosystems” by Wolfram M. Kürschner, Zlatko Kvaček, and David L. Dilcher:
    http://www.pnas.org/content/105/2/449.full
    to infer an eventual SLR of about 40–50 meters.

    Seattle to become an island at around 10–11 meters SLR.

    Comment by David B. Benson — 6 Apr 2010 @ 8:22 PM

  23. To expand on my last sentence in #3, above:

    Because the oceans occupy a very large portion of the global surface area, and a significant part of the direct radiation is absorbed below the surface, the resulting heating first gets distributed in the mixed ocean layer, before it gets a chance to ‘communicate with’ the atmosphere. That heat remains “in the pipeline” for decades. Part of it is transferred into the atmosphere and then to the land by ‘periodic’ processes like ENSO, AMO, AO, and PDO. These produce large ‘noise’ pulses in the global mean surface temperature (GMST).

    Because of the much larger heat capacity of the oceans – in comparison to that of the atmosphere+land – such noise pulses contribute a much smaller fraction to the ocean temperature. And [except for the small lag in the redistribution of volume associated with uneven heating of (various areas of) the ocean], the absorbed heat-induced-volume increase in sea level is ‘instantaneous’. As a result,”the thin red wiggly curve” in the Sea Level vs Time record (in the above Figure) is a much ‘cleaner’ and more robust representation of global temperature trend than is GMST!

    Thank you Martin and Stefan!

    Comment by Len Ornstein — 6 Apr 2010 @ 8:39 PM

  24. Martin Vermeer:

    Still waiting for Al Gore’s cheque…

    On a dark and stormy night in the near future, a black helicopter will land in your backyard. Two men in fine black Armani suits, wearing black sunglasses, will disembark. You will observe that they are handcuffed to a bulky black suitcase, and surrounded by armed and armored guards, also uniformed in black. They will request to enter your home, and show you the contents of the suitcase in your dining room, after the blinds have been closed and the windows covered with black construction paper. You will do as they ask. You will see the suitcase contains US currency. Small and medium bills – $5s, $10s, $20s, and $50s. 11,000 of each. After seeing the money safely secreted away in your safe, they will erase your memory, and vanish into the night, as mysteriously as they came.

    [Response: Ah, the ol’ memory erasure! I as wondering where all that cash in my office came from!–eric]

    Comment by llewelly — 6 Apr 2010 @ 8:48 PM

  25. This (and Stephan’s comments in Nature) is a good update on the latest for SLR. However, once again I feel this could be too conservative. This makes no accounting of the potential for positive feedbacks such as methane from tundra. Of course, it is only right that it does not as this is science.

    However, as an Engineer, I deal with probabilities of something happening in the future. This requires me to model the likely scenarios. It seems to me that we are already outside the A1B scenario and not likely under the present political atmosphere to be able to get back to it. A1FI is even a bit low for current trends.

    Therefore, I feel the risks justify making some sort of assessment as to what might happen if only ONE of the potential positive feedbacks actually occurs. An ALMOST worst case scenario. I would expect there is sufficient expertise under the IPCC to carry out this sort of analysis. Why, when we are asking the world to take the drastic step of abandoning fossil fuels, has this not been done?

    Comment by Ricki (Australia) — 6 Apr 2010 @ 10:21 PM

  26. This is another pattern for how blogs are actually leading to science. Foster, et al, was another. Well done to all!

    Comment by Eli Rabett — 6 Apr 2010 @ 10:36 PM

  27. Great job. Never imagined a natural phenomenon to produce a 99% Pearson correlation! And now I know which stats handbook to read to get back in shape :-).

    Comment by jyyh — 6 Apr 2010 @ 11:04 PM

  28. CFU “Q: What is the difference between “steep” and “very steep” in your statement ?”

    I would assume “steep” is a rise that is significant and “very steep” is a rise significantly higher.”

    For me that’s a strange definition, significance is related to signal to noise ratio and not to the absolute value of the slope. But admitting your definition, why is the rise at the end of the XXth century more significant than that at the beginning ?

    and for the second question, is it true or false ?

    Comment by Gilles — 6 Apr 2010 @ 11:51 PM

  29. A Rod B sub-thread actually went somewhere!

    Comment by JCH — 6 Apr 2010 @ 11:56 PM

  30. “However, as an Engineer, I deal with probabilities of something happening in the future. This requires me to model the likely scenarios. It seems to me that we are already outside the A1B scenario and not likely under the present political atmosphere to be able to get back to it. A1FI is even a bit low for current trends.”

    The scenario will be mostly constrained by the global amount of fossil fuels we will extract in the century , and this is very poorly related with the current trend. You can relate the current trend with the global curve only with specific hypothesis of the shape of the curve (which can be anything from exponential extrapolation to close peak), and none of these hypothesis has been validated. BTW the “current” trend estimated over the last two years is a – 3% /yr decline.

    Comment by Gilles — 7 Apr 2010 @ 12:01 AM

  31. Gilles #1:

    do you agree that if there is a very long relaxation time, so that the proportionality of the derivative of sea level to the temperature anomaly is a good approximation , then a sea level rise of around 10 meters throughout the next millenium is already unavoidable whatever we do now, since it is very unlikely that we can contain the warming below 2°C ?

    Not necessarily. If by 2100 greenhouse gas emissions have been brought to zero (by that time I expect mankind, or what’s left of it, to have learned its lesson), the CO2 concentration in the atmosphere will start to go down by absorption into oceans and biosphere. As a result, also temperatures will start to go down, but with a delay. Sea level rise will continue as long as temps are above pre-industrial, but at an ever-diminishing rate.

    Then, the assumption of a very long relaxation time doesn’t necessarily hold as such. It was found, I think credibly, by Grinsted at al. 2008 that the “infinite” response time scale term a(T-T0) contains a large component with a finite response time scale of several centuries. The instrumental period is too short to discern this, but it too will lead to a gradual levelling-off of sea level rise after several centuries.

    Comment by Martin Vermeer — 7 Apr 2010 @ 12:16 AM

  32. Congratulations. Reading the paper I can see why Nature eventually declined. They’re after the new and challenging rather than the refinement, and they seem to prefer much terser constructions. A lot could have been lost as result, so better this way.

    I did finally figure the reason for (and implications of) those two different b’s. You might have explained just a little more for us dunces…

    Comment by GlenFergus — 7 Apr 2010 @ 12:50 AM

  33. As an amateur historian/political scientist, it’s wonderful and quite refreshing for me to see the people and proceses at work here! My sincere thanks.

    Comment by Hunt Janin — 7 Apr 2010 @ 1:24 AM

  34. I’d like to echo Doug’s comments in #20. From what I’ve seen the CRU hack has had more impact outside of science than it has on scientists. Partly I guess because the hack is viewed as an anomalous event – it’ll take more than one or two sets of emails being stolen & published for any real change in behaviour – and partly because, outside climate science & the blogosphere, most scientists I know are only vaguely aware of the details of the hack and, frankly, couldn’t care less.

    Comment by Chris S. — 7 Apr 2010 @ 2:13 AM

  35. “[Response: Ah, the ol’ memory erasure! ”

    It’s called the “flashy thing”. There’s a big one in the torch of the Statue Of Liberty.

    Comment by Completely Fed Up — 7 Apr 2010 @ 3:55 AM

  36. To follow up on Bill’s question (no. 17), what would be the effects, worldwide, of a sea level rise of 124 cm by 2100?

    Comment by Hunt Janin — 7 Apr 2010 @ 4:30 AM

  37. The fact that the number of emails exchanged about this one paper = the entire trove of stolen CRU emails may be a hint of selectivity of the theft.

    Your result can’t take into account the threat of a major tipping point, e.g. a large chunk of WAIS floating off, as you hint at the end of the paper. The threat of > 1m sea level rise by 2100 is not a new claim but useful to have further support in the face of the drivelosphere. Good work, and nice that it’s free for all to read.

    Comment by Philip Machanick — 7 Apr 2010 @ 4:59 AM

  38. [spam]

    Comment by Gotta Believe — 7 Apr 2010 @ 6:15 AM

  39. What happens next after this publication ? How is it incorporated into public knowledge and into Govt policy ?

    Comment by Bill — 7 Apr 2010 @ 7:30 AM

  40. Funny how Gotta didn’t think that

    masayo.OGI/2009GL042356-pip.pdf

    in his link didn’t have anything to do with the Ogi in this post:

    “38
    Gotta Believe says:
    7 April 2010 at 6:15 AM

    Can you comment on the Ogi abstract?”

    Then again, it’s a spam link: hosting a sales site and all this barnstack wants to do is sell stuff to the gullible (probably also upping the google rank). Obviously cannot be interested in discussion. Isn’t even listening to what HE says..!

    Comment by Completely Fed Up — 7 Apr 2010 @ 8:53 AM

  41. > Gilles … constrained by the global amount of fossil fuels
    Please keep it in the one topic you’ve taken over. Not again, please.

    > Hunt Janin … what would be the effects, worldwide …
    Specific locations expect different results. I gave you cites long ago.

    > Bill … what happens next
    You read the paper? read the cited papers. Look for more by each author of each paper; watch for new papers citing them over time with Google Scholar.

    Comment by Hank Roberts — 7 Apr 2010 @ 8:59 AM

  42. “At the end of the last ice age, the Earth slowly warmed by 4–7 °C globally and lost almost two-thirds of its land ice in the process. That raised sea level by 120 metres, at rates often exceeding a metre per century. It seems that nothing in the present ice-sheet configuration would rule out similar rates in future. How much of the remaining 65 metres’ worth of land ice will humans melt if we warm the planet by a further several degrees?”

    So dramatic sea level rise is not actually unprecedented, and it could rise regardless of what we do?

    Comment by John — 7 Apr 2010 @ 9:31 AM

  43. “But admitting your definition, why is the rise at the end of the XXth century more significant than that at the beginning ?”

    Not more significant.

    Merely “more”.

    As in “4 could be significant. 8 would be significant too. And 8 is greater than 4″.

    More.

    Comment by Completely Fed Up — 7 Apr 2010 @ 9:55 AM

  44. “and for the second question, is it true or false ?”

    Yes.

    (where is the second question, or if that WAS the second question, what “it” are you asking for?)

    Comment by Completely Fed Up — 7 Apr 2010 @ 9:57 AM

  45. Is it possible that the melting of land ice is, albeit unintentionally, included in this model? There should be some correlation between sea temperature and loss of land ice.

    There seems to be no attempt to account for the increased amount of water that should be present in the atmosphere as it warms. Perhaps it is not a significant amount, but it is certainly part of the water balance.

    There seems to be no attempt to account for the changes in weight distribution on land, and its effect on land elevation. Resevoir water certainly weighs a great deal, and is believed by some to depress land elevation; this may be one of the factors explaining the faster depression of the US gulf coast than would be predicted by sea level rise alone. Melting land ice is believed to increase land elevation. This may be part of the reason southern Alaska’s elevation is increasing relative to sea level.

    I’ve also wondered about the effects of increasing ocean volume: does it cause continents to “float” higher over time? The increasing pressure on the ocean’s bottom perhaps pushes magma under continents.

    Comment by Geno Canto del Halcon — 7 Apr 2010 @ 10:03 AM

  46. Hunt (#36),
    You keep asking basic questions. Demonstrating that you’ve actually done some research based on the information which has been provided to you might motivate people to give you more substantive answers. Rahmstorf’s latest RC post linked to the report of the Dutch Delta Commission for instance which is very informative. Have you read it? Have you read the IPCC litterature on this topic? Have you looked into the controversies surrounding the expensive public works which are carried out around subsiding locales like New Orleans or Venice (Italy)? Have you read about the effect of SLR on irrigation? And so on…
    If you’re undertaking a serious research about this, perhaps you could set up a webpage or a blog about it and lay out some of your findings so as to give back to the community. Perhaps the governments of Bengladesh, Thailand or Nigeria have published pertinent information which has not been adequately communicated to the global public so far for instance. In any case, as a writer, I’m sure you could use your talent to help the public understand the issues you’re researching.

    Comment by Anonymous Coward — 7 Apr 2010 @ 10:13 AM

  47. Ed Greisch at comment 5-
    Thanks for the recommendation of “Probability” It’s not available from my local library but I will track it down for my 9 yr old.

    Comment by Rich Creager — 7 Apr 2010 @ 10:14 AM

  48. Good catch by CFU; the blogspambots are getting really nasty here. That one in 38 copied a name used by a previous poster, but put a link to the spam/malware site behind the name, and copypasted apparently relevant text.

    Big red flag warning folks:
    identical names do NOT mean it’s the same person, or a person at all.

    >> “38 Gotta Believe says: 7 April 2010 at 6:15 AM
    > it’s a spam link

    Needed:
    A blacklist reference, one that ISPs or blog owners can use to filter crap.
    A tool to compare usernames when repeated and flag inconsistent IP addresses.
    A tool to compare the declared user’s blog link to the actual IP posted from.

    Comment by Hank Roberts — 7 Apr 2010 @ 10:17 AM

  49. For Hank Roberts, re #41. I’m very grateful for your input but, understandably, I’d like to know what others think, too. Surely there must be a RANGE of opinions out there…

    [Response: Our other commenters have provided you adequate references whereby you can acquaint yourself with the underlying scientific issues. Your pattern of repeat, off-topic commenting is starting to resemble the behavior of a “troll”. Consider this a warning. -moderator]

    Comment by Hunt Janin — 7 Apr 2010 @ 10:26 AM

  50. @ #39 Bill (7 April 2010 at 7:30 AM)

    What happens next after this publication ? How is it incorporated into public knowledge and into Govt policy ?

    Re public knowledge: it’s up to the newsmedia and science media aimed at the layperson to report items of interest. As well, many non-scientists subscribe to scientific journals in their area of interest (or read them in the library).

    Re government policy: Governments have lots of scientific advisers who maintain a watching brief on new science and inform Government Ministers / legislators when something comes up that has implications for policy. Examples of advisers include the various scientific government agencies, Chief Scientists, government scientific advisory panels, special-ists in key roles eg Department of the Premier/Prime Minister and Cabinet etc.

    (Plea to RealClimate – would it be possible to do something about the spam filter? Could you at least allow us to edit the post when we use a common word like special-ist? I keep forgetting to copy my post before posting :( )

    Comment by Sou — 7 Apr 2010 @ 10:37 AM

  51. Martin, congratulations on contributing to the field. I only hope I can follow in your footsteps. I have two papers at journals now, and I’m hoping like crazy that at least one survives peer review. Getting a paper published in a peer reviewed science journal is one of my life goals. I’ve been trying since I was 17. I’m now 49. Nice bit of deduction in connecting Chao’s reservoir work to yours, by the way.

    Edward (5), I agree about teaching kids statistics. I’d teach them formal logic, too.

    Jimbo (19), What, precisely, are you objecting to? The fact that Vermeer and Rahmstorf tried to analyze a relationship between global temperatures and global sea level? Why is that improper? What’s wrong with it?

    Comment by Barton Paul Levenson — 7 Apr 2010 @ 10:51 AM

  52. Gotta Believe, #11 and #38:

    I’ll comment, except I’m nothing close to a “scientist” (except at heart).

    The Ogi study is a simple statistical correlation between a possible cause and a probable effect, specifically the impact of a particular, variable wind pattern on the rate/degree of ice melt, and the correlation they found is strong. That’s it, no more, no less.

    So… we have a study that is able to correlate certain wind patterns well with some degree of the ice melt. This has apparently contributed the unexpectedly high rate of decline in Arctic ice extent. It is what it is, no more, no less.

    In fact, the Ogi paper is probably a very good parallel with the topic of this post, the paper on sea level rise, in that it took a simple correlation (temperature -> ice extent vs. temperature -> sea level rise) and added the next “principle component” to the equation (a major influencing wind pattern for ice melt vs. a rate of change feedback factor for sea level rise) to help “fill out” the model.

    It’s all about incrementally expanding our understanding of how the earth works.

    Comment by Bob — 7 Apr 2010 @ 11:12 AM

  53. Quick correction to my last post… I frequently used the term “ice melt” which I think is misleadingly inaccurate… I should have said SEI (sea ice extent) as the Ogi paper does, and there is a clear difference between the two, SEI being defined as a specific, common measure (and therefore a proxy of) actual ice melt, but not exactly the same.

    Comment by Bob — 7 Apr 2010 @ 11:25 AM

  54. (Aside to Sou — when you get taken to the spam-filter page, try navigating “Back” — it should take you back to the Reply window and you can edit, copy, etc. and try again.)

    Comment by Hank Roberts — 7 Apr 2010 @ 11:26 AM

  55. Martin,

    You said:

    I could even think of a physical mechanism for such behaviour.

    May I ask you to share that thought? If it is already included in your post, I apologize, but I couldn’t find it.

    Comment by Bob — 7 Apr 2010 @ 11:28 AM

  56. “I keep forgetting to copy my post before posting :( )”

    I use the “Back” button. Even if you are in a view that doesn’t show it, you can or should be able to right click and select “Back”.

    Comment by Completely Fed Up — 7 Apr 2010 @ 11:31 AM

  57. “Surely there must be a RANGE of opinions out there…”

    And we all know opinions are like arseholes. Everyone’s got one.

    If answered, what would you do with it? What would change? Nothing in both cases, really. Nothing you CAN do with it, nothing that would change.

    So questions go unanswered because they are like a broken pencil: pointless.

    Comment by Completely Fed Up — 7 Apr 2010 @ 11:33 AM

  58. Sou says: 7 April 2010 at 10:37 AM

    I keep forgetting to copy my post before posting

    If you use the posting facility provided in the main link to a thread as opposed to the pop-up feature, when you bump into the spam filter you can hit the “back” button on your browser and take as many stabs at cleaning up the post as you like.

    Comment by Doug Bostrom — 7 Apr 2010 @ 11:35 AM

  59. Re;#51Sou & Hank #41 : After another 5 or 15 or whatever ….good scientific papers, will we still be having the same discussion on here? Your comments are great in theory but does the information really get across to the key policy makers in practice??

    Comment by Bill — 7 Apr 2010 @ 1:16 PM

  60. I have what may be a very silly, perhaps stupid, question. Bear with me. I was impressed that freshwater reservoirs had the effect described. This leads me to wonder if the increasing levels of water vapour being held in a warmer atmosphere (rather than precipitating into the ocean) would also alter the sea level-temp relationship as well? Or will more water vapour just mean more precip and there won’t be any noticeable effect?

    btw, thanks for the Jaynes 2003 reference. I’ll check our library.

    Comment by Daniel J. Andrews — 7 Apr 2010 @ 1:16 PM

  61. To further expand on my #3 and #23:

    The Figure (above) of Sea Level vs Time, (and the arguments within the Vermeer & Rahmstorf paper) suggests the first robust ‘explanation’ of the last decade ‘flat’ in GMST:

    It’s almost certainly been due to accidental ‘confluence’ of ‘heat-in-the-pipeline noise’!

    Comment by Len Ornstein — 7 Apr 2010 @ 1:19 PM

  62. This quote from Stefan Rahmstorf commentary in most recent Nature’s issue has probably a typo that needs to be clarified asap:
    “Apart from this being just not so, the melting of all glaciers would add 60 centimetres to global sea level10, a lot more than in the worst-case scenario projected by semi-empirical models for 2050.”
    ojm

    [Response: What’s the typo?]

    Comment by Oscar Mesa — 7 Apr 2010 @ 1:41 PM

  63. Daniel J. Andrews (60) — Extra water vapor (due to warming) is about the same as the contents of Lake Superior.

    Len Ornstein (61) — Another reason to use decadal averages:
    http://www.realclimate.org/index.php/archives/2010/03/unforced-variations-3/comment-page-12/#comment-168530

    Comment by David B. Benson — 7 Apr 2010 @ 2:10 PM

  64. Agreed that the new second and third terms are wonderful additions to the global thermometer. Thanks for the personal tone and the many positive remarks about this important contribution for talking with deniers. My interest generally in RC topics is in the CDR (Carbon Dioxide Removal) topic- and specifically in Biochar. Were that (coupled with massive REDD+ and a few other CDR approaches) to be successful, dT/dt should be able to turn negative this century – maybe even mid-century. Question: should the 80-20 relationship between the second and first terms still hold and the magnitude of the multiplier b remain unchanged? I.e. – to hold sea level constant, would we need to achieve a negative temperature derivative about 1/4 th of today’s positive rate?

    Comment by RonalLarson — 7 Apr 2010 @ 2:45 PM

  65. David, #63 —

    Puzzling… the web says the contents of Lake Superior amount to 12,000 km3 of water, and the surface area of water on the earth is 361,132,000 km2, so taking that water equally from that surface (an assumption)… 12,000 km3 / 361,132,000 km2 = 0.0000332288 km deep, which is 0.0332288 m, or a 33.2288 mm drop in sea level…

    That seems like too much (did I make a mistake in my math? I double checked…).

    Is that the actual increase in water vapor in the atmosphere to date, or on as ultimately expected by a 2C (or some other) warming, but not yet realized?

    Comment by Bob — 7 Apr 2010 @ 2:59 PM

  66. I have a continuing debate with a colleague of mine on the climate change issue. He believes our planet is in a cooling phase as a consequence of it going into a Maunder minimum and other reasons. Nearly all the data and science I point him to on this subject is attacked. He claims the following analysis of the Vermeer and Rahmstorf paper is refuted at:

    http://climatesanity.wordpress.com/

    Perhaps you might comment on this supposed “refutation” of your work with Dr. Rahmstorf.

    Comment by Waqidi Falicoff — 7 Apr 2010 @ 3:58 PM

  67. Waqidi Falicoff (65) — Such solar variations are quite small forcings. HAve him look at 13 decades:
    http://www.realclimate.org/index.php/archives/2010/03/unforced-variations-3/comment-page-12/#comment-168530

    Comment by David B. Benson — 7 Apr 2010 @ 4:32 PM

  68. Fallowing 62
    I understand Glaciers as a general term, as in http://nsidc.org/glaciers/questions/types.html. In that case ” … the melting of all glaciers would add more than 60 meters to global sea level…”. Perhaps you are considering only mountain glaciers?

    [Response: With “glaciers” I meant glaciers and small ice caps, but not the big ice sheets in Greenland and Antarctica. Sorry the reference I gave for those 60 cm (Radic et al, ref. 10) is only in press – it uses the same definition and uses the latest global glacier inventory data to estimate their total volume is worth 60 cm of global sea level rise. -stefan]

    Comment by Oscar Mesa — 7 Apr 2010 @ 4:48 PM

  69. > he believes … a Maunder minimum ….

    I doubt he can still believe that after yesterday’s solar storm.
    Has he looked at what’s going on lately?
    http://www.msnbc.msn.com/id/36201214/ns/technology_and_science-space/
    http://www.swpc.noaa.gov/SolarCycle/sunspot.gif

    Comment by Hank Roberts — 7 Apr 2010 @ 5:03 PM

  70. Bob (65) — I just happened to remember what someone else claimed for the increase in atmospheric water vapor to date; it seems well to check that as well as your math.

    Comment by David B. Benson — 7 Apr 2010 @ 6:05 PM

  71. Martin:”Not necessarily. If by 2100 greenhouse gas emissions have been brought to zero (by that time I expect mankind, or what’s left of it, to have learned its lesson),”

    actually, a fair part of mankind has never really emitted a lot of greenhouse gases, I don’t know which “lesson” you expect from them, but I think you could easily go and live among them, if you like. But it is another issue.

    [quote]
    the CO2 concentration in the atmosphere will start to go down by absorption into oceans and biosphere. As a result, also temperatures will start to go down, but with a delay. Sea level rise will continue as long as temps are above pre-industrial, but at an ever-diminishing rate.
    [/quote]
    could you give a quantitative estimate of the maximum level that you expect with reasonable numerical values, in the best hypothesis ? (CFU , THAT was the second question).

    Comment by Gilles — 7 Apr 2010 @ 6:19 PM

  72. David (70), Bob (65), David(63):

    Wikipedia gives: “The mean mass of water vapor [in the atmosphere] is estimated as 1.27 × 10^16 kg”

    This would be 12,700 km^3, or about the volume of Lake Superior (from Bob(65)).

    This is the TOTAL water vapor content, not the EXCESS due to warming which Daivd presumed(63)..

    Comment by Brian Brademeyer — 7 Apr 2010 @ 6:24 PM

  73. Brian Brademeyer (72) — Thank you for the correction! Excess water vapor is a few percent of that, but I don’t recall the value.

    Comment by David B. Benson — 7 Apr 2010 @ 6:37 PM

  74. Global economy, Gilles (#71.) Increasingly global blogosphere. Of course, the contribution to the CO2 problem has been assymetrical, but the consequences will be widely shared.

    So, yes. I think we’ll all learn our lesson–French, American, Thai, whatever.

    The gist of that lesson will be that our numbers and technology make us dangerous to the environment upon which we depend. Essentially, the lesson that adolescents have to learn in order to survive.

    Comment by Kevin McKinney — 7 Apr 2010 @ 6:39 PM

  75. Brian, #72, David, #73:

    Okay… skepticalscience.com (as reliable as any) gives the % water vapor increase as 6% to 7.5% per degree warming. So…

    12,700 km3 * 0.060 = 762.0 km3
    12,700 km3 * 0.075 = 952.5 km3

    Spread over 361,132,000 km2 gives 2.11 mm to 2.64 mm sea level drop for every full degree of warming. If we’ve seen 0.6˚C of global warming so far, then that’s a 1.27 mm to 1.58 mm to date, or (per year for 30 years since 1980) less than 0.05 mm drop per year due to loss to water vapor.

    Comment by Bob — 7 Apr 2010 @ 8:38 PM

  76. Bob (75) — Thanks.

    Comment by David B. Benson — 7 Apr 2010 @ 8:58 PM

  77. @ #59 Bill
    It’s obvious that governments are getting the messages as evidenced by changes to planning legislation to account for projected sea level rises, attempts to pass legislation to curb GHG emissions etc.

    The problem is less the information getting to the policy makers (if nothing else, they have their IPCC report, which was commissioned by about 190 governments from around the world). The difficulty that policy makers have is getting legislative change quickly enough when there are so many competing interests. Legislators have to deal with short term priorities as well as longer term issues. They are also subject to ‘lobbying’ (aka extortion and bribery) regardless of the form of government.

    Governments often pass legislation after the event. Government as a large ‘enterprise’ has built in intertia, like huge corporations. Medium and small businesses are more nimble and quicker to adopt / adapt to change – look at all the technological developments – solar energy, geothermal, wind power etc – even a solar aeroplane.

    Comment by Sou — 7 Apr 2010 @ 9:12 PM

  78. @ Hank and Doug,
    Re the spam filter: I do use the main board (not the popup), but when I press the back button on my browser after getting the ‘spam’ message, the message box is blank and I can’t retrieve it. (Using IE8).

    I’ll just have to remember to copy before posting – at least until RC can update/amend the spam filter or provide a preview button? (In any case, sometimes I say too much and add little :D)

    Sorry for going OT.

    Comment by Sou — 7 Apr 2010 @ 9:19 PM

  79. So now that we know that the sea level rise is over 1 meter, what do we do with it?

    “To limit global sea-level rise to a maximum of 1 m in the long run (i.e., beyond 2100), as proposed recently as a policy goal (26), deep emissions reductions will be required. Likely they would have to be deeper than those needed to limit global warming to 2 °C, the policy goal now supported by many countries. Our analysis further suggests that emissions reductions need to come early in this century to be effective.”

    Yes. We have to cut CO2 emissions faster and sooner.
    What does somebody who lives in Denver and doesn’t care think? How do we get the senator from Colorado or a coal state to vote for the bill?

    Martin Vermeer and Stefan Rahmstorf have done the fun part. Now we have to do the hard part. Most of the people around me have what I would call smart-Alec answers. They do not take GW seriously, and they will not until some climatic event clobbers them. They probably will not take AGW seriously even then. If they do, they will blame the scientists for causing AGW. “After all, civilization couldn’t have burned all that fossil fuel if you scientists hadn’t invented technology.”

    Sounds crazy? Yes. Insanity is normal. The denialists at least speak English rather than “Word Salad.” Just try talking to some people from a small farming or factory town. You will see what I mean by “the hard part.” They are likely to threaten you for being a commie or an environmentalist.

    How do we proceed from here?

    Comment by Edward Greisch — 7 Apr 2010 @ 9:30 PM

  80. 30 Gilles,

    you miss my point I think, even if the A1B is roughly accurate, it still does not take into account any positive feedbacks or indeed higher early emissions (as we are currently seeing with business as usual). The ramping up of China and India is going to kick emissions along very nicely and it doesn’t look like any effective international agreement is in the wings.

    As Edward Griesch, 79 says, how do we convince people action is necessary NOW and not in 20 or 30 years time! If we wait that long, it will realy be too late for the next 500 years (in my opinion, a collapse of human society into chaos is likely in such a scenario).

    I ask again where are the projections that look at any of the positive feedbacks? The IPCC should be able to do this. Saying that under A1B we get to SLR of 1.2m by 2100 only gives us the lower bound when you think of the potential of the feedbacks.

    Comment by Ricki (Australia) — 7 Apr 2010 @ 10:59 PM

  81. #73 David B. Benson:

    Brian Brademeyer (72) — Thank you for the correction! Excess water vapor is a few percent of that, but I don’t recall the value.

    Actually around 6% for every degree warming from Clausius-Clapeyron, assuming fixed relative humidity. If the total of 33 mm by Bob #65 is right, this amounts to 2 mm/degree for sea level.

    Comment by Martin Vermeer — 8 Apr 2010 @ 12:11 AM

  82. Bob #55:

    > May I ask you to share that thought?

    Yes, it is not in the post… it is briefly mentioned in the article above Eq.(2):

    However, some components of sea level adjust quickly to a temperature change, e.g., the heat content of the oceanic surface mixed layer. Therefore, we here propose to extend the semiempirical method by a rapid-response term:

    Comment by Martin Vermeer — 8 Apr 2010 @ 12:18 AM

  83. Gilles #71:

    could you give a quantitative estimate of the maximum level that you expect with reasonable numerical values, in the best hypothesis ? (CFU , THAT was the second question).

    If I could, I would write a paper on it ;-)

    Actually this is very difficult. It includes guesswork on how mankind is going to behave (I ventured one such guess), and how technology is going to develop (over centuries!), in addition to the physical uncertainties which seem more manageable. In other words, you’re producing ‘scenarios’ or ‘projections’ that are as questionable as the assumptions underlying them. The same problem as we see with the IPCC projections, but worse.

    Comment by Martin Vermeer — 8 Apr 2010 @ 12:38 AM

  84. “So now that we know that the sea level rise is over 1 meter, what do we do with it?”

    No Edward : now we know that sea level rise is over several meters, because it can’t stop before several centuries.

    But as the rate of increase will be one meter /century, the answer is obvious : built absolutely nothing below an altitude of X meters where X is the average life expectancy of what you build. Of course some people will do it nevertheless, but you know, some large cities are also built at the feet of volcanoes or on seismic faults …

    Comment by Gilles — 8 Apr 2010 @ 1:09 AM

  85. ““To limit global sea-level rise to a maximum of 1 m in the long run (i.e., beyond 2100), as proposed recently as a policy goal (26), deep emissions reductions will be required. Likely they would have to be deeper than those needed to limit global warming to 2 °C, the policy goal now supported by many countries. Our analysis further suggests that emissions reductions need to come early in this century to be effective.”

    Sorry to insist, but this statement is simply wrong if Stefan and Martin are right.

    The rise will continue at least throughout the shortest time scale between the damping of the 2°C rise in temperature and the relaxation time of sea level, which is – if they’re right – much larger than one century and could reach 1000 yrs. So the rise CANNOT be stopped in any case at 1 meter level whatever we’ll do, and could reach 10 meters. That is a very robust conclusion IF there is a long relaxation timescale of the order of many centuries. So actually stopping fossil fuels now isn’t the best thing to do- it won’t stop the rise and it would be much more difficult to face the sea without concrete and steel !! . The best thing is to plan mitigation adapted to the unavoidable sea level rise, we just have to choose where to build the future civilization !

    Comment by Gilles — 8 Apr 2010 @ 5:03 AM

  86. Re Gilles #85: yes, it is tough. If we allow temperature to go as high as 2 degrees, the game is probably lost. If we allow temp to stay at 2 degrees, it certainly is.

    BTW the “damping time of the 2 degree rise in temperature” is not a single number — there is a range in time scales, and initially the drop in CO2 will be fast. I don’t think your assertion is anywhere near robust.

    One should read this, page 50 onward, for the thinking behind the statement.

    Comment by Martin Vermeer — 8 Apr 2010 @ 8:53 AM

  87. Zeke #2, Barton #51,

    thank you for your kind words. I wish you well with your own efforts. It is important that outsiders not only are, but are seen to be, able to contribute on merit, that there is nothing like this mythical ‘priesthood’. This was also among my reasons for having our paper Open Access, and accompanied by the code — paywalls suck.

    Now I am only a semi-outsider, having done my dissertation on a geophysics related subject. It’s great to see this amateur and semi-amateur activity take off, with Tamino, Nick Barnes and others. We need this kind of network, or interface layer, between the professional community and society at large.

    Comment by Martin Vermeer — 8 Apr 2010 @ 9:13 AM

  88. Gilles, please stop. You took over one thread already. Don’t go on in every topic, repeating whatever others bring up, then concluding as usual “So actually stopping fossil fuels now isn’t the best thing to do” — we know your conclusion, it’s always the same, no matter what the question. It’s boring.

    Addicts talk like this.

    Comment by Hank Roberts — 8 Apr 2010 @ 10:15 AM

  89. Martin, as you can see here : http://www.realclimate.org/index.php/archives/2010/03/climate-change-commitments/#more-3070 , stopping abruptly any CO2 emission would only result in stabilizing the temperature to current level, so there is actually no hope of getting a sensible decrease of the temperature in the next centuries. As it is extremely unlikely that CO2 emission stops abruptly before at least all cheap conventional resources are exhausted, I think personally that is a waste of time to claim that we should do our possible to limit the sea level rise below 1 meter beyond 2100 since it is already too late. So after what you say, I see only two reasonable positions : either you are wrong and the long relaxation time leading to a quadratic rise doesn’t exist, and the sea level rise will probably be limited and manageable without strong changes. Or you are right and the long relaxation time is predominant, and it is already too late to avoid it, we’d rather manage it as we can.

    Comment by Gilles — 8 Apr 2010 @ 10:51 AM

  90. #66 Waqidi Falicoff says:

    http://climatesanity.wordpress.com/

    1) Download “VR2009 test 4″

    2) Extend Hypothetical Temperature #1 thru #4 to 2100 AD

    3) Ask yourself if those values look reasnoable (Answer? NO!)

    4) Ask yourself why use a deterministic relationship that quickly goes exponential with ludicrous values for temperatures, sea level rates, and sea levels past 2000 AD (which are not shown BTW (I wonder why? NOT!)?

    5) Ask yourself if a deterministic (and unreasonable BTW) relationship is used why not solve the solution analytically in closed form (do the appropriate integrals mathematically versus numerical integration).

    6) Just look at the temperature curves that are shown (ending at 2000 AD) in the following image;

    http://climatesanity.files.wordpress.com/2010/04/test-4-temperature.png?w=449&h=321

    7) GIGO

    Comment by EFS_Junior — 8 Apr 2010 @ 10:55 AM

  91. In the (Feb or Mar 12th, I think) Science, there was a very interesting Item about a Sea Level peak, of ~ 1 M above current levels, at around 82kya (MIS 5-ish), which was based on the study of Calcite Fomrations in Majorcan Caves.
    Because, based on Antarctic Ice Core data, this rise cannot be attributed to CO2 levels being as high as they are now; many would see this as an excuse to nay-say Anthro-forced Glbal Warming.
    I think it’s probably attributable to a concurence of the various Milankovic Cycles leading to increased insolation; and, perhaps, that the subsequent plunge back into Ice Age Conditions was caused by the Toba Eruption at ~ 78 kya.
    It would be nice to see Real Climate offer up an Opinion on this; maybe we could convert Burt Rutan!

    Comment by James Staples — 8 Apr 2010 @ 11:04 AM

  92. Ed (#79),
    You don’t need to convince reactionaries or coal state senators. All you need is 50%+ in most states including some of the biggest. If a minority is dead set against you, you need to work around it by appealing to the majority. It’s pointless to try to convince everyone. How do you think Lincoln got his majority? He wasn’t even on the ballot in the South. Even in Maryland, he got only 2% of the vote. But he got over 50% in most northern states, including the biggest ones.
    Lincoln had righteousness on his side but he also promised people land. Now you can offer them “Fee & Dividend”: most people consume less fossil fuels than the average and would therefore benefit.

    Comment by Anonymous Coward — 8 Apr 2010 @ 11:44 AM

  93. Hank Roberts says: 8 April 2010 at 10:15 AM

    Gilles, please stop.

    Hank, it’s sort of the same deal as getting ExxonMobil to stop selling gasoline. We have to stop using it before they stop selling it. With Gilles, it’s “stop replying.”

    Comment by Doug Bostrom — 8 Apr 2010 @ 12:17 PM

  94. Thanks David, Bob, Brian. I’m less embarrassed about asking that question now but unfortunately am now more embarrassed at the failure of my Google skills. :-( –dan

    Comment by Daniel J. Andrews — 8 Apr 2010 @ 1:36 PM

  95. Martin,

    It seems fundamentally reasonable that the rate of heat going into the oceans would depend on surface temperature.

    However, it looks like you and Stefan do not take into account the process whereby the global temperature, at the surface, would be reduced by the fact of heat going into the oceans. Is that true?

    I continue to think that the global temperature increase will be moderated by heat going into the oceans. Deeper ocean tempertures will continue to rise at a rate needed to keep weather somewhat under control. And of course, this will drive sea levels ever higher.

    Comment by Jim Bullis, Miastrada Co. — 8 Apr 2010 @ 3:38 PM

  96. Hank and Doug : I just post comments about what seems to me interesting, and sometimes erroneous. Possibly the fact that the conclusion is often “ehmm, I’m not sure it’s a good idea to stop now the use of fossil fuels” may be simply due to a frequent occurence of the opposite statement “oh we should obviously stop using fossil fuels” which may not be sustained by a real logical argument and biased by some prejudice- but if my argument about the long timescale is incorrect, I think you have here the opportunity of explaining why.

    Comment by Gilles — 8 Apr 2010 @ 7:34 PM

  97. Ocean pH rate of change, Gilles. Forgetting all else, that’s enough reason to stop burning carbon. You can look this stuff up.

    Comment by Hank Roberts — 8 Apr 2010 @ 10:18 PM

  98. Gilles says: 8 April 2010 at 7:34 PM

    Find a mirror and argue away.

    Comment by Doug Bostrom — 9 Apr 2010 @ 12:20 AM

  99. Jim #95:

    However, it looks like you and Stefan do not take into account the process whereby the global temperature, at the surface, would be reduced by the fact of heat going into the oceans. Is that true?

    Jim, I don’t think so. GIStemp are air temperatures a couple m above the land surface, and something more complicated involving both air and surface temps over the oceans, see Hansen et al. 1996. Above the ocean, air temps closely track water surface temperatures. If T changes abruptly, a heat flux into the ocean is established that rapidly (few years, much shorter than the smoothing time scale of 15 years we use) brings the surface (mixed) layer temperature up to the new equilibrium value, following roughly an exponential decay; and the measured air temperatures will do the same. This rapid-response behaviour is approximated by the b dT/dt term.

    I remember I had a detailed description of this (though not quite this one) in an early draft, but it fell by the wayside.

    I continue to think that the global temperature increase will be moderated by heat going into the oceans.

    And you would continue to think right… this is incorporated in the “secular” a (T – T0) term. The coefficient we found for this deep-ocean part from model runs was around 0.08 cm/year/degree.

    Comment by Martin Vermeer — 9 Apr 2010 @ 12:34 AM

  100. 97. Hank: well – that’s another topics, but that could be an argument indeed. But then you have to state explicitly the amount of carbon above which the acidification of oceans become a problem worse than stopping fossil fuels. It may exist – the problem is only to convince people it is reached.

    Comment by Gilles — 9 Apr 2010 @ 1:13 AM

  101. Re rising tides.
    Tectonic plates move quite rapidly when the globe is cooling, You may witness many earth quakes also because of the shrinking effects of the Earth and the effects of the oceans cooling after 1998 as their related structural movement. Australia and the Antarctic plates are rising and slowly moving north.

    Hence there are may future examples of these happenings in the past when Earth had Little Ice Age period, there were over 90 eruptions, and 4 in 1680 alone, and we have entered into another cooling scale of this same period, beginning around 1998. I noted in the original paper that the graphic stops at 1990 odd. Strange that in 2010, this did not show the decline that has happened.

    The history of Earth is cyclic and found to have the same qualities that have already been expressed by many of the readers of your promotion.

    Comment by Thomas T. S. Watson — 9 Apr 2010 @ 2:32 AM

  102. Gilles, Hank,
    This is a strawman argument. The only way to stop using fossil fuels is through the judicious application of thermonuclear weapons on the world’s population centers and critical infrastructure. No one is seriously advocating this.
    What’s been advocated is:
    1) to burn through the fossil fuels reserves (much) more slowly
    2) CO2 sequestration
    Gilles has provided no argument against 1) or 2). Even modest efforts would mitigate ocean acidification, GW and SLR somewhat. Additionally, 1) would preserve the reserves for later use (for the purpose of adaptating to long-term SLR for instance). What would be the downside exactly, Gilles?

    Comment by Anonymous Coward — 9 Apr 2010 @ 3:31 AM

  103. Hank (88), on Gilles,

    The definition of a fanatic is “someone who can’t change his mind, and won’t change the subject.”

    Comment by Barton Paul Levenson — 9 Apr 2010 @ 4:37 AM

  104. Interesting !
    But I have reservations about the limitations of the methodology.

    Given the dynamics of plate tectonics, the movement of sediments to the oceans by the worlds rivers,Coastal erosion, none of which have been delt with in the paper; how does one determine mean sealevel on a planetary basis with any reliability.
    Sea level rise will combine factors for thermal expansion and icecap melt and plate tectonic movement. A warming of the icecaps with enhanced melting will result in reduced volumes of seawater reaching maximum density and sinking to maintain the superhaline currents, thus slowing the current rather than increasing the deep ocean temperature.

    one of the more intractible problems is the variance of surface sealevel monitoring, in areas of stable plate areas mony monitoring stations show little sealevel rise in the last 100 years, on th other hand a guage on the south of Haiti is now 7 ft out of water while on the north its 7 ft under water. Mountains are being ground down at about thesame rate they are being pushed up, but i’m not aware of any studies on the impact of sedimentation on men sea level.

    We still have a long way to go before we can predict with any certainty into the future.

    Comment by Lindsay H — 9 Apr 2010 @ 4:37 AM

  105. “The history of Earth is cyclic and found to have the same qualities that have already been expressed by many of the readers of your promotion.”

    Only when you postprocess the record and state that there is a median.

    Once that is done, you can look at each time it was higher than that followed by at SOME point a time it was lower than that and say “cyclic”.

    The sun’s output is cyclic.

    It starts off frigid and dark, lights up hotter and then cools down to frigid and dark.

    Cyclic.

    Or maybe using “cyclic” like that (as you have done TS) is complete bollocks.

    Comment by Completely Fed Up — 9 Apr 2010 @ 5:09 AM

  106. Oops, that should have been gilles.

    Comment by Completely Fed Up — 9 Apr 2010 @ 5:09 AM

  107. Waqidi Falicoff #66: Maunder minimum? Tell your buddy to check out the latest satellite AMSU-A data as explained at my blog.

    As to your direct question, why is it reasonable (as in the blog you refer to) to set dH/dt to a constant? Note that the author’s logic requires a temperature trend growing as exp(-at/b). This is a growth rate that rapidly converges to zero, unless you reverse the sign by making one of the multiplied constants (a or b) negative. Big surprise: it results in constant sea level rise when you plug it into the equation given in the paper covered here. Oh and the author fibs slightly about using the same constants as in the paper in his own calculations. In the paper, b = 2.5

    Comment by Philip Machanick — 9 Apr 2010 @ 6:16 AM

  108. 101 AC :”What’s been advocated is:
    1) to burn through the fossil fuels reserves (much) more slowly
    2) CO2 sequestration
    Gilles has provided no argument against 1) or 2). Even modest efforts would mitigate ocean acidification, GW and SLR somewhat. Additionally, 1) would preserve the reserves for later use (for the purpose of adaptating to long-term SLR for instance). What would be the downside exactly, Gilles?”

    Well, I haven’t provided any argument against that simply because it hasn’t been discussed in this thread up to now ;). But since you mention it now, I would answer

    1) I don’t think that burning more slowly the same amount of CO2 will change anything in the long term asymptotic state of the Earth – and the problem is precisely that Stefan and Martin’s theory ASSUMES that sea level rise is a slow change with a very long characteristic time of several centuries. So roughly speaking the final state depends on what has been burnt within this relaxation time, and not on the details of how it has been burnt within it.

    2) CO2 sequestration is technically possible, but it has a cost. But saving fossil fuels is interesting only because they are used to produce wealth. So in some sense, CO2 sequestration goes against saving – it is a waste of energy actually. So again one should carefully investigate if the marginal cost of CO2 sequestration is justified by its benefit. Note that as the externalities of CO2 are CUMULATIVE, it means that the cost increases with the total amount burnt since the beginning of industrial civilization, whereas the benefit is almost constant for a given level of the technique and the economy (which can improve with time of course). It means that the answer is probably that CO2 sequestration becomes interesting above some level of cumulative amount of burnt fossil fuel. Same issue again : which level?

    Comment by Gilles — 9 Apr 2010 @ 7:08 AM

  109. Anonymouos Coward@101,
    Let us know as soon as anyone comes up with a viable carbon sequestration scheme.

    Comment by Ray Ladbury — 9 Apr 2010 @ 7:27 AM

  110. “Well, I haven’t provided any argument against that simply because it hasn’t been discussed in this thread up to now”

    It has several times.

    EVERY SINGLE TIME “use less fossil fuel” comes up, YOU say “can’t be done” or “that would pauper the third world” or “that would ruin the first world economy”.

    But revisionism is the soul of denial.

    Comment by Completely Fed Up — 9 Apr 2010 @ 7:51 AM

  111. “Given the dynamics of plate tectonics, the movement of sediments to the oceans by the worlds rivers,Coastal erosion, none of which have been delt with in the paper; how does one determine mean sealevel on a planetary basis with any reliability.”

    The same way, despite the dynamics of cell growth, muscle relaxation and posture, you can determine how tall someone is quite reliably.

    I.e. those elements are bounded changes.

    Comment by Completely Fed Up — 9 Apr 2010 @ 7:53 AM

  112. > I don’t think burning more slowly the same amount of
    > CO2 will change anything in the long run

    You don’t think about the rate of change.
    You’ve ignored all attempts to point you to the science.
    Rate of change is the fundamental, most important factor.

    Gavin, would I be out of line if I just start posting “Oh shut up” in replies?

    Comment by Hank Roberts — 9 Apr 2010 @ 10:27 AM

  113. CFU :”EVERY SINGLE TIME “use less fossil fuel” comes up, YOU say “can’t be done” or “that would pauper the third world” or “that would ruin the first world economy”.”

    I think you’re slightly OT. The point I raised here was only that if the model of sea level rise with a dL/dt = a(T-To) term is true along the century , it means that there is a very long (1000 yrs or so) relaxation time and that the rise will continue anyway for centuries even if we stop all the warming just now, leading to a several meters rise whatever we do. So saying that “we should do that or that to limit the rise below 1 m after 2100 ” is just an already lost bet : there is nothing that can prevent the rise to carry on at an almost constant rate for centuries. This is just simple maths and I don’t think it has been seriously contested even by the authors of the theory

    Now if OT is allowed, when I say that limiting use of FF will cause more people to be poor, I’m not the only one to say that. For instance saying ” The only way to stop using fossil fuels is through the judicious application of thermonuclear weapons on the world’s population centers and critical infrastructure. No one is seriously advocating this.” implicitely means that we NEED FF – else why should it be a problem to stop their use? and if we need them, then limiting their total amount means that we accept to limit the access to what they are needed for.

    I can accept the theoretical statement that this limitation could be justified in regard to the drawbacks they would produce. But saying “nobody advocates their immediate cut-off” means that this point is not yet reached up to now – just now, it seems still more interesting to burn at least part of them than nothing at all. So my question is very simple : above which level won’t it be the case anymore, and why exactly ? if you can’t offer a precise answer and justification to this, don’t be surprised that many people in the world will rebel against this injunction.

    Comment by Gilles — 9 Apr 2010 @ 10:46 AM

  114. “Gavin, would I be out of line if I just start posting “Oh shut up” in replies?

    Gavin can respond for himself, but I think that you would be simply useless.

    Comment by Gilles — 9 Apr 2010 @ 10:48 AM

  115. Gilles (#108),

    The ultimate effect of fossil fuels emissions are dependent on the time profile of the emissions because there are (very) slow temperature and CO2 concentration feedbacks involved. Lower emissions for a longer time would result in lower CO2 and methane peak concentrations, lower peak temperatures and so on. Please read up on how the known slow feedbacks (albedo, carbon cycle) work.
    Slower emissions would allow for more carbon sequestration, which needs not be very expensive as it should be possible to leverage processes such as photosynthesis or the Urey reaction.
    My understanding is also that it is unlikely that several meters of SLR could be avoided merely by cutting emissions. But it does not follow, as you seem to be implying, that failing to cut emissions would have no consequences.

    Your economic considerations regarding the use of fossil fuels are too abstract. Some uses are currently essential and people derive great benefit (as in staying alive) from them. There are good substitutes for other uses and some uses are simply frivolous. Greater value per mole is derived from the use of small amounts of fossil fuels than larger amounts, as the relationship between the quantity supplied and the price of the fuels demonstrates.
    The desirable level of atmospheric CO2 is more relevant than a total amount emitted would be. As you may know, there is an ongoing campaign to establish 350 ppm as a desirable target. Such levels are political and can not be computed somehow. Even if we had decent values for the climate risks and their physical consequences, you’d need assumptions about long-term social and technological evolution. And you could not reason in monetary terms without assuming a discount rate and monetary values for the lives of unborn individuals or even for civilization itself. In the end, it boils down to how conservative you’re willing to be when faced with poorly understood long-term risks.

    Comment by Anonymous Coward — 9 Apr 2010 @ 10:55 AM

  116. RE- Comment by Hank Roberts — 9 April 2010 @ 10:27 AM:

    You are trying to deprive poor Gilles of his rambling and vacuous essay hobby. Shame on you.

    Steve

    Comment by Steve Fish — 9 Apr 2010 @ 11:12 AM

  117. AC # 115 : again, my posts here were only relevant to sea level rise. If the relaxation time is very long (many centuries, maybe 1000 yrs), all what you mentioned is mainly immaterial as long as the timescale involved is shorter. All the other points would deserve discussion, but it would be clearly OT and I would certainly be accused again of developing my .. ehhm. rambling and vacuous ideas. The only point I would stress is that on the century timescale, all fossil fuels will have been exhausted and that the “long term risks ” will probably have a totally different nature that what we can imagine now. Imagining the consequences of warming and sea level as if it would impact a society close to our current one is probably totally irrelevant.

    Comment by Gilles — 9 Apr 2010 @ 12:16 PM

  118. Martin, Thank you for your #99 answering my #95.

    Following up on that, it would seem that a much shorter smoothing time scale, than the 15 years that you use in modeling, would result in a significantly faster rise in sea level than the .08 cm/yr/deg that now is the outcome of model runs. Is there a way to know what it would be if the smoothing time scale was 3 years, for example?

    As I understand what you are saying, this would also make the predicted temperature increase come out at a lower number.

    Then it might make sense to discuss why the right number is 15 years.

    Comment by Jim Bullis, Miastrada Co. — 9 Apr 2010 @ 12:27 PM

  119. Gilles (#117),

    No, the timescale involved isn’t shorter. The timescale is in part exactly the same, for instance because the mixing rate of the ocean’s waters is a factor in the sea level as well as the atmospheric CO2 concentration.

    Fossil fuels need not be depleted as fast as the current unsustainable consumption trajectory would imply. Your logic apparently goes like this: fossil fuels are going to be depleted soon anyway so there’s no reason to burn them slower. That’s circular logic.

    Again, future temperatures and therefore future SLR will depend among other things on the rate of fossil fuel consumption. Just because some SLR is bad doesn’t mean more SLR isn’t worse. And just because much of the impact would take place over centuires doesn’t mean there will be no short-term impact. People are building and are planning to build infrastructure the usefulness of which will depend among other things on the rate of emissions in the coming decades.

    Comment by Anonymous Coward — 9 Apr 2010 @ 2:25 PM

  120. To 90 (Efs_Junior) and 107 (Philip) Thanks for your comments. I have passed them on to my colleague.

    Comment by Waqidi Falicoff — 9 Apr 2010 @ 2:35 PM

  121. Waqidi Falicoff 120: my comments got snipped partway through for some reason. This is a small fraction of the problems in the article you referred to. Your colleague should download the spreadsheet if he (or she) has any numeracy at all and will find that the whole thing is a total fraud: the formulae for the graphs on the site bear no relationship to the calculations in the spreadsheet.

    Comment by Philip Machanick — 9 Apr 2010 @ 3:50 PM

  122. AC : No, the timescale involved isn’t shorter. The timescale is in part exactly the same, for instance because the mixing rate of the ocean’s waters is a factor in the sea level as well as the atmospheric CO2 concentration.”

    As I understood, mixing of layer is not enough to account for a very long time scale and other phenomena must be considered, e.g. the melting of land ice caps. And this cannot be stopped if the theory is correct.
    “Your logic apparently goes like this: fossil fuels are going to be depleted soon anyway so there’s no reason to burn them slower. That’s circular logic.”

    that’s not exactly what i’m saying : I think that the total amount of fossil fuels we can burn in the century will never reach this characteristic level (that I am asking you to ascertain) at which the cost of externalities will exceed the benefit they produce (which doesn’t mean of course that this cost doesn’t exist, but it will remain limited and manageable ). So actually it will never be interesting to reduce willingly the global amount we will burn. The rate at which they will be burnt is almost immaterial, but they will probably follow a bell shaped, Hubbert-like curve.


    Again, future temperatures and therefore future SLR will depend among other things on the rate of fossil fuel consumption. Just because some SLR is bad doesn’t mean more SLR isn’t worse.”

    Sure. I said that we can’t avoid several meters, but the choice would rather be between 10 m and 20 m if Stefan and Martin are right. So it could make sense to say “let’s reduce the amount of fossil fuel so that people in 1000 years have only 10 m instead of 20 meters”. Or it could also make sense to say “well the sea level will rise a lot anyway, so we’ll have to move away from the coast lines gradually, and the current cities on shore are doomed anyway. So it won’t cost a lot more to rebuild them farther inland. In any case, this will happen on a time longer that the life expectancy of what we build”. That’s an interesting debate.

    Comment by Gilles — 9 Apr 2010 @ 6:01 PM

  123. #104 Lindsay, you might want to check my post on sea level variations on the Climate & Network connections.

    Comment by J. Bob — 9 Apr 2010 @ 6:26 PM

  124. Interesting article! (Loved the Freeman Dyson article, too.)

    The most often-cited paper about sea levels these days seems to be Church & White (2006), A 20th century acceleration in global sea-level rise. They detected a 20th century acceleration in sea level rise of 0.008 ± 0.008 mm/yr^2 (and a larger acceleration if 19th century data was included). Although they noted that “no 20th century acceleration has previously been detected” by other researchers, their paper is widely referenced in support of the belief that the rate of sea level rise has accelerated in response to anthropogenic factors, especially the soaring CO2 emissions in the last half of the 20th century.

    So what does that mean for sea levels in 2100?

    Not much. Church & White now have newer data available (through 2007 instead of 2001), which shows considerably less acceleration than the previous data did. What’s more, despite their 2006 report of 20th century acceleration, there’s a very good reason to expect that the rate of sea level rise will not accelerate at 0.008 mm/yr^2 over the next 90 years. The reason is that (according to their latest data) it has not done so over the last 90 years.

    In fact, when calculated using Church & White’s methodology and their latest data, the rate of sea level rise actually decelerated at 0.006 mm/yr^2 over the last 90 years for which they have data (1917 to 2007).

    C&W’s methodology for calculating the acceleration is simple. They plot the GMSL (globally averaged, corrected & reconstructed mean sea level), and fit a quadratic curve to it via regression analysis. The acceleration is twice the quadratic coefficient.

    Microsoft Excel can fit quadratics (Excel calls such fitted curves “trendlines”). So I downloaded C&W’s latest data, loaded it into Excel 2000, selected the last 90 years, generated an Excel X-Y “chart,” and fitted a quadratic to it. Here’s the graph:
    http://i831.photobucket.com/albums/zz231/ncdave4life/church_white_1917-2007_trimmed-1.gif
    And here’s the spreadsheet:
    http://www.burtonsys.com/climate/church_white_2009_gmsl_90yr.xls

    As you can see, the quadratic term is negative 0.0031, indicating deceleration of 0.0062 mm/yr^2.

    Of course, -0.0062 mm/yr^2 is a very small deceleration. If continued for 90 years, it would amount to a decline in rate of global mean sea level rise of only about 0.56 mm/yr. (Likewise, C&W’s reported +0.008 mm/yr^2 20th century acceleration was also very small.)

    Now, I’m not claiming that the rate of sea level rise is actually decelerating. It is possible to cherry-pick starting points to show either acceleration or deceleration of sea level rise during the last century, using Church & White’s data and method. For instance, using 1940 as the starting year shows deceleration, and using 1950 as the starting year shows acceleration. Likewise, choosing the last 100 years (1907 to 2007) yields a very small acceleration, and choosing the last 95 years (1912 to 2007) yields a very small deceleration (though in both cases the amount is so tiny that the quadratic curve appears to be perfectly straight).

    The truth is that the tide gauge data for mean sea level for the last century is simply a straight line plus noise. There has been no measurable sustained acceleration or deceleration, regardless of whether you use the GLOSS-LTT tide gauges (individually or averaged), or Church & White’s latest data.

    However, I have concerns about the reliability of C&W’s “corrected” data. It indicates a linear trend which is substantially higher than that which the GLOSS-LTT tide gauges show. The reason is probably given in this remarkable admission in paragraph 5 of their paper:

    “An additional spatially uniform field is included in the reconstruction to represent changes in GMSL. Omitting this field results in a much smaller rate of GMSL rise…”

    In other words, they added an ad hoc fudge factor! They didn’t directly say whether that “correction” in rate of GMSL rise was temporally uniform, but if so then it would affect only the linear trend, not the quadratic coefficient. So perhaps the acceleration/deceleration calculations are correct. Still, I’d like to know exactly how they processed the data before I completely trust it, even for calculating acceleration & deceleration.

    Dave

    Comment by Dave Burton — 10 Apr 2010 @ 12:46 AM

  125. Gilles (#122),

    The melting of ice caps is a feedback as well (through albedo) which in turn affects other feedbacks including the melting itself. I hope you can see that the timescales actually overlap. Not that it matters much but that was your arugment.
    You’re writing that the melting “cannot be stopped if the theory is correct”. But the theory is only about what would be likely to happen without intervention. Melting is maily a function of temperature and solar radiation. And aerosols could lower both and therefore halt the melting (at least if emissions were cut as well). You might argue that loading the startosphere with aerosols would be unwise but I don’t think you’d argue it can’t be done.

    You wrote “on the century timescale, all fossil fuels will have been exhausted”. I’m glad you recognize now that this is not likely to be the case as a bell shaped curve of sorts is indeed expected (note that people also expect a long tail) but you keep clinging to your absurdly simplistic economics.
    There is no “characterstic level” at which it would be rational to stop using fossil fuels. Would you have fossil fuels consumption continue without restriction until some day when it’s cut down to zero because some abstract threshold has been reached? How practical would that be? Please take a look at what’s actually being proposed: a gradual decrease in fossil fuel consumption.
    Clearly, some of the consumption of fossil fuels today “produces” little to no benefit. The benefits/externalities line has been crossed generations ago by a growing share of the amount burned. This line goes across today’s consumption which is why people have been arguing that the consumption should be slowed and not either increased or cut to zero as your economics would have people believe is best.

    Finally, do you have any idea of how the consequences of 10m and 20m of SLR differ? Surely you understand it’s not only a matter of rebuilding some cities (nevermind that the amount of rebuilding would vary).

    Comment by Anonymous Coward — 10 Apr 2010 @ 3:38 AM

  126. Impressive story, and impressive study.

    “refutations of silly null hypotheses” ,made me think about the long discussion on my blog, where eg the null hypothesis of extrapolating a linear trend was refuted. http://ourchangingclimate.wordpress.com/2010/03/01/global-average-temperature-increase-giss-hadcru-and-ncdc-compared/

    Comment by Bart Verheggen — 10 Apr 2010 @ 5:31 AM

  127. Baron de Rais: Eat, drink, and be merry, for tomorrow we die.
    Guillaume the Warmer: But your doing so at such a great rate is what will CAUSE us to die!
    Baron de Rais: Are you trying to make everybody poor?

    Comment by Barton Paul Levenson — 10 Apr 2010 @ 8:20 AM

  128. AC : I’m afraid you don’t really understand what a relaxation time scale is. If two time scales are involved, they don’t “overlap” : the longer wins over the shorter (at the longest time scale, all others seem to reach a quasi-equilibrium). Again referring to this figure http://www.realclimate.org/index.php/archives/2010/03/climate-change-commitments/#more-3070 , the characteristic time scale for temperature relaxation is not more than 100 years. If the relaxation of sea level with respect to temperature change is also of this order of magnitude, basically Stefan and Martin’s equation is not very accurate since a fair part of relaxation has already occured, and extrapolation at 100 years is not justified – actually we would be in an “intermediate” relaxation state where more accurate differential equation should be used. Their approximation of dL/dt propto (T-To) is admissible only if the timescale is much longer (they mention about 1000 years), in which case what I said applies : you can’t stop the rise for one millenium, whatever you do. In other words, either we can control rapidly the sea level rise, but in this case it reacts rapidly to temperature and the asymptotic level is not expected to be high (less than 1 meter as IPCC claims). Or the rise is on much longer timescale, it will be much larger, but we can’t act on it below century scale. There is no space (or very little may be for a very restricted narrow range of parameters and an very specific definition of the “dangerous” level and the “admissible” level) for “the rise will be very high if we don’t react rapidly” – although this may be the most popular slogan, it doesn’t correspond to any physical situation : if the rise threaten to be high, the system can’t react rapidly and if it reacts rapidly, it can’t be very high.

    Comment by Gilles — 10 Apr 2010 @ 11:01 AM

  129. Gilles,

    Your reasoning is too simplistic and abstract. Please keep the physical processes in mind. There are more than two time scales involved and, instead of “winning”, they feed back into each other. It follows that only the fastest processes will be allowed to reach equilibrium before the whole system does. There are much slower processes than ice sheet response or ocean mixing such as weathering by the way.
    In the case of the sea level, it should be obvious that SLR would slow and that the sea level would be set on course for a lower equilibrium if temperatures dropped. No unphysical process would keep the SLR from decelerating (and eventually stopping if temperatures fall low enough). You can only use Rahmstorf & Vermeer to argue for an unavoidable centuries-long SLR by assuming that temperatures can not be brought down to begin with.

    You are not linking to anything like the relaxation time scale for temperature (whatever that means physically). It looks like what you are linking to is basically ocean/atmosphere CO2 exchange combined with Charney feedbacks (but I may well be reading it wrong). In any case, the figure does not show how temperatures are thought to respond to a forcing. Instead, the forcing itself is simulated. As noted in the comments, the scenario simulated is a geoengineering scenario (although the authors apparently neglected to state it). In this scenario, you would definitely not have anything like 10m of SLR because temperatures would drop relatively fast. As it happens, this is the kind of scenario I had in mind in my last reply (#125) when I told you a large SLR was not a done deal.
    If you want to look at the temperature relaxation time scale (although I think the concept is meaningless), I would suggest you look at the famous “Target atmospheric CO2″ paper which talks about “several millennia”.
    The time scale of CO2 exchange between atmosphere and oceans is more relevant to long-term SLR in an emissions reduction scenario anyway.

    In closing, the systems reacts rapidly as well as slowly. The slow response is the one liable to cause the most damage but the fast response is the one that is likely to dominate in the near future. This is why Rahmstorf & Vermeer use a “dual model” (though there are more than two distinct processes in reality).

    Comment by Guillaume the Warmer — 10 Apr 2010 @ 5:57 PM

  130. I find Stefan’s argument (in the linked Nature article) that increasing air temperatures at the poles will allow increased contributions to sea level rise from ice sheet melting to compensate the loss of glacial melt water. I’ve not heard this argument before, though the data on increased surface melt at Greenland tends to support this. Could you elaborate on this one of these days?

    Eric made a comment a while back that seemed to indicate that he didn’t think polar ice sheet melting would continue to accelerate. I think he was talking about bumping up against the limits of ice sheet dynamics discussed by Pfieffer (?).

    Comment by Andrew — 10 Apr 2010 @ 10:41 PM

  131. G the warmer:”In the case of the sea level, it should be obvious that SLR would slow and that the sea level would be set on course for a lower equilibrium if temperatures dropped. No unphysical process would keep the SLR from decelerating (and eventually stopping if temperatures fall low enough). You can only use Rahmstorf & Vermeer to argue for an unavoidable centuries-long SLR by assuming that temperatures can not be brought down to begin with.”

    I fully agree. But in which scenario would the temperature decrease and what would be its average value over one millenium ?

    Comment by Gilles — 11 Apr 2010 @ 12:32 AM

  132. From Stefan’s Nature commentary: “But this view considers only surface mass balance, without taking account of the kind of rapid, nonlinear ice-flow changes that some glaciologists expect for the future.”

    That would mean that, taking into the account the very good fit with past measurements, this semi-empirical approach could serve as a warning system for future changes: If future sea level rise starts to become significantly larger than predicted by such approaches, that could signal that such rapid, non-linear contributions (from destabilizing ice sheets) are increasing.

    Comment by Bart Verheggen — 11 Apr 2010 @ 8:42 AM

  133. As the ocean temperatures have been flat since 2003, I am curious what is purported to be causing the planet’s ocean to currently rise at the rate you are suggesting.

    (i.e. Sea level rises due to increase in water temperature, increase in ocean mass (more water), or due changes in ocean floor level (geological time period, not relevant for this discussion.)

    A simple mass balance calculation shows there is not sufficient ice melting to support the sea level rise rate you are suggesting.

    Can anyone answer this question?

    Mass and volume contributions to twentieth-century
    global sea level rise

    “The rate of twentieth-century global sea level rise and its causes are the subjects of intense controversy1–7. Most direct estimates from tide gauges give 1.5–2.0 mm/yr, whereas indirect estimates based on the two processes responsible for global sea level rise, namely mass and volume change, fall far below this range. Estimates of the volume increase due to ocean warming give a rate of about 0.5mmyr21 (ref. 8) and the rate due to mass increase, primarily from the melting of continental ice, is thought to be even smaller. Therefore, either the tide gauge estimates are too high, as has been suggested recently, or one (or both) of the mass and volume estimates is too low.”

    http://www.grdl.noaa.gov/SAT/pubs/papers/2004nature.pdf

    http://www.sciencemag.org/cgi/content/figsonly/327/5967/860

    “Sea-Level Highstand 81,000 Years Ago in Mallorca
    Global sea level and Earth’s climate are closely linked. Using speleothem encrustations from coastal caves on the island of Mallorca, we determined that western Mediterranean relative sea level was ~1 meter above modern sea level ~81,000 years ago during marine isotope stage (MIS) 5a. Although our findings seemingly conflict with the eustatic sea-level curve of far-field sites, they corroborate an alternative view that MIS 5a was at least as ice-free as the present, and they challenge the prevailing view of MIS 5 sea-level history and certain facets of ice-age theory.”

    Comment:
    For those who are interested in scientific puzzles. Why sea level has risen and fallen in the past is curiously controversial.

    In the past there has been very rapid rises and falls of sea level that are too rapid, to have been caused by changes in the ice sheet masses. (During the last glacial period.) It appears something cyclic is causing the sea level to rise and fall. (i.e. The mass of the ocean remains essentially the same. The rise and fall of the sea level in the past does not align with planetary temperature changes. It is too early. An example of the cyclic sea level rise is during the odd Heinrich events.)

    [Response: First of all, would you people out there please just quit with the ‘temperatures have been flat since (pick a date that works). Trends shorter than 15 years are pretty much meaningless. Why don’t people get this? Second the paper you cite does not conclude that there is any kind of mystery. They are simply saying that the various estimates of sea level rise, ocean expansion due to temperature, and ice mass loss are all uncertain, and it would be nice to be able to close the budget. Their conclusion is that the “mass increase plays a larger role than ocean warming in twentieth-century global sea level rise.” In other words, more ice has been lost than we thought, but ocean warming is still part of the picture. As for Heinrich events, yes, there is evidence for rapid changes in sea level not due to temperature, and the changes are so massive that glaciologists find it a bit startling that so much ice can calve from ice sheets into the sea in such a short time. But that’s what happened, and certainly indicates we have work to do in better understanding how ice sheets work. But the Heinrich events are ‘cyclic’ and have nothing to do with current sea level rise.(Which raises another question: where do people get the idea that saying “it must be a cycle” provides an explanation of anything?)–eric]

    Comment by William — 11 Apr 2010 @ 9:09 AM

  134. Thank-you for your comment.
    The relative unexplained ocean level change in current times seems to be small however it is significant in terms of the necessary mass balance change or ocean temperature change that would be required to cause the ocean level to change the purported amount. A simplified calculation shows the current ocean level change cannot be explained by ice sheets melting or by ocean temperature change.

    The Heinrich ocean level change was a fall and rise of ocean level of 10m to 15m which is easier to see as a puzzle. It is not possible for the ice sheets to loss and gain sufficient mass (melt and then gain mass due to snow fall)to cause the ocean level to fall and then rise 10m to 15m in the Heinrich time period (Roughly 1000 years.) As it is physically not possible for the ice sheets to lose (the planet does not warm up sufficiently during the Heinrich event time period, there is no physical mechanism that can move ice sheets off of the continents). It seems there must therefore be a third parameter that is causing the ocean level to change.

    My point is a cyclic event (Heinrich changes including ocean level changes) requires a cyclic forcing function and that the forcing function must explain what is occurring during the event.

    http://geochemistry.usask.ca/bill/courses/International%20Field%20Studies/Sea%20level.pdf

    “Sea Level Change Through the Last Glacial Cycle

    Furthermore, the pre-LGM period is characterized by substantial fluctuations in sea level of 10 to 15 m about every 6000 years. The timing of these rapid change events during oxygen isotope stage 3 (OIS–3) apparently coincides with Heinrich ice-rafting events recorded in North Atlantic sediments (61), which suggests that they reflect major ice discharges from continent-based or shelf grounded ice sheets (62).”

    Comment by William — 11 Apr 2010 @ 10:31 AM

  135. Gilles,

    The scenario you linked to in #128 is one such scenario but it’s not realistic.
    A halfway-realistic scenario in which temperatures decrease soon enough to mitigate a large SLR would in my opinion involve a combination of the following:
    1) emissions reductions
    2) CO2 sequestration
    3) geoengineering
    I don’t think one of these on its own would realistically be enough with current technology unless perhaps extreme measures are taken. For instance I don’t think emissions can be reduced to anywhere close to zero in the forseeable future.

    As to the average temperature over a millenium in such a scenario, it would of course depend on the particulars of the scenario but there are also considerable uncertainties as to the workings of the climate system as you must be aware. I’m not qualified to propose realistic numbers but professionals have done so for other scenarios and I think we can extrapolate from that. I refer you to IPCC AR4 WG1, 10.7 for instance.
    Irrespective of the uncertainties, it should be obvious that, if an effective geoengineering (and/or GHG sequestration) program aimed at controlling the SLR among other things ever gets started, a higher temperature peak would imply a slower return to the target temperature and therefore a much higher unavoidable SLR. This is why substantial emissions reductions in the next decades would leave more options open to future generations.

    Comment by Guillaume the Warmer — 11 Apr 2010 @ 11:20 AM

  136. The inline rebuttals are excellent, but (sigh) it doesn’t seem to stop the stuff coming back.

    I’m starting to wish y’all could apply a strikeout or light gray font color or something to flag the bogus rebunking claims when they reappear.

    Arguing with repeated pasting of the same bunk never seems to help.

    Comment by Hank Roberts — 11 Apr 2010 @ 11:37 AM

  137. William points to a link to an online copy of a 2001 Lambeck and Chappell paper after claiming it’s impossible to explain changes of sea level happening in 1000 years, then argues some unknown effect must be hiding.

    What does that paper actually say?

    “… the rate of melting has been variable: In two periods of rapid and sustained sea level rise from about 16,000 to 12,500 and again from 11,500 to 8000 years ago, the rates of equivalent sea level rise approached 15 m in 1000 years (16, 17, 31)….”
    and then discusses
    “… substantial fluctuations in sea level of 10 to 15 m about every 6000 years. The timing of these rapid change events during oxygen isotope stage 3 (OIS–3) apparently coincides with Heinrich ice-rafting events recorded in North Atlantic sediments (61), which suggests that they reflect major ice discharges from continent-based or shelf-grounded ice sheets (62).”

    That paper doesn’t say the change is impossible; it discusses changes and the uncertainties in what we know about both ice and land.

    It doesn’t say there are gaps that require some unknown additional forcing to explain them, however.

    Look at the reference at the original site, here:
    http://www.sciencemag.org/cgi/content/abstract/292/5517/679
    “Observations of glacially induced sea level changes also provide information on the response of the mantle to surface loading”
    Look at the citing papers from the link there as well.

    Then click the links for citing papers to see subsequent work in the area.

    Comment by Hank Roberts — 11 Apr 2010 @ 12:42 PM

  138. Accordings to Matthews (2009) (http://www.nature.com/nature/journal/v459/n7248/full/nature08047.html),
    the effect of carbon emissions is proportional to the cumulative emissions and “the total allowable emissions for climate stabilization do not depend on the timing of the enmissions”. I read the paper a while ago and as far as I remember it validates Gilles’ argument that all that matters (on a timescale of decades to centuries) is the sum total of emissions and slowing down will have no discernible effect on the temperature reached at the end. Also even if Gilles is not right on the relaxation time (Martin says it’s far from clear whether it’s as bad as he proposes), he is of course right in saying that sea level will continue rising for some centuries even after an emission stop (see Plattner 2008, Long-term climate commitments). Also, as Martin rightly said in reply to Gilles, if we reach 2 degrees K (the climate target of many countries), we will be in sea level trouble. In my view it’s rather probable that with 2 K we will get the same sea level as during the last interglacial with the same temperatures (eg ca 6 m higher).
    So in many ways, even though Gilles may be a bit repetetive, his arguments are not spurious and should be treated with due respect and seriousness.

    Comment by C. Streif — 11 Apr 2010 @ 1:57 PM

  139. In reply to comment #137 Hank Roberts

    Hank,
    What are you suggesting caused the sea level to change 10m to 15m every roughly 6000 years coinciding with the Heinrich events?

    During the Heinrich events the sea level rises and then falls 10m to 15m.

    If the entire Greenland Ice Sheet were to melt (2.85 million km of ice) global sea levels would rise 7.2 m (23.6 ft.) (IPCC 2001).

    Why are sea levels currently rising? Mass or temperature?

    Comment by William — 11 Apr 2010 @ 2:07 PM

  140. Hank Roberts says: 11 April 2010 at 11:37 AM

    I’m starting to wish y’all could apply a strikeout or light gray font color or something to flag the bogus rebunking claims when they reappear.

    I heartily agree with this. There really ought to be a way of letting folks express themselves here yet at the same time providing some sort of early warning about the relative worth or worthlessness of an assertion.

    On the thread concerning Der Spiegel, RC is making an admirable attempt to reset the tone of conversation on the site. Though I’ve thrown many logs on the fire of outrage myself, it’s a necessary change. Yet it is a sad fact that some people undeniably (heh!) use this site to propagate frankly incorrect and misleading talking points such as “the Arctic ice has recovered.” Hearing these repeated ad nauseam only to be laboriously deconstructed over and over again obviously taxes the patience of even the most saintly (such as Hank), inevitably inviting a breakdown in comportment.

    Since all posts are scanned by actual people here prior to posting, perhaps the most rank and decayed wrong assertions could be highlighted? A simple change, really, perhaps a useful middle way.

    Another tweak would be simply to set a budget on comments by an single person during a given period of time. As I understand the original intent of the site was to help people understand the science of climate change as opposed to simply being a venue for argument, but on the other hand arguments do unveil lots of interesting information.

    If all this is too off-topic please feel free to delete…

    Comment by Doug Bostrom — 11 Apr 2010 @ 2:20 PM

  141. Martin & Stefan:

    Beautiful, concise and limpid paper. Congratulations! The results reflect the fact that, since the heating constant of the ocean is so much greater than that of the atmosphere, we can clearly see the effects of climate change on sea levels because the signal is unencumbered by the noise caused by atmospheric weather. Adding data from man-made reservoirs and introducing a time-lag constant that accounts for a decade-long mixing time of the top 100 m of the ocean is simply a stroke of genius and advances our understanding of hydrosphere behavior caused by global temperature variations. Accurate and precise prediction of the 1815 Tambora eruption is deeply satisfying, if not stunning. The model reflects reality. Period. End of story. The rhetoric stops here!

    Well done!

    Denys F. Leclerc, Ph.D.

    Comment by Denys F Leclerc — 11 Apr 2010 @ 4:51 PM

  142. C. Streif (#138),

    This contrarian letter in Nature seems to have been written by the same Matthews who apparently neglected to take aerosols into account in his recent letter to Nature (see Gilles’ link). I would caution against giving it too much weight without giving careful consideration to the framework and assumptions that underly such statements as “the warming per unit CO2 emitted does not depend on the background CO2 concentration”. I would certainly have to reconsider my assertion that the effect of emissions is dependent on their timing if it was indeed the case that Matthews had overturned the conventional relationship between CO2 atmospheric concentration and warming.

    As to Plattner, you may notice odd similarities between that paper and the section of AR4 I just referenced. You may also notice thats it is at odds with your Matthews quote (both can not be right).
    Please note also that Gilles actually agrees with me about SLR: it will depend on the actual temperature curve and not on arbitrary assumptions or models. Models generally assume inaction (and rightly so). But to use this assumption in an argument against action amounts to circular reasoning.

    [Response: Did he really say “the warming per unit CO2 emitted does not depend on the background CO2 concentration”?!? This is totally wrong!–eric]

    Comment by Anonymous Coward — 11 Apr 2010 @ 6:12 PM

  143. > William
    > Why are sea levels rising?
    http://nsidc.org/sotc/sea_level.html
    http://www.google.com/search?q=site%3Arealclimate.org+Why+are+sea+levels+currently+rising%3F

    > C. Strief
    > the effect of carbon emissions is proportional to the cumulative emissions
    > and “the total allowable emissions for climate stabilization do not
    > depend on the timing of the enmissions”.

    Look more carefully at the Supplementary Information. They’re not talking about “the effect” — on the world and the biosphere. Neither is Gille

    They’re talking about a particular measure useful to compare models:

    “… The climate-carbon response (CCR) … aggregates both climate sensitivity…, a newly-defined carbon sensitivity (the airborne fraction of cumulative carbon emissions), and the effect of carbon cycle feedbacks on both the airborne fraction of emission and the resulting climate change. We have additionally shown that the CCR is approximately independent of both CO2 concentration and its rate of change ….

    That ignores, for example, ocean pH — increasing very fast. Natural cycling is currently handling about half the fossil-fuel CO2 we put into the atmosphere. The leftover is what’s increasing in the atmosphere and ocean.

    Cut back burning the fossil fuel far enough and the ocean pH quits changing.
    http://www.realclimate.org/index.php/archives/2005/07/the-acid-ocean-the-other-problem-with-cosub2sub-emission/
    http://www.realclimate.org/index.php/archives/2007/11/is-the-ocean-carbon-sink-sinking/

    Can you possibly imagine that makes no difference in the outcome?

    Comment by Hank Roberts — 11 Apr 2010 @ 6:27 PM

  144. Eric,

    Yes, that’s what he wrote but I have quoted him out of context, just like C. Streif did. The full letter with the footnotes should explain it but it’s beyond a paywall. I suppose the idea is that carbon cycle feedbacks would compensate for the lower forcing per mole as the concentration rises although it’s odd that they would compensate exactly. Presumably this relationship only holds within fairly narrow parameters, if certain assumptions are made and so on.

    Comment by Anonymous Coward — 11 Apr 2010 @ 6:39 PM

  145. Eric: Google finds (if I can paste the working search string, let’s see)
    http://www.google.com/search?hl=en&q=%22warming+per+unit+CO2+emitted%22

    what’s probably the same text as the published paper:
    http://www.cccma.ec.gc.ca/papers/ngillett/PDFS/nature08047.pdf

    They’re talking about the ‘global warming potential’ of CO2 over time compared to other molecules, and how that’s affected over time (in ways different for CO2 than other molecules) by band-filling (radiation physics) and by ocean solution (physical chemistry) of that particular molecule.

    This isn’t about temperature.

    That claim is cited to their fn2:
    2. Caldeira, K. & Kasting, J. F. Insensitivity of global warming potentials to carbon dioxide emissions scenarios. Nature 366, 251–253 (1993).

    The abstract of that paper says in part:

    “… for non-steady-state conditions, the integrated climate forcing from a CO2 perturbation depends both on the initial conditions and on future atmospheric CO2 concentrations. As atmospheric CO2 concentrations increase, the radiative forcing per unit CO2 emitted will become smaller because the strongest absorption bands will already be saturated. At the same time, higher concentrations of dissolved carbon in the surface ocean will reduce the ocean’s ability to absorb excess CO2 from the atmosphere. Each of these effects taken alone would affect the climate forcing from a pulse of emitted CO2 by a factor of three or more; but here we show that, taken together, they compensate for each other. The net result is that the global warming potential of CO2 relative to other radiatively active trace gases is nearly independent of the CO2 emission scenario. Thus, the concept of the global warming potential remains useful, despite the nonlinearities in the climate system and uncertainties in future emissions.”

    —–
    Please correct me if I’ve misread this; I’m just reading and moving my lips.

    Comment by Hank Roberts — 11 Apr 2010 @ 8:24 PM

  146. Hank #143

    You mean ocean pH is dropping very fast, not increasing, right? was 8.3, is now 8.0-7.9; on a log scale, this is a huge change.

    Comment by Denys F Leclerc — 11 Apr 2010 @ 9:42 PM

  147. re: 146

    A pH of 7.9 is predicted by the end of the century.

    Comment by Jeffrey Davis — 12 Apr 2010 @ 8:49 AM

  148. Re #133 William and response by eric,

    It seems like there is a failure in the discussion process where sea surface temperature is confused with ocean heat content. Ocean heat content is of course an integral of temperature over depth, and of course the surface temperature might not go up much while deeper temperatures do.

    To say that there is more sea ice lost as an explanation of sea level rise is an inadequately supported conclusion.

    Back a few months ago we had a chart from NOAA showing a very significant increase in ocean heat content (measured only down to 700 meters) along with a suggestion of a plateau in global surface temperatures. (As I understand the climate modelers boundary conditions, global surface temperatures are the same as ocean surface temperatures, and the top “mixed layer” rapidly adjusts to that same value.)

    My sense of things is that there is something wrong with the way the “mixed layer” is used to characterize vertical mixing of heat into the ocean. It looks like the ocean agrees with me, as represented by the actual NOAA data on heat content.

    I have to acknowledge that I can not keep up with it all, but I have not found an analysis that relates NOAA heat content data to sea level rise. This would be a meaningful basis on which to discuss why sea level rise numbers are what they are.

    Comment by Jim Bullis, Miastrada Co. — 12 Apr 2010 @ 1:57 PM

  149. @Martin (or Stefan):

    Any interest in defending your paper @klimazwiebel? It seems there is some valid, but also markedly less valid discussion going on there:
    http://klimazwiebel.blogspot.com/2010/04/sea-level-rice.html

    Comment by Marco — 12 Apr 2010 @ 2:04 PM

  150. Dear Martin and Stefan,

    somehow I keep wondering about the difference between the here used smoothed data and the data from Holgate 2007)
    It seems to me that for example if you would add the measured unsmoothed “Rate of sea level change” in the very first diagram of yours,
    that there are periods where the measured data (including error bars) is far outside the range which is the basis of your calculations (for example around 1980 the rate drops below zero including error bars)
    Are you aware, that oversmoothed data produces wrong trends.

    All the best,
    LoN

    Comment by Laws of Nature — 13 Apr 2010 @ 1:13 AM

  151. G. the warmer : “The scenario you linked to in #128 is one such scenario but it’s not realistic.
    A halfway-realistic scenario in which temperatures decrease soon enough to mitigate a large SLR would in my opinion involve a combination of the following:
    1) emissions reductions
    2) CO2 sequestration
    3) geoengineering
    I don’t think one of these on its own would realistically be enough with current technology unless perhaps extreme measures are taken. For instance I don’t think emissions can be reduced to anywhere close to zero in the forseeable future.”

    I regret you don’t give any quantitative estimates : in this topics, everything is a question of numbers. Could you give an example of which temperature decrease could be reached , with which amount of GtC burnt/sequestrated , and which limit (quantitatively) on the SLR we could hope to stay within in the next centuries, if Stefan and Martin are correct ?

    Comment by Gilles — 14 Apr 2010 @ 12:51 AM

  152. Martin,

    A fascinating post for lots of reasons. It seems to me that introducing your second term b.dT/dt into the equation is a step forward.

    However, I don’t believe b is negative in the real world. This would imply a sudden sea-level rise of several mm following a cooling event, such as one caused by a volcanic eruption, which is not observed.

    I suspect a problem with your water storage adjustment based on Chao et al. My initial impression, reinforced by having looked into the topic in a little more detail since you posted (see see the entry on my own blog), is that the water storage behind dams quantified in Chao et al is exceeded in magnitude by the combined effects of ground water pumping, land-use change and over-exploitation of surface water resources. The Aral Sea alone (not even including the water table in the surrounding region) lost around 1000km3 from the 1960s to c.2000, nearly 10% of the Chao et al estimate for total water storage. Fred Pearce’s book When the rivers run dry is a good read about water use (though annoyingly includes no references).

    I suspect that statistically the problem occurs over the period from the 1940s to the 1970s when temperatures were flat or declining slightly. Clearly, b has to explain most of the variation in the rate of sea-level change when temperatures are fluctuating around a constant level, as over this period. Over the rest of the instrumental record, sea-level is rising (at least when smoothed), and a and b can be adjusted to fit the data.

    In the real world, the rate of sea-level rise must have been declining from the 1940s to the 1970s (e.g. see the slowing rate of retreat of glaciers in IPCC Fig 4.14). Your water storage adjustment appears to produce an increase in the rate from the early 1960s. If this did not in fact occur, it seems to me that your method of determining b by the best fit to the data might well lead to an erroneous result.

    To establish b more accurately would need a global inventory of all water stores including those in ecosystems such as wetlands and forests (as Pearce notes, most water is held in soils) not just those included in Chao et al.

    It also occurs to me, though, that, while we’re preparing the full water inventory, it might be possible to establish b by use of the fact that it explains more variation than parameter a the shorter the time scale (Fig 3 in the Vermeer & Rahmstorf paper shows a lot of smoothing), though the approach would be less textbook and more back of envelope. The fit would not be highly significant because of noise in the data, but the best fit to the annual data and that smoothed over a small number of years would surely give the best approximation to b (you could increase the years of smoothing until b becomes stable). This could then be applied to the smoothed data, the best fit to that giving a good approximation to parameter a (which I suppose would have to be fed recursively into the analysis of the less smoothed data) and telling us something about the accuracy of the water storage adjustment.

    Comment by Tim Joslin — 14 Apr 2010 @ 5:33 AM

  153. Hank (#145),

    Thanks for the link. But, the way I read them, the letters are indeed about temperatures. The thing is, the more I look into it the more I find the Matthews letter unserious.

    The Caldeira & Kalding paper it cites doesn’t show what is claimed. It doesn’t explain how its ocean and CO2 flux model works (are SSTs even considered as a factor in the flux?) and I wouldn’t give it too much weight but in any case it simply doesn’t support his case. It has two unrealistic BAU-looking scenarios simulated and graphed for instance. Eyeballing them I see one emissions path peaking at 80% more GtC/year than the second but atmospheric CO2 peaks at only 15% more. Obviously 80% more emissions didn’t result in anything like 80% more forcing early on. As to the longer term, the forcing from the emissions paths (which have the same amount of carbon emitted over time) converge only 150-250 years after the fast emissions peak with this relatively simple model.
    None of this is unexpected I think but it doesn’t support Matthews’ contrarian claims. The claims are verified when you get closer to equilibrium but that’s long after the forcing has peaked and, so far as I can tell, the model does not have slow feedbacks such as permafrost or ice sheets melt which would put the fast emissions scenarios on a path to higher temperatures and higher CO2 concentrations due to the higher temperatures during the first two or three centuries.
    As far as I can determine, the one case that’s legitimately made in these letters is a case against delaying emissions cuts (loading the oceanic CO2 sink has a long-term cost essentially). But, while Matthews’ cavalier statements could also be used to argue against emissions cuts, I don’t think the output of these models could legitimately be used that way (nevermind their lack of realism).

    I won’t rant endlessly about Matthews’ letter but there’s one thing I need to say. We have discussed how his recent claim that there is no global warming commitment is presposterous, in part because it ignores aerosols. But look at his justification for ignoring aerosols this time (in the mehodology section): “Our calculation also assumes that climate forcings other than CO2 emissions have had little influence on atmospheric CO2 concentration. This is a reasonable assumption given a near-cancellation over the past century of positive non-CO2 greenhouse-gas forcing and negative aerosol forcing.” This in the context of 1000-year simulations. The mind boggles. This assumption is going to work out great with methane after emissions finally drop (whether it be because of policy or depletion)!

    Comment by Anonymous Coward — 14 Apr 2010 @ 9:29 AM

  154. Gilles (#151),

    I’m sorry but there is too much uncertainty over the long-term impacts for a non-specia_list to kid around with numbers like this.
    But feel free to combine Matthews (which makes everything so much simpler) with Rahmstorf & Vermeer: Feed 0.0017 centigrade multiplied by net GtC emitted (after substracting GtC sequestrated that is) into their SLR model. I wouldn’t give much weight to the result but you’d have numbers, and numbers based on the litterature instead of my musings to boot!
    When it comes to “the next centuries”, the biggest uncertainty is future social and technological development anyway. I think we can agree about that.

    I think the one number worth repeating is 350. Unlike GtC and the like, this number doesn’t hang on assumptions and modelling.

    Comment by Anonymous Coward — 14 Apr 2010 @ 9:54 AM

  155. AC “Gilles (#154),
    I’m sorry but there is too much uncertainty over the long-term impacts for a non-specia_list to kid around with numbers like this.”

    I don’t think that multiplying a derivative by a relaxation time to get an order of magnitude of the global variation is exceptionally tough, nor that it requires to be a “specia_list” of the domain, since it involves only basic properties of rather simple differential equations. If this is your only argument to contradict mine, I’m afraid I wouldn’t consider that you could bring much information to me – which doesn’t imply any other personal judgement about you, of course.

    Comment by Gilles — 14 Apr 2010 @ 11:21 AM

  156. Don’t be silly, Gilles: you know you need the temperature curve over the next two centuries to get the SLR. Obviously the uncertainties I was talking about regarding the climate concerns how you get from GtC to temperatures.

    You have presented no “argument” by the way.

    Comment by Anonymous Coward — 14 Apr 2010 @ 2:07 PM

  157. if the equations of Stefan and Martin are correct (implying dL/dt >= a (T-To) ) , obviously one only needs a lower limit on the temperature to get a lower limit on the SLR. So which lower limit of the warming do you consider as reasonable for the coming centuries, for reasonable hypothesis of fossil fuels consumption ?

    Comment by Gilles — 14 Apr 2010 @ 4:17 PM

  158. Tim Joslin #152,

    thank you for your interesting thoughts.

    However, I don’t believe b is negative in the real world. This would imply a sudden sea-level rise of several mm following a cooling event, such as one caused by a volcanic eruption, which is not observed.

    Actually, not quite true… see Grinsted at al. 2007. More relevantly perhaps, if the apparently negative b is related to a time delay as we suspect, your argument doesn’t apply either.

    About the ground water (aquifer) extraction, yes, this is probably of similar order of magnitude as the reservoir storage. However, it is not just the magnitude that matters; it is also the shape of the curve as a function of time, and the shape of the reservoir correction is very special. It leads to the quality of fit becoming very much poorer when it is not applied.

    What the shape of the curve of ground water extraction is, we can only guess; it could be such that the quality of fit is unaffected and the correction is absorbed into the estimated parameters — and yes, that could mean that b becomes less negative. We just don’t know at this point. For the three test functions we used in the SI (Table S1), what happened was that indeed the quality of fit was almost unaffected, and the correction was absorbed into the estimated coefficients, mostly a.

    The problem with your final proposal is the natural-variability noise in the data, which blows up if you take the smoothing time much below 15 years. We looked at that a bit, and are weary of trying to extract more information from the sea level data than is there… we would really need a good, independent ground water inventory.

    Comment by Martin Vermeer — 15 Apr 2010 @ 1:16 AM

  159. Gilles,
    I’m not following you. If you do not make any other assumption or hypothesis than “reasonable” fossil fuels consumption, pretty much everything is possible over 200 years. I suppose a lower limit would be -0.5 centigrade (that is half a degree of cooling). I figure there’s no reason to aim lower than -0.35 and I round it down in case a future geoengineering program overshoots a bit. I don’t believe such an outcome is likely but I can’t rule it out either. It is becoming less likely every year however.

    Comment by Anonymous Coward — 15 Apr 2010 @ 4:41 AM

  160. “Gilles,
    I’m not following you. If you do not make any other assumption or hypothesis than “reasonable” fossil fuels consumption, pretty much everything is possible over 200 years. I suppose a lower limit would be -0.5 centigrade (that is half a degree of cooling). ”

    But when you say “I suppose”, is it only wishful thinking, or do you have a real agenda to reach that ? we hear interesting things here !

    Comment by Gilles — 15 Apr 2010 @ 11:58 PM

  161. > and are weary of trying to extract

    Wary, actually ;-)

    Comment by Martin Vermeer — 16 Apr 2010 @ 12:54 AM

  162. When I wrote “I suppose”, I meant “I figure there’s no reason to aim lower”. More cooling could in principle be acheived through geoengineering.
    It’s not “wishful thinking” nor my “agenda”: it’s futurology. Two centuries is a long time.
    While I would tend to support politicians willing to fund research in carbon sequestration and geoengineering, my agenda, based on what can actually be done here and now, is Hansen’s: opposing coal and unconventional oil at every turn, deep emissions cuts through fee & dividend and pilot biomass burial programs. The target I’m proposing for the next century is 350, which would probably not deliver cooling or a stable sea level. Future generations will take up that challenge if they choose to.

    Comment by Anonymous Coward — 16 Apr 2010 @ 11:15 AM

  163. “161
    Martin Vermeer says:
    16 April 2010 at 12:54 AM

    > and are weary of trying to extract

    Wary, actually ;-)”

    I prefer the first one…

    Comment by Completely Fed Up — 16 Apr 2010 @ 11:24 AM

  164. @AC, Eric: I am afraid the discussion about Matthews here is partly too complicated for the likes of me.
    I had not realised that Matthews (2009) was controversial. Are you saying, essentially, that the conventional position is that emissions trajectory is a more important determiner of temperature outcomes than total cumulative carbon emissions? (The point I had wanted to make with citing Matttews was simply what’s in the title of the paper: global warming will be proportional to cumulative emissions, which I thought had been contested earlier.) Certainly I had not wanted to say that there won’t be ocean acidification or additiolnal effects on the biosphere (this is simply not what the paper is about.)
    I was a bit surprised/confused by the reaction because it’s not that unsusual to see total emissions targets mentioned in climate change discussions. I had not been aware that that position is “contrarian”. The Matthews paper wasn’t reported as contrarian in the press. (The BBC reported it as giving politicians easy-to handle numbers to use for planning emission cuts) Also, there is another paper that Matthew co-wrote with K. Caldeira, who to my knowledge isn’t a contrarian. That paper, “Stabilizing climate requires near-zero emissions”, 2008, is also relevant to the point I had originally wanted to make, eg: we do have to cut to zero sometime in the second half of this or early in the next century if we want to stabilize climate at or below two degrees. If Matthew’s premises are right, it is not enough to reduce global yearly emissions by half (or some such number) to stabilize climate at or below two degrees. THis would only postpone the moment when we have to wean ourselves completely from fossil fuels for a few decades. So if Matthews is right, it really is a choice between reaping the benefits of fossil fuels and take the consequences, or doing without them and avoiding some consequences (not all, because it will already be to late for some.) I had understood Gilles to be saying something like that.
    If all of this is doubtful/controversial, please give me some legit sources that enlighten me.
    What I do see is that Matthews disagrees with Plattner on the question whether there is a warming commitment. I myself, with my layperson’s understanding, find Matthews’ assumption that there is practically no commitment improbable, as albedo feedbacks from melting and reduced snow cover should intensify for a while even after an emissions stop, and as the drop in aersols (no more coal) should result in some more warming as well; although clearly Matthews must have some of these factored in because unless for feedbacks the temperature should begin to fall immmediately after a stop in emissions and it doesn’t in his models. (see his other paper on climate change commitment).
    But certainly if there is commitment it just strengthens Gilles’ position (as I understood him) that we realistically can’t stop sea level rise for the next few centuries even with strong mitigation.
    Maybe someone from the RCteam could help here. And in your replies, please remember: I am an environmentally interested, scientifically literate layperson, not a climate speciali st.

    Comment by C. Streif — 16 Apr 2010 @ 11:25 AM

  165. “But certainly if there is commitment it just strengthens Gilles’ position (as I understood him) that we realistically can’t stop sea level rise for the next few centuries even with strong mitigation”

    So if we can’t, which is better:

    Year X 1m rise
    Year X+Y 2m rise
    Year X+2Y 3m rise

    Year X+30Y 31m rise
    OR
    Year X 1m rise
    Year X+Y 2m rise
    Year X+2Y 4m rise

    Year X+30Y lots m rise

    ?

    Comment by Completely Fed Up — 16 Apr 2010 @ 3:06 PM

  166. Completely Fed Up (165) — The rise will be S-shaped and the maximum pssible is about 80 meters.

    Comment by David B. Benson — 16 Apr 2010 @ 4:18 PM

  167. Dai, if we keep increasing CO2 concentrations, we get a higher and quicker rising S curve than if we stopped.

    This was the illustration.

    Comment by Completely Fed Up — 16 Apr 2010 @ 4:31 PM

  168. PS technically, if we raise temps enough, then for gassy enough definitions of “water”, our water level will be over 11km high.

    But some would say this is good: look at the lovely steam baths the Swedish enjoy!

    Comment by Completely Fed Up — 16 Apr 2010 @ 4:32 PM

  169. C. Streif (#164),

    I’m not saying that the “emissions trajectory is a more important determiner of temperature outcome than total cumulative carbon emissions”. I’m saying that slowing emissions so as to limit atmospheric concentrations over the whole period would result in less warming than if the same amount of carbon was emitted faster, especially if slow feedbacks are considered. Please refer to the references I’ve already given (IPCC AR4, Hansen’s “Target CO2″ paper).
    The main reason why emissions should be slowed has little to do with climatology anyway. Slower emissions opens the opportunity for more drastic cuts at a later date and therefore lower cumulative emissions should that be deemed necessary. Also, years of R&D will be needed before serious sequestration programs could be started (if they’re ever started) and geoengineering would at best be even slower to jumpstart. Such programs would have the most impact around the peak of the temperature curve and fast emissions shift the peak closer to the present.

    Gilles used the “total emissions” concept to argue against emissions cuts (see post #108). In my opinion, he’s not abusing a useful policy tool. He’s only stating explicitely the politically incorrect reason why this policy metric is being pushed. Recall that most wealthy countries have already failed to meet their Kyoto emissions rates. This “total emissions” business can be used as yet another delaying tactic: we’ll cut more later and we’ll meet the target just as well as if we cut now. Matthews’ simplification of the science is evidently politically motivated and it’s not surprising it’s popular.

    Even if Matthews’ climatology was right, cutting emissions to zero is not necessary to acheive any reasonable target. The paper you’re talking about uses the phrase “near-zero emissions” which is not the same thing. Consumption could obviously be prolonged for an arbitrary amount of time (not just decades) with the right decline rate. Since it’s easy to come up with valuable applications for fossil fuels for which there is no efficient substitute on the horizon, you’re granting ready-made arguments to the delayers by insisting on zero emissions.
    And since sequestration compensates for burning fossil fuels, I would also encourage you to use the phrase “net emissions” so as to allow for continued use of fossil fuels on a large scale if needed. It may also be worth pointing out that cutting on frivolous uses over the next decades would preserve the limited resource for truely valuable applications in the future, over centuries if needed.

    As to the sea level, I think we all agree that mitigation alone can not realistically stop its rise, only the acceleration of its rise.

    Comment by Anonymous Coward — 16 Apr 2010 @ 5:22 PM

  170. ““But certainly if there is commitment it just strengthens Gilles’ position (as I understood him) that we realistically can’t stop sea level rise for the next few centuries even with strong mitigation”

    So if we can’t, which is better:”

    well, if limiting FF use has strictly no inconvenience, the answer is obvious. If it is the case, we should stop them immediately. Which “nobody advocates” (that’s the usual reply). So if nobody advocates it, it means that stopping FF HAS some inconvenience. So the answer to your question is not obvious. It’s a question of balance. Knowing that the sea level rise is unavoidable, and that all constructions and artifacts of civilization have a finite lifetime, it demands some precise comparison between the real cost of diminishing FF and the real marginal cost of increasing the SLR during an average lifetime of what could be threatened. I don’t have the answer, you probably don’t have it, and nobody has it either. Not a good starting point to convince people.

    Comment by Gilles — 16 Apr 2010 @ 6:04 PM

  171. AC ;:”When I wrote “I suppose”, I meant “I figure there’s no reason to aim lower”. More cooling could in principle be acheived through geoengineering.
    It’s not “wishful thinking” nor my “agenda”: it’s futurology. Two centuries is a long time.”

    AC, I have nothing against futurology, but please do it in a coherent way. If we find a way of strongly reducing the CO2 concentration and inverting the temperature curve, it would also mean that CO2 is no more a problem. Hence that we shouldn’t worry too much about what we burn now. So again I don’t see a clear case where we could change the future by acting on our current consumption. Either we can’t stop the SLR below a few meters and we won’t be able to stop it anyway – or we find a way of stopping it and it will work anyway. In no hypothesis would the future of SLR strongly depend of our FF consumption in the next decades :this is not the relevant parameter.

    Comment by Gilles — 17 Apr 2010 @ 1:17 AM

  172. Gilles (171),

    If we find a way of strongly reducing the CO2 concentration and inverting the temperature curve, it would also mean that CO2 is no more a problem. Hence that we shouldn’t worry too much about what we burn now.

    BPL: Your “[h]ence” is a non sequitur.

    1. We don’t know of any such method. It may take 100 years for one to come along. That would be too late. The climate would already be wrecked, along with human civilization.

    2. We may be close to tripping the geophysical feedbacks (e.g. melting clathrates) that will make the problem impossible to fix. The time to reduce CO2 emissions is NOW. Not some unspecified future date. Hope is nice, but stupidity is counterproductive.

    Comment by Barton Paul Levenson — 17 Apr 2010 @ 4:45 AM

  173. “So again I don’t see a clear case where we could change the future by acting on our current consumption.”

    Here’es one, oh blind master:

    If we don’t consume so much now, it will not have been consumed now in the future. This means we don’t have to undo that consumption.

    You never acted like this when you “passed” your degree, did you, ‘cos this sort of “thinking” would have you chucked out.

    Comment by Completely Fed Up — 17 Apr 2010 @ 6:44 AM

  174. “So if nobody advocates it, it means that stopping FF HAS some inconvenience. ”

    And if continuing FF use has some inconvenience, then this must mean we MUST STOP NOW.

    In your binary world, anyway.

    Or please show me that there is no inconvenience with using fossil fuels.

    Hint: Exxon Valdes.

    Comment by Completely Fed Up — 17 Apr 2010 @ 6:46 AM

  175. BPL (#172).

    Strictly speaking, no “methods” would be needed. CO2 atmospheric concentration would drop without intervention (unless nasty feedbacks are triggered) and most AR4 models have temperature falling slowly without intervention as well (though they may be badly wrong).

    Some methods such as loading the stratosphere with sulfate aerosols are known to affect the climate although no efficient implementation has been devised yet. On the other hand, many biomass sequestration methods have been implemented on a scall scale and there is no reason to believe they wouldn’t affect the climate on a large scale. Though CCS coal plants are controversial, even inefficient CCS would be carbon negative in combination with biogas for instance. And so on…
    None of this amounts to a ready-made, scalable and efficient climate management program of course and there may well be better methods which are unproven or totally unknown but it’s not accurate to state that “we don’t know of any such method”. If you want a reference, Hansen et al. briefly outlines some methods in the “Target CO2″ paper for instance.

    Comment by Anonymous Coward — 17 Apr 2010 @ 8:42 AM

  176. CFU:”“So if nobody advocates it, it means that stopping FF HAS some inconvenience. ”

    And if continuing FF use has some inconvenience, then this must mean we MUST STOP NOW.

    In your binary world, anyway.

    Or please show me that there is no inconvenience with using fossil fuels.

    Hint: Exxon Valdes.”
    CFU, show me something without any inconvenience. Even eating can produce diseases. So stop eating.

    I have no binary world : YOUR world is binary (fossil fuels are evil, stopping them is good). My world is complex, and I humbly recognize that I don’t know enough to tell mankind what to do. I admire you so much to know so perfectly what it should…

    Comment by Gilles — 17 Apr 2010 @ 10:36 AM

  177. “BPL: Your “[h]ence” is a non sequitur.

    1. We don’t know of any such method. It may take 100 years for one to come along. That would be too late. The climate would already be wrecked, along with human civilization.

    BPL, we focus here on the problem of sea level rise. Please don’t make me explain again everything from the beginning !

    Comment by Gilles — 17 Apr 2010 @ 10:37 AM

  178. #107 Philip Machanick says:
    9 April 2010 at 6:16 AM

    “Waqidi Falicoff #66: Maunder minimum? Tell your buddy to check out the latest satellite AMSU-A data as explained at my blog.

    As to your direct question, why is it reasonable (as in the blog you refer to) to set dH/dt to a constant? Note that the author’s logic requires a temperature trend growing as exp(-at/b). This is a growth rate that rapidly converges to zero, unless you reverse the sign by making one of the multiplied constants (a or b) negative. Big surprise: it results in constant sea level rise when you plug it into the equation given in the paper covered here. Oh and the author fibs slightly about using the same constants as in the paper in his own calculations. In the paper, b = 2.5″

    and

    # 120 Waqidi Falicoff says:
    9 April 2010 at 2:35 PM

    “To 90 (Efs_Junior) and 107 (Philip) Thanks for your comments. I have passed them on to my colleague.”

    #121 Philip Machanick says:
    9 April 2010 at 3:50 PM

    “Waqidi Falicoff 120: my comments got snipped partway through for some reason. This is a small fraction of the problems in the article you referred to. Your colleague should download the spreadsheet if he (or she) has any numeracy at all and will find that the whole thing is a total fraud: the formulae for the graphs on the site bear no relationship to the calculations in the spreadsheet.”

    By all means download the spreadsheet(s).

    Upon further investigation the integration will be correct for SLR and SLR if you use a very small dt ~ 0.0001 years, but still the assumed temperature curves are ad hoc, and produce ludicrous values for temperature before even the end of the 20th century.

    But the ad hoc temperature curves really don’t do anything if you look at the spreadsheet(s) and their value for gamma (there are now 5 parts at climatesanity, but I’m just discussing the first three parts) is equal to one, this means that the first term of their eq 4 (with gamma = one as per the spreadsheets);

    http://climatesanity.wordpress.com/2010/03/27/rahmstorf-2009-off-the-mark-again-part-2/

    is (1 – gamma) * and desired temperature profile (temperature profile doesn’t matter as (1 – gamma) = (1 – 1) = 0!

    Also the backward finite difference isn’t calculated correctly (small error introduced), they should use a central diffenence with any 3- 5- 7- or 9-point stencel.

    I used a 9-point stencel with dt = one year (same as spreadsheets), but you don’t need to do this. Just calculate a*(Toffset – To) to arrive at the annual SLR slope per year.

    D’oh!

    I have a much better Excel spreadsheet than ClimateSanity has (tou’ll just have to trust me on this or I can send you a copy).

    I’m now off to shoot down Parts 4 & 5 & however many parts that ClimateSanity choose to throw up.

    Also since the assumed equation is deterministic, it is directly integrable without the need to use numerical finite differences (just a restatement from my previous post).

    Comment by EFS_Junior — 17 Apr 2010 @ 12:19 PM

  179. #107 Philip Machanick says:
    9 April 2010 at 6:16 AM

    “In the paper, b = 2.5″

    No.

    b = 2.5 is obtaied in the section titled;

    Testing the Dual Model on Simulated Future Sea-Level Rise.

    which ClimateSanity does not use, what ClimateSanity does use are from the actual (smoothed) sea level record (“For sea level we use the data of Church and White (18) as adopted by the IPCC.”) from the V&R (2009) section;

    Testing the Dual Model on Observed Data.

    “The parameter values obtained are To = -0.41 +/- 0.03 K, a = 0.56 +/ 0.05 cm/(a * K), and b = -4.9 +/ 1.0 cm/K.”

    NOTE: ClimateSanity (parts 4 and 5) are GIGO, the ad hoc curves they assume are not continuous with the prior time series of actual temperature data (in FEA this is called C0, C1, C2, C* continuity across element boundaries), the ad hoc temperature curves jump suddenly from the prior smoothed temperature time series (technically these ad hoc curves don’t even pass the C0 continuity test).

    For example, I’ve fitted exponential curves to the entire C&H (2006) raw data that produce total temperature rises of 2, 4, and 6 degrees C in 2100 AD. Using the same constants from V&R (2009) and get very reasonable SLR and SLRR in 2100 AD (similar, but not the same as V&R (2009)).

    Comment by EFS_Junior — 17 Apr 2010 @ 1:21 PM

  180. Gilles (177): BPL, we focus here on the problem of sea level rise. Please don’t make me explain again everything from the beginning !

    BPL: And I’m pointing out that sea-level rise is a long-term problem, whereas drought is here and now and getting worse. Il faut manger.

    Comment by Barton Paul Levenson — 18 Apr 2010 @ 5:59 AM

  181. BPL : OK, we’ll discuss that on the next thread about droughts ! I think we have a problem anyway with the demographic growth, independently of CO2 concentration. Here again depletion of fossil fuels, and increasing prices of gasoline and fertilizers, will probably be the most crucial problem in the next future.

    Comment by Gilles — 18 Apr 2010 @ 10:44 AM

  182. “CFU, show me something without any inconvenience. ”

    That was rather my point.

    You dismiss renewables because they have an inconvenience:

    #170 “So if nobody advocates it, it means that stopping FF HAS some inconvenience”

    But now it’s all “well, EVERYTHING has inconvenience”.

    So how does FF inconvenience draw us to any conclusion.

    You don’t listen to a word you say, do you.

    Comment by Completely Fed Up — 18 Apr 2010 @ 4:35 PM

  183. CFU : I don’t see your point. Everything has inconvenience, and things have also more or less advantages. The only inconvenience of renewables is that they can simply not support by themselves the industrial society. It’s not an inconvenience, it more a disability. That’s physics, how can you change it ?

    Comment by Gilles — 18 Apr 2010 @ 5:48 PM

  184. “CFU : I don’t see your point. Everything has inconvenience, and things have also more or less advantages”

    Which you “forgot” when talking about the inconvenience of leaving fossil fuels.

    How inconvenient.

    “The only inconvenience of renewables is that they can simply not support by themselves the industrial society.”

    You keep repeating this canard but it’s completely unsupported and false.

    “That’s physics, how can you change it ?”

    No, that’s complete made up bollocks, and you won’t change it to reflect reality.

    Comment by Completely Fed Up — 19 Apr 2010 @ 3:06 AM

  185. AC (#169):
    Dear AC, I certainly see eye to eye with you on immediate action (because reduction will have to be gradual to be practicable) and on avoiding frivolous use NOW. (I have done so for a long time, my yearly emissions according to the Greenpeace calculator: 4,5 tons.) And by the way I for one live in a country (Germany) that has met its Kyoto targets.
    But with a long-lived gas like CO2, what I don’t see is how stabilization can be reached without getting down to zero emissions (from fuel combustion) for at least a few centuries, unless of course one uses large-scale sequestration, but then again, carbon caption and storage is not a proven technology at this point in time , even less so than nuclear fusion (which I am not waiting for to solve the climate problem, or are you?). The “proven” alternatives (like reforestation) yield far too little sequestration to make a meaningful difference. (Unless you use more arable land than the earth possesses.)
    I have cited Matthews to make the point that total emissions are what counts, there is also this: http://www.nature.com/nature/journal/v458/n7242/full/nature08019.html , saying that “the relationship between cumulative emissions and peak warming is remarkably insensitive to emissions pathway (timing of emissions or peak emissions rate).” See also this http://www.nature.com/nature/journal/v458/n7242/full/nature08017.html which also usees cumulative emissions to calculate climate effects (from Stefan’s institute, so please don’t tell me it’s contrarian or “politically motivated”).
    To support your argument that we won’t have to cut as radically if we cut soon, you refer me to AR4 (what chapter?) and “Hansen’s target CO2″ paper. I recently read the Hansen paper. If I remember rightly, Hansen (2008 or 2009) argues that we should stabilize at 350 ppm.
    Now accepting 350 as target CO2, let’s do a calculation. Current emissions (2004, Wikipedia) are in the range of 27 gigatons CO2 (=. 7,4 Gigatons C) which translate to a rise of ca. 2 ppm per year, more than double what it was in the sixties. The percentage taken up by the biosphere has so far stayed largely constant with rising emissions, so even with sinking emissions there will always be a percentage that stays in the air. One older Hansen paper (which I took a few notes from at the time) assumes a more or less constant if (to my mind) a bit high relationship of 2,1 Gigatons C giving a rise of 1 ppm CO2.
    So if even a massive cut of more than two thirds (from over 7 Gigatons down to 2,1) still gives us a yearly rise of one (or more probably 0.6) ppm, how do we get back to 350 ppm and climate stabilization without fuel emissions per capita cut back almost to nil? Remember, we will soon have a population of 9 billion whith a rising living standard who will engender lots more land use change and methane and co2 from cement even if they don’t use more fossil fuels.
    Rereading the 2009 (Target CO2) Hansen paper now, I find it actually supports my argument. Hansen says: “Stabilizing atmospheric CO2 and climate requires that net CO2 emissions approach zero”.
    That was my point all along. See also further down: “Thus, moderate delay of fossil fuel use wil not appreciably reduce long-term human-made climate change. Preservation of a climate resembling that to which humanity is accumstomed will require that most remaining fossil fuel carbon is never emitted.”

    Comment by C. Streif — 19 Apr 2010 @ 6:24 AM

  186. Gilles, #183: What you say is true for biomass (which, unless it’s waste biomass, nobody in their senses advocates any more). Or do you mean the storage problem with wind an solar? That is certainly solvable, only at the moment storage is a bit expensive; also, using a large grid that has for eample wind from the french atlantic coast as well as from the ukraine, and solar from morocco as well as turkey, will reduce the storage needs . I have not seen a single study that says that wind and solar combined can’t run an industrialized economy according to “physics”. On the contrary, the German physical society supports solar power generation in the sahara. The problem is that it’s expensive, and thatb redesigning the infrastructure for a complete switch is also very expensive (and it does use more land than nuclear or fossil). So one would have to do the switch over several generations. And presumably countries were people are still dying because of malnutrition and that have lotsb of cheap coal don’t havge enough incentives to switch because possible future benefits of mitigation don’t outweigh its present drawbacks.

    Comment by C. Streif — 19 Apr 2010 @ 6:36 AM

  187. “And presumably countries were people are still dying because of malnutrition and that have lotsb of cheap coal”

    And they are dying despite cheap coal. They are also the least likely to be able to survive changes in the climate. Being poor is better than being dead.

    Also consider that they don’t have invested capital in the old technology: mobile phone penetration in Africa beats many “first world” countries (including the USA) because they don’t have lots of copper wires and so rollout of wireless access is cheaper than buying and laying copper.

    Comment by Completely Fed Up — 19 Apr 2010 @ 9:31 AM

  188. C. Streif (#185),

    Regarding zero emissions, I think my point is obvious but I will elaborate: even if only the total cumulative emissions mattered (which is clearly not the case), it does not follow that emissions need to be brought down to zero to limit this total. 50 years at 100% of a baseline emission rate gives you the same total amount as 100 years at 50% or 80 years at 40% followed by 360 years at 5%.
    Hansen indeed says “requires that net emissions approach zero”. This is not the same thing as bringing net emissions to zero and certainly not the same thing as stoppoing to use fossil fuels (recall the “net” part). Note also that I’m not talking about a “moderate” delay in fossil fuel use: I’m talking about delaying it so as to minimize the atmospheric fraction which requires delaying it to a significant fraction of the timescale of CO2 diffusion in the oceans (about 1000 years).

    It seems we also have different socio-economic assumptions. I do not believe that a 9 billion population with rising material standards of living is likely. Nor do I believe that a two-thirds emissions cut would be particulary “massive” or challenging over several decades.
    The big Saudi oil fields are not representative of the fossil fuel reserve. Much of the reserve is nearly useless, unstable and/or hard to get, small desposits that are hard or impossible to exploit economically and so on. I believe most of the resource is likely to stay in the ground irrespective of policy. I also believe the quality, easily accessed stuff will be burned sooner or later. This also informs my opinions about appropriate policies which is why I believe coal needs to be the main target and that Germany should therefore not be held up as an example.
    It’s not any kind of achievement to meet Kyoto targets when the FDR uses the DDR’s quota. In my opinion, there’s a streak of denial and flight to fantasy in Germany with regards to electricity issues. The comparison with France is striking.

    Humanity has sequestered carbon since ancient times and fossil fuels are the product of geologically ancient carbon as well. Biochar was famously used by amerindians for instance. Carbon sequestration through photosynthesis is well understood. Reforestation is not sequestration.
    CCS is proven too, contrary to your assertion. Check the Wikipedia or something. Anyone not ideologically motivated to the point of blindness can see that. If you’re being honest, you need to upgrade your skepticism and to reconsider your choice of sources.
    Frankly, I find it rich to claim that sequestration methods are not proven in order to propose a fantasy as an alternative. Technically and socially, nobody knows how to do reduce fossil fuel consumption to zero. Fossil fuel have no proven and scalabe substitutes for many valuable applications. Sequestration is realistic in comparison.

    You quote Matthews but it’s not clear you’ve understood the argument. The flux of CO2 to the oceans (the biospehere is more complicated) is a function of atmospheric concentration and not of emissions as such. Matthews’ whole point is that the more carbon is emitted, the larger the share that’s going to remain airborne. The reverse is also true. Barring nasty feedbacks, there is therefore an emissions rate at which the atmospheric concentration falls and that’s not even close to zero as you imply.

    Again, I would recommend against quoting papers and especially abstracts in this fashion. I did the same thing for kicks with the Matthews paper and Eric went “?!?”. You need to look at the context carefully. Usually these kind of statements are only true in particular conditions and so on. Words like “remarkably” are also meaningless while the models’ output is quite eloquent if presented well and doesn’t necessarily support the spin that’s put on it.
    I think it’s also obvious that a paper talking about 2C, the G8, policies and so on is politically motivated. Hansen is politically motivated too of course… only I like his politics.
    But when the paper you reference says that a cumulative emissions target is more robust to scientific uncertainty than a concentration target, it’s transparently dishonest. What is achieved by ignoring uncertainties? Cumulative emissions is an accounting notion that plays no physical role in the climate system. It legitimzes irresponsibility whereas feedbacks need to be taken into account in order to reach a concentration target. Concentrations have a real effect and we can therefore infer reasonable targets from paleo evidence (see Hansen et al.). We have no such basis for limiting cumulative emissions.
    Much of the litterature gives too much weight to abstract models and arbitrary statistics when it comes to formulating policy and ends up ignoring the biggest climate risks. Watch out for that! I don’t have a problem with purely scientific papers that use an unrealistic framework but when scientists advocate policies we need to call them on it whether they’re doing it in scientific journals or not. Slowing emissions in the short run and reaching lower atmospheric concentrations of GHGs in the long run is what mitigates these risks in the real world.

    Comment by Anonymous Coward — 19 Apr 2010 @ 11:12 AM

  189. CFU : ”
    Which you “forgot” when talking about the inconvenience of leaving fossil fuels.How inconvenient.”

    sorry to contradict you, I didn’t “forget” that. That’s exactly the question I’m asking: how inconvenient? meaning, at which level the use of fossil fuels will bring more inconvenience than advantages ? of course this can be answered only if you make a rather precise balance between them, which is obviously not the case if you simply state “FF are bad”.

    “The only inconvenience of renewables is that they can simply not support by themselves the industrial society.”
    You keep repeating this canard but it’s completely unsupported and false.”

    OK, let me know the objective facts that show that the development of industrial civilization is more correlated with the average temperature, or rather the temperature change , than with the use of fossil fuels ? “objective fact” means a quantitative method (correlation or whatever you want) which is blindly applied in the same way on these two parameters.

    Quoting AC : ” Technically and socially, nobody knows how to do reduce fossil fuel consumption to zero. Fossil fuel have no proven and scalabe substitutes for many valuable applications. ”

    (I would precise of course : nobody knows how to keep our way of life while reducing FF consumption to zero. There is absolutely no issue in reaching this target with a return to the ancient way of life. )

    C. Streif : “I have not seen a single study that says that wind and solar combined can’t run an industrialized economy according to “physics”.

    well, try to say that to chinese people ?


    On the contrary, the German physical society supports solar power generation in the sahara. The problem is that it’s expensive, and thatb redesigning the infrastructure for a complete switch is also very expensive (and it does use more land than nuclear or fossil).”

    It is not only the problem of price. The other problem is that electricity is far from solving all problems. Ask yourself why airlines company do not switch to electrical planes, that would be of course easily insensitive to volcanic ashes, to take a hot example. Every oil spike has resulted in an economic recession, although there was of course no shortage of electricity – explain me why the existence of expensive solar electricity could have change the littlest thing in that !! we simply do not lack electricity.

    Comment by Gilles — 19 Apr 2010 @ 11:44 AM

  190. “sorry to contradict you, I didn’t “forget” that.”

    Then why did you say that we couldn’t move from fossil fuels because it would be inconvenient?

    You “forgot” that every change is in some ways inconvenient. Because mentioning that in that post would be… inconvenient.

    Comment by Completely Fed Up — 19 Apr 2010 @ 12:32 PM

  191. Convenient SLR graphic:
    http://blogs.nature.com/climatefeedback/2010/04/sea_level_rise_defence_and_dev.html

    Comment by David B. Benson — 19 Apr 2010 @ 1:23 PM

  192. CFU : “Then why did you say that we couldn’t move from fossil fuels because it would be inconvenient?”

    I don’t see where I said that. We can (technically ) obviously move away from the fossil fuels-actually we will for sure. I said this will be impossible to keep our standard of living without them. The fact that many people – including you- are so reluctant to accept this idea is just the sign that it is very hard to accept that our civilization could recede durably. And this is the precise reason why I don’t think that people will do it willingly – before being forced by nature.

    Comment by Gilles — 19 Apr 2010 @ 2:55 PM

  193. “I don’t see where I said that. ”

    No, you never do admit to what you’ve said, do you.

    #170 “So if nobody advocates it, it means that stopping FF HAS some inconvenience”

    Comment by Comletely Fed Up — 20 Apr 2010 @ 3:05 AM

  194. Gilles (192): We can (technically ) obviously move away from the fossil fuels-actually we will for sure. I said this will be impossible to keep our standard of living without them.

    BPL: Yes, you say this over and over and over and over and over until our heads want to explode. But you’ve never given a convincing argument that it’s true. A high standard of living may well depend on using lots of energy. It does NOT depend on using lots of FOSSIL FUEL energy.

    Comment by Barton Paul Levenson — 20 Apr 2010 @ 4:26 AM

  195. “A high standard of living may well depend on using lots of energy.

    Comment by Barton Paul Levenson”

    In any case, such a dependency is only a loose coupling.

    With more problems in such a statement as, as another poster pointed out, the definition of “standard of living” has not yet been proposed.

    Comment by Completely Fed Up — 20 Apr 2010 @ 9:35 AM

  196. “BPL: Yes, you say this over and over and over and over and over until our heads want to explode. But you’ve never given a convincing argument that it’s true. A high standard of living may well depend on using lots of energy. It does NOT depend on using lots of FOSSIL FUEL energy.”

    Q : if there is no problem in producing lots of energy without lots of fossil energy, why should we produce ANY fossil fuel at all, and why don’t we forbid them simply just now?

    Other related question : can you explain why all other forms of energy are optional for industrial countries (meaning you can find industrial countries without nuclear, without hydro , without wind, without solar, ), but not a single one without fossil fuels ?

    rather unlikely that fossil fuels would just be cheaper than everything else everywhere (including in those countries totally deprived of them), but not much cheaper for crucial industrial uses, isn’t it?

    but I guess : known facts don’t prove anything for you – hypes on the consequences of average global temperature, whose global influence on industrial societies as a whole isn’t proved by ANY fact, is much more credible.

    Comment by Gilles — 21 Apr 2010 @ 11:39 AM

  197. May I please know where you got the data values to make that graph?

    Comment by Anonymous — 21 Apr 2010 @ 1:02 PM

  198. Gilles (196): Q : if there is no problem in producing lots of energy without lots of fossil energy, why should we produce ANY fossil fuel at all, and why don’t we forbid them simply just now?

    BPL: I didn’t say there was “no problem” to it. Obviously we need to spend the time, money and labor to switch over. We can’t just shut off fossil fuel use. We should, however, phase it out as fast as possible.

    Gilles: Other related question : can you explain why all other forms of energy are optional for industrial countries (meaning you can find industrial countries without nuclear, without hydro , without wind, without solar, ), but not a single one without fossil fuels ?

    BPL: For the same reason that you could find lots of countries in 1600 without firearms, but none without swords. That was the traditional weapon, used all over the world. It did not, however, mean that it was not advantageous to soldiers and nation-states to switch to firearms.

    Gilles: rather unlikely that fossil fuels would just be cheaper than everything else everywhere (including in those countries totally deprived of them), but not much cheaper for crucial industrial uses, isn’t it?

    BPL: I can’t quite parse that sentence, so I don’t know how to respond to it.

    Comment by Barton Paul Levenson — 21 Apr 2010 @ 2:47 PM

  199. “BPL: I didn’t say there was “no problem” to it. Obviously we need to spend the time, money and labor to switch over. We can’t just shut off fossil fuel use. We should, however, phase it out as fast as possible.”

    But do you agree we could rather easily shut off nuclear energy (even in France !) , wind energy, and solar panels without great difficulties, replacing them with fossil fuels, and that without more labor and money that what is needed to develop them ?

    so obviously something is different with fossil fuels. What is different is obvious : all other energies produce only electrical power (for which FF can also be used). But hydrocarbons have uses that cannot be entirely fulfilled by electricity. Full stop. You may desire that the reality should be different, but thinking that it will obey your desires is just childish. Again, there is no modern society without FF,there has been nowhere and never, and believing this has no particular meaning is just ignoring reality.

    BPL: I can’t quite parse that sentence, so I don’t know how to respond to it

    I elaborate (again) : the fact that NO industrial country has developed without FF means that, at least for some applications, FF aren’t easily replaceable.

    This is NOT true for all applications, since for electricity generation, some of industrial countries have almost completely used other forms of energy (hydropower or geothermal power namely).

    So the fact that BOTH
    a) when it was possible, fossil fuels have indeed been replaced by other means for some specific needs
    AND
    b) they have never been replaced for other specific needs

    proves that they are indeed very difficult to replace for needs b),(because if not there is no reason why they wouldn’t have been already replaced like a) ).

    Hence I don’t see how you justify your confidence that it must be possible. You haven’t any known facts that support it.

    Comment by Gilles — 22 Apr 2010 @ 8:27 AM

  200. AFP reports that the Director of Dhaka’s CEGIS considers that the rise of sediments from the Himalayas would enable most of the Bangladeshi coastline to rise on par with the sea level.
    Any clue about the actual level of sedimentation vs delta sinking?

    Comment by François — 22 Apr 2010 @ 8:55 AM

  201. “I elaborate (again) : the fact that NO industrial country has developed without FF means that, at least for some applications, FF aren’t easily replaceable.”

    Well NO industrial country has had the level of technology.

    Therefore the past is no indication of future performance.

    Comment by Completely Fed Up — 22 Apr 2010 @ 10:26 AM

  202. “I elaborate (again) : the fact that NO industrial country has developed without FF means that, at least for some applications, FF aren’t easily replaceable.”

    What applications?

    “b) they have never been replaced for other specific needs ”

    What needs?

    Magnus Pike never waved his hands in an argument half as much as you do.

    Comment by Completely Fed Up — 22 Apr 2010 @ 10:34 AM

  203. “I elaborate (again) : the fact that NO industrial country has developed without FF means that, at least for some applications, FF aren’t easily replaceable.

    b) they have never been replaced for other specific needs ”

    What other specific needs? You specifically mention nothing, so therefore there are no such needs.

    Comment by Completely Fed Up — 22 Apr 2010 @ 1:05 PM

  204. Frank Giger:

    It might help if you actually followed a thread and understood what people are talking about before you start threatening to call politicians and ask them to vote based entirely on your own ignorance. Your complaint at 745 about people discussing “[m]ass extinctions” and possibly “95% of the human population [being] destroyed” is entirely predicated on your own failure to find out why that conversation had begun in the first place.

    Whatever your reason for not doing so, I do hope that you will perhaps take away from this that your own bias can cause you to react hastily and to therefore reach incorrect conclusions — not to mention that it makes you look intellectually lazy.

    So, here is where I believe the discussion started:

    473 Barton Paul Levenson says:

    PKthinks (461): the mainstream media and policy makers have exaggerated the threat to such a degree that people then lose faith in the science itself.

    BPL: What part of “human civilization could be completely destroyed if business as usual continues” do you not understand?

    I could be wrong, but I would have thought it fairly obvious that if we do absolutely nothing and continue to burn fossil fuels at the current rate, a point will likely come in the future where the earth is too warm for humans to inhabit in large numbers?

    You may have had a point if your complaint had been about the fact that other people reading this thread might not have known why the conversation had originally started, and so, probably would have gone away the wrong impression. Sadly, that wasn’t your point.

    Do remember to get in touch with your “Congressman and Senator” again and tell them that you were a little hasty in your original reaction, and that they should now “vote [for] AGW legislation”, won’t you? It’s a little sad that it only took a few people saying something that you didn’t like for you to react in that way, given that you have previously said that the science is sound.

    Comment by Amy — 23 Apr 2010 @ 1:13 AM

  205. “What other specific needs? You specifically mention nothing, so therefore there are no such needs.”

    Oh, sorry, CFU, I thought you knew them : transportation, heating, metallurgy, cement, glass, paper,plastics, glues, paintings, medicines, detergents, fertilizers, and many more…

    Of course there are substitutes for everything – but as a general rule, more expensive , since otherwise they would already have been use instead. Now if you’re claiming that you don’t see why replacing everything with more expensive techniques would impact in any way the global economy, I wonder what “expensive” really means for you. Note that all alternatives use a lot of the above mentioned commodities, and that their current price is calculated with everything produced by cheap fossil fuels

    Comment by Gilles — 23 Apr 2010 @ 5:25 AM

  206. #189, @ AC
    Well, AC, if you say now that the aim should be an emissions reduction to 5% or less of current emissions for something approaching climate stabilization , then we have no quarrel except over words on this particular issue. I also agree that coal is the most important factor .
    But I must admit I am a bit bemused by your attitude. You tell me I’m harbouring fantasies because I said to stabilize climate it would be necessary to switch to 100 % non-fossil energy in the end – not that outlandish a claim surely in climate change circles–, yet for your own presumably more realistic mitigation scenario you assume that cutting global emissions by two thirds and finally to 5% is no big deal, as we won’t have rising living standard, so India and China, according to your assumption, will not develop significantly, but mysteriously the Chinese and the Indians nevertheless will agree to “phase out coal” as Hanses so coyly phrases it (“by 2030″, he adds), meaning in your scenario that they will get their plants converted to CCS, thereby doubling their energy costs despite the fact that the majority of the population is still poor (while the Americans still drive around in big cars because all of the oil can be used up anyway). Uhm, is this any less fantastic than what I said?
    You also told me I was careless in the way I cited literature (“citing abstracts out of context” or “not having understood the argument”), which I find a bit puzzling when all the articles I cited and even the one you cited did in fact support my assertion (and the main point of our whole discussion) that within the time scales we’re talking about total emissions are what counts for climate outcome because of the longevity of CO2, among other things, so that to stabilize emissions have to go down to essentially zero, while you didn’t cite a single source that supported your original assertion that we will never have to cut radically because we will be able to emit more cumulatively if we cut some now. (The one you cited, Hansen, flatly contradited you according to my standards. Yes, I know, in your last comment it becomes clear that your interpretation of what does and doesn’t constitute a radical cut is somewhat idiosyncratic, but even then… )
    Thanks for telling me that your judge the merit of a scientific paper by author’s politics ;). I do hope you weren’t serious about that one. I still think calling Matthews a “contrarian” because you didn’t like his conclusions (he doesn’t look like one, by the way, I googled his picture) wasn’t a good idea.
    Also by the way, like you, I used to think that Germany had met its Kyoto target through the crumbling GDR economy. However, I researched this last year and it’s not true. (You’ll find a lot of the data on this page:http://www.umweltbundesamt.de/energie/index.htm) Primary energy use has shrunk very little, emissions went down a lot. Most poignantly, electricity use has gone up, yet emissions from electricity have fallen steeply. Most of what would have been needed to reach Kyoto is from clean energy, some reduction in growth is from energy efficiency and if you ask me the switch from oil to gas as the main heating fuel also helped. Yes, I know the French emit less thanks to nuclear power (so are you a supporter of nuclear energy?). They also have warmer winters (less heating) and travel less than the Germans do. Fact is Germany had more ambitious Kyoto targtets than other countries and met them.

    Comment by C. Streif — 23 Apr 2010 @ 8:19 AM

  207. “and finally to 5% is no big deal, as we won’t have rising living standard, ”

    And what about your living requires the burning of fossil fuels?

    Why not define living standard as the Swedes do: how well you live your life, and NOT how the US does: how much more money do you have than someone else.

    Comment by Completely Fed Up — 23 Apr 2010 @ 10:23 AM

  208. “What other specific needs? You specifically mention nothing, so therefore there are no such needs.”

    Oh, sorry, CFU, I thought you knew them : transportation,

    Electric cars.

    heating,

    Passive heating solar.

    metallurgy,

    Are not made from fossil fuels.

    cement,

    Curing causes emission of previously held Carbon.

    glass,

    Isn’t made from fossil fuels

    paper

    aren’t made from fossil fuels

    ,plastics,

    are made instead of burning fossil fuels, retain the carbon

    glues,

    Horses hooves

    paintings,

    Yeah, big industrial. you know I think you mistake “oil painting”

    medicines,

    aren’t made from fossil fuels

    detergents,

    aren’t made from fossil fuels

    fertilizers,

    Shit from horses. Not made from fossil fuels

    and many more…

    given you’ve managed to miss 90% with the ones you stated, many LESS would be closer to the truth.

    Comment by Completely Fed Up — 23 Apr 2010 @ 10:26 AM

  209. “with everything produced by cheap fossil fuels”

    Only if you don’t pay the externalised costs.

    How much will it cost in energy and money to pull back all the carbon emitted? then store them.

    Fossil fuels are EXPENSIVE.

    Wind is cheapest.

    Comment by Completely Fed Up — 23 Apr 2010 @ 10:28 AM

  210. “Oh, sorry, CFU, I thought you knew them : transportation,”

    Electric cars.

    “heating,”
    Electric fires. Insulation. Solar passive heating.

    ” metallurgy”

    These use metals not hydrocarbons.

    “, cement”

    Still doesn’t use fossil fuels.

    “, glass”

    Uh, made of silicon not carbon.

    “, paper”

    Wood, not petrol.

    “,plastics”

    If you burn the fossil FUEL you can’t make plastic out of it.

    “, glues”

    Horse hooves

    “, paintings”

    Yeah, big industry.

    Still doesn’t use fossil fuels.

    “, medicines”

    Hmmm. So instead of my cancer cure, all I need is a gallon of five-star…?

    “, detergents”

    Fat, caustic soda and lye.

    “, fertilizers,”

    Cowshit.

    ” and many more…”

    ..that have nothing to do with fossil fuels…

    Comment by Completely Fed Up — 23 Apr 2010 @ 11:44 AM

  211. Gilles (199): so obviously something is different with fossil fuels. What is different is obvious : all other energies produce only electrical power (for which FF can also be used). But hydrocarbons have uses that cannot be entirely fulfilled by electricity

    BPL: Ever heard of “biodiesel?” How about “ethanol?” “Methanol?”

    Comment by Barton Paul Levenson — 23 Apr 2010 @ 1:38 PM

  212. C. Streif,

    You have a fertile imagination. You made up most of the statements and positions you attribute to me. Have fun arguing with strawmen.

    As to the part of your post that’s not laden with strawmen…
    Germany burns more than France but also more than Swizterland and Sweden which are hardly warmer coutries.
    Yes, Germany is making progress but the fundamental problem is that electricity usage is out of control for a country which is phasing out nuclear and I have not seen any indication that people have come to terms with that. Travel may be excessive as well as you say. Frivolous air travel certainly needs to be curbed and rail fees are too expensive compared to the price of gas.
    You say that “emissions from electricity have fallen steeply” but once again your claim supported by spin rather than figures. Your link has emissions for elecricity generation roughly stable after the first years of reunification. 2000-4 emissions are higher than 1995-9 and the only reason 2005-2009 are lower is that the preliminary figures for 2009 are very low, due to the economic crisis I presume. For all the “clean” and “green” stuff, 2005-2009 emissions are still going to be higher than 1995-9 in spite of the crisis. The amount of electricity produced has no effect on the climate. Only emissions matter, and they stopped falling in 1993.

    Comment by Anonymous Coward — 23 Apr 2010 @ 5:25 PM

  213. > there are substitutes for everything – but
    > as a general rule, more expensive

    You ignore the externalized costs, which for CO2 include climate change.
    These get handled eventually by governments — lead in pipes and gasoline; sulfur in fuel oil; asbestos in everything; PCBs in everything, and so on.
    http://www.ginandtacos.com/2008/08/31/atheistsfoxholes-libertariansairplanes/

    Comment by Hank Roberts — 23 Apr 2010 @ 9:40 PM

  214. “Oh, sorry, CFU, I thought you knew them : transportation,”

    ….
    ..that have nothing to do with fossil fuels…

    CFU, you really don’t understand the point. Of course there are substitutes for all that. The only thing is that they are generally much more expensive, less convenient and/or can be produced at a smaller scale. The point is NOT whether we can live without FF or not. We obviously can, for the very simple reason that we already did in the past and that many people still do currently. The point is if that we cannot produce as much as we do without FF, because everything would be much more expensive (including substitutes energy) and we wouldn’t have enough money to buy so much. If everything is more expensive, you’re simply poorer, and the inflation-corrected GDP is lower.

    The only question is : how much lower? well look at the correlation between and GDP and FF and you will have a gross answer.
    BTW, you don’t seem to know that metals needs reduction of their oxides by carbon – I know, we could use charcoal or hydrogen, but read again above.

    Comment by Gilles — 24 Apr 2010 @ 12:56 AM

  215. RE- The many comments by Gilles.

    Please explain why you think that working toward long term climate and economic stability by a near term transfer to renewable energies, even at the expense of a short term reduction in standard of living and GDP, is preferable to a complete crash of civilization from environmental problems and increasing scarcity of fossil fuels (your admitted prophesy). Don’t tell me that this is impossible because it hasn’t already been done. A crash is a crash. Don’t tell me that developing nations will be hurt because, ultimately, a crash is a crash.

    If we can’t make it on renewable energy resources, we crash. If we don’t try, we crash. Can you not think of any way out of this mess? If you don’t think it is even worth trying to solve this problem, then why are you posting at all? Do you just enjoy telling others that the future of their progeny is worthless?

    Steve

    Comment by Steve Fish — 24 Apr 2010 @ 10:44 PM

  216. Gilles (214): The point is if that we cannot produce as much as we do without FF, because everything would be much more expensive (including substitutes energy) and we wouldn’t have enough money to buy so much.

    BPL: Yeah, but “the point” you list happens to be egregiously wrong.

    Comment by Barton Paul Levenson — 25 Apr 2010 @ 7:53 AM

  217. > we wouldn’t have enough money

    Nonsense. It’s almost a trivial amount of money compared to the natural variation in the amount of money in the financial system.

    Look at just the last five years. The amount of money in existence varied enormously.

    How can this happen? Because it’s a bookkeeping term.

    The real wealth isn’t money. There’s your problem right there.

    This is a bookkeeping problem.

    Comment by Hank Roberts — 25 Apr 2010 @ 10:55 AM

  218. Steve :” If you don’t think it is even worth trying to solve this problem, then why are you posting at all?”

    But I didn’t say it wasn’t worth trying ! I said that it was very unlikely that we’ll succeed in mitigating the effects of fossil depletion enough to keep our standard of living, and that I wasn’t sure at all that there are enough fossil fuels to make climate change that dangerous. If you have bad harvest and you fear starving for death, you’re not much interested in doing a diet , are you ?

    Of course it would be fine to be able to power a society like ours only with renewables ! again, why should I be against that ? this wouldn’t make any sense. My position is
    1) that I doubt very much that renewables will be enough to avoid problems linked with fossil depletion (the most probable being economic and financial crashes)
    2) that the close coming of fossil peak and the associated economic problems will make climate change rather immaterial for most people – compared with these issues. SRES scenarios simply ignore totally the problems arising from depletion of natural resources.
    3) much likely, if renewables were enough to continue the growth, for instance, they wouldn’t change at all the total amount of burnt fossil fuels – mankind greed , or more simply basic needs for the poorest people , would simply make it use fossil fuels PLUS renewables to produce the maximum amount of wealth it can.

    so I’m posting for the very same reason as anybody posting here : to alert on what I think is the most critical issue for the next future. We just differ on its nature.

    BPL: Yeah, but “the point” you list happens to be egregiously wrong

    BPL, I’ll wait to see a society without fossil fuels, and having a standard of living comparable to ours, before believing you. But I don’t think we’ll have to wait much before seeing the effects of oil depletion – actually I think we are just seeing the beginning.

    Comment by Gilles — 25 Apr 2010 @ 11:14 AM

  219. HR :”Look at just the last five years. The amount of money in existence varied enormously.
    How can this happen? Because it’s a bookkeeping term.
    The real wealth isn’t money. There’s your problem right there.”

    I couldn’t agree more to that. The real wealth is NOT money. It’s the amount of goods you can produce per work hour. Money is just a symbolic transcription of that (actually money is just a RELATIVE allocation of the fraction of goods you are allowed to consume. Increasing or decreasing the global amount of money produces only inflation/deflation. But actually the amount of money didn’t vary that much these last years in regard to the recession).
    When I said “we won’t have enough money”, i just mean that with the diminishing energy input, we’ll be simply poorer – because everything will get more expensive compared to our income.

    Aren’t we slightly OT with respect to the original title of the thread ? ;)

    Comment by Gilles — 25 Apr 2010 @ 1:22 PM

  220. “BPL, I’ll wait to see a society without fossil fuels, and having a standard of living comparable to ours, before believing you”

    If you’re going to wait, then do so.

    Stop posting twaddle about things you don’t know and STFU.

    WAIT for a fossil fuel free future, stop complaining that it’s impossible.

    Comment by Completely Fed Up — 25 Apr 2010 @ 2:25 PM

  221. Gilles III 218: I’ll wait to see a society without fossil fuels, and having a standard of living comparable to ours, before believing you.

    Gilles, Jr., 1910: I’ll wait to see a society without horse-drawn transportation, and having a standard of living comparable to ours, before believing you.

    Gilles Sr., 1860: I’ll wait to see a society without slavery, and having a standard of living comparable to ours, before believing you.

    Comment by Barton Paul Levenson — 25 Apr 2010 @ 5:04 PM

  222. 221 : BPL : so you seem to belong to the cornucopian church believers, who think that “if everything has grown in the past, then it cannot do anything else than grow in the future ?” interesting ..

    interesting also to remark that your period of comparison is strictly coincident with the development of fossil fuels in general, and oil in particular. Do you have another historical example ?

    Comment by Gilles — 26 Apr 2010 @ 1:02 AM

  223. “[Wealth is] the amount of goods you can produce per work hour.”

    What about services?

    And ignoring that issue for the moment, surely “value of goods” would be more apposite than “amount of goods?” One Stradivarius is worth any number of factory-made Skylark violins. (Actually, it’s worth far more than all the Skylarks ever made.)

    It may seem nit-picky, but a degraded environment is a negative “good,” and the economic system needs to account for that. Doing so means going beyond simplistic “amounts”–as discussions of the definition of wealth say, the question ends up invoking “values” of all sorts.

    Comment by Kevin McKinney — 26 Apr 2010 @ 7:17 AM

  224. Gilles (222): 21 : BPL : so you seem to belong to the cornucopian church believers, who think that “if everything has grown in the past, then it cannot do anything else than grow in the future ?” interesting ..

    BPL: Not even remotely. That’s why I care about stopping global warming.

    Gilles: interesting also to remark that your period of comparison is strictly coincident with the development of fossil fuels in general, and oil in particular. Do you have another historical example ?

    Seigneur Gilles de Point du Lac (1789): I’ll wait to see a society without serfs, and having a standard of living comparable to ours, before believing you.

    Gilles le Seigneur (1183): I’ll wait to see a society without two-field rotation, and having a standard of living comparable to ours, before believing you.

    Guillius Gallensis (353): I’ll wait to see a society that doesn’t sacrifice goats to Ceres, and having a standard of living comparable to ours, before believing you.

    Gil (512 BC): I’ll wait to see a society that doesn’t sacrifice at least one child to the harvest gods every spring, and having a standard of living comparable to ours, before believing you.

    Gl (11,000 BC): I’ll wait to see a society without mammoth hunts, and having a standard of living comparable to ours, before believing you.

    Comment by Barton Paul Levenson — 26 Apr 2010 @ 7:43 AM

  225. RE- Comment by Gilles — 25 April 2010 @ 11:14 AM:

    You have missed my point. Degradation of the biosphere and depletion of fossil fuels will both by themselves, or in any probable combination, ultimately result in conflict, starvation, a very large die off, and a major crash of civilized society.

    You say- “so I’m posting for the very same reason as anybody posting here : to alert on what I think is the most critical issue for the next future. We just differ on its nature.” This is not quite correct. Most people posting here about critical issues are also offering potential solutions, while you are not. Just saying that won’t work, and that won’t work, and that won’t work is just argumentative and pointless. There is no one “critical issue” if the outcomes of all of them are the same without some intelligent action.

    Steve

    Comment by Steve Fish — 26 Apr 2010 @ 10:50 AM

  226. BPL : actually all examples between the apparition of agriculture and the industrial civilization didn’t have very different standard of living – and they all disappeared sooner or later. Not particularly a good example to argue we are immune against a decline.

    ““[Wealth is] the amount of goods you can produce per work hour.”

    What about services?

    To develop services, you have to increase the part of population that is not busy with the production of food or commodities – that’s exactly increasing productivity.

    “It may seem nit-picky, but a degraded environment is a negative “good,” and the economic system needs to account for that.”

    Well, maybe, but it’s always the same question : at which point do you estimate that it becomes more costly that the benefit you draw from the civilization ? that’s far from being obvious …

    Steve : ” Most people posting here about critical issues are also offering potential solutions, while you are not. Just saying that won’t work,”

    more exactly , they claim that they believe there is a solution. That is not exactly “offering a solution”. I could also claim that I believe that we’ll find a solution to climate change and that we don’t need to reduce FF consumption : why is it more unreasonable than claiming that we could replace fossil fuels without any problem?

    if you bet on unknown solutions, you can bet on anything you want, after all.

    Comment by Gilles — 26 Apr 2010 @ 6:02 PM

  227. “if you bet on unknown solutions, you can bet on anything you want, after all.”

    They aren’t unknown solutions.

    Solar passive heating. Known.
    Solar PV. Known.
    Wind power. Known.
    Tidal power. Known.
    Hydroelectric. Known.

    The solutions are only unknown to gullible here who sticks his fingers in his ears and goes “lalalalala! You’re not looking!”.

    Comment by Completely Fed Up — 27 Apr 2010 @ 2:53 AM

  228. ““if you bet on unknown solutions, you can bet on anything you want, after all.”

    They aren’t unknown solutions.”

    please show me evidence that it is enough to avoid the use of fossil fuels, and apart from hydropower (which is of limited application), that it is even enough to avoid the use of thermal plants at all. Look at the figures, and stop denying the mere reality (and worse accusing the others of doing it).

    Comment by Gilles — 27 Apr 2010 @ 7:01 AM

  229. “please show me evidence that it is enough to avoid the use of fossil fuels”

    Yet again Mr Amnesia strikes again:

    http://www.realclimate.org/index.php/archives/2009/10/an-open-letter-to-steve-levitt/

    Comment by Completely Fed Up — 27 Apr 2010 @ 9:35 AM

  230. RE- Comment by Gilles — 26 April 2010 @ 6:02 PM:

    Because you say- “more exactly , they claim that they believe there is a solution” – you apparently don’t believe that there is a solution. So, why bother to post? What is gained by telling others that all is lost and there is nothing to do about it? Please explain your motivation.

    Steve

    Comment by Steve Fish — 27 Apr 2010 @ 11:38 AM

  231. 230 Steve : i thought this was a scientific site, and I don’t think that the first goal of science is “proposing a solution”, but rather telling the truth.

    Proposing a solution requires first a clear identification of the “problem”. Well thinking more about it, I’m not sure to be quite certain about what is the problem. It seems that the problem is to keep as much as possible our standard of living without any of its inconvenience – no pollution, no CO2, no finite reserves. Actually very close to the dream of immortality. Well I shall admit that it is a very ancient dream of mankind – kind of Faust archetype. But it is also basically a very childish idea. Things never last eternally. yes , climate may change, sea level can change, energy resources can be exhausted. And even our civilization can die (actually EVERY civilization has died isnt’it?) I don’t think mankind as a whole is threatened. We are a very robust species. The only one that can survive from the torrid desert to the icy poles (even without fossil fuels ! ). More, we seem to like living in difficult and hostile environments – we even climb very high mountains and dive under deep water for leisure, although it is very far from our biotope. So I don’t worry very much about mankind. The only real problem is that we don’t want to give up our comfortable houses, cars, travel for holydays. Sorry again, “ours” means only “the 10 % richest people in the world during the richest period of its whole history”. Maybe two billion lives on a total of 80 billions – the other 78 billions and probably a big number of coming dozens of billions have or will never know that kind of life , anyway. But I don’t think either that these things will disappear very rapidly. Even fossil fuel exhaustion will be very gradual , may be – 2 or 3 % a year, even less. That’s enough for them to disappear totally after some centuries, but individually, things will just become more difficult or expensive during our lifetime, but not vanish totally. Only our grand children or grand-grand children may not know things like airplanes or cars – but if they never met them, they won’t suffer much from their non-existence.

    So again, which “solution” to which problem ?

    Comment by Gilles — 27 Apr 2010 @ 4:41 PM

  232. > I’m not sure to be quite certain about what is the problem.
    http://www.nature.com/nature/journal/v425/n6956/full/425365a.html

    Everything else will happen, but that’s the fastest and most immediately disastrous.

    Comment by Hank Roberts — 27 Apr 2010 @ 11:13 PM

  233. “So again, which “solution” to which problem ?”

    The problem of your inability to listen to an argument and make intelligble points.

    Oh, and the problem of CO2 production causing climate change that will at best destabilise and at worst (and likely under BAU) the collapse of our civilisation and our reversion to a rude existence living from hand to mouth.

    The solution is simple to everyone else on the planet: stop producing CO2 from fossil fuels by burning them.

    Comment by Completely Fed Up — 28 Apr 2010 @ 2:51 AM

  234. CFU :” the collapse of our civilisation and our reversion to a rude existence living from hand to mouth.

    The solution is simple to everyone else on the planet: stop producing CO2 from fossil fuels by burning them.”

    I don’t think you really listen to what I’m saying. If stopping producing CO2 causes ALSO a collapse of the civilization, how can it be considered as a “solution” to avoid the collapse of civilisation ?
    and where is the scientific assessment that the risk of collapsing through stopping FF is much much lower than the risk of climate change ? where do they have been compared in an objective way, with the same , objective, unbiased tools ? I saw here only wishful thinkings !

    Comment by Gilles — 29 Apr 2010 @ 12:51 AM

  235. “Everything else will happen, but that’s the fastest and most immediately disastrous.”
    The effects of fossil (first oil) depletion are just starting now, and I really think that most people in the world consider them as fastest and most disastrous that the change of the pH of oceans. But I can be wrong, try to check around you ?

    Comment by Gilles — 29 Apr 2010 @ 12:55 AM

  236. Coastal fishermen in the third world would disagree.

    They don’t use much oil anyway. But they DO fish.

    Comment by Completely Fed Up — 29 Apr 2010 @ 8:14 AM

  237. I was wondering, when you used the reservoir correction, did you take into account the man made lost lakes?

    Lake aral for example will dwarf the biggest man made lakes.

    And when counting the volume of manmade lakes did you use max volume? Or the mean volume in lake?

    Comment by Hmmm — 5 May 2010 @ 7:21 AM

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