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Comments 63951 to 64000:

  1. Denialgate - Internal Heartland Documents Expose Climate Denial Funding Network
    I hate to be the fly in the ointment here, but I wonder if this revalation is already too late. Looking at reader comments on news sites and blogs over the last couple of years leads me to feel that the job of sowing doubt has already succeeded. Have people had long enough to make up their minds, set their opinions and move on to other, more recently newsworthy topics? I hope not. I cannot back up my conclusions with data but feel that the denialists have given themselves a very strong lead and that few in the media will be bothered to return to climate science as a newsworthy topic. Sorry to be so uncharacteristicaly pessimistic.
  2. NASA Mission Takes Stock of Earth's Melting Land Ice
    KR @58, for the first time I am going to disagree with you (but not by much). Specifically, I am suggesting that Church et al, 2011 probably gives more accurate figures than Milly et al 2010. There results are as follows: The figures are not strictly comparable due to differing time periods, so convenience I have calculated Milly's figures for the 1993-2007 interval as a weighted average ((2*1993-2003 +2003-2007)/3). I have also combined contributions from all forms of ice melt, again for convenience of comparison. Finally, I have placed the difference between the equivalent Milly and Church figures (Milly - Church) in brackets after each figure: Observed: 2.9 mm/year (-0.32 mm/year) Thermal Expansion: 1.18 mm/year (+0.3 mm/year) Glaciers & Icesheets: 1.5 mm/year (-0.23 mm/year) In each case Milly's results are within the error bounds of Church et al's analysis, hence the small disagreement. In both cases, the GRACE analysis discussed in the OP strongly suggests that they have overestimated the contribution of ice melt. Specifically, over the period of the GRACE analysis, total ice melt contribution to sea level was 1.5 mm per year. Over the most comparable period from Milly et al (2003-2007) the combined ice contribution was 2.1 mm per year, suggesting Milly has over estimated the ice contribution by 40%, while Church has overestimated it by 61%. That would suggest that Church et al's residual for tidal gauges and satellite measurements should be around 1.35 mm per year, which is a large hole in their budget. It should be emphasized that these figures are approximate only because, firstly the periods of analysis do not strictly correspond, and secondly because of the short duration of the GRACE study which means it is significantly influence by short term effects. In particular, the GRACE analysis includes the very wet Asian Monsoon of 2010 which is likely to have contributed substantially to snow fall in the Himalayas, significantly altering the glacial mass balance compared to the preceding decade. Never-the-less there is clearly still some way to go before we can be entirely confident in Sea Level budgets. Finally, you will have noticed that Church et al show a greater contribution to sea level rise from ground water depletion than to Milly et al, but that net contribution from terrestial storage is negative. Church's estimate is based on that in Konikow 2011, with Konikow being a co-author of Church et al. (More on Konikow 2011 later.) I notice that Norman now pins his confidence in Wada et al, 2010. In doing so, he ignores the careful analysis by Wada comparing (surprise, surprise)recharge to abstraction (withdrawals). Further, he quotes a document that concludes global groundwater depletion was 243-323 km^2/year with an annual contribution to sea level rise of 0.8 mm/year as supporting his claims that groundwater depletion was about 545 km^3/year, and the sea level contribution was 1.52 mm/year. He is also citing a paper that claims that groundwater depletion averages at 40% of total withdrawals in support of his methodology of ignoring recharge. Apparently he has no sense of irony. Given Norman's reliance on Wada (a distinct improvement from his previous position if he actually accepts their results), it is worthwhile quoting Konikow's critique of Wada et al:
    "The first two estimates are based on a limited number of direct aquifer evaluations. The estimate of Wada et al.[2010] is derived using an indirect, flux‐based water budget approach that assumes that groundwater depletion is equal to the difference between natural recharge and withdrawals—an approach that is not based on observations of groundwater conditions. Recharge values are derived from global‐scale modeling designed to estimate “diffuse” recharge from climatic data and soil properties [Döll and Fiedler,2008]. This methodology does not calculate recharge from surface‐water bodies, nor adjust depletion estimates in accordance with Theis’ [1940] principles, which are applicable regardless of climate (Wada et al. [2010] only allow this for humid climates). Even in the Nubian Aquifer system—the classical example of a fossil groundwater aquifer having no modern recharge—about 25% of the total withdrawals in 1998 were offset by (and derived from) reductions in natural discharge from the system (such as to springs and oases) [CEDARE, 2001]. The global modeling approach to estimating natural recharge also does not account for “non‐natural” non‐diffuse recharge, such as leakage from canals, sewers, or pipelines, or from artificial recharge—none of which depend on climate and soil characteristics inherent in their recharge estimation model. Hence, the flux‐based water budget approach of Wada et al. [2010] can substantially overestimate groundwater depletion. Problems with the approach of Wada et al. [2010] are illustrated by examining their results for areas in the US where depletion data exist. Figure 2 of Wada et al. [2010] shows highest rates of depletion in four areas in the US (red zones, rated at 300–1000 mm/yr of depletion), which appear to include the Los Angeles and San Diego areas of southern California. In the Los Angeles area, depletion is closely tracked by local agencies. These data and analyses (see auxiliary material) indicate that from 1961 to 2008 the cumulative change in storage was an increase of ∼0.20 km3, and in 2000 was a decrease of ∼0.04 km3/yr. This corresponds to a rate of depletion of less than 20 mm over the area of resolution of the map of Wada et al. [2010]. In the San Diego area, there is no large‐scale development of groundwater, and no reported depletion problems of significance."
    Konikow uses empirical measurements of groundwater depletion in the US to calibrate his estimates. While superior to Wada et al, this approach of assuming the USA is typical of global ratios between depletion and withdrawals is dubious. Consequently we should also expect further improvements on Konikow's, and hence Church et al, 2011's, estimates of groundwater depletion.
  3. Denialgate - Internal Heartland Documents Expose Climate Denial Funding Network
    Not to mention the admission of the existence of a denialist army, as they say they are working in
    coordination with external networks (such as WUWT and other groups capable of rapidly mobilizing responses to new scientific findings, news stories, or unfavorable blog posts)
    (my emphasis added). Do they fund the inciters of hatred, who post email addresses such as Katharine Hayhoe's? Where's my share of the billions supporting AGW 'alarmists' we are always hearing of? I could do with $80K to build a new web site ... tax free, of course.
  4. Climate mythbusting at Lane Cove, Sydney on Feb 28
    Shame I can't get to Sydney on that date (was there last week). I'd take you up on the challenge. Come to Melbourne, John.
  5. NASA Mission Takes Stock of Earth's Melting Land Ice
    KR @60 Since you are done posting on this topic. I still feel the need to defend myself from your claim that I am not taking in groundwater replenishment. Also on the impoundment equation, unless they use groundwater specifically for filling of a reservoir, the -0.25 given for impoundment would include all sources of water not just ground water. Reservoirs are generally filled by river flow and the source of this preciptiation is not singular to groundwater, melting ice will also contribute via evaporation of ocean water. Anyway here is the link that shows water abstraction and recharge rates on a global scale. This piece does address clearly Tom Curtis's objection. Nonrenewable water abstraction. Another article from the American Geophysical Union that is supporting the point I had made. American Geophysical Union paper. Considering there are experts in the field that are indicating that a quarter of current SLR may be caused by groundwater mining, maybe you should not be so convinced my position is wrong. It could be wrong but you should be open to that as a real possibility and in the future with more study I believe it will be demonstrated that the position I have taken is the correct and scientifically supported one. Wait and see but keep an open mind to this possibility before you slam the messenger. Thanks.
  6. Denialgate - Internal Heartland Documents Expose Climate Denial Funding Network
    Deniergate. Heartlandgate. These are incredibly devastating revelations-- next a list of all those fake skeptic scientists who have ties with Heartland please. "This influential audience has usually been reliably anti-climate and it is important to keep opposing voices out." This shows the fake skeptics to be total hypocrites when they falsely claim climate scientists play gatekeepers-- they are accusing others of doing exactly what they are doing (also in terms of Heartland et al. falsely claiming that climate scientists are "in it for the money"). It also calls into question the relationship between Forbes and groups like Heartland and WCR. Who else has fallen under Heartland's spell? Why was this information hidden from people? So many questions just waiting for some good investigative reporters to sink their teeth into.
  7. Bert from Eltham at 12:25 PM on 15 February 2012
    Denialgate - Internal Heartland Documents Expose Climate Denial Funding Network
    This just goes to show if there is a real conspiracy it will eventually leak. Bert
  8. New research from last week 6/2012
    No Lou, I remarked on much the same thing when Ari was writing the post. A cooling effect of -1.6 W/m2 is exactly the number that Hansen & colleagues have come up with too. It would also explain why ocean thermal expansion appears to have tapered off a bit in the last decade, whilst the contribution to sea level rise from ice melt has accelerated. Meanwhile, of course, the incremental greenhouse gas forcing is growing a tiny wee bit every week. (cue ominous orchestral music..........) We will get around to covering this. Like you say, it seems to have slipped under the radar.
  9. Denialgate - Internal Heartland Documents Expose Climate Denial Funding Network
    Deep Climate has a good summary of some of the main documents as well.
  10. Denialgate - Internal Heartland Documents Expose Climate Denial Funding Network
    And don't miss this nugget from their Strategy Memo, which John Cook Tweeted earlier: "We are pursuing a proposal from Dr. David Wojick to produce a global warming curriculum for K-12 schools. Dr. Wojick is a consultant with the Office of Scientific and Technical Information at the U.S. Department of Energy in the area of information and communication science." "His effort will focus on providing curriculum that shows that the topic of climate change is controversial and uncertain - two key points that are effective at dissuading teachers from teaching science." Maybe a journalist should give a call over to OSTI at DOE, to get their reaction.
  11. Denialgate - Internal Heartland Documents Expose Climate Denial Funding Network
    Oh look, another 'gate'.
  12. Denialgate - Internal Heartland Documents Expose Climate Denial Funding Network
    Please notice a couple of things. Most obviously, they believe their own bullshit, or at least most of it. And note what is not there, There is no mention of any attempt to understand and explain climate, only of attempts tho attack the current understanding of the climate. This is, as expected, evidence of wanting science to come up with politically palatable conclusions. No consideration of the possibility that they might be up against inexorable laws of nature and might have to modify their politics accordingly. Magical thinking, if they can argue well enough against something then it must be false.
  13. New research from last week 6/2012
    Am I the only one here who thinks the Makkonen, et al.paper on the climate implications of reducing aerosol pollution is terrifying? I'm in no way questioning their conclusions, nor do I mean to suggest this is a very recent discovery. But I find it mind blowing how serious the potential impacts of this factor could be, and how far beneath the radar it manages to fly. The evidence of our "Faustian bargain", as Hansen calls it, has been right in front of us for some time. All one has to do it look at the infamous bar graph from the latest IPCC report that shows the forcing from various factors, and then realize that those shielding aerosols are a very nasty and visible form of air pollution (ask China) that various countries either have been limiting for years or are now starting to get serious about controlling.
  14. Denialgate - Internal Heartland Documents Expose Climate Denial Funding Network
    Dana, I'd be surprised if Idso didn't act as a conduit, funneling a chunk of that money on to others. What I wouldn't give to see all of their past budgets as well. I'm sure Anthony will claim that the $88K he's getting is all going towards building this "web site." It will be very interesting to see what it looks like when it's done (if ever, and how much it really cost to put up). I think it's no surprise that their 2010/2011 review has a line item labeled "Contributions to Allies" with $0 in both years. They'd never be that obvious, even on their own reports.
  15. Denialgate - Internal Heartland Documents Expose Climate Denial Funding Network
    But ... but ... (splutter) ... isn't it the AGW crowd who have their noses in the trough of a well-funded conspiracy aimed at world domination? The very idea that Anthony Watts might not have the purest scientific motivations is unthinkable. No, all these documents are clearly forgeries put together by The Cabal in order to discredit the work of real scientists, like Watts and Bolt and Monckton and ... and ... everyone in the Tea Party. Hmph! This cannot go unpunished. Time for more of OUR kind of science: lawsuits and FOI claims and email hacking. We'll teach those AGW-conspiracy chappies to toe the line.
  16. Denialgate - Internal Heartland Documents Expose Climate Denial Funding Network
    Hmm, I wonder... will the mainstream media even bother to report this? I'm thinking perhaps most of them wont, unless and until it becomes a big story through the efforts of a few.
  17. Denialgate - Internal Heartland Documents Expose Climate Denial Funding Network
    And they have the gall to accuse climate scientists of being in it for the money!
  18. Denialgate - Internal Heartland Documents Expose Climate Denial Funding Network
    Additional information is posted by John Mashley at the following URL: http://www.desmogblog.com/fake-science-fakexperts-funny-finances-free-tax
  19. Denialgate - Internal Heartland Documents Expose Climate Denial Funding Network
    Stunner #1 - Craig Idso makes a six figure salary from Heartland. Stunning in the large sum of money, and the fact that he's really not that prominent. I don't think Heartland is getting their money's worth on that one!
  20. Climate change policy: Oil's tipping point has passed
    All interesting but still doesnt address the question of would be the cost per kWh of the energy, even when considering just the mining cost alone. The bigger objection is that Kulcinski's reactor is not a demonstration of viability - it needs 3 orders of magnitude more energy than it produces. It shows He3-He3 fusion is possible but not yet that it is practical. I dont think you could regard this as "short term" solution at all. Long term, maybe. Getting off oil isnt really quite so much of the problem. (The price you will pay for it by the end of 2012 will help). Getting off coal is and I think fusion is going to have come a long way very very fast to be competitive in price with that.
  21. Peter Hadfield on Himalayan glacier melt
    andylee @ 29 Thanks for the explanation. I wondered how the ratio became so skewed. Is that a Tea caddy he is shaking, perchance?
  22. Climate change policy: Oil's tipping point has passed
    scaddenp- If sufficient manufacturing infrastructure was built on moon, it is easily conceivable that a rail-gun or coil-gun could launch simple capsules all the way to earth. They would only need a heat-shield, parachutes, and a landing area. - an He-3 reactor uses an electrostatic field to confine the plasma, since the particles are charged. Gerald Kulcinski, a professor at the University of Wisconsin, has built one in his lab. The reason that an industrial scale reactor has never been built is that the only He-3 on earth comes from decaying Tritium i.e. old H-bombs. -Also, I was mistaken when I said that all the known He-3 on the moon would power the global power grid for 1000 years. It would only power the US for that long, and since the US is about 1/4th of the global power supply, the real figure would be 250 years. But, you will frequently see in blogs that the He-3 on the moon is only about a meter deep. This comes from the Apollo core samples only going to down to 1M, and there is no reason to think that it all stops there.
  23. 2000 Years of Climate Reconstructed from Pollen
    Getting away from the details of how surface temperature varies from proxy to instrumental on Greenland, there are three proxy pieces of evidence that splat Camburn's bowhead whales of 1ka idea (let alone St Roch): 1: exposed shorelines round NE Greenland indicate ice-free conditions furthern north than present between c. 8.5-6ka BP (Funder 1989, ref in Polyak et al 2010). 2: Wood in the collapsing remnants of Canadian Arctic ice shelves is several thousand years old, indicating the shelves have been continuously stable for that period of time. 3: Small ice caps in the Canadian Arctic are exposing land not exposed for several thousand years (can't seem to locate refs, if anyone has them feel free to comment or corrent me!). Polyak et al does detail some evidence for summer temperatures in the Arctic being notably warmer than mid-20th Century at some point in the early Holocene, but proxy evidence would indicate that the Arctic has not been this warm for at least about 3,000 years, possibly longer. Since there was a good reason for the Arctic to be relatively warm in the early-mid Holocene (orbital forcing), and given the rapid trajectory of warming we are presently observing, it does not make good news, and we'll soon see the mid-Holocene in the rearview mirror too unless we can change Earth's energy balance.
  24. NASA Mission Takes Stock of Earth's Melting Land Ice
    Note: This will be my last post on this conversation, as it is both off-topic and, in my opinion, settled. Norman - The figures for groundwater depletion definitely have uncertainties. I have seen figures from 0.15 to 0.8mm/year, although the 0.8 you point to is, again, on the upper border. Where you are seriously distorting the data is in not recognizing or incorporating other factors, such as reservoir impoundment, or as Tom Curtis has shown, groundwater replenishment. I'll leave the replenishment portion to Tom Curtis, who has shown a great deal of the data. On impoundment, Church et al 2001 estimate a net water usage contribution of -1.1 to 0.4 mm/yr contribution, with impoundment ~-0.3 (Table 11.8), and Chao et al 2008 show an average rate of impoundment of -0.55 mm/yr. Groundwater mining, on the other hand, has been estimated at 0.2-0.3mm/yr (Vemeer & Rahmstorf 2009) - just about equal to impoundment. So yes, you are cherry-picking, not presenting all of the data. You only once mentioned increases in impoundment, dismissing it offhandedly (when it is of equal scale, and opposite in sign), and have only presented groundwater mining without replenishment. And what's worse, you continue not to recognize your cherry-picking. I no longer have any expectation that you will.
  25. NASA Mission Takes Stock of Earth's Melting Land Ice
    KR @58 "Norman, you continue to present just one side of the picture - and hence you are distorting it." Are you certain of this. You use this one source which uses a super low figure for water depletion that no one else seems to agree with (you can check my previous links on this if you so choose). I am not using one data point (Ogallala aquifier) to make a point. In the links I have posted, they all deal with estimates of global water depletion from aquifiers. Your article would be correct if the water depletion was at the very low value of slightly more than 61 km^3 per year but I have listed more than one source that shows it to me much higher and they are including recharge rates. They have a medium condifence for Groundwater mining even though no other source I linked to is even close to this low level. That is why they do not find any change in SL from water mining. They are using the super low value of 0.25 SLR even though other experts in the field have this number much higher. For irrigation alone the figure was around 245 km^3. Wouldn't it be a "cherry pick" to use just one source of data as your refute of mine and then claim I am wrong, when your data source is considerably lower than other researchers in the same field?
  26. NASA Mission Takes Stock of Earth's Melting Land Ice
    Norman - Let's look at all the data. I'm using Milly 2010 as the reference, rather than the dozens of papers they reviewed. This is the data I pointed Norman to, the data from which he quoted but a single number for a particular, quickly depleting, aquifer. Primary among Norman's omissions is the expansion of reservoir filling - both direct containment and in the rise of local water tables around reservoirs. I invite everyone to view this summary - and compare it to Norman's cherry-picked presentation of just aquifer depletion, just one side of the equation. Groundwater adds to sea levels (as per your reference), but reservoir filling subtracts from it - and they appear to cancel out. Norman, you continue to present just one side of the picture - and hence you are distorting it. --- External constraints - Some uncertainties, for example the recent GRACE data indicates that ice cap contributions may be ~10% lower than previously thought. Table 8.1 Sea-level rise (mm/year) / 1961–2003a / 1993–2003b / 2003–7c 1. Observed / 1.8 ± 0.3 / 3.1 ± 0.4 / 2.5 ± 0.4 2. Thermal expansion / 0.4 ± 0.06 / 1.6 ± 0.25 / 0.35 ± 0.2 3. Glaciers / 0.5 ± 0.1 / 0.8 ± 0.11 / 1.1 ± 0.25 4. Ice sheets / 0.2 ± 0.2 / 0.4 ± 0.2 / 1. ± 0.15 5. Sum of 2 + 3 + 4 / 1.1 ± 0.25 / 2.8 ± 0.35 / 2.45 ± 0.35 Note that this leaves ~0.05mm/yr +/- 0.35 unaccounted for over the last eight years, including the GRACE data. There is very little room for water usage contributions! Now looking that the Milly summary of ground water contributions, excluding cryosphere contributions: Estimated potential contributions of changes in terrestrial water storage to sea-level change during the decade of the 1990s. Trends assigned “medium confidence” are probably of correct sign and order of magnitude. Trends assigned “low confidence” cannot be constrained by available data to be smaller than multiple tenths of a millimeter per year in magnitude, nor are data sufficient to be sure that any of these terms is large enough to be a factor in sea-level rise. “Essentially unidirectional” trends are those whose sign and order of magnitude are probably dominated by decadal and longer timescales, as opposed to interannual variations. Table 8.2 1990s sea-level trend (mm/year) / Essentially unidirectional? Medium confidence Reservoir filling: −0.25 yes Groundwater mining: +0.25 Yes Fifteen largest lakes: +0.1 No Climate-driven change of snow pack, soil water, and shallow groundwater: −0.1 No Atmospheric water storage: −0.05 Yes (under projected warming) Low confidence, but possibly substantial magnitude Irrigation: <0 Yes Dam-affected groundwater: <0 Yes Permafrost thaw and drainage: >0 Yes Lake-affected groundwater: ? No Wetland drainage: >0 Yes Deforestation, urbanization: ? No Low confidence, probably not substantial magnitude Post-glacial desiccation on millennial scale: >0 Yes
  27. Fritz Vahrenholt - Duped on Climate Change
    Ok, thanks Dana.
  28. Fritz Vahrenholt - Duped on Climate Change
    RE - the sun's magnetic field deflects cosmic rays, which hypothetically seed clouds. See the cosmic rays rebuttal.
  29. Fritz Vahrenholt - Duped on Climate Change
    I wonder if this is what he meant... "This is why the sun's magnetic field has continued to weaken since 2000. As a result, this magnetic field doesn't shield us against cosmic radiation quite as well, which in turn leads to stronger cloud formation and, therefore, cooling." I think he means the Earth's magnetic field, right? (which has decreased in the past few years). How would the Sun's magnetic field protect us?
  30. It's methane
    16 - Heircide Have a look at the wedges
  31. NASA Mission Takes Stock of Earth's Melting Land Ice
    Tom Curtis @55 and KR @56 Before you continue to believe my argument to be flawed. Please read this material and remember what I had claimed in Post 21. Maybe you will find my thinking ability is not so poor after all and that I do have a valid point. "Because most of the groundwater released from the aquifers ultimately ends up in the world’s oceans, it is possible to calculate the contribution of groundwater depletion to sea level rise. This turned out to be 0.8 mm per year, which is a surprisingly large amount when compared to the current sea level rise of 3.1 mm per years as estimated by the IPCC. It thus turns out that almost half of the current sea level rise can be explained by expansion of warming sea water, just over one quarter by the melting of glaciers and ice caps and slightly less than one quarter by groundwater depletion. Previous studies have identified groundwater depletion as a possible contribution to sea level rise. However, due to the high uncertainty about the size of its contribution, groundwater depletion is not included in the latest IPCC report. This study confirms with higher certainty that groundwater depletion is indeed a significant factor." source. Please note I stated that groundwater use of aquifiers was close to the same amount of SLR from ice caps and glaciers and this material says the very same thing.
  32. citizenschallenge at 06:46 AM on 15 February 2012
    Climate mythbusting at Lane Cove, Sydney on Feb 28
    Usually I try reading the comments before posting, but Daniel's comment #2 & images had me laughing too much to notice #6 or #9. Well, John Cook if not this event, it is something you should be considering, for future talks and such. cheers
  33. It's methane
    Is there any research into estimating what percent each of the greenhouse gases is due to anthropomorphic activity? If the intent is to stabilize the concentrations of greenhouse gases it would be nice to know how much of an effect our actions have on each molecule. IE is there a study that shows us what policy will give us the most bang for our buck?
  34. citizenschallenge at 06:35 AM on 15 February 2012
    Climate mythbusting at Lane Cove, Sydney on Feb 28
    DMCarey I finished typing out my two sentences before noticing your comment. You beat me to it. John ditto on that video idea... how about it, we don't want to be left out in the cold hehehe just because we're on the other side of the planet.
  35. CO2 is plant food? If only it were so simple
    layzej- "Limiting the search to 2010 onward reduces the results to about 14,000.' Once you start going through them you'll find there are far less than that. I normally go through the first 100 pages of hits. Gives one a very good idea of what the scientific literature says. Time consuming but necessary, if facts are what you are interested in. "The literature appears to be as inconclusive" Nope. All the recent literature finds limited evidence for the CO2 fertilization effect in the 20 the century, and forests that did once benefit during that century, have stopped doing so. Suggesting some sort of threshold, or acclimation, to elevated CO2. Probably what you are doing is looking at the literature without regard to its chronology. "Some find a net gain for specific species" Undoubtedly. Liana for instance, which are woody tropical vines, are growing like crazy. But that's not John Nielsen-Gammon's contention is it? He claims a net global benefit. "One found that approximately 20 percent of sites globally exhibit increasing trends in growth that cannot be attributed to climatic causes" That's undisputed. It has been the subject of considerable scientific debate over the years - whether this might be the consequence of elevated CO2. Trouble is, the latest global forest inventory finds the CO2 is currently going into forest re-growth and is not due to CO2 fertilization. This tallies with recent (last 2 years) studies which find no fertilization effect at a global scale. "showed a large increase in wheat yields for a doubling of CO2" Yes, Dawei's post is well-balanced. The title of it says it all really.
  36. 2000 Years of Climate Reconstructed from Pollen
    Robert Way @25, there are only two issues: 1) Was the original graph so bad that it did not show Camburn's suggested 3 degree over modern Arctic temperatures did not apply to Greenland 9000 years ago. The answer is no. The methodology used by Renowden was poor, hence my caution against over interpreting the graph, but it still represents information about the relationship between the present and the past. Imperfect information is not no information. To put this into perspective, for Camburn's claim to be true of Greenland, modern temperatures would have had to be at or below Easterbrook's claimed "modern temperatures". So, for the original graph to be so bad as to not refute a generalization of the CAA temperatures, Renowden's methodology would have to have been worse than simply taking the 1905 temperature as being the modern (2001-2010) temperature. Whilst Renowden's method certainly requires caveats (which I gave) any argument that requires it to be worse than Easterbrooks (as yours does) is patently absurd. 2) Does the corrected graph not support my argument against Camburn. The yellow line in the corrected graph is the temperature determined as the modern temperature by Kobashi et al, and indicated as such on their graphs. While their methodology may have differed from Alley et al's (the data on the original graph), there data is from a ice core at the same site, so a modern temperature for Kobashi et al, is also the modern temperature for Alley et al. Quite plainly, then indicating the modern temperatures as determined by Kobashi et al is appropriate, and equally plainly it supports my argument. Hence your criticisms have no bearing on the discussion. Like it or not, this is not a scientific paper, and we do not do science in commenting on this blog. It is absurd to expect all the formal requirements of scientific papers to apply to any presentation of information in comments on a blog (not a post, but a comment). It is reasonable to expect us to present as accurate information as we can, and to provide suitable caveats, but I have done exactly that. That, so far as I am concerned, is the end of the matter. If you want to reduce yourself to silence by making the perfect the enemy of the good, by all means go ahead. But I do not have either the time or patience for such folly.
  37. New research from last week 6/2012
    The abrupt 60ppmv rise in CO2 during de-glaciation is interesting. Could this be the reason. http://mtkass.blogspot.co.nz/2011/08/end-of-ice-ages.html
  38. 2000 Years of Climate Reconstructed from Pollen
    Robert Way wrote: "Concludes the rate of change is greater than any time over the last 1200 years but that periods of warmth on the century scale have equaled present." See, this is where phrasing gets dicey. Presumably, what you mean is that the Ljungqvist study found that there were hundred year periods in the past 1200 where the average global temperature anomaly was equal to that of the most recent hundred years. Which, frankly, falls into the category of, 'um, yeah... we knew that already'. However, your statement could also be read as saying that there were hundred year periods in the past 1200 where the average global temperature anomaly was equal to that of the past few years. This seems IMO very likely to be the 'skeptic' take on the study, despite it being completely false. Indeed, there are grounds for such confusion here. Most people generally don't interpret the "present" to mean, 'the past 100 years'.
  39. 2000 Years of Climate Reconstructed from Pollen
    You can't take GISP2 and just tack on thermometers onto them. There's so many processes at play that it just doesn't work. Using a model similar to Kobashi et al (2011, of which Jason Box is a co-author) is a better solution, not perfect but better. GISP2 and Kobashi are also using different proxies but anyways... My issue is with the graph you presented. Whether you're proving a point that you're right about or not, it doesn't warrant using something that is dubious to support your argument. Yes we know that there wasn't thousands of years where temps in the Arctic were significantly above the present (especially 9000 ca BP like Camburn suggests) but the graph presented above has a series of significant issues: (1) The temperature provided as Current Greenland Temperature is not comparable with GISP2 From the author: "The green line represents an estimate of current temperatures in central Greenland. I looked at the nearest station with a 100+ year record in the GISS database (Angmagssalik), and used a Mk 1 eyeball to estimate a 2.5ºC increase over the century (I’d welcome a more accurate estimate, if anyone’s prepared to dig one up). The difference between the green and blue lines is the warming that Easterbrook wants to ignore." -That's just not acceptable. (2) A dot was placed for the 2010 temperature on a graph which is not annually resolved. If annually resolved would the dot stick out as much? no... so why show it? You can't compare an instrumental temperature from one year to GISP2 without a rigorous method (3) Kobashi's paper itself shows that the 2010 temperature was around the average of a few decades over the last 4000 years, yet in the figure shown it is the highest by far over the last 12,000... That isn't true nor is it scientifically accurate. The reason I bring it up is because I think that this is an example of how proponents get themselves in trouble. That's all I was doing. I was not trying to argue with the main point of your conversation but just needed to point out that being right but using faulty evidence does not help anyone. Sorry if I was harsh. Kobashi et al "The estimated average Greenland snow temperature over the past 4000 years was −30.7°C with a standard deviation of 1.0°C and exhibited a long‐term decrease of roughly 1.5°C, which is consistent with earlier studies. The current decadal average surface temperature (2001–2010) at the GISP2 site is −29.9°C. The record indicates that warmer temperatures were the norm in the earlier part of the past 4000 years, including century‐long intervals nearly 1°C warmer than the present decade (2001–2010). Therefore, we conclude that the current decadal mean temperature in Greenland has not exceeded the envelope of natural variability over the past 4000 years, a period that seems to include part of the Holocene Thermal Maximum. Notwithstanding this conclusion, climate models project that if anthropogenic greenhouse gas emissions continue, the Greenland temperature would exceed the natural variability of the past 4000 years sometime before the year 2100." RE: Ljungqvist. I saw this paper a few weeks ago. Interesting stuff. Has the most available proxies out of any study and uses a method superior to Mann's work. Concludes the rate of change is greater than any time over the last 1200 years but that periods of warmth on the century scale have equaled present. Interesting stuff.
  40. Katharine Hayhoe, Intent to Intimidate
    MattJ wrote: "Luther himself did the same thing [i.e. 'completely miss the most fundamental messages in the bible'] when he created Protestantism, and his bad example has been followed by not just Protestants since then." Frankly, I found this statement offensive... and I'm an agnostic. Ironically, 'the Reformation' itself was largely due to perceived instances of failing to follow fundamental biblical messages. Let's please not rehash centuries of Catholic/Protestant bigotry here. also: "I am all too aware that far too few ever do embrace this spiritual struggle" Or, as my muslim friends call it, jihad. and: "raising beef cattle is a large cause of global warming" Not really. Any land use and/or methane release issues are constrained by current total cattle population. There is no cumulative effect in play here, and thus the GW impact is small compared to (for instance) increasing CO2 levels.
  41. 2000 Years of Climate Reconstructed from Pollen
    owl905@13: More (and more recent) about proxy data from Ljungqvist et al.: Northern Hemisphere temperature patterns in the last 12 centuries
  42. NASA Mission Takes Stock of Earth's Melting Land Ice
    Readers - The preceding exchanges with Norman can perhaps be most useful as a demonstration in cherry-picking. When you see someone making an assertion without qualifications, when you see someone base their argument on a single number without looking at or discussing whether that is representative, and (in this particular case) when the single factum presented is an extreme that appears to support their argument, when a more complete look at all of the data demonstrates the opposite: Then - you should suspect cherry-picking. Norman - As I have noted, and as Tom Curtis has so very clearly demonstrated, you have repeatedly selected single numbers from only one side of the water usage mass balance equations, the withdrawal side. And those numbers are extrema, outliers, which you have presented without context or even mention of the averages. All in pursuit of your first, unsupported/unsupportable assertion - claiming that groundwater withdrawal was sufficient to cause sea level rise even without cryosphere melt. That assertion is clearly incorrect when all of the data, including groundwater replenishment and external constraints on the mass balance, is viewed. Your repeated presentations of this flawed argument indicate (IMO) either an inability or unwillingness to actually consider the data, and readers should keep that in mind.
  43. New research from last week 6/2012
    In other non scientific news, the world's driest dessert experiences flooding, it's almost as if the climate is changing or something...
  44. 2000 Years of Climate Reconstructed from Pollen
    Robert Way @22, with respect, the argument being made was:
    "As clearly indicated, by the green line, central Greenland temperatures where not warmer than current temperatures about 9,000 years ago. The green line should not be taken as an exact indicator, based on the methodology used to produce it. But it is accurate enough to show the 3 degree C difference was not universal in the Arctic."
    The argument is clearly about temperatures 9,000 years ago, not over the whole intervening interval. I clearly expressed reservations about the indication of modern temperature, indicated that those reservations where because of the methodology employed, and linked to the report of the methodology so people could make their own assessment. My final conclusion was not even that there was not a period of time thousands of years long in which the Candadian Archipelago was not 3 degrees warmer than modern times, but only that such an episode, if it occurred was not universal. Your criticism seems to me to be for the most part irrelevant as being based on a clear misinterpretation of my argument. And, quite frankly, what little of it which is relevant seems to me to be mere carping. Finally, the graph to which you refer is not "wrong". It correctly shows Easterbrook's claimed modern temperatures. It correctly shows Renowdon's estimate of modern temperatures, and it correctly shows the 2001-2010 average as measured for Kobashi et al, and as shown on their graphs by the black line. By what contortion of illogic you consider the same line shown by Kobashi at al to be appropriate, but inappropriate when it appears on my graph I cannot imagine.
  45. Katharine Hayhoe, Intent to Intimidate
    I see people are waking up to the sad reality that one can be a so-called "bible believing Christian", yet completely miss even the most fundamental and important messages in that book. Some of us, though, figured this out a long time ago. Luther himself did the same thing when he created Protestantism, and his bad example has been followed by not just Protestants since then. Interestingly enough, there IS a connection between the answer to the question (how to avoid falling into that trap of missing the messages) and what the world needs to do to mitigate climate change. For both require the same fundamental approach: to recognize the need for spiritual struggle. Now I know such a statement will cause some readers to spit out their coffee if they happen to be reading while sipping at the same time;) But think about it: raising beef cattle is a large cause of global warming, eating a mainly vegetarian diet (at least for large parts of the year, e.g. Lent/Advent) IS a classic first step in spiritual struggle. So the two coincide here. But it gets better: the only time-tested way to deal with the human tendency we lament here, the tendency to believe what you want to believe (this is what AGW denialists rely on) while ignoring all the facts of the "inconvenient truth" is self-denial wrought by spiritual struggle. Learned discussion in scientific journals has never been enough, even the skillful use of rhetoric (in the best sense of the term) to create and guide a political movement is not enough. Then again, I am all too aware that far too few ever do embrace this spiritual struggle, so many remain in their ignorance. But this is why I keep returning to imagery from that same Book of the Apocalypse mentioned above, warning that we are facing the most stressful time we have ever faced since the beginning of human civilization, as AGW induced famine, war and pestilence spread over the Earth. You can tell I don't place much hope in 'geo-engineering', either.
  46. 2000 Years of Climate Reconstructed from Pollen
    I've lost long comments twice now and I don't have time to write another one. The point about tacking on modern temperatures is about this graph: http://www.skepticalscience.com/pics/GISP2rescaled997.png Which is wrong. The tacking on is not done appropriately and the graph cannot be used to substantiate ones argument because of it. Kobashi et al (2011) which I cited provides a better solution to the issue. We all agree there wasn't millennia of warmer temperatures than present. But in the last 4000 years in Greenland there were at least century long portions which were about a degree warmer than present. My point is that it is not as straightforward as the argument that is being made. Natural variability has been larger in the past than we sometimes talk about and it is important for us to point out the irrelevancy of these past warm periods, not argue about which period was warmer than which. Natural variability or not, you can't escape the physics...
  47. Climate mythbusting at Lane Cove, Sydney on Feb 28
    Should be a good show. Would you consider uploading a video of the event on youtube for those of us who live on the wrong side of the planet?
  48. CO2 is plant food? If only it were so simple
    Rob Painting: No need to rely on trust. You can search for yourself, just limit your search from 2010 onwards ... If you can find any paper that observes a net global benefit from increased CO2 I'd be interested. I haven't found one. Limiting the search to 2010 onward reduces the results to about 14,000. Still more than I can possibly review. I took a look at the first few dozen. The literature appears to be as inconclusive as it is encyclopaedic. Most studies conclude that the future is uncertain. One found considerable increase with mechanistic process-based models but reduced habitat suitability from niche-based models. Some found a net gain for certain local environments. Some find a net gain for specific species. One found that approximately 20 percent of sites globally exhibit increasing trends in growth that cannot be attributed to climatic causes, nitrogen deposition, elevation, or latitude, which we attribute to a direct CO2 fertilization effect. This of course does not mean that 80% are stable or declining, just that the growth could not be attributed to CO2. None of the first few dozen were global in scope and were able to conclude that a net global increase or decrease should be expected. One that was interesting to me (because I don't eat tree's but I do drink beer) showed a large increase in wheat yields for a doubling of CO2: http://www.sciencedirect.com/science/article/pii/S0378377409001991 I think I'm going to have to rely on the IPCC to distill this all down. Regarding SkS overstating things - I never implied that they do. I'm just pointing out that a great deal of credibility and trust can be gained by calling out cases where ones own position is being overstated by others. The source is no longer seen as an advocate for his "side" but is seen as an advocate for the truth.
  49. 2000 Years of Climate Reconstructed from Pollen
    Robert Way @19, With regard to tacking on modern temperatures, I do not know which graph you are referring to, nor to which statement you refer. Never-the-less, appending instrumental temperatures to a graph is necessary if you are going to compare paleo-temperature series with modern temperatures as it is impossible to get proxies extending to the current decade, and even then they need to be compared to instrumental temperatures for validation (and hence for which the instrumental temperatures should be shown). The temperature differences reported by Camburn were for 9000 years before present (see 14 above) and hence cannot be contradicted by Kobashi et al. Further, Camburn was suggesting elevated temperatures for "several thousand years", so a decade or two at that level is not particularly relevant. Given the long time scale Camburn had in mind, the centenial average (green line) is the appropriate comparison. As you can see, it only exceeds modern values occasionally, and never by more than 1 degree C. What is more, my comment about 0.5 to 1 degree specifically addressed Camburn's comment, and hence was also about 9000 years BP. Specifically I was pointing out that if you adjusted Camburn's 3 degrees above modern benchmarked on the 1950s to be benchmarked on the 2000s, it becomes 0.5 to 1 degree above modern (based on the Arctic temperature graph). On a side note it is about 1.5 degrees above modern based on Kobashi et al, but Camburn was not discussing Greenland temperatures so that is not particularly relevant. Finally, your report on Kobashi et al's findings is overstated. Kobashi et al do not show temperatures exceeding modern (2001-2010) plus 3 degrees C at any point over the four thousand years, although twice it comes close. Those two decades are the only occasions the uncertainty interval exceeds modern plus 3, although they do not exceed modern plus 4. It only exceeds modern plus 1 in about 10 of the 400 decades shown. While I appreciate your concern about our interests, I am still perplexed as to why you have taken exception to what I said, beyond some clear examples of your having misunderstood what I said. This is particularly the case as I took care to introduce a caveat about Renowdon's method in 18, and to indicate that the 2010 temperature was not properly comparable with what are effectively decadal averages (although still, I believe of interest, as Sphaerica points out). Given the topic of this thread, Kobashi et al's reconstruction of the last thousand years may be of interest:
  50. Fritz Vahrenholt - Duped on Climate Change
    Good to finally see a journalist being truly skeptical about the "skeptic" claims. What a refreshing change from the unquestioned denier drivel that is allowed into the newspapers and magazines every single day.

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