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Comments 111851 to 111900:

  1. Arctic Sea Ice: Why Do Skeptics Think in Only Two Dimensions?
    Count me in agreement that the volume anomaly chart should be adjusted to show the current minimum anomaly. WRT to the title of this post, skeptics think in 2 dimensions because they never saw the movie. The Yooper
  2. Station drop-off: How many thermometers do you need to take a temperature?
    Crap, just kidding.
  3. Station drop-off: How many thermometers do you need to take a temperature?
    "So to conclude: Independent researchers have shown that there is no truth to the claim that cooling stations were removed, in fact evidence suggests that if these stations were included, warming would be shown to be slightly greater." I believe you meant "that if these stations were included, warming would be shown to be slightly *cooler*."
  4. Berényi Péter at 09:57 AM on 24 August 2010
    The Past and Future of the Greenland Ice Sheet
    I just wanted to stress if both local atmospheric and sea surface temperatures were higher than today during the Holocene Climatic Optimum for thousands of years (they were) and the recent rate of ice loss is still considerably higher than any time after about 10 ka BP, then it is either a short transient ("weather") or there is something else at play here (soot?). In the past two centuries, the Arctic has warmed about 1.6 degrees. Dirty snow caused .5 to 1.5 degrees of warming, or up to 94 percent of the observed change, the scientists determined. 2007 J. Geophys. Res., 112, D11202, doi:10.1029/2006JD008003. Present‐day climate forcing and response from black carbon in snow Flanner, M. G., C. S. Zender, J. T. Randerson, and P. J. Rasch
  5. The Past and Future of the Greenland Ice Sheet
    Berényi Péter at 20:28 PM on 22 August, 2010 On Black Carbon, I agree it is a more soluble problem than CO2, I will assemble some recent references (time permitting), but I believe most papers I have read place Black Carbon as below CO2 in importance. Am I correct in assuming the DMI chart you have shown is extracted somehow from the DMI images and not from the original data? I say this only because I have the data and cannot reproduce your chart. Have you defined melt season using some arbitrary thresholds? In all of my attempts to reproduce your chart, average temperature above 80 degrees N and melt season both show significant positive trends over the DMI measurement period - in agreement with independent temperature measurements from various satellites and published papers on surface records (again I’ll try to dig out references). You can check some of the actual DMI data values using the ERA40 re-analysis series which is virtually identical up to its end date and publicly accessible. I suspect you may not be integrating or averaging to derive your melt season values? You are also aware the near surface air temperature for the Ice cover in the Arctic Summer is constrained to just above melting point?
  6. Pakistan flood: many more will die unless more aid is delivered quickly
    Pete Ridley at 08:06 AM, the impact humans have on changing the landscape is often totally ignored when such disasters are being tied to climate change. Every piece of infrastructure whether buildings, roads, levee banks etc provide obstructions to the natural flow of water. The Mississippi being a good example. It has to be accepted that without any change in the magnitude of ANY weather event, such obstructions are going to magnify the adverse effects of ALL such events. The same with fires, cleared areas and particularly roads through thick forests apart from exposing the immediate surface areas to increased evaporation, provide funnels that allow extra oxygen into areas that in the normal course of events would have had more difficulty sustaining such an inferno, and of course all roads lead to areas of concentrated habitation which themselves provide even more highly combustible fuel also more open to the flow of oxygen in. There is no getting away from the tragedy of those caught by such events, but they should not be used to play with the emotions of others to push what is in many ways a political view.
  7. NASA-GISS: July 2010-- What global warming looks like
    And if you get CO2 higher than a certain value,(450? - pliocene level) then you wont get another ice age. Current rates of warming by any measure are an order of magnitude greater than warming within the ice age cycle.
  8. Berényi Péter at 08:59 AM on 24 August 2010
    What were climate scientists predicting in the 1970s?
    #39 Ned at 05:13 AM on 24 August, 2010 we have a blog comment by BP who sees something in a citation of a 1974 paper by Schneider & Dickinson that contained a reference to another 1974 paper by Schneider & Coakley which in turn referred to a 1967 paper by Manabe that, BP assures us, must imply that the world has actually only warmed by 0.2C No. I just wanted to point out either something was fundamentally wrong with a model leading climate scientists relied on in the mid 1970s or our temperature measurements are flawed. Either ... or. There is no third possibility. It's plain logic. You say it was the model, which assumed constant relative humidity, therefore water vapor and cloud feedbacks increased with increasing temperature. For doubling of the CO2 content this extremely sensitive model had the effect of raising the temperature of the atmosphere by about 2.3°C. Somewhat lower than current estimates, but close enough. Still, this influential one-dimensional model, which produced convincing results and constituted an important step toward the ultimate goal of designing realistic three-dimensional climate models, which was also used to study the radiative properties of the stratosphere providing reasons to reject proposed supersonic transport (SST) airplanes, missed the relation between stratospheric and tropospheric temperature trends by a factor of three. Why? I think we could all learn a lot by having a technically correct answer to this question.
  9. Arctic Sea Ice: Why Do Skeptics Think in Only Two Dimensions?
    "The Northwest passage is officially open." Most depressing opening ceremony in a long time.
  10. The Past and Future of the Greenland Ice Sheet
    Berényi Péter at 20:28 PM on 22 August, 2010 The Simpson 2009 paper you cited is interesting. It presents results from “Huy2”, a complex three-dimensional thermomechanical model of the Greenland ice sheet, which has contraints adjusted for estimates of relative paleo-sea level derived from observations and also revised temperature estimates from the GRIP ice core. It is a revised version of “Huy1” from Huybrechts 2002. One of the conclusions is that early Holocene ice volume (and therefore overall Holocene volume loss to present) was greater than previously suggested, which suggests higher sensitivity of the Greenland ice sheet to temperature changes than previously thought. In this paper the authors state: "The reaction of the ice sheet to the Holocene Thermal Maximum may have produced a margin retreat of up to 80 km across the southwest sector of the ice sheet", and “Our results suggest that remaining discrepancies between the model and the observations are likely associated with non- Greenland ice load, differences between modelled and observed present-day ice elevation around the margin...” The paleo-elevation issue is a problem which Vinther 2009 attempts to address using the d18O values from several ice core sites to back-estimate (from the altitude relationship) -and more accurately constrain- elevation estimates. These results also resolve some previous disparities with bore-hole studies, bringing these proxy results closer. In doing so the results diverge significantly from previous so called “shallow ice approximation” based model results in that the elevation and probable ice thinning has been revised in Vinther 2009 to be greatest during the "Holocene Climactic Optimum", which may be an intuitive result. I have adapted the chart from Simpson 2009 to make it more comparable with that from Vinther 2009 shown later. Figure 1: Ice volume estimates from 3-D ice sheet models Huy 2 (black) and previous Huy 1 (grey), from Simpson 2009. The results from Simpson 2009 in terms of volume changes are of course not directly comparable with elevation changes, but the important result from Vinther is the likelihood of greater elevation (and again probably Ice volume) in the early Holocene, and thus again even greater sensitivity of ice loss to temperature changes. Figure 2: revised elevation from Vinther 2009 (black) vs various 3-D thermomechanical model outputs including Huy 1 (orange) from Vinther 2009. The revisions based on ice core proxy temperatures from the work of Vinther ties in to more recent modeling work ( Stone 2010) which uses much more up to date estimates of ice thickness and bedrock topography (compared with previous work such as Simpson 2009 or Lunt 2009 etc). The results from Stone et al suggest again a higher sensitivity to temperature and therefore greater potential changes in future for given temperature variations and CO2 concentrations than previously predicted (for example in IPCC 2007) As for sea level budget contribution due to melting of the Greenland Ice Sheet, you are correct that Simpson does suggest a relatively low averaged value for the early Holocene, but as suggested above, this is likely to be an underestimate. The most recent IPCC (AR4, 2007) value for Greenlands contribution (based on 1993 to 2003 range) were between between +0.14 to +0.28mm/yr. Updated estimates suggest an increase to +0.46mm/yr for the period 2000 to 2008, van den Broeke 2009, Velicogna, 2009, with estimates for the most recent period as high as +0.75mm/yr . In a recent review Cazanave 2010 gives an average of several recent estimates of Greenland Ice Sheet contribution between 2003 and 2007 of 0.5mm/yr. The Alley 2010 paper Ned cites above also has a pertinent chart of various recent estimates of sea level contributions which show apparent acceleration of loss and recent values well above 0.2mm/yr. There is also corroborating evidence of resultant accelerating North Atlantic (precision GPS measured) uplift in coastal bedrock Jiang 2010. Uncertainties in this uplift, and uncertainties due to the relatively short observation period and also different mass loss derivations from GRACE, are still apparent from some of the differing values (by potential factors of two) of ice mass loss in the recent work to date, as noted by Bromwich 2010 and Sorenson 2010. Nevertheless very recent estimates (published August 2010) trying to account for GPS measured uplift estimates still show large and recently accelerating Greenland ice mass loss, even if the absolute magnitude of these losses is yet to be quantified with precision, see: Khan 2010 and Wu 2010. It should be noted that these estimates are placed in the context of general consistency with data from other sources (with longer measurement periods of the variables used to estimate mass variation), and with updated models. There is little argument that the recent Greenland ice mass loss is highly significant and currently increasing. In summary, this does seem to be rather more than “noise”.
  11. NASA-GISS: July 2010-- What global warming looks like
    Pete Ridley - there are multiple lines of evidence supporting the conclusion that the Earth is warming "at unusual rates". These include sea level rise, ocean heat content, the well supported surface temperature data, the satellite temperature record, growing seasons advancing faster than anything in the record, the paleo data on climate sensitivity to CO2, on and on and on. All of this evidence points in the same direction - "unusual rates" of temperature increase. Unless you can provide solid, repeatable, confirmable data contrary to this conclusion, or have invalidated all the mutually reinforcing evidence supporting AGW, you have not made your case.
  12. There's no empirical evidence
    This may be a rather stupid question given the subject is referred to so often, but I get the impression that at times different people consider it as something different, or perhaps more commonly simply don't know how it is defined and blindly use it. So can someone explain where the Top of the Atmosphere (TOA) is actually located, and why that particular point has been declared as such, and what it would mean if different levels were to be considered the TOA instead.
  13. NASA-GISS: July 2010-- What global warming looks like
    KR, you are seeing a conflict that isn’t there. Between ice ages the globe warms and glaciers retreat then cools and glaciers advance. It’s happened before and will happen again. I repeat (but read the words carefully) “There is clearly no basis for the claims that the Earth has warmed at unusual rates in recent times...” most importantly those words “at unusual rates”. Best regards, Pete Ridley
  14. Pakistan flood: many more will die unless more aid is delivered quickly
    Anne-Marie, don’t overlook the fact that a major contribution to the extent of the catastrophe arising from this weather event in Pakistanis is not so much due to an extraordinary monsoon as to the manner in which the river(s) are being managed and the manner in which people are populating unsuitable areas. Dappledwater, there is enormous uncertainty about future changes to global climates and whether the globe will get hotter or colder. There is no convincing evidence that “these extremes will become common place in the not too distant future”. Kernos chooses to give the impression that we know that “humans are causing climate change by increasing CO2 and other greenhouse gasses into the atmosphere” but he is wrong. We do not know this, we speculate about it. From what he says he must be quite happy to volunteer to be one of those “few million (who he considers) will not make much difference”. I tend to agree with CBDunkerson. Best regards, Pete Ridley
  15. Medieval Warm Period: rhetoric vs science
    Correction: the original post and several of the comments refer to "Moburg". It should be "Moberg" (as used in later comments).
  16. There's no empirical evidence
    Energy tracking is discussed here and excellent relevant discussion of the Trenberth & Kiehl diagram here And as for claiming there is no flaws in 107-110. Well we tried to help. I cant even parse what you are trying to say nor could Ian. We've pointed you to a correct interpretation. I give up.
    Moderator Response: Yes, theendisfar, if you want to post your version of an energy flow diagram, do it on that thread, not this one.
  17. Can't We At Least Agree That There Is No Consensus?
    batsvensson at 06:05 AM on 24 August, 2010 "A "balance of evidence" or the "holistic view" consist of the evidence, that a) climate model shows that CO2 is the only thing that we can think of that can reproduce the current warming trend in conjunction with that b) no other credible cause has been identified. A "consensus" in climate science is an interpretation of, or a conclusion from, evidence that fits into the theory in such way that it helps explain observations with out contradicting any part of the theory." Those are unnecessarily cumbersome definitions batsvennson. Remember that words/definitions are shorthand signifiers for the things they describe. They are not the thing itself, and are used to communicate ideas and information. If we’re interested in what climate scientists consider to be the case concerning a specific issue (say the origin of increasing atmospheric [CO2]), then we might be happy to know that there is an essentially overwhelming consensus that the rise in [CO2] is a result of anthropogenic oxidation of fossil fuels. However we may be interested in the origin of this consensus and then we would wish to consider the evidence. This is pretty obvious if one considers real world examples that we might encounter on a personal level. If you return to the doctor following tests to examine the cause of deep chest pains combined with fatigue and recurrent bouts of bronchitis, and he tells you that (a) the balance of evidence indicates lung cancer, and (b) that he’s sent your X-rays to 6 specialist lung cancer oncologists, and had your tissue biopsies examined by three oncology labs, and that the consensus is that you have got lung cancer, you’d most likely take his views seriously. However, most likely you’d wish to see the evidence for yourself. Now I would say that the notions of “balance of evidence” and “consensus” in this example are essentially the same as when used in climate science, or indeed any scientific subject. I wouldn’t say that “consensus” is used when there isn’t “hard evidence”. Of course it depends what you mean by “hard evidence”! I would say it’s more likely to be used when there is strong evidence, but this evidence may not be immediately communicable to a layman. The term “consensus” is also used when a subject is reviewed to address the evidence base and the interpretations that are drawn from this. So going back to your definitions reproduced at the top of my post, “balance of evidence” has nothing necessarily to do with climate models, or things we can think of, and “consensus” has nothing necessarily to do with any particular theory. In climate science an interpretation based on the “balance of evidence” is something like: “an interpretation that considers all of the evidence that bears on a subject, and which is supported by each of these, not contradicted by any evidence at hand, and more strongly supported than other possible interpretations”. And a “consensus” is something like: “a strongly dominant expert interpretation based on a well-informed and thorough examination of the evidence”. There’s no reason why a consensus need support a theory, although if it doesn’t, there’s obviously strong grounds for considering the usefulness of the theory!
  18. Arctic Sea Ice: Why Do Skeptics Think in Only Two Dimensions?
    Anyone wanting to see the open passage can look here: http://arctic.atmos.uiuc.edu/cryosphere/NEWIMAGES/arctic.seaice.color.000.png
  19. Can't We At Least Agree That There Is No Consensus?
    "It [Consensus] refers to an expert interpretation based on a well-informed assessment of the evidence that bears on a particular issue." I recall an incident when I did my military service as a kid, we was training in doing visual range observations, and the Lt. asked use about the range to various object in the terrain. One guy started out "I guess...", the Lt. immediately interrupted and roared "Hold! We never guess - we estimating distance. Continue... ".
  20. What caused early 20th Century warming?
    #34: "With no other 'anthropogenic' forcings in 1750AD - and excluding volcanic effects, was the Earth warming or cooling in 1750 - or was it in 'balance'?" Based on data presented here, it appears that 1750 was slowly warming. Looking at the rising peaks on the sunspot graphs above and extrapolating TSI backwards to match (if that's a legitimate thing to do), that would suggest TSI was gradually increasing as well, albeit on a shorter period. Does the quantitative aspect of your question suggest that you feel earth temperature should match solar irradiance - volcanic effects exactly? If the 'natural climate cycle' is one that slowly oscillates on its own, what is the value of equilibrium, other than as a midpoint of the normal oscillations? Isn't it more significant to understand what causes the departure from that equilibrium condition?
  21. The main culprit in mid-century cooling
    I have posted a rebuttal to http://www.spinonthat.com/CO2.html in this thread.
  22. Medieval Warm Period: rhetoric vs science
    "That's a difference many seem to forget: the big-picture rate of change of recent temperature anomalies is much too fast to be 'natural'. " YES. And it is linked to ever growing CO2 concentrations resulting from increasing industrial activity relying on coal fired power stations (and massive volumes of cars). This blind spot about recent temperature rise always stuns me. If we had, a few hundred years ago, decided, as a planet, that we would only industrialise using renewable energy, and had kept CO2 constant, and we had still seen a slow rise in temps in recent times comparable to the MWP then, while we might be curious about the underlying mechanisms, and might also be concerned about the effects of a temp rise on a planet of 9 billion people instead of a few hundred million, we wouldn't be concerned about the longer term prognosis of temperature rise. That deniers don't appear to recognise that we are not in that latter fantasy scenario is evidence of a rigid mindset determined to prevent any action to save this little planet.
  23. Greenhouse effect has been falsified
    In this thread user miekol is asked by the moderator to post a question about this article in this thread. I thought I'd "jump the gun" and post a rebuttal now! The article states that O2 and N2 are, despite claims by "warmists", Infra-red active and links to some IR plots. These plots are, in fact all due to molecules made up of different isotopes. Thus there are plots for 16O-17O, 16O-18O and 17O-18O and one for 14N-15N, but none for the symmetric counterparts. Note that for some of the plots the isotope details have been removed. Because these isotopic variants are very nearly symmetric, the absorption is weak (see the very small numbers on the vertical axis). So these isotopic variants make up a tiny percentage of the gases, and the small percentage that do absorb only very weakly. Moreover the O2 and N2 absorptions don't match the frequencies that earth emits at, so there is nothing in "earth-light" for these gases to absorb. Later in the page they state that because O2 and N2 melt at a lower temperature, they are "most sensitive to heat absorption". This is completely incorrect. The melting points of substances relate to the strength of the forces between molecules, which ultimately comes down to the distribution of positive and negatives charges within the molecule. H2O has a negative "end" (the Oxygen) and a positive "end" (the Hydrogen) and this makes a powerful attachment between the molecules. Symmetric molecules like O2 have much weaker attractions and so take less energy to melt and vapourise
  24. Can't We At Least Agree That There Is No Consensus?
    No, batsvensson, consensus is not invoked only in the absence of hard evidence. Scientific consensus is used constantly, even when there is "hard evidence." Consensus is needed to determine whether purportedly "hard" evidence really is hard. No matter how "hard" it seems to be. For more reading on the role of consensus in science, click the links in this comment of mine.
  25. Medieval Warm Period: rhetoric vs science
    The graph shown above (Figure 1) is remarkable. The data are available in the download link on this page. Moberg provides a low frequency component (labeled LF in the data file). It really didn't appear to be that low, so I created a really long period filter and plotted the original data, Moberg's LF (pink) and the long period curve (dark purple) in the graph below. Click for full size Moberg's data ended in 1979. Tacked on to the end is GISSTemp from that point forward (red), adjusted slightly down to merge. This really puts the MWP and LIA into perspective: Yes, there is an underlying long term 'natural cycle', with an apparent period of 1100 years. And yes, we started on the long, gradual upswing after 1650 or so. But the graph of temperature anomalies from 1850-2009 looks nothing like the natural cycle. That's a difference many seem to forget: the big-picture rate of change of recent temperature anomalies is much too fast to be 'natural'.
  26. NASA-GISS: July 2010-- What global warming looks like
    Pete Ridley, others - As an additional note on this thread, which is also relevant to the Are surface temperature records reliable: I wrote this a while back on the topic of proof and disproof. You cannot disprove global warming by pointing out what you perceive as flaws in individual lines of evidence. That only impacts that line of evidence, not the theory. If you want to disprove global warming, you need solid, reproducible data contradictory to global warming - and I've seen nothing of the sort. If John O’Sullivan or Charles Anderson have something worth saying (I read their articles, and I haven't seen any evidence of that yet), they should write it up along with their data for a peer-reviewed publication. Not blogs.
  27. Can't We At Least Agree That There Is No Consensus?
    chris, at 05:31 AM on 24 August, 2010 ok, thank you, my current understanding is that the concept of a consensus is invoked when there is no hard evidence (i.e. observations) to point at and that it is used losely (maybe even to losely) in many different context. That is, it nobody knows what it means until it gets defined.
  28. Can't We At Least Agree That There Is No Consensus?
    In 1995 IPCC wrote: "Any claims of positive detection of significant climate changes are likely to remain controversial until uncertainties in the total natural variability of the climate system is reduced." and "No study to date has positively attributed all parts or parts of observed climate changes to anthropogenic causes." This has been changed to "The balance of evidence suggest a discernable human influence of climate". Another way to put "balance of evidence" it to say "holistic view" which is a phrase that is in popular use at skepticalscience.com - or at least was until it was replaced with consensus. Now, I don’t have a problem with people using all kinds words in any kind of ways as long as it can be precisely define what it is meant with the usage. Since no clear definition exists of these phrases I would like suggest such a definition in two step manner: A "balance of evidence" or the "holistic view" consist of the evidence, that a) climate model shows that CO2 is the only thing that we can think of that can reproduce the current warming trend in conjunction with that b) no other credible cause has been identified. A "consensus" in climate science is an interpretation of, or a conclusion from, evidence that fits into the theory in such way that it helps explain observations with out contradicting any part of the theory. I suggest a definition similar to this because I dont like the idea of every researcher "agreeing with each other". The definition at least leave it open for research to fully hearted disagree with each other with out causing a consensus to be false.
  29. Pakistan flood: many more will die unless more aid is delivered quickly
    "As someone who has far more expertise about weather than anyone here says ... Interview with forecaster Piers Corbyn” Good to see people maintaining a sense of humour in the face of these catastrophic events. The Disasters Emergency Committee is a great way of donating in the UK.
  30. Can't We At Least Agree That There Is No Consensus?
    batsvensson at 05:12 AM on 24 August, 2010 Your first point is correct. One needs to be explicit about exactly what one is referring to in relation to any particular consensus. "And again I repeat my question – by who (and when) was "consensus" introduced in science?" Consensus is an obvious and straightforward concept with a very long history. One only needs to refer to the scientific literature of the 20th century to see this. It refers to an expert interpretation based on a well-informed assessment of the evidence that bears on a particular issue. For example: Hoffmann E (1913) Contagious period of syphilis and the consensus in light of new research DEUTSCHE MEDIZINISCHE WOCHENSCHRIFT 39,14-17 Watson JB, Lashley KS (1920) A consensus of medical opinion upon questions relating to sex education and venereal disease campaigns MENTAL HYGIENE 4, 769-847. ....and 1000's of other papers that address various specified consensus's during the last 100 years of scientific enquiry....
  31. Pakistan flood: many more will die unless more aid is delivered quickly
    "So no, killing off a million Pakistani farmers doesn't help stop global warming at all." Just as I said, but killing off a few thousand million would.
  32. What were climate scientists predicting in the 1970s?
    Let's see, on the one hand we have actual data from three different sources (surface stations, infrared measurements of SST, and microwave radiometers) that all tell us the world has warmed by about 0.6C in the past three decades. On the other hand, we have a blog comment by BP who sees something in a citation of a 1974 paper by Schneider & Dickinson that contained a reference to another 1974 paper by Schneider & Coakley which in turn referred to a 1967 paper by Manabe that, BP assures us, must imply that the world has actually only warmed by 0.2C. Righto, I'll put that on my list of things to look into. :-)
  33. Can't We At Least Agree That There Is No Consensus?
    The problem with the word consensus is that nobody knows what it is a consensus about unless precisely defined. Is it 1) "CO2 operates as a green house gas" , 2) "man made CO2 causes global mean temperature to increase" or 3) "in 2100 sea levels is predicted to be NN meter high", etc, etc. Is there a consensus about all of it, most of it, some of it, or what? Doing a (scientific) literature search definitely not strange the idea of a consensus of all of it (and that make me confident they actually are doing science research else I would ask what kind of science climate science was...) I would say we have "consensuses" about 1) as this can be validated by observation (i.e. is confirmable), and very good reason to believe 2), however the last one. 3) is a more slippery one, this is not based on any observation but model predictions, and therefore it can not be a scientific statement, even less a scientific conlusion, and absolutely not a scientific consensus. (Whether these model prediction is made on super computers with climate models or some calculations made by hand based on some field observations doesn't matter – they are still unobserved predictions). I also acknowledge the fact that it is not pedagogical possible to try to explain for some of the audience why this is as long the ideas remains that predicting future climate is in principle the same thing as calculating planet orbits. And again I repeat my question – by who (and when) was "consensus" introduced in science?
  34. Medieval Warm Period: rhetoric vs science
    The use of the phrase "faulty notion based on rhetoric" is itself a faulty notion, and one based on a misunderstanding of the meaning of the word 'rhetoric'. The phrase would make much more sense if it read, "faulty notion based on empty rhetoric'. Not all rhetoric is empty, after all.
  35. Arctic Sea Ice: Why Do Skeptics Think in Only Two Dimensions?
    Yes, keep the post in the context in which it was written by using absolute dates. Not only is the NW Passage open, but so is the Northern Passage (the other side of the Arctic Basin). The Russkies just passed a 100,000 ton tanker through it with icebreaker support, while there's a norwegian team trying to circumnavigate the arctic. They've already passed through the narrowest point (from the ice cap to land) and are working their way over to the NW Passage, and barring mishaps should get there in plenty of time to sail through it before it begins to refreeze. That would be a first ...
  36. Eric (skeptic) at 03:43 AM on 24 August 2010
    Weather vs Climate: Watch the waves, miss the turning of the tides
    The UHI effect on record temperatures is very real, see http://www.hindawi.com/journals/amet/2010/230365.html for example. I read a study a few years ago (unfortunately cannot locate) where the author did consider the UHIE and determined that the upward trend in high temperature records was larger than could be accounted for by UHIE (that made sense to me). My question is to what extent the chart in the head post is affected by UHIE. The author did not mention it in his paper.
  37. Berényi Péter at 02:20 AM on 24 August 2010
    What were climate scientists predicting in the 1970s?
    #37 Ned at 01:30 AM on 24 August, 2010 0.2 C warming since 1979 also is inconsistent with other land surface temperature data sets, with thermal infrared satellite measurements of sea surface temperatures, and with the microwave lower troposphere temperature trends. Do you mean the radiative convective model of Manabe and Wetherald Schneider and Dickinson based their 1974 understanding of the climate system was faulty? Exactly what made it off the mark by a factor of 3?
  38. There's no empirical evidence
    No, theendisfar, please do not complicate the discussion. Just answer my most recent question first, with a simple answer.
  39. There's no empirical evidence
    Not sure if the post is closed or just taking some time to update, but I believe I have an exercise that will help clear things up. Let's follow the energy. From the Sun to the Earth's surface and back out to space. Toma et al seem to think that where energy is a particular time is irrelevant. Let's follow the energy and see.
  40. Arctic Sea Ice: Why Do Skeptics Think in Only Two Dimensions?
    I'd agree that date wording should be absolute rather than relative (e.g. 'August 2010' rather than 'this month'), but including the latest data and studies in the 'Basic' versions would seem to make them more precise than the 'detailed' copies in some cases. Thus, I'd suggest keeping the same charts and references until it is possible to update all copies.
  41. What were climate scientists predicting in the 1970s?
    Berényi Péter writes: That translates to 0.195°C warming of the troposphere since 1979. Unfortunately it is inconsistent with the GISS Surface Temperature Analysis which shows about 0.6°C for the same period. 0.2 C warming since 1979 also is inconsistent with other land surface temperature data sets, with thermal infrared satellite measurements of sea surface temperatures, and with the microwave lower troposphere temperature trends.
  42. Medieval Warm Period: rhetoric vs science
    fydijkstra writes: On the basis of Loehle's reconstruction we must conclude that the medieval period very likely was hotter than today, as was the Roman period and the earlier Holocene optimum. "Today" in the Loehle reconstruction isn't actually "today", it's 1935 or so. As you can see, things have warmed quite a bit since then: Figure 2: Loehle 2008 temperature reconstruction with Hadley instrumental record. Aside from that, the Loehle reconstruction is really only a northern-hemisphere reconstruction (only a handful of SH proxies were included, as discussed by chris in this comment). If you compare current NH temperatures to Loehle's reconstruction, things are quite a bit warmer now than at any previous time.
  43. Pakistan flood: many more will die unless more aid is delivered quickly
    Kernos, global warming is not tied to population growth. Think about it. Where do you see high population growth? In poor areas with limited technology. Where do you see high CO2 emissions? In wealthy areas where population is generally stable. So no, killing off a million Pakistani farmers doesn't help stop global warming at all.
  44. Medieval Warm Period: rhetoric vs science
    fydijkstra, You are absolutely incorrect about the Moburg reconstruction. The Moburg reconstruction uses low-resolution proxies to do the heavy lifting and uses tree rings for only interannual variations. It was in fact criticized for not using tree-ring data enough by some dendro guys. They said it showed too much low frequency changes because of it. Moburg (2008) shows they were wrong. By the way, for the record. You have been proven wrong. You said it relies on tree rings. It doesn't. That's the novelty of this reconstruction. Craig Loehle's reconstruction is a very poor quality reconstruction. He does not do any weighting based upon area which invalidates his study right off the bat. Also Loehle mis-dates several of his proxies. Loehle made a multitude of errors with his proxy selection, calibration and validation. These are all discussed here: http://www.realclimate.org/index.php/archives/2007/12/past-reconstructions/ and here: http://web.archive.org/web/20071226051459/http://thatstrangeweather.blogspot.com/2007/11/loehle-reconstruction.html Energy and Environment is a crappy magazine (I won't even call it a journal)and the fact that they selected Loehle's original analysis is proof of that. Not even a map showing where the proxies were, let alone the obvious problems mentioned above. To call it the best reconstruction shows you obvious bias and lack of caring for the methodologies employed. You only support the reconstruction which follows your conclusion rather than the one which has the correct methodologies and proxies. It is a farce of you to sit here and say loehle is the best when it has so many glaring flaws. Even Climate audit admitted to many of them.
  45. Berényi Péter at 01:22 AM on 24 August 2010
    What were climate scientists predicting in the 1970s?
    If you want to get a fair picture of where climate science stood in the 1970s, you should read this brilliant paper. There was not much progress in basic theoretical understanding of the climate system since then. REVIEWS OF GEOPHYSICS, VOL. 12, NO. 3, PP. 447-493, 1974 doi:10.1029/RG012i003p00447 Climate modeling Stephen H. Schneider & Robert E. Dickinson On page 487 they write: "The stratosphere couples to the troposphere through radiation and dynamic processes. For example, the radiative convective model of Manabe and Wetheraid shows that changes in stratospheric temperature (because of perturbations in the concentration of water vapor or carbon dioxide (CO2) concentrations) are generally accompanied by smaller (about one-fifth as large) tropospheric temperature changes of opposite sign [Schneidear and Coakley, 1974]." Right. Fortunately we happen to know stratospheric temperatures fairly well since 1979, because they can be derived from satellite microwave measurements performed in a single narrow bandwidth channel. It is RSS channel TLS (Temperature Lower Stratosphere, MSU 4 [57,950 MHz, bandwidth 220 MHz] and AMSU 9 [57,290.344 MHz, bandwidth 330 MHz]). As lower atmosphere is pretty opaque in this frequency band and high up, where it gets thin enough to gradually become transparent, there is not much stuff between the uppermost "visible" layer (it's lower stratosphere, about 17 km high) and the satellite, one does not need a sophisticated computational model with input from multiple sources to derive proper temperatures from radiance data. Therefore I can believe satellite temperature history reconstruction for this particular layer (for lower layers it gets rather complicated). The effect of two large volcanic eruptions (El Chichón, 1982 and Pinatubo, 1991) are clearly visible. They make the Stratosphere warmer (and the surface cooler, as Schneider 1974 states). There is a slight cooling trend in this 31 year long record, although discounting eruptions, it is probably less pronounced than indicated in the figure (-0.314 K/decade). It is also quite interesting, that the decrease occurs in a step-like fashion, with steps coincident with eruptions, but being fairly constant in between, even increasing slightly. It suggests some connection between volcanic activity and stratospheric cooling. There may be an overshoot in the response function with a long relaxation time. Anyway, according to Schneider 1974, whatever caused the stratospheric temperature drop, it is accompanied by smaller (about one-fifth as large) tropospheric temperature changes of opposite sign. Therefore the troposphere must have warmed at a 0.0628 K/decade rate during this time. That translates to 0.195°C warming of the troposphere since 1979. Unfortunately it is inconsistent with the GISS Surface Temperature Analysis which shows about 0.6°C for the same period.
  46. Medieval Warm Period: rhetoric vs science
    fydijkstra wrote : "The fact that this reconstruction was rejected by GRL does not mean that it is a poor analysis. It only demonstrates that GRL is not yet open for paradigm breaking views like Energy and Environment is." I saw no facts in that sentence of yours there : only conspiracy theories, accusation of bias and dishonesty, and laughable belief concerning E & E. Let me remind you what the editor of E & E, Sonja Boehmer-Christiansen, has to say about her pet project : "I'm following my political agenda -- a bit, anyway," she says. "But isn't that the right of the editor?" Funny how so-called skeptics see conspiracy and bias everywhere, except when it is actually stated by organisations they need to believe in. Political posturing has no part to play in science, so E & E fails as a pertinent, relevant, reliable source of any sort of legitimate science.
  47. There's no empirical evidence
    theendisfar, the only part of your reply that addressed my question was "What you seem to be saying is that the imbalance only has a Radiative means to work itself out. Completely true for the entire system." My question was specifically about the entire system--the overall balance of energy, analogous to the overall balance of money in a bank account. That is the point of the section titled "The planet is accumulating heat" in the post at the top of this page. Look at Figure 4. Ignore the breakdown of where that heat is distributed. The top of the curve, showing the total, is what is relevant here. Greenhouse gases cause that accumulation of energy in the entire system by blocking the escape of radiation energy to space, thereby causing that imbalance of energy-in-from-space versus energy-out-to-space. You seem to agree with that, as well. That is the greenhouse gas effect. So you do not really think the greenhouse gas effect is "silly." Your agreement on those points about the entire system, makes me suspect that your disagreement really is only about how that extra accumulated energy is distributed within the system. Am I correct?
  48. Weather vs Climate: Watch the waves, miss the turning of the tides
    Muoncounter, nice graph. I used the same data to run the numbers for 'hottest winter' and found similar results; New record high Winter anomalies were set in: 1882, 1889, 1901, 1914, 1926, 1944, 1980, 1981, 1983, 1988, 1995, 1998, 2002, and 2007. The data clearly indicate that new global record highs are being set with increasing frequency while there hasn't been a new global record low in nearly a century. As to UHI. No study showing that it has skewed temperature records has ever even been WRITTEN... let alone then stood up to scrutiny. Numerous studies of satellite, proxy, and non-urban temperature records have all shown results consistent with the established temperature series. In short, about the only thing which the UHI argument brings to the table is an easy way to identify people who are willing to take a claim with no substantiating data whatsoever as an excuse to ignore overwhelming evidence to the contrary.
  49. There's no empirical evidence
    I've often spoke about the dangers of Averages when trying to describe a system. Where temperature is at a particular point and time is why there is such a thing as temperature. Same thing for pressure. If you averaged everything out then there is no need to measure it.
    I love this paragraph. No idea what it means but I love it because of that. I suggest reading it out loud. The capitalization of Averages is genius
  50. Pakistan flood: many more will die unless more aid is delivered quickly
    One does not hear much about over-population, or population control today. It almost seem politically incorrect to even mention it. What research has been done on these questions? Why don't we talk about them any more? If we do not take care of nature, nature will take care of us. _______ BTW, I am asking questions, not saying what I will do for suffering people. My emotional reactions are locked in. That's not to say emotional paradigm shifts may not be best for the young and future generations.

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