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Comments 73251 to 73300:

  1. Increasing CO2 has little to no effect
    Alleycat#87: "in the past the climate changed without any human intervention whatsoever." No one disputes that. However, this time around we have intervened and the climate is changing, in large part because of that sudden and unprecedented intervention. Using the 'its changed before' argument begs two questions: Do we know what caused climate change in the past? Answer: mostly yes. Do we know if those same mechanisms are making climate change now? Answer: We know very well they are not. Let's use an analogy: The last time your house burned down, it was due to a lightning strike, an entirely natural cause. Does that mean that an arsonist can't burn it down the next time? Does that mean you shouldn't be concerned when you see smoke coming out of the attic?
  2. Increasing CO2 has little to no effect
    Alleycat @88, You really do not seem to understand the science behind climate change and the theory of AGW, and that is confusing you. Also, no reputable climate scientist are claiming that ALL the observed warming is due to increased GHGs from burning fossil fuels and land use change. Nor do the IPCC assessment reports make that claim. As for fingerprints indicating that the warming is because of an enhanced greenhouse effect, well they are everywhere (follow the link below for more information). [Source]
  3. Michaels Mischief #3: Warming Island
    With regard to the discussion of microclimates, Box, 2002 is a comprehensive discussion of Greenland temperature records. Most germane to this discussion is that he list the correlations between certain temperature stations, including Tasiilaq/Angmagssalik (65.6 N 37.6 W), whose temperature record Michaels reproduced, and Danmarkshavn (76.8 N 18.7 W). Danmarkshavn is approximately half the distance from Warming Island, compared to Angmagssalik, and importantly, is subject to the same ice stream, while Angmagssalik is not. This is probably the reason for the poor correlation between Danmarkshavn and Angmagssalik temperatures, reported by Box as being 0.28. That is about half of the correlation normally expected at those latitudes. Given that low correlation, and given that Danmarkshavn is both closer and geographically more similar than Angmagssalik, there is no question that it is the preferable station from which to make an estimate of temperature trends at Warming Island. So here it is: And for comparison, Angmagssalik: Comparing them, there is no question that in Danmarkshavn, the temperature was cooler in the 1950's relative to the 2000's than was the case in Angmagssalik. 1956 is an exceptional year, and the second warmest on record. However, no other year in the 1950's or 60's is warmer than any year in the 2000's except 2008 and 2009. Given that it takes more than one year's warmth to bring about substantial melting, had Michaels used the Danmarkshavn temperature record (as readily available to him as to me), it would have weakened the apparent strength of his case. That, of course, raises the question as to why did he use Angmagssalik? Was it that he, having decided he was expert enough to contradict an Arctic explorer like Schmidt, was not expert enough to be aware of Box, 2002? Or that having decided to weigh in on an issue in the national media, he could not trouble himself to undertake even the limited research I undertake for a blog comment? Or was it deliberate cherry picking? No answer is creditable, and I can see no other option. For completeness: Dana (@13 above) shows the Jan Mayen temperature record, indicating is as the closest to Warming Island. Although it is the closest moderately complete record, it is also in the middle of the Arctic Ocean, and has not in recent times been connected to Warming Island by an ice bridge even in winter. Therefore we cannot assume a significant correlation between Warming Island and Jan Mayen Temperatures. There are two other records available at GIS that are both on the coast of Greenland, and closer than Jan Mayen. They are Myggbukta and Kap Tobin. Unfortunately neither is complete enough to allow direct comparison between the 1950's and the 2000's.
  4. Increasing CO2 has little to no effect
    Sorry guys, but I remain skeptical. Not denying that the climate is changing, but I am skeptical that it is 100% man made.
  5. Increasing CO2 has little to no effect
    I watched Dr. Alley's speech and it seems to suggest that in the past the climate changed without any human intervention whatsoever. Very interesting stuff but it doesn't do anything to point a finger at man as the cause. I really hate the term "climate denier", it says to me that someone has made up their mind and their is no room for debate. In fact none of this is carved in stone and we're still figuring it out. I have to quote the article "So skeptics are right in saying that water vapor is the dominant greenhouse gas. What they don't mention is that the water vapor feedback loop actually makes temperature changes caused by CO2 even bigger." The fact is that water vapor IS the dominant greenhouse gas, and if all this happened many times before man entered the picture, that says to me that we are not the problem and that this is a natural process. Just because it might not end well for man doesn't mean it's our fault.
  6. Between St. Roch and a cold place
    Agnostic: it's hard to say, but extrapolating the trend points at sometime before 2030, and possibly before 2020. It depends on the weather being favourable for ice melt - which is why 2011 raised so many eyebrows. It came within a whisker of beating 2007 by all measures (and did beat it on some), but unlike 2007, the weather wasn't good for ice melt & compaction. It also depends on what you mean by "ice free". A lot of people consider "less than 1 million km2 of ice" to be effectively ice free, but I'm sure the 'sceptics' will claim that, so long as there's one ice cube's worth, it's not "ice free"...
  7. Between St. Roch and a cold place
    The graphic from the University of Bremen says it all. How long before the Arctic is ice free in summer?
  8. Michaels Mischief #3: Warming Island
    Now that there has been some discussion, I would like to sum up my case for SkS readers as a judge might sum up a case for the benefit of a jury. The facts: Greenland is a very large island covered with a single great ice sheet and many regional ice caps. An overwhelming majority of climate scientists assert that the ice sheet and the ice caps are shrinking, supporting this with real evidence from accumulated data, photographs and satellite images. In 2005 Dennis Schmitt announced his discovery that the shrinking ice has revealed that a part of Liverpool Land formerly thought to be a cape was actually an island: this assertion was supported by photographic evidence. Schmitt asserted that he had visited the region by land 10 years earlier at which time the cape was not seen to be an island: this assertion is supported by the record of satellite images. In 2008 Patrick Michaels was shown a book of photographs (Arctic Riviera, Ernst Hofer, 1957) by his friend Paul C. Knappenberger; in Michaels' opinion the map of Greenland found in that book showed that the new island already existed as such in 1957; in Michaels' opinion a temperature series from a weather station 800km distant supports his opinion about the 1957 map; in subsequent comments Michaels has referred to maps of the island in the plural but has never demonstrated the existence of more than one map. The article which Michaels wrote in 2008 has been cited by various bloggers and commenters, some of whom have asserted, or have used words to the effect, that Dennis Schmitt lied about his discovery. Dennis Schmitt in 2008 rebutted Michaels assertions citing inter alia the prevalence of fog in the relevant region. It is a notorious fact that fog is of frequent occurrence in the Arctic and especially along the relevant coastal area. Michaels has presented no evidence whatsoever to show that the map in question is based on accessible scientific data or was produced by a known cartographer or was intended by the author Ernst Hofer or his publisher to be taken generally as an accurate map or specifically as an indication of the existence of a new island. It is clear from the context in which the GISS data is used by Michaels that the intention is to persuade the viewer to infer - from the short term interannual variations in temperature at a far distant location within a fjord - a virtually identical series of interannual variations in temperature in the exposed coastal region of the new island. The width and southern extent of the ice stream which affects that coast varies from year to year and has a very strong influence on coastal temperatures, as noted in 1822 when William Scoresby Junior first described that ice stream in a scientific manner. More evidence needed: Michaels has made an assertion which needs to be proven. He has asserted that maps - plural - exist which support his ideas. It is not for scientists to provide his evidence for him: he, not they, must perform the necessary cartographic research. Michaels may wish to purchase one of the very many maps produced by Ernst Hofer's employer: Lauge Koch, if he can find one of these accurate and data-backed maps to support his hypothesis. If the regional ice cap and glaciers had in fact retreated sufficiently to reveal the width of water shown in the 1957 map, then it is for Michaels to furnish evidence of e.g. precipitation to show that glacial ice had grown back by 1985 to the extent shown in the satellite image from that year. Michaels must furnish evidence in rebuttal of Ernst Hofer's relevant statements in his book to the effect that: summer temperatures within fjords are generally much warmer than temperatures on coasts adjacent to the East Greenland ice stream; the book is a book of photographs; the author makes no assertions of scientific discoveries; the author describes his work as the taking of photographs mainly for the scientific benefit of geologists. Michaels must also show intent: that is, the intent of the author Ernst Hofer to demonstrate, speak of or mention in even the least way the existence in 1957 of the island now known as Warming Island. In my submission: if Patrick Michaels cannot prove such intention on the part of Hofer then the map - which bears no mark of authorship or of authenticity on its face - cannot be described legally and scientifically as 'Hofer's map'. Rather, in my submission, it is an inaccurate sketch map of no scientific value which happened to suit the purposes of a self-described advocate.
  9. Between St. Roch and a cold place
    I recall years ago hearing this argument being used by a local talk-radio host as a claim against global warming. Hard to say if said host has been convinced by the evidence. Probably not.
  10. Michaels Mischief #3: Warming Island
    #38: pauls: Where in the world are glaciers advancing along with cooler temperatures? You make valid points abut point data versus regional trends, especially where data is sparse (Michaels should take notes); however there are not a great deal of locations where non-surging glaciers are advancing due to cooler temperatures. In JMurphy's link, very few glaciers show even a positive mass balance, which is a prerequisite to an advance - the positive mass balance must also be sustained over a number of years (length dependent upon the glacier) to move the terminus forwards. Additionally, those very few showing positive mass balance and advancing may be doing so on account of increased precipitation, not from lower temperatures. Furthermore, how many of those non-surging glaciers showing positive mass balance, advancing, and under a recorded cooler climate - are in a position more advanced now than they were in the 1950s? I suspect not many, but see if you can find any! But all this just distracts from the key point here that Michaels was extremely unskeptical about a sketch map, and appears to be intent upon sowing seeds of doubt, rather than following evidence. Debunking these seeds of doubt is very important, when they are as clearly incorrect as in this case.
  11. OA not OK part 20: SUMMARY 2/2
    Bernard, sorry you were confused. In post 4 we stated that "You may recall from school that a pH of 7 is neutral" and went on to explain about the dissociation of water and then clarified that "So, we define a neutral pH has the same concentration of H3O+ as pure water" (and that 'has' should have been 'as having'). We had hoped that it was obvious that this meant "...as pure water at the same conditions of temperature etc" but we can see how people might not have appreciated this. Nevertheless we felt it was as concise a definition as we could give without (as we had said we would not do) mentioning activity or delving into the intricacies of the several pH scales used for seawater.
  12. Increasing CO2 has little to no effect
    Alleycat, I think you'll dig this Alley cat.
  13. 2011 Sea Ice Minimum
    NASA weighs in on the 2011 melt season. The near-record ice-melt followed higher-than-average summer temperatures, but without the unusual weather conditions that contributed to the extreme melt of 2007. "Atmospheric and oceanic conditions were not as conducive to ice loss this year, but the melt still neared 2007 levels," said NSIDC scientist Walt Meier. Two good video segments.
  14. Michaels Mischief #3: Warming Island
    Albatross - See above. SkS has been doing just that, some examples: Certainly, I guess my concern is that SkS doesn't get drawn into meaningless debates about microclimates. JMurphy - My point is that we know there are microclimates and small regions which don't follow the wider regional and global trends. With this in mind debating the historical evolution of a microclimate (Warming Island) about which we know nothing earlier than the 1970s and very little after that is speculative at best. Observational data in the area is sparse so much better to remain focused on wider regional trends, at a level where we can make genuinely meaningful statements. As Albatross shows, SkS has a wealth of information on this.
  15. Between St. Roch and a cold place
    My first thought when I heard that vessels have navigated the passage decades ago was, "Did they sail in an ice-breaker?". As your article makes clear, if St Roch is not an ice-breaker then she is something equivalent. One point, which may sound like a quibble but is important to ex-naval types like me is could you please refer to St Roch as a ship, not a boat.
    Moderator Response: [JMurphy] Oops, sorry about that ! Looking into it, the basic definition seems to be that a ship can carry a boat but a boat can't carry a ship. I think I understand...
  16. Increasing CO2 has little to no effect
    #81, 82: Take yourself to the Most Used Climate Myths, you'll see such gems as Water vapour is the most powerful greenhouse gas, and Does breathing add CO2 to the atmosphere. You can search for more as well. I'd also recommend Richard Alley's AGU talk about why CO2 is the biggest control knob on climate despite the small overall percentage in the air. One of the best bits of science communication you'll see, and a better use of an hour of your time than browsing on most climate blogs!
  17. Increasing CO2 has little to no effect
    Alleycat... You getting a few things wrong here. First, water vapor responds to heat. More heat, more water vapor. This is very basic. The only way you get more water vapor is to turn up the heat somehow. Second, the sun varies only a very tiny amount. Of the ~1370Watts/m2 it only fluctuates about 0.5W/m2 over the course of an 11 year cycle. The sun is very stable, it just doesn't change much. We know with a high degree of accuracy how much the added CO2 has changed over the past century and we know the radiative forcing change for it (and the other man-made greenhouse gases) is about 2.4W/m2. That is a big change that turns up the thermostat and causes more water vapor to be held in the atmosphere. Human's exhaling doesn't actually add to the carbon in the atmosphere because, well, where did that carbon come from? It was already part of the natural carbon cycle. The problem comes from burning ancient carbons in the form of fossil fuels.
  18. Increasing CO2 has little to no effect
    Alleycat, you would do well to look at (and comment further, if you wish) the following threads : CO2 is a trace gas Water vapour It's the Sun Human exhalation of CO2
  19. Increasing CO2 has little to no effect
    Still, compared to water vapor, CO2 is such a miniscule percentage of the atmosphere. Water vapor and the sun itself seem to play a much greater role in the natural cycle of heating and cooling the planet. Take the sun out of the equation and no amount of man made warming would keep the planet from turning into a frozen world. You can't regulate or outlaw water vapor any more than you can CO2, they are the essential building blocks of life. Has anyone considered that the sheer numbers of humans exhaling has increased several fold over the past 100 years? Where are we now 6 billion? It was barely 2 billion when I was a kid. Could that account for increased CO2?
  20. Michaels Mischief #3: Warming Island
    pauls wrote : "The thing is that there are currently places where glaciers are advancing, places that have been cooling for the past few decades." I'm sure there are (although it would be interesting to hear from you about those cooling places - what further information do you have ?), and anyone can check to see just how many comparative glaciers are retreating/advancing at The World Glacier Monitoring Service - how many are advancing, would you think ? But, what are you trying to say with that sentence ?
  21. Michaels Mischief #3: Warming Island
    Hi Pauls @35, Oh dear, we do seem to be talking past each other and talking in circles. I'll try and communicate more clearly. "What logicman and myself have said is that you can't necessarily assume that the trends...in one location are representative of another single location even if they are nearby" Actually, I think that we are in broad agreement on this. But the degree of agreement probably depends how accurately one wishes to quantify the trend at one location using the trend data from a nearby location. But this is all rather moot and we are getting away from the fact that Michaels was not speaking about trends (or anomalies) at all, he was speaking about absolute annual temperatures as shown in his chart. "I really don't think the relative condition of a single tiny island will have much of an impact on political action to tackle global climate change." Pardon my cynicism, but I have unfortunately witnessed too many times how such chicanery by Michaels et al. has been amplified and propagated far and wide using the internet. Such demonstrably false assertions such as those made by Michaels cannot go unchallenged. "You're on a much better grounding talking about the wider regional changes across Greenland and the rest of the Arctic." See above. SkS has been doing just that, some examples: # Arctic Ice Part 2: A Review of Factors Contributing to the Recent Decline in Arctic Ice # Arctic Ice Volume is diminishing even more rapidly than Area # Arctic Sea Ice (Part 1): Is the Arctic Sea Ice recovering? A reality check # Arctic sea ice low – what does it really mean? # Arctic sea ice melt - natural or man-made? # Arctic sea ice... take 2 # Arctic Sea Ice: Why Do Skeptics Think in Only Two Dimensions? # Arctic Warming and Hadley # Articgate: perpetuating the myth that Arctic sea ice has recovered # DMI data on Arctic temperatures: Hide the Increase? # Greenland ice mass loss after the 2010 summer # Greenland Ice Sheet outlet glaciers ice loss: an overview # Greenland's ice mass loss has spread to the northwest # Gripping video of Arctic sea ice melting away before your eyes # Monckton Myth #12: Arctic Temperature Changes # Not so Permanent Permafrost # The Arctic is cooling? DMI and GISS Arctic Data
  22. Michaels Mischief #3: Warming Island
    Albatross - That is not what logicman said. He said: "Even though only 75km apart, the Daneborg and Warming Island microclimates are not, I suggest, comparable." And "Most definitely a single station's temperature series is not enough to prove that a location 800km distant exhibited exactly the same trends year on year." Nothing about anomalies. If you're talking about trends it doesn't matter whether your data are expressed in anomalies or absolute temperatures. There wouldn't be any difference in the trends. Actually his second quote basically says the same thing as I did in post 24. I do agree that the anomalies at nearby stations can probably be used to infer the anomalies or rate of warming at Warming Island, but unless one knows the offset, one cannot infer the absolute temperature, and that is what the ice responds to. We're getting a bit off track from the original point here and I would suggest you're now disagreeing with the second of your quotes from logicman. What logicman and myself have said is that you can't necessarily assume that the trends (I'll use that word because there has been some confusion over my use of 'anomalies') in one location are representative of another single location even if they are nearby. Do we really want to delay taking action on AGW because of disinformation from someone like Michaels? And that is the very inconvenient fact that Pat Michaels and Watts desperately want to distract us from. I really don't think the relative condition of a single tiny island will have much of an impact on political action to tackle global climate change. The thing is that there are currently places where glaciers are advancing, places that have been cooling for the past few decades. I think refocusing the debate to be about remote microclimates like Warming Island is the distraction that they're after. You're on a much better grounding talking about the wider regional changes across Greenland and the rest of the Arctic.
  23. Increasing CO2 has little to no effect
    CO2 is a heavy gas that tends to stay close to the ground. (otherwise plants couldn't consume it) Heat always rises, it does not fall, even when radiating in all directions, the hotter the air the faster it rises. So explain to me how CO2 is keeping any heat from simply slipping past it and rising into space? Additionally, on a cloudy day, temperatures go down, not up. Heat rising with water vapor in it tends to create more clouds and thunderstorms, which cool things even more. I can see how (at night) cloud cover would keep some heat from escaping the atmosphere, but once you're more than a few feet off the ground (even in the heat of summer) the air temperature drops dramatically. I have personally observed this as a glider pilot. Even 3000' off the ground you can see ice crystals form on your canopy with the sun shining and ground temp at 90 degrees. So someone explain it to me (taking real world observations into account).
    Moderator Response: CO2 is well mixed in the atmosphere, as has been repeatedly measured with ground stations at various altitudes, aircraft, and spacecraft. Not an assumption, but a repeated observation. That's different than what happens in a small enclosed system such as a jar. Clouds keep the surface warm at night because they prevent some infrared radiation from escaping to space. During the day they do the same thing but also prevent some of the Sun's radiation from reaching the surface, and the energy prevented from coming in can exceed the energy prevented from getting out to space. Heat does not rise. Hot air does. It cools as it rises because its pressure drops because its surroundings are at lower pressure.
  24. The 2nd law of thermodynamics and the greenhouse effect
    Re #298 Moderator Response: [Dikran Marsupial] "To avoid any further obfuscation, I will re-word the question. Do you agree that body A will radiate photons in random directions at random intervals, with total power proportional to the fourth power of the temperature of body A (i.e. according to the Stefan-Boltzmann law), and that this remains true regardless of the temperature of body B?" Yes.
    Moderator Response: [Dikran Marsupial] Good. Do you agree that the photons radiated from body A are carrying away some of the thermal energy from body A with them?
  25. Climate Change Could be Expensive for Canada
    Composer, Albatross (#5) mentioned that an earlier report concluded that the pros are probably going to outweigh the cons. This recent report, while acknowledging that there are pros, only mentions them briefly, completely excludes them from their calculations. I cannot say if the pros will outweigh the cons, but to completely omit them yields a false impression.
    Moderator Response: [John Hartz} You missed the point of my prior moderator comment. By design, the analyses contained in the report were focused on the costs of climate change to Canadians. It was not intended to be a cost-benefit analysis. The report is what it is.
  26. Climate Change Could be Expensive for Canada
    Jonathon: It was your reaction to the report, rather than the report itself, which I found to be of interest in this comment thread. I have no problem with a report produced for Canadian policy-makers which focuses on Canada. I would have a problem if the policy-makers only review the Canadian situation. You seem to be concerned that Canadians are getting a false impression about AGW from the NRT report. Based on your comments thus far, am I correct in guessing that you conclude that the benefits from AGW for Canada would outweigh the costs for Canada? A simple yes or no response will do. If yes, my question is: Even if it is the case that Canadians would stand to benefit materially from AGW for a number of decades, whether Canadians (or any subset of Canadians) should ignore the overwhelmingly negative implications of AGW elsewhere when making policy.
  27. 2011 Sea Ice Minimum
    Relating to my Gompertz graphic above, and other discussion about S curves, I just posted several updated versions including one based on the complete 1972-2011 Uni Bremen extent time series, and another for PIOMAS volume, More explanation/discussion at Neven's place: http://neven1.typepad.com/blog/2011/10/september-2011-sea-ice-extent-looking-ahead.html http://neven1.typepad.com/blog/2011/10/september-2011-sea-ice-volume-looking-back-and-ahead.html
  28. Michaels Mischief #3: Warming Island
    Pauls, I'm sorry but we are going to have to agree to disagree. "I don't disagree with this but we're not comparing the melt rate at two different locations." I gave an example, I am well aware that we are discussing what might have transpired at a given location (i.e., Warming Island). You say "logicman's argument was that the 'nearby' station shouldn't be used to infer temperature anomalies at Warming Island because the climate conditions are different." That is not what logicman said. He said: "Even though only 75km apart, the Daneborg and Warming Island microclimates are not, I suggest, comparable." And "Most definitely a single station's temperature series is not enough to prove that a location 800km distant exhibited exactly the same trends year on year." Nothing about anomalies. Also, the temperature chart that Michaels showed was annual temperatures, not annual anomalies, so those data presented by Michaels really do not say much about the temperatures at Warming Island. I do agree that the anomalies at nearby stations can probably be used to infer the anomalies or rate of warming at Warming Island, but unless one knows the offset, one cannot infer the absolute temperature, and that is what the ice responds to. But us not forget what Michaels said: "As it turns out, maps show that Warming Island, indeed, was very much an island a mere 50 years ago, when Greenland, in fact, was warmer than it has been for the last 10 years." None of the data presented here support such a confident assertion by Michaels. The period of warmer temperatures was actually much earlier than the 50s (when temperatures were actually declining) and as shown by Box et al., the claim that the temperatures in Greenland 50 years ago were warmer than recent temperatures is demonstrably false. Some might use stronger language than I to describe the claims made by Michaels....
  29. keithpickering at 06:46 AM on 5 October 2011
    Between St. Roch and a cold place
    FYI, the St. Roch still exists, and is on permanent display in the Vancouver Maritime Museum.
    Moderator Response: Yes, and the first link in the post is to that museum; but, unfortunately, the actual pages for the St. Roch are currently being redeveloped and are not accessible.
  30. Climate Change Could be Expensive for Canada
    John, I have no problem with the report focusing on Canada. Others seem to be objecting that the costs and benefits are not seen in a global light. But as you say, the focus was designed to be solely about Canada.
  31. Michaels Mischief #3: Warming Island
    Pauls, "Certainly Michael's argument for why it was has been taken apart here, but that doesn't necessarily mean he's incorrect." Actually, the preponderance of evidence strongly suggests that Michaels and his apologists are very likely incorrect. 1) The temperature data from nearby stations suggest that temperatures peaked in the thirties, showing a decline/drop until 1957 (see Michaels' own data, and the data shown by Dana and Robert). Those same data show that current temperatures are in fact warmer than they were back then. 2) Similarly, positive degree data (Box et al.) shown by Tom Curtis show two important things: i) The number of melt days in the 30s and 40s were, on average, fewer then those observed of late; ii) The number of melt days declined from the maximum in the late 30s (which was lower than maxima of late) until around about 1970, after which they increased again, with a sharp increase after 1990. 3) Photos of nearby glaciers (again shown by Curtis above) show that the glaciers in the 30s were in much better shape back then than they are of late. 4) The transient warming observed earlier in the 20th century certainly did not result in a ~180m increase in sea level. The fact that Michaels uncritically accepted the map as proof that Warming Isl. was present in 1957, speaks to his confirmation bias and once-sided skepticism. Do we really want to delay taking action on AGW because of disinformation from someone like Michaels? Box et al. (2009) talk of a warming period between 1919 and 1932 over Greenland, long before the 1957 map. More importantly though is what the past tells us about the future, and that is that the ice sheet is sensitive to warming, that warm spell in 1919-1932 was transient, indications are that we can expect Greenland to continue warming for many decades to come (barring of course volcanic activity or prolonged negative phase of the NAO): "Climate warming has pushed the Greenland ice sheet beyond its threshold of viability in recent years (Rignot et al. 2008). The ice sheet seems poised not to grow without substantial regional and global climate cooling. It therefore seems much more likely that not that Greenland is and will be for the foreseeable future be a deglaciating Pleistocene Ice Age relic." And that is the very inconvenient fact that Pat Michaels and Watts desperately want to distract us from. PS: Box et al. (2009) do note that there is evidence of glaciers and ice sheets retreating in the 20s and 40s in response to the warming (contrary to what Michaels and Watts would have you believe that is evidence that climate sensitivity is high not low), but not the fifties. However, as shown by Tom Curtis above, we know from the analysis of several glaciers in Greenland is that the glaciers back then were much larger/extensive than they are now.
  32. The 2nd law of thermodynamics and the greenhouse effect
    While I agree with Philippe, I do like the re-wording of the question.
  33. Philippe Chantreau at 06:08 AM on 5 October 2011
    The 2nd law of thermodynamics and the greenhouse effect
    Dikran, you are wasting your time.
    Moderator Response: [Dikran Marsupial] Yes, I know I probably am, but I am trying to give damorbel a chance to demonstrate that he is more than just a troll and willing to engage in a proper discussion. Currently he is wasting the opportunity with extreme pedantry.
  34. Michaels Mischief #3: Warming Island
    Albatross - Absolute temperature does matter for melting ice is the, how many "melting" days there are. Two nearby locations can warm at a similar rate or have anomalies of similar magnitude, but if one is starting from a lower base temperature (beause of microclimate, for example) it will take that station longer to reach a critical threshold such as the melting point. I don't disagree with this but we're not comparing the melt rate at two different locations. We're comparing melt at a single location at two different times: the 1950s and the 2000s. It has then been pointed out that a 'nearby' weather station shows temperature anomalies that were about the same in the 1940s & 1950s as in the 2000s. So logicman's argument is still valid. logicman's argument was that the 'nearby' station shouldn't be used to infer temperature anomalies at Warming Island because the climate conditions are different. Barry was asking how this could be since it is within the 1200km distance used by GISS to infer spatial correlation. I've given my answer in post 24. I don't think citing the difference between anomalies and absolute temperatures supports logicman's argument and I don't think it is relevant in this case.
  35. Philippe Chantreau at 06:03 AM on 5 October 2011
    Between St. Roch and a cold place
    Nice work JM. Another "skeptic" argument demonstrating how skepticism is all but lacking.
    Moderator Response: [JMurphy] Thanks. The 'argument' has never sounded convincing but some people just seem to accept it - not true sceptics, as you suggest.
  36. The 2nd law of thermodynamics and the greenhouse effect
    Re #296 Moderator Response: [Dikran Marsupial] You wrote "This is obfuscation. I explicitly said that the temperature of the bodies was a point that will be discussed later" Temperature will be discussed later? Then what do you mean when you write:- 1/(in #290):- "Do you agree that any body at a temperature above zero degrees Kelvin will radiate" 2/(in #291):- "power per unit surface area proportional to fourth power of temperature" 3/(in #294):- "is proportional to the fourth power of its temperature, according to the Stefan Boltzmann law?" 4/(in #295):- "Unlike the first black body, the second is at zero Kelvin" 5/(in #296):- " so now consider the case where B is above zero Kelvin, but cooler than A" 6/(in #297):- "O.K., say B is at the same temperature as A." And so forth?
    Moderator Response: [Dikran Marsupial] Your pedantry does you no favours. O.K. I shall reword it for you, we will discuss the change in temperature of the two bodies later. Now please give a direct answer to the question I posed.

    If you want to demonstrate that you are merely a troll, this sort of pedantry, whilst avoiding answering the question is exactly the right way to go about it. I am trying to do you a favour here by encouraging a more productive discussion by going through it step by step to see if you are willing to engage with the discussion. You a wasting an opportunity here, but it is your loss.
  37. Review of Rough Winds: Extreme Weather and Climate Change by James Powell
    175, Eric,
    ...Masters' energy concept and Ostro's "confluence" of natural factors with AGW. Those are too loose and too vague...
    I agree. The connection between energy and weather is logical, but lots of things seem logical at first thought but turn out to be far more complex and nuanced.
  38. Michaels Mischief #3: Warming Island
    Pauls @29 and Barry, "What is being discussed is a change in conditions over time at Warming Island, not the absolute temperature, so it is anomalies that matter in this case too" I was trying to clarify the confusion about the auto-correlaton length for the anomalies. Absolute temperature does matter for melting ice is the, how many "melting" days there are. Two nearby locations can warm at a similar rate or have anomalies of similar magnitude, but if one is starting from a lower base temperature (beause of microclimate, for example) it will take that station longer to reach a critical threshold such as the melting point. So logicman's argument is still valid. But that is air temperature, we know also that ocean temperatures are warming and some of the recent melt was probably also attributable to the warmer ocean temperatures in that region.
  39. Climate Change Could be Expensive for Canada
    Composer99 Except for the Arctic ice cap, none of those places are within provinces or territories of Canada. Therefore, why should they have been included in a report about Canada? I do not believe that anyone here was encouraging climate change. Even those posters who suspect that Canada will benefit financial are not espousing climate change. The report was carefully cherry-picked to only include those items which produced the desired outcome. If you think that heating bills will not be affected, you may want to think again. Focusing on only the cooling side of energy bills is akin to presenting data that the Antarctic peninsula has lost ice, therefore all of Antarctic is melting, or that Tuvalu has gained area, therefore all pacific islands are growing. Do you see the problem with focusing on a relatively small fraction of the whole?
    Moderator Response: [John Hartz] The analyses summarized in this report were by design focused on the potential costs of climate change to Canada. If that gives you heartburn, so be it.
  40. Eric (skeptic) at 05:12 AM on 5 October 2011
    Review of Rough Winds: Extreme Weather and Climate Change by James Powell
    Sphaerica, I generally agree. Some phenomena like intense rainfall have a much more linear relationship to AGW than others like tornadoes or (to some extent) hurricane formation and intensity. Maybe a good compromise for a book like this is to briefly describe the connections, the direct ones like increased evaporation causing floods and exacerbating droughts. Then the indirect ones like instability, lapse rate, horizontal temperature gradients, etc which will vary nonlinearly with AGW but are also much more prone to natural variations. The author should either explain it somehow or leave it out (e.g. strong tornadoes) but not just repeat Masters' energy concept and Ostro's "confluence" of natural factors with AGW. Those are too loose and too vague IMO and do not justify adding strong tornadoes into the book.
  41. Michaels Mischief #3: Warming Island
    Tom Curtis at 23:54 PM on 4 October, 2011 Pauls @24, I believe it is a mistake to assume ice behavious is a simple function of annual temperatures. In fairness, the statistical relationship between temperature and sea ice minimums for a year is very strong. http://clearscience.wordpress.com/2010/11/19/predicting-past-sea-ice-extents/ The issues I have with Middleton are the use of GISP2 and greenland anomalies to characterize sea ice extent. I think I demonstrated somewhere recently that the relationship between ice volume and arctic air temperature is R2 = 0.77 (I was going to do a post on it one time). That's a pretty strong result. Maybe I should respond? haha
  42. The 2nd law of thermodynamics and the greenhouse effect
    Re #296 Moderator Response: [Dikran Marsupial] you wrote:- 1/ "say B is at the same temperature as A. (i) Would you agree that the emission of photons from A is not affected by this ". Yes, as long as the temperature of A is not changed by this. 2/ "or does it [A] continue to emit photons with total power according to the Stefan-Boltzmann law " I think this is the same question, no 'or' about it; if A is still above 0K then A continues to emit photons, some of which will continue to be intercepted by B. 3/ "ii) Some photons from A will still hit and be absorbed by B, thus transferring some energy from A to B." No, there would be no change in the energy of either A or B because they are at the same temperature.
    Moderator Response: [Dikran Marsupial] This is obfuscation. I explicitly said that the temperature of the bodies was a point that will be discussed later. I asked whether you agree that the emission of photons from body A remained as before, with photons emitted at random intervals and in random directions with total power given by the Stefan Boltzman law (which already describes the dependence on temperature).

    To avoid any further obfuscation, I will re-word the question. Do you agree that body A will radiate photons in random directions at random intervals, with total power proportional to the fourth power of the temperature of body A (i.e. according to the Stefan-Boltzmann law), and that this remains true regardless of the temperature of body B?
  43. Climate Change Could be Expensive for Canada
    Jonathon: What part of 'global' in AGW are you missing? Are Bangladesh, the Netherlands, the southern US, tropical countries world-wide, small Pacific islands, the Amazon basin, and the Arctic ice cap so insignificant that Ontarians should encourage global climate change to save some money on their heating bills? Also, given the wide range and scope of impacts (e.g. the destruction of pine forests as noted upthread, or the ongoing glacier melt and Arctic impacts), focusing on heating bills strikes me as a carefully-chosen cherry-pick.
  44. Crux of a Core, Part 3... Dr. Ole Humlum
    ...Regarding previous comment - But of course, you knew that, since we're commenting on the Crux of a Core thread in the first place. I have to be more careful about context when following recent comments - sigh.
  45. Crux of a Core, Part 3... Dr. Ole Humlum
    citizenschallenge - That site, and Ole Humlum in general, have been discussed here. Search on "Humlum", which will take you to here, here, or here. Ole Humlum has repeatedly focused on the GISP2 core (a local record), leaving out or incorrectly matching the recent instrumental record, cherry-picking short time frames, and in general making a hash of the data to support his "it's not happening" points. Rob Honeycutt's Crux of a Core series addresses this topic quite thoroughly.
  46. citizenschallenge at 02:55 AM on 5 October 2011
    Crux of a Core, Part 3... Dr. Ole Humlum
    Does anyone know of others who have been examining and debunking Climate4you? I've been doing various web searches but am coming up disappointingly empty. Seeking further info
  47. Michaels Mischief #3: Warming Island
    Albatross - What is being discussed is a change in conditions over time at Warming Island, not the absolute temperature, so it is anomalies that matter in this case too. 'Why shouldn't the anomaly trends at 800km-away Angmagssalik be representative of those at Warming Island given Hansen's oft-referenced 1200km radius?' is the question Barry is asking.
  48. Debunking Climate Myths from Politicians
    A ray of hope from Republican former Congressman Bob Inglis. Perhaps more conservatives will have the courage to speak about the conflict of Conservatism vs Science. "When it comes to energy and climate, these are not normal times. We’re following sentiment, not science, we’re turning a blind eye to accountability, and we’re failing to use the power of markets."
  49. Michaels Mischief #3: Warming Island
    Barry @22, Please note KR's post @27. There lies the answer-- Hansen's group is looking at the correlation of anomalies. From the NASA GISTMEP site: "The reason to work with anomalies, rather than absolute temperature is that absolute temperature varies markedly in short distances, while monthly or annual temperature anomalies are representative of a much larger region. Indeed, we have shown (Hansen and Lebedeff, 1987) that temperature anomalies are strongly correlated out to distances of the order of 1000 km. "
  50. Review of Rough Winds: Extreme Weather and Climate Change by James Powell
    Eric, I think the tornado issue is a strawman anyway. No one ever said that every weather event had to increase in frequency and intensity, or that such increases must be detectable in the same time frames. It is quite possible that some events (floods, droughts) will increase in frequency and intensity, others (hurricanes) only in either frequency or intensity, and some (tornadoes) may even diminish in one or both of intensity and frequency. Or they may diminish at first, and then undergo an unexpected increase at a later date, when a new tipping point is reached. Tornadoes in particular seem to rely on extreme temperature gradients rather than available energy. So an increase in temperatures with a reduction in the gradients may decrease the frequency and usual intensity of storms. But the higher energies and temperatures available in the system may also make short outbursts of more or more intense storms more possible and frequent than before. So you'd see an overall reduction in storms and intensity, and yet begin to have more experience with the nasty scenario of a weekend of a flurry of nasty, evil storms. So that's something you'd wind up measuring one way (overall statistical decrease) when reality to the people withstanding the onslaught is very different.

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