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Comments 77001 to 77050:

  1. Arctic icemelt is a natural cycle
    CBD: "... it does not." An understatement. Kay et al 2011 say just the opposite of Ryan's claim: On all timescales examined (2–50+ years), the most extreme negative observed late 20th century trends cannot be explained by modeled natural variability alone. ... In a warming world, CCSM4 shows that multi-decadal negative trends increase in frequency and magnitude, and that trend variability on 2–10 year timescales increases. --emphasis added
  2. Arctic icemelt is a natural cycle
    Ryan#46: "any current trend is also natural," Prove it. Historic records, consistent with modern measurements, say different. Looks like the 'natural cycle' is flat and the recent melt is anything but natural.
  3. A new SkS resource: climate skeptics and their myths
    17, RyanStarr, Oh, and "discussing" Postma isn't being skeptical, it's being just on this side of rational compared to the (-Snip-). Holding up "discussion" of Postma as a demonstration of true skepticism is a complete joke.
    Response:

    [DB] Tsk.  Too far.

  4. A new SkS resource: climate skeptics and their myths
    Ryan, actually we DO exercise scientific skepticism here. However, I am starting to notice a pattern where you say completely false things and then seem to avoid looking at or responding to any evidence to the contrary cited. If you think that is skepticism then you are doing it wrong.
  5. A new SkS resource: climate skeptics and their myths
    17, RyanStarr, If you are skeptical of Mann, then you have a lot of reading to do, beginning with all of his actual science publications. You should also have a very firm grasp of what PCA is, how he used (or misused) it, as well as all of the myriad, gross weaknesses in McIntyre's and Wegman's and other's attacks. You should also recognize how silly the attacks on him are. They are all focused on one ten year old graph that has been validated and reinforced repeatedly over the intervening years, while all assaults on it have been utter failures. Science has moved on, and anyone who says "Mann! Mann! Hockey-stick" is lost in denial. If you're so skeptical, actually look and educate yourself. And I know you haven't based on what you said about Mann. That particular case is absolutely cut and dry, and for you to say what you have says you don't know and don't understand, and since all of the information is readily available, that means that you just haven't bothered to look, or to do so with a properly skeptical eye. Please get a clue.
  6. A new SkS resource: climate skeptics and their myths
    CBD are you saying that at "Skeptical Science" we don't exercise scientific skepticism? Or exercise it selectively. I'm skeptical of Mann, Gore, and I'm skeptical of that Postma guy. At the real skeptic sites they've already discussed him, questioned his work, they do that, even though he was skeptical of AGW.
    Response:

    [DB] "At the real skeptic sites they've already discussed him"

    At real skeptical sites, like Skeptical Science, all is viewed through the lense of the science itself, not through ideology nor climastrology (no mythical "cycles").

  7. ClimateWatcher at 01:13 AM on 19 August 2011
    A new SkS resource: climate skeptics and their myths
    Roger Pielke?
  8. ClimateWatcher at 01:12 AM on 19 August 2011
    A new SkS resource: climate skeptics and their myths
    Where's Pat Michaels?
    Response:

    [dana1981] On the aforementioned 'unpublished' list, though I got his entry ready for publication last night.  We must have neglected to publish it.  We'll add him to the sks.to/skeptics page shortly.

  9. It's waste heat
    mullumhillbilly - The disproportionate amount of energy retained by GHG emissions versus combustion is because the GHG's retain solar energy (fusion), not just release a bit of chemical energy (combustion). By comparison to any amount of coal burnt, the sun is an essentially limitless energy input. A gift that just keeps on giving, unfortunately... I will note that Gedankenexperiments regarding greenhouses, glass plates, etc., have led a number of commenters astray - glass greenhouse analogies really don't capture the details of radiative physics and energy flows.
  10. Arctic icemelt is a natural cycle
    RyanStarr, most of what you claim this study says or suggests... it does not. Perhaps you should read it before commenting further on 'what it means'.
  11. rustneversleeps at 01:05 AM on 19 August 2011
    A new SkS resource: climate skeptics and their myths
    My! What a diverse group they are! :p
  12. Arctic icemelt is a natural cycle
    @CBD, thanks or reply, I think we have to keep in mind how short the current record is, and of course there is a first for everything. With short records we can expect to see lots of 'firsts'!
  13. A new SkS resource: climate skeptics and their myths
    RyanStarr, Michael Mann is not a climate skeptic and the claims that the hockey stick was inaccurate and proxy inputs were upside down are themselves long-debunked myths.
  14. Arctic icemelt is a natural cycle
    @DB, not sure what you mean, the general message from the AGW supporting side of the argument has been that ice loss is accelerating and will continue to as CO2 levels rise. This study suggests otherwise, that a high degree of natural variability exists in the decadal time frame. They say 50-60 years is required to pass before warming effects become apparent. It would also suggest that any current trend is also natural, unless you want to entertain the notion of 'spurts' of AGW ice loss. This very much contradicts the view popularly expressed on this site, this thread actually. The news isn't so old, it's still August, and hasn't been discussed _here_ at all.
    Response:

    [DB] For the many reasons stated earlier, the study is essentially a thought experiment not supported by actual observations and metrics.  You were pointed out why it's not applicable to what we observe and measure by myself in my earlier response to you and by CBD in his repy to you above.

    "The news isn't so old, it's still August,"

    Compared to the rate of demise of the Arctic Sea Ice, as ably denoted by muoncounter below, the study is indeed old news.  Obsolete, even.

    "and hasn't been discussed _here_ at all."

    Just because we allow occasional reinvention of the wheel does not also mean we will suffer through continual reinvention of the flat tire.

  15. A new SkS resource: climate skeptics and their myths
    One of the obvious next steps (which I'm guessing you already have in mind) would be an extension to the 'contradictions' section, to show which skeptics disagree with each other on which issues. e.g. I think Spencer and Lindzen both agree that the CO2 rise is anthropogenic and the greenhouse effect is real, Salby disagrees with both of these. What I would expect to emerge would be a highly fractured and inconsistent body of knowledge. This can then be contrasted with the level of consistency of the consensus position (while still representing the areas of uncertainty). A good graphical representation of this would help: perhaps throw in an equal number of consensus scientists, and for each pairwise comparison tot up the number of points on which they agree and disagree. Then refine everyone represented by a point in a 2d plane with number of points of disagreement as a distance metric. The graphviz tool 'Dot' can do this for you. It's a lot of work though. Not sure what would emerge. Are there any skeptics who argue for a high climate sensitivity? Or at least any who don't argue for low sensitivity? So on some issues, the skeptic community might be more clustered.
    Response:

    [dana1981] You are correct, we have also started a database of "skeptics" debunking "skeptic" myths.

  16. A new SkS resource: climate skeptics and their myths
    Where's Michael Mann? He of the hockey stick generator and upside down proxy inputs.
    Response:

    [dana1981] Mann does not purvey climate myths and therefore does not belong on the list.  You would be well served to read some of our entries on the hockey stick.

  17. A new SkS resource: climate skeptics and their myths
    If I might... For me the pictures, let alone other info people have suggested, risk moving this more and more into the "witch hunt" domain. I'm happy enough for a page with names to aid navigation, I'm even quite fond of the "Spencer slip ups" type badges - but please, please be careful that SkS doesn't slip from "these are people who [also] do bad science" to "these are bad people"...
  18. A new SkS resource: climate skeptics and their myths
    Also McIntyre, Watts, Wegman? Two have failed attempts at fudging the Hockey Stick (and some egregious secret ranking of their data too), one a plagiarised Congress report, and one has a lame attempt at finding errors in the surface station record, quite apart from the promotion of any old rubbish that happens to disagree with the accepted science. Those three have many hits between them.
    Response:

    [dana1981] Like Armstrong (see comment above), Watts and McIntyre are on our 'unpublished' list.  Hopefully at some point we'll have the time to complete their entries and add them to the public list.  Ditto for adding Wegman eventually.

  19. A new SkS resource: climate skeptics and their myths
    You could also include Vincent Courtillot. His presentation makes the suggestion that the sun might be able to explain observed changes in the global mean temperature anomaly. There's more interest in analyzing the work of actual scientists than there is in debunking the likes of Abbott who debunks himself!
  20. A new SkS resource: climate skeptics and their myths
    This is a great list. I can't wait to see where you go with this and I think it is a great idea. You should add J. Scott Armstrong in there. The marketer who thinks he can discredit global warming science by comparing it to other unrelated scientific studies.
    Response:

    [dana1981] Armstrong is on our 'unpublished' list, meaning we have him on our radar and some information added, but not enough to make his entry worth making public yet.  We've covered Armstrong previously here and here.

  21. A new SkS resource: climate skeptics and their myths
    "Monckton unfortunately packs a punch above his weight and I can only apologise on behalf my fellow Brits," Monkton is a ready made caricature, he is also a huge embarrassment to many skeptics that there is a tendency in some places to complain that using him is a ruse to make all skeptics look foolish. I think of him as a Terry Prachett character come to life. There is a certain hierarchy with the likes of Lindzen at the top with Ridley and Salby not too far behind while the bottom is most crowded.
  22. A new SkS resource: climate skeptics and their myths
    Mind you, Monckton unfortunately packs a punch above his weight and I can only apologise on behalf my fellow Brits, that the US and Australia have to suffer his presence on what appears to be a regular basis.
  23. A new SkS resource: climate skeptics and their myths
    Is that the best we British can do?? Actually the good news is that there is a big boost in the number of students studying physics in the UK. It's become a 'cool' subject due to 'The Big Bang Theory' comedy series and the 'Brian Cox' effect. http://www.telegraph.co.uk/education/8708742/A-level-results-maths-and-science-surge-due-to-Brian-Cox-effect.html
  24. Dikran Marsupial at 22:09 PM on 18 August 2011
    A new SkS resource: climate skeptics and their myths
    Garethman: As far as I can see there is nothing here to suggest any form of ranking of skeptics in any way, it is just a way of navigating to suitable discussions of mistaken ideas that they have promulgated.
    Response: They're currently ordered alphabetically.
  25. Polar bear numbers are increasing
    Garethman: "Do I smell the scent of double standards and hypocrisy?" No, I'm afraid you're smelling something else there. Can polar bear numbers decrease due to hunting? Why yes... yes they can. Until the 1960s there were no restrictions on hunting polar bears and the population dwindled to just a few thousand bears. They were on the brink of extinction. Can polar bear losses due to hunting be reversed? Again, yes... yes they can. When hunting limits were put in place the polar bear population exploded (~500% growth) over the next 30 years. From these things we can see that allowing hunting can decrease polar bear numbers and restricting hunting can increase them. There are laws and ongoing monitoring in place to determine whether hunting is decreasing polar bear populations and to adjust quotas accordingly. Ergo, hunting does not seem to be a long term threat to polar bear survival. Now, let's look at habitat loss. If the area where the bears hunt and den gets smaller can polar bear numbers decrease? Yes... less area for polar bears equals less polar bears. Indeed, polar bear numbers are now decreasing in many areas where hunting has not increased... but sea ice has retreated. Do we have laws and monitoring in place to reverse habitat loss when it causes polar bear numbers to decrease? No. So... regulated hunting is not a threat to polar bear survival... while unregulated habitat destruction is. Gee, which issue is it hypocritical to focus on?
  26. A new SkS resource: climate skeptics and their myths
    #1: On climate science, most of these people do have the same level of achievement and understanding of climate science. They've all earned their place on this 'honours board' with ideas ranging from the fanciful to the outright false. I approve of Gore's recent straight-talking speech, and his turn of phrase could be used for all manner of wacky, self-contradictory hypotheses that this crowd have dreamed up. I don't really care if the likes of Salby has some academic baubles in his past, he should have known that the misinformation he promoted was the inconsistent garbage it clearly was. He was out of his field and out of his depth, yet his misinformation contributes to a delay in dealing with the problem. That makes him no better for climate science than Monckton, or colourless, odourless Tony Abbott! You're absolutely right about Monckton though...
  27. There is no consensus
    Rickoxo, which "scientific community"? Petroleum geologists? Yes, it would probably be accurate to say that there is a "considerable presence" of IPCC doubters within that group... though the American Association of Petroleum Geologists finally tossed their 'climate change is a sham' position in July 2007 due to protests from many members. That made them the last national scientific organization in the world to announce that humans were indeed causing global warming - though they still question how much. Climate scientists on the other hand... there is no question. The number of 'doubters' is in the single digits, both in total numbers and percentage of the field. So, sure... you can find scientists who dispute global warming science. Generally, the less it has to do with their field of research and/or the more it could impact their finances, the more likely they are to disbelieve. BTW, the fact that 'scientist doubters' exist is covered in the article above (particularly the 'Intermediate' version). The graph from the Doran study shows that less than 10% (looks like about 8%) of scientists in fields other than climatology believe that humans are NOT causing significant warming. Is 8% of the non-climatologist scientific community a "considerable presence"? Sure... but obviously tiny compared to the 77% who believe that humans ARE causing significant warming. Not to mention the 97% of actively publishing climatologists who say the same. Put another way, doubters are outnumbered 10 to 1 amongst the general scientific population and 97 to 1 amongst the experts in the field.
  28. A new SkS resource: climate skeptics and their myths
    While all these guys are dammed due to their opinions and science, it’s sad to see them all lumped together as if they all have the same level of achievement and understanding. For instance placing Salby and Monkton in the same group tends to suggest a lack of insight into the academic and achievement levels of each individual. A review of the publishing history of Salby and Monkton will clarify that. Salby may well be wrong in some issues but has an excellent history of useful work., Monkton however is a complete plonker with no redeeming features. While there are quite a few of these people, are there any sceptics who have published anything reasonable who also may also be included?
    Response: [JC] Its funny you should mention that. There is an effort to display the number of peer-reviewed papers by each skeptic in a single webpage. The work is still under progress but suffice to say the number zero features frequently.

    I also plan to break up the skeptics into separate groups (including scientists) but the resource need to be bigger. This is just a first step.
  29. Polar bear numbers are increasing
    Four bears found in the sea, presumably drowned. Worldwide attention and focus on potential risk of climate change to polar bears. Thousands killed by hunting legally or illegally killed over the last 3 years. A painful silence ensues. Do I smell the scent of double standards and hypocrisy? I’m pleased to see this posting had the honesty to point out the hunting issue. While we may not be able to conclusively show a bear died from shrinking sea ice, a bullet in the head is pretty conclusive.
    Response:

    [DB] "double standards" "hypocrisy" "honesty"

    Your ideology is showing; such talk has no place at SkS.  If you cannot construct a comment based upon the science...then don't make the comment.

  30. Arctic icemelt is a natural cycle
    RyanStarr, setting aside the fact that it IS a new study and thus there hasn't been time to analyze or test its accuracy yet; The study author also said that it should not be taken to mean that the Arctic ice is not retreating. Rather, when they incorporated what they believe to be the possible range of mechanical impacts on sea ice loss (a new form of analysis which they had to assign large uncertainty bands to) they found that the trend over the next 10 years could be either up or down... but that the trend over the next 20 or more years was sharply downward. The biggest problem I see with their argument that the upcoming ten years could see a significant upward trend is that there hasn't been a single previous upward trend of that duration in the satellite record. If you cherry pick very carefully you can find a couple of five year periods where the trend was slightly positive, but nothing close to statistical significance let alone a ten year duration. If they were right about mechanical effects producing a roughly 50% chance of significant 10 year upward trends then we should have seen one by now, or at least something close. Time will tell. However, it doesn't change the fact that we are currently at a record low ice volume, a record low ice area, and a near record low ice extent. The only reason the extent isn't a record low is that the average concentration of the ice pack is. Currently, only ~57% of the ice extent is actually covered in ice (e.g. ice area is 57% of ice extent). Basically, this means that the ice is more spread out than at any previous time in the satellite record. 2007 set the record low extent because winds pushed the ice into a small highly concentrated mass. 2011 currently has an only slightly higher extent despite the ice being the most spread out it has ever been. This is consistent with an example I've been using for a few years; Consider a 10' x 10' x 10' cube: Volume = 1000 cu ft, Area = 100 sq ft, Extent = 100 sq ft Now break it into 1000 1' x 1' x 1' cubes scattered in a 15% concentration: Volume = 1000 cu ft, Area = 1000 sq ft, Extent = 6667 sq ft The same volume of ice, but broken up and spread out it has 10 times the area and 66.67 times the extent. To get extent back down to 100 sq ft, 985 of the 1' x 1' x 1' cubes (98.5%) would have to melt. Obviously that is the extreme case and that kind of perfect breakup and spreading doesn't occur naturally, but it illustrates how it is possible for extent to remain largely unchanged as the ice breaks up and melts away. According to PIOMAS ice volume has set a new record low for the day, each and every day, from 12/20/2009 through 07/31/2011 (the last date data is available for currently). That's 589 consecutive days of new record lows. If the rate of volume decline seen over that time period continued then volume would hit zero in three years. As DB notes, Maslowski's volume projection is the only 'model' which has matched the rate of ice loss over the past five years or so. If that doesn't change in the next few years we'll be seeing only tiny remnants of ice in summers within this decade.
  31. Soil Carbon in the Australian Political Debate (Part 2 of 2)
    The Human Weathervane What I find most disappointing about Abbott's antics is knowing that he has not always been a denier. In early 2009 he was supporting former leader Malcolm Turnbull in advocating and emissions trading scheme. A self-described political "weathervane" [i], Abbott turned against pricing carbon in his pursuit of power. Perhaps this illustrates his recent remark to colleagues that faced with a choice between "policy purity and pragmatic political pragmatism, I'll take pragmatism every time" [ii]. [i] The Australian of 8 December 2009, Turnbull brands Abbot an ETS "weathervane" [ii] National Nine News of 27 May 2011, Abbott backs whips over MP email
  32. Soil Carbon in the Australian Political Debate (Part 2 of 2)
    To read comments on the relative merits of various methods of carbon sequestration (forestry, soil carbon, biochar), refer to Part 1
  33. The Ridley Riddle Part Three: Like a Northern Rock
    Mighty Drunken ....."ever have a leverage ratio of more than 10 - if you do not want a banking collapse.".... Capitalism has proved itself incapable of escaping the boom then bust cycle. That's the system. However to isolate the real villains in this particular cycle is important. Goldman Sachs is at one extreme and Northern Rock at the other. Goldman Sachs executives and related hedge fund should be in jail and perhaps will. Northern Rock were naive and thought they could always go to the market for money against their portfolio. If Northern Rock was a private bank whose shares could not be shorted they could have survived the downturn. Mortgages it may surprise you to know have an average life of less than 3 years. Northern Rock could have stopped lending shut most branches paid off the bulk of the staff and use the expired mortgage returns of capital to redeem bonds. This is essentially what the "bad bank model" is. The "bad bank" makes a profit. The only long term solution is the world socialist revolution.
  34. There is no consensus
    New reader here, more on the skeptic side but appreciative of the mostly content-centric discussions. I'm interested in a wide range of AGW related topics but don't always have the scientific background to get as far as I'd like. This thread seems as good a place as any to dive in. I was reading through this thread and an idea got brought up back a while ago about the American Physical Society starting up a published debate. In the discussion, paledriver gave some good info about the newsletter and the discussion pretty much seemed to die off. I get that the link Austerlitz posted gave an inaccurate representation of the story, but I'm still curious about the most simple piece of this issue--the quote saying, "there is a considerable presence within the scientific community of people who do not agree with the IPCC conclusion." What about this quote? Is Marque wrong? It's his opinion, but given his job and contacts, doesn't his opinion seem significant? Thanks for any thoughts - Rick
  35. Dikran Marsupial at 19:08 PM on 18 August 2011
    Understanding the CO2 lag in past climate change
    Dr. Doom (i) the logarithm has no limit, ln(x) -> infinity as x -> infinity, and hence there is no limit to climate sensitifity. (ii) the sensitivity is generally expressed in terms of a doubling of CO2 exactly because the relation is logarithmic, which means it is exactly the same for any doubling of CO2, i.e. it is the same from 100ppm to 200pmm as it is from 200ppm to 400 ppmv etc. Again you are missing the point that you mentioned the equilibrium sensitivity, there hasn't been enough time for that equilibrium to have been met since the start of the 20th century; hence you can't use the temperature difference to directly estimate climate sensitivity. It is quite obvious from your comments that your grasp of what climate sensitivity actually is is fairly weak. I suggest before posting more messages you familiarise yourself with the basics by reading the relavant posts and follow up the links provided. I would start with How sensitive is our climate, read all three versions, basic, intermediate and advanced.
  36. Understanding the CO2 lag in past climate change
    Dikran, if CO2 forcing is logarithmic, then there is a limit to its climate sensitivity. What is that limit? Since CO2 increased 37% from pre-industrial level and temp. increased 0.7C last century, the CO2 doubling sensitivity must be less than 1.9C (0.7/0.37 = 1.9) It would be 1.9C if it were linear but since you said it was logarithmic, it must be <1.9. This is smaller than IPCC predicts.
  37. Dikran Marsupial at 18:05 PM on 18 August 2011
    Linking Extreme Weather and Global Warming
    Dr. Doom The sensitivity to a doubling of CO2 is only 2-4.5C after including the effects of feedback mechanisms, such as the water vapour feedback to which you refer. The direct sensitivity to a doubling of CO2 is about 1C. This is also the equilibrium sensitivity, and is the temperature rise once the ocean temperatures have reached the new equilibrium, which takes a century or so. It isn't the instantaneous sensitivity. The Earth has warmed up by about the amount expected. However this is taking the discussion off-topic (extreme weather is the topic).
  38. Linking Extreme Weather and Global Warming
    Anne Marie, That 4% increase in water vapor in 40 yrs. can have a greater warming effect than doubling of CO2. Water vapor is the most abundant greenhouse gas, 30 times more H2O molecules than CO2 molecules in the atmosphere. In absolute molecular count, a 4% increase in H2O is greater than a 100% increase in CO2. Since the sensitivity of doubling CO2 is 2C to 4.5C, we should have seen a 2C increase in temp. in the last 40 yrs due to 4% increase in H2O. Why is earth not warming fast enough?
    Moderator Response: [Dikran Marsupial] Welcome to Skeptical Science! There is an immense amount of reference material discussed here and it can be a bit difficult at first to find an answer to your questions. That's why we recommend that Newcomers, Start Here and then learn The Big Picture.

    I also recommend watching this video on why CO2 is the biggest climate control knob in Earth's history.

    Further general questions can usually be be answered by first using the Search function in the upper left of every Skeptical Science page to see if there is already a post on it (odds are, there is). If you still have questions, use the Search function located in the upper left of every page here at Skeptical Science and post your question on the most pertinent thread.

    Remember to frame your questions in compliance with the Comments Policy and lastly, to use the Preview function below the comment box to ensure that any html tags you're using work properly.

  39. Arctic icemelt is a natural cycle
    Schmidt's other comment is also worth repeating. " This is mostly about a quantification of the size of internal variability. By looking at multiple runs with the same forcing and looking at the variability in short trends, you can make a statement about the range. The current trend is at the edge of what the NCAR runs show, and so it is conceivable that what we are seeing has been a weaker forced trend, combined with a (stochastic) increase to the trend because of internal variability. With that assumption, one can look at the other simulations and calculate the likelihood of the stochastic component going the opposite way and slowing down the observed trend. But these likelihoods rely on the NCAR model's estimates of both the forced trend and the internal variability being correct. The former is less likely than the latter"
  40. Dikran Marsupial at 16:59 PM on 18 August 2011
    How we know an ice age isn't just around the corner
    Dr. Doom It is worth bearing in mind that SkS is a site designed for communicating science to the general public. It is therefore reasonable to use the term "ice age" in its colloqial sense, rather than as its strict geological jargon meaning. There is a fine line between precision and pedantry, and it is important to consider the intended audience. Anne Maries' title is perfectly reasonable.
  41. Dikran Marsupial at 16:43 PM on 18 August 2011
    Understanding the CO2 lag in past climate change
    Dr Doom The reason there isn't an upward spiral is because (i) the radiative forcing due to CO2 is only logarithmic in the concentration and (ii) the uptake of CO2 by the oceans depends on the difference in partial pressure between surface ocean and air as well as on the temperature of the surface ocean, the higher the partial pressure in the atmosphere, the more difficult it is for the oceans to de-gass and the easier it is for CO2 to go from the atmosphere into the surface oceans. This means that there comes a point where a new equilibrium is reached and the temperature stops changing (until the forcings change again). This is the negative feedback to which you refer (although it only becomes stronger as CO2 levels rise).
  42. Another two reviews of Climate Change Denial
    The guys name is brian and he is at brians-satchel.com
  43. How we know an ice age isn't just around the corner
    Anne Marie, An ice age isn't just around the corner because we are still in an ice age. I'm sure you know that we are in the Quaternary Glaciation that started 2.58 million yrs ago. That's why we still have ice sheets in Antarctica and Greenland. Despite recent global warming, temp. today is one of the coldest in 600 million yrs. For most of geologic history, earth's temp. was above 17C.
  44. Understanding the CO2 lag in past climate change
    Anne Marie, If temp. drives CO2 and then CO2 also drives temp., then they reinforce each other and should result to upward spiral and runaway greenhouse effect. Why didn't that happen? If past climate change was dominated by reinforcing positive feedbacks, why did the warmings stopped and reversed into coolings so many times? What was the cause of the reversals? There must have been a stronger negative feedback or stronger negative forcing at work.
  45. mullumhillbilly at 15:33 PM on 18 August 2011
    It's waste heat
    Muon@ 76. Yes I am new to posting on this site, and I assure you I'm not a reincarnation of any previous posters. I am wading through the long "waste heat" thread you referred to earlier; I didnt know it existed when I first posted here... bit confusing I think having two threads on the same topic. As to sticking to the science, that's what I am attempting. This site is, after all, called "Skeptical Science", so I think its appropriate to ask questions, no? Sorry about the caps, I haven't discovered how to use bold or italics here, and didnt think it was even possible except I see that Tom in 77 has just done so. I'm happy to take the glasshouse questions elsewhere if you can suggest the appropriate place. Tom@77. I did say "in equilibrium with their surroundings", but didnt mean that to include the entire galaxy :-). Both glasshouses start cooling when the sun's forcing stops. I accepted that the CO2 enriched glasshouse (Gh.8x) cools more slowly than the control (Gh.1x). But sometime before dawn the temperature and heat content of both glasshouses is the same, ie they both get to equilibrium with their (local) surroundings. Put an open-top thermos flask with warm water and a cup of same volume of warm water into a fridge and wait. The thermos will stay warm for longer but it won't be long before they are both the same temperature. So, the Gh.8x can only slow down the cooling briefly, but eventually comes into equilibrium with the ambient fridge air. Would you agree? I'm not questioning the existence of a greenhouse effect per se, but I am questioning whether a short period of less-than-normal overnight cooling is in fact "climate change", notwithstanding that "average" temps appear to be higher. I'm not sure why the experiment is invalid due to size alone, but let's assume that the Gh's are at least tall enough to intercept >99% of the intial LWR emitted from the surface (100m ?). The delayed outward radiation is real, but eventually the retained energy makes its way to the Gh walls/ceiling, and is transferred to outside the system. In the real world, the energy makes its way to TOA whether via convection or radiation) and ditto..is transferred to outside the system. "Climate change" (as opposed to simply increase in average temperature readings over time) requires that some of that energy stays in the system. Can you point me to anywhere that empirically demonstrates or explains why it takes more than a few hours on average, for the retained energy to make its way to TOA and get lost from the system?
  46. Arctic icemelt is a natural cycle
    Here's a new model study, http://www2.ucar.edu/news/5124/arctic-ice-melt-could-pause-near-future-then-resume-again Up and/or down for the next few decades, multiple factors at play. This doesn't quite gel with previous reporting does it?
    Response:

    [DB] "This doesn't quite gel with previous reporting does it?"

    I doubt that you care to elaborate on your implication here, as I'm pretty sure where you're coming from (and it won't pass the Comments Policy prohibitions).

    Needless to say, that's old news, I'm afraid.  Discussed extensively already at Neven's and RC.  Per Gavin:

    This is not particularly relevant for current behaviour though. More important is how good the aerosol forcing is, or the indirect impacts of black carbon etc. - but we don't know the real answer. - gavin

    Note the bit about "not being relevant for current behavior"...because the ice is currently disappearing in the Arctic 4 times faster than predicted by all models except Maslowski's (which is still tracking for his 2016±3 years).

  47. Joseph E. Postma and the Greenhouse Effect Part 2
    The thing about siding with Science is that it will sometimes lead you to conclusions that you find non-intuitive and difficult to accept. Siding with Fantasy will lead you anywhere you wish it to, except to reality.
  48. Climate Denial Video #3: Polluters Use Same Tactics As Tobacco Industry
    apirate @39, Neither I nor anybody else here at SkS has been trying to discount the opinions of the other scientists. I think it is very significant that while only 58% of the public think there is any anthro in the global warming, 76% of non-climatologists who are not actively engaged in research think there is; and that while 82% of scientists do, 88% of climatologists think there is anthro in the global warming, 89% of active publishing scientists and 91% of active publishers in climatology (regardless of discipline) agree. Clearly there is a gradation in this, with increasing expertise correlating with increasing agreement with the claim that "... human activity is a significant contributing factor in changing mean global temperatures". But that does not in anyway excuse a pretense that the opinion of the least expert scientists (with regard to climatology) is as important as the opinion of the most expert. Nor does it have any relevance to the question of whether there is a consensus of the experts on climate change. Nor do I an anyway discount the Oregon Petition or its significance. But what I refuse to do is to inflate its significance (as you are attempting to do) by ignoring the denominator. So 0.3% of technically qualified Americans will sign a petition against action on global warming if presented with a deceitful article deceptively packaged. Well, certainly that is significant, not because it suggests significant informed disagreement with the IPCC conclusions. It does not because the signatories are neither particularly well informed on the topic as a group, nor a significant number of technically educated people in the US. It does, however, show a significant failure by many technically trained people to use critical thinking when it comes to climate change.
  49. It's waste heat
    mullumhillbilly @74, your experimental design would not work because: (a) you have not controlled for back radiation; and (b) the CO2 atmosphere in your experiment would have approximately the same temperature as the surface, thus precluding any greenhouse effect. In contrast, in nature there is no back radiation from space, and the CO2 in the upper troposphere (from which most IR radiation absorbed by CO2 is reradiated to space is much colder than the surface of the Earth because of the adiabatic lapse rate. These two factors make it difficult (though not impossible) to model the greenhouse effect in a simple small scale experiment; a fact that has lead many people (including the Myth Busters) to develop essentially flawed experiments. Despite that your thought experiment is an interesting approach. However, you cannot apply it to the macroscale as you do. The systems you describe "equilibriate" when average energy in matches average energy out. However, the energy in at night consists of the cosmic microwave background radiation (<< 1 W/m^2), the geothermal heat (0.1 W/m^2), and industrial waste heat (0.03 W/m^2) plus a few very minor terms from meteor impacts, cosmic rays and the like. That means to reach equilibrium the temperature would need to drop to less than 65 degrees K (less than - 208 degrees C). The lowest temperatures on Earth are found in the Antarctic in winter, when it sometimes drops to -100 degrees C, but even there, equilibrium night time temperature is never reached. Six months of darkness is not enough to reach an equilibrium night time temperature on the surface of the Earth. Only a minority of the thermal inertia that means equilibrium night time (or day time) temperatures are never reached on Earth are a consequence of the greenhouse effect. But it certainly means heat from the greenhouse effect can accumulate from day to day, and year to year.
  50. It's waste heat
    mullum#74: Try this thought experiment. The topic of this thread is waste heat. Your glass greenhouses are of no relevance. But you're already in full-fledged GHE/AGW denial mode, consistent with some posts under the same name on other blogs. SkS runs a bit differently than those blogs: I suggest a thorough review of the various policies here, including the Newcomer's Guide and especially the Comments Policy, where you will note some language advising against using all caps. Use the Search function to find a thread of interest and pose questions relevant to the thread. There are nearly 170 skeptic 'arguments' addressed in considerable detail. Most important of all, you won't get away with denying the evidence, as in: "With no accumulating energy gain, there is nothing to drive the hurricanes, floods, droughts, heatwaves, snow dumps, melting ice etc etc". A general principle of science is this -- if you have a premise (in your case, there's no climate change) that conflicts with multiple lines of evidence, your premise is probably incorrect. Stick to the science; avoid forming opinions based on speculation about pots of water, balloons, sheets of plywood in the sun and glass greenhouses.

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