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Comments 109501 to 109550:

  1. The contradictory nature of global warming skepticism
    Baz, so essentially... By carefully cherry picking the start and end points, and/or citing false values for the data, you can come up with a situation where the warming is 'only' 0.12 per decade (i.e. 1.2 C total by 2100 IF we assume no acceleration)... which you can then falsely describe as "flat"... and on that basis you can then falsely say that this is sufficient to 'disprove man made global warming'. Where's the heat? Gee, I dunno... hottest decade in the temperature record; 2000-2009. Second hottest; 1990-1999. Third hottest; 1980-1989. Are we seeing a pattern here? You seem to be arguing that if AGW theory is correct then the temperature would have to increase at a near constant rate... which, of course, is completely contrary to AGW theory. Of course the rate of increase will fluctuate with various other conditions... such as the current prolonged lull in solar activity. As to there having been "no volcanoes" since 1995... absurd on its face. Tell it to all the people who couldn't fly in Europe earlier this year because of the eruption in Iceland. BTW, you're also wrong about CO2 emissions being higher than ever... they actually dropped a bit the past couple of years due to the global recession. Finally, let's compare two of your recent statements; Baz #277: "BTW, I've 'ignored' no other's comments other than yours" When I pointed out that this was false as you'd ignored my comments in #39 and #105 (amongst others) the response was; Baz #290: "BTW, you didn't ask me any questions in 39. I HAVE made an effort to respond to genuine questions." So... you switched from having answered all COMMENTS to having made an effort to respond to QUESTIONS. Except, of course, you didn't respond to my questions in #105 either. You're falling short even when you move the goalposts.
  2. A South American hockey stick
    #43:"the CLOUD experiment " Philippe: Thanks for that link. This is wayyy off topic, but since it came up here: Upon reading the paper, there is some lingering confusion over what they are doing: During selected periods, the chamber was exposed to a 3.5 GeV/c positively-charged pion beam from a secondary target. Pions of this energy correspond closely to the characteristic energies and ionisation densities of cosmic ray muons penetrating the lower troposphere. Minor editorial nit pick: GeV/c is a momentum, not an energy; the energy would be 3.5 GeV. We all make typos. Muon energies range from 6 GeV near the top of the atmosphere to 4 at ground, losing energy to ionization - a process that is continuous. Because of the high flux of muons (~1/cm^2 per minute at the surface -- see link above) due to solar cosmic rays, if muons alone were cloud-formers, we'd live in a sea of clouds. Yet the experiment was designed to study galactic cosmic rays: The present results, while suggestive, are insufficient to unambiguously establish an effect of galactic cosmic rays on cloud condensation nuclei, clouds and climate, ... Experiments are planned for the CLOUD facility at CERN to resolve this deficiency. With GCRs, we typically speak of much higher energies and that was the original pitch for enhanced ionization. Here is a very readable blog post on GCRs. I did a very preliminary analysis of online high energy events from the Auger detector; there is a slight increase in frequency during the sunspot minimum of 2009. Anyone note any increased cloudiness during that time?
    Moderator Response: Everybody who wants to discuss this further, please do so on the thread of the skeptic argument It's Cosmic Rays".
  3. Global warming and the unstoppable 1500 year cycle
    @Tom: "You even quote from the paper saying that the warming barely shows up in the Southern Hemisphere! However, I couldn't read the full paper so you may have something I missed." I couldn't read that paper either, but I got curious and searched for thingadonta's quote ("The pattern in the Southern Hemisphere is different, with slow warming and much smaller temperature fluctuations") on Google. The first result to come up was this very thread (thanks, Google's fast indexing). The second was a Wikipedia article (last revision Sept. 8) on Dansgaard-Oeschger events: http://en.wikipedia.org/wiki/Dansgaard-Oeschger_event#Causes Voelker's paper is cited on that page. Note that D-O events occured during the last *glacial* period, which would render thingadonta's argument nil since we are now in an interglacial, so his example doesn't apply.
  4. A South American hockey stick
    Re: RSVP (37)
    "I went to the link and could only read the abstract without paying for the actual article."
     Link to the full source provided in comment 4 above. The Yooper
  5. Himalayan Glaciers: Wrong Date, Right Message
    In the WG1 report of IPCC AR4, Chapter 4 "Observations: Changes in snow, ice and frozen ground" included a review of the state of glaciers (Cogley was a contributing author there), but not their future outlook. The global summary of future outlook of glaciers is included in Chapter 10 "Global climate projections", in particular section 10.6.3, in the context of sea level change. Glaciers were not discussed in Chapter 11 "Regional climate projections."
  6. Should The Earth Be Cooling?
    Re: Ken Lambert (56)
    "Ned's Chart at post #18 here: http://www.skepticalscience.com/The-Pacific-Decadal-Oscillation-and-global-warming.html shows smoothed GISS land + SST and RSS temperatures which sure looks like flattening over the last 8-10 years. That's if a clear reduction in the slope of a curve is flattening - which for most people it is."
     Are we even looking at the same graphic? The overall trend (1900-2010, 1980-2010) is UP. Perhaps your razor-focus on statistically insignificant timescales blinds you to that fact. Most people would care to be ACCURATE in their statements and assertions and would note that fact. You are WRONG.
    "SLR flattening by nearly all analyses"
     Um, no. Wrong again. Here's what it actually looks like over that interval (from Tamino, reproduced from the University of Colorado site). You mistake natural variations of noisy signals over statistically insignificant timeframes for "flattening" (is that the new meme de jour?). You are CHERRY PICKING. You also make unfounded assertions with NO analysis of your own to support your baseless claims.
    "And all this at a time when the last decade of theoretical CO2GHG forcing 'has been the highest decade' since the last ice age. Sound familiar?"
     There's nothing "theoretical" about the greenhouse gas effects of CO2. It's all reproducible in the lab, and has been since the 1800's. Did you not take science classes in school? You are correct in that CO2 concentrations have been at their highest levels in millennia; the "aughts" are hotter than the 90's, which were hotter than the 80's which were hotter than the 70's, and this year is the hottest year ever (thus far). Note the trend here. You waste all of our time, and that of the readers here as well. Gimme something of substance, some meat and potatoes, to work with here. I'd LOVE for you to be right, but so far you're just statistically significantly "flattening" your credibility. Sound familiar? The Yooper
  7. Philippe Chantreau at 23:42 PM on 19 September 2010
    A South American hockey stick
    I get your point Muoncounter but, still, what matters is how much of a difference in radiative forcing this translates into. These images are also snapshots, how does it average over time? You'd expect concentrations to be slightly higher, as they are observed, near the regions where the most fossil carbon is burned. However, it remains that even very far from these regions the concentrations are not so drastically different that you can't say the CO2 is overall well mixed.
  8. Should The Earth Be Cooling?
    Here's the thing. Over the last 30 years, the planet's been experiencing according to skeptical theory...
    • Cooling from a decline in solar irradiance
    • Cooling from a decline in the PDO
    • Cooling from planetary orbital shifts
    • Cooling from increased cloud cover dervived from cosmic rays
    • Cooling from increased cloud cover from a negative water vapor feedback
    • Cooling from increased cloud cover derived from "biosol" nuclei
    • Cooling from increased cloud cover derived from iodocompounds
    • Cooling from increased cloud cover derived from biologic dimethyl sulfide
    • Cooling from cloud compositional changes derived from the iris effect
    • Cooling from anthropogenic aerosols and soot
    • Cooling from atmospheric aerosols from COS and other natural emissions
    • Cooling from changes to the Meridional Overturning Circulation (MOC)
    And yet temperatures have continued to rise over that time period, and the most that can be claimed is not cooling but a "flattening over the last 8-10 years". If this is the result of so many natural mechanisms opposing the anthropogenic warming signal, what happens when their natural cycles reinforce that signal?
  9. Philippe Chantreau at 23:33 PM on 19 September 2010
    A South American hockey stick
    Ah, HR brings up the CLOUD experiment again. The source for that is Duplissy et al (2010). Available here: http://www.atmos-chem-phys.net/10/1635/2010/acp-10-1635-2010.pdf The experimental design left some to be desired: "The large observed growth rates indicate the presence of additional trace vapours in the aerosol chamber, whose identity is unknown but for which there is indirect evidence of background organic vapours. The presence of background vapours is also inferred from the observation that small (of order 0.1C) increases of temperature invariably trigger nucleation bursts, which is attributed to the release of unknown vapours from the chamber walls." The conclusion is not very, well, conclusive, as in: "However, during most nucleation events, the contribution of ion processes appeared to be minor" End word:"In summary, the exploratory measurements made with a pilot CLOUD experiment at the CERN Proton Synchrotron have validated the basic concept of the experiment, provided valuable technical input for the CLOUD design and instrumentation,and provided, in some of the experiments, suggestive evidence for ion-induced nucleation or ion-ion recombination as sources of aerosol particles from trace sulphuric acid vapour at typical atmospheric concentrations." Since Svensmark was involved in the paper, it is no surprise these words are found, but in fact there is very little there to hang on. Suggestive evidence. I like to be a skeptic too. Suggestive evidence does not impress me much.
  10. The contradictory nature of global warming skepticism
    289. Sorry, that should say, "would give a positive 0.12 c per decade". (which isn't statistically significant)
  11. The contradictory nature of global warming skepticism
    BTW, you didn't ask me any questions in 39. I HAVE made an effort to respond to genuine questions.
  12. The contradictory nature of global warming skepticism
    CBD. I could have chosen 1995 to 2009, which would give a negative 0.12 c per decade. Or I could have chosen the past 10,000 years, or...whatever. Including in a year or few years introduces wildly different per decadel trends, which makes them jump from statistically-significant to insignificant. The past few years have also seen no volcanoes to add any cooling effect. If there had been, then we’d be looking at negative decadel trends. This at a time when CO2 emissions have never been higher. Where’s the heat, CBD, where’s the heat? With no volcanoes the global temp should be ramping up and away. Why isn’t it, CBD?
  13. Global warming and the unstoppable 1500 year cycle
    "The 1500-year cycle in question ": In the discussion of Moberg 2005 in the MWP: Rhetoric vs Science thread, we saw hints of a long period cycle. The amplitude of that cycle appeared to be less than 0.3 degC; the current increase above that cycle is already 0.8 degC -- and climbing. The cycle is broken; thus the skeptic argument based on that cycle is also broken. So to counter broken hockey stick? Broken cycles!
  14. Global warming and the unstoppable 1500 year cycle
    I often see "skeptics" protest saying "hey, no one said the warming is not happening... we're just questioning its cause!" On the other hand, there are no-warming related arguments all around. It's Urban heat island effect, glaciers are not shrinking, Antarctica is gaining ice, the "hiding the decline" email and so on. I never saw a "skeptic" protest in one of those denier blogs and say "Come off it man! We know it's warming!" "Skeptics" are very flexible when they make their arguments.
  15. Should The Earth Be Cooling?
    Daniel Bailey (The Yooper?) and kdkd I will repeat this for you both gentlemen: Ned's Chart at post #18 here: http://www.skepticalscience.com/The-Pacific-Decadal-Oscillation-and-global-warming.html shows smoothed GISS land + SST and RSS temperatures which sure looks like flattening over the last 8-10 years. That's if a clear reduction in the slope of a curve is flattening - which for most people it is. Some facts please kdkd - your derogatory comment can be vented elsewhere - we are trying to keep ad hominem attack out of this blog. Just to repeat some 'multiple independent lines of evidence' - temperature flattening, SLR flattening by nearly all analyses, and OHC flattening or nil by the imperfect but best we have Argo; and Dr Trenberth can only find 60% of the 'missing heat' which has probably gone missing forever. (It has not only left the building - but probably left the planet!) And all this at a time when the last decade of theoretical CO2GHG forcing 'has been the highest decade' since the last ice age. Sound familiar?
  16. Climate change: Water vapor makes for a wet argument
    CBDunkerson at 19:58 PM, for CO2 the carbon cycle starts and finishes at the earths surface. That requires that every 3 to 4 years the equivalent amount of the entire CO2 content of the atmosphere rotates through the various sources and sinks at the surface, passing through those few centimetres both in and out, which is probably where it also either absorbs or releases most of the thermal energy it carries as it circulates. The seasonal variations also show that CO2 levels vary around 20 to 40ppm or even more over the course of the year, remembering that the CO2 released through the burning of fossil fuels is only about 1/30 of that released by natural processes. In addition to the offset in the timing of release and increased sequestration, the location of the sources and sinks may be far apart. If sea surface temperatures are a factor in whether CO2 is being released or sunk, then the circulation and concentration levels may be quite convoluted and as variable, but more difficult to track then say local temperatures, wind speeds and precipitation. Further, given the direct warming effect of CO2 is quite small, and it is the amplifying effect of water vapour that produces most of the greenhouse effect, with the quite large variations in CO2 concentrations throughout the annual cycle, then if water vapour is as sensitive as it is thought, then one would expect the variations in water vapour to respond with even larger amplified responses that then flows through to increased variations in clouds in both volume and distribution.
  17. Global warming and the unstoppable 1500 year cycle
    Thingadonta: "Firstly and generally, you are grouping together and over-simplifying skeptical arguments in order to more easily label and discredit them. This is a common straw man technique." Yes, I agree with this and it annoys me to see it on this site. Although there are a lot of people who deny the warming, my understanding is that most skeptics believe there is a natural warming. Of course, that doesn't stop them from simultaneously saying that Arctic ice has recovered, or that warming stopped in 1998... "Secondly, (nearly all) skeptics do not reject the greenhouse effect. Once again, they disagree about the relative degree and rate." But they might as well reject it entirely, seeing as the end conclusion is that our CO2 emissions don't matter. The "to a relative degree" part of their argument comes across, to me, as just trying to appear more reasonable while still embracing their politically-motivated views on emissions cuts. "You are also wrong about the 1500 cycle being limited to the Northern Hemisphere." Unless I'm misinterpreting the text of the abstract, it seems to contradict what you say about it: "The spatial distribution of all records is biased towards the northern hemisphere, for the marine records especially towards the North Atlantic region. Terrestrial records cluster in western Europe, the western United States, and China." You even quote from the paper saying that the warming barely shows up in the Southern Hemisphere! However, I couldn't read the full paper so you may have something I missed. "Your are also wrong in stating "And unlike natural heat variations the current temperature increase caused by CO2 is being recorded occurring all around the globe – on the ground, in the air and in the oceans." "Natural heat variations" is an awfully vague statement and could refer to a lot of things, but it probably refers to the 1500-year heat variation being discussed here. Which, as I believe you have failed to demonstrate to the contrary, was mainly limited to the Northern Hemisphere. But yes, there are natural warming mechanisms that are global so may the text should be changed slightly. Greenman3610's video on YouTube does a good job at addressing this claim, in fact it may even do by itself instead of this text summary (no offense to John Russell though, he made a good effort):
  18. Global warming and the unstoppable 1500 year cycle
    S. Fred Singer wrote the book on this subject but as we all know, Fred Singer is a lot like George Costanza.
  19. A South American hockey stick
    @31 HumanityRules <"I> About 1/3-1/2 of 20th Century warming is anthropogenic". Another assertion with no sources to back it up.
  20. Global warming and the unstoppable 1500 year cycle
    There's also the simple, it wasn't warming 1500 years ago answer too...
  21. A South American hockey stick
    #29 & #40: Why not go right to the source? click for full scale at source page Change to 'global' 12-31-08 At the time of that image the N/S total variation was indeed about 15 ppm. In the first image in the global data set, 1/1/01, it was only 8 ppm. So the discrepancy between hemispheres has doubled in 9 years? That's no natural cycle. And 15ppm? At 395ppm, the delta F is 1.84; at 380ppm, delta F is 1.63, a difference of 11%. Seems like a lot.
  22. beam me up scotty at 21:41 PM on 19 September 2010
    Should The Earth Be Cooling?
    The arctic is screaming global warming. Skepticism is looking more and more like proselytization. How about this site expanding its scope to include the debate about what we should do about it? Pros and cons of geoengineering Carbon capture State of the art modeling Regional forecasting etc.
  23. What's happening to glaciers globally?
    Riccardo you are correct that just substantial accumulation zone thinning is enough to forecast glacier survival. You want a more sophisticated measure. However, the goal is a simple measure that can be easily applied to all glaciers simply with decent repeat satellite images, or a map and a satellite image. If we make it to sophisticated such as a ratio of thinning to changes in velocity in the accumulation zone we make it difficult to apply. HR good question about the UNEP graph. The WGMS 30 reference glaciers goes back to 1980. Reference network. If they move the start date to 1985 they will be able to expand to up to 45. If they move the start date for the group back to 1946 they will only have 2 to choose from. Only one Storglaciaren in Sweden is in the reference group. In 1949 Sarennes Glacier, France and Storbreen, Norway are added. Thus, the WGMS record for the 1945-1955 period relies on only a couple of glacier and is not useful for a global summary. The graph UNEP has reports only the Storglaciaren data at first, look at Mass Balance Bulletin 10 page 13 for that glaciers graph and compare. Look at page 1-4 for the list of glaciers and years examined, some of the records are not complete from the first to the last year. This is our best mass balance data. There are other glaciers like the Taku Glacier in Alaska where mass balance work began in 1946 that is not part of the WGMS reference glacier system. This is because before this record publishing this record in 1990 I waited for satellite verification of its accuracy. In the section of BAMS state of the Climate 2009-for glacier mass balance-which I authored-we were asked to provide the mass balance data records for previous data periods. Note the WGMS actual reported record, which is absolutely the best, but it only goes back to 1980. WGMS. Before that Cogley who first contacted me about the global glacier mass balance record more than a decade ago, has the best. He has used Geodetic data not just directly measured data. This is data based on volume change determined from repeat mapping, usually via photographs. This work typically does not provide an annual measurement, as annual photographs tend to be rare. It does provide an accurate record for longer time intervals. If you look at Cogley's 2009 Figure 2 you will note that until 1930 and the advent of aerial photography the record is scant. The mass balance record from 1850-1950 will be improved, but Cogley for now has provided the best analysis. There are many more glaciers that we can and will add to a longer term glacier mass balance record since 1950 using geodetic assessment. Think of comparing a glacier today in a satellite image with excellent mapping details to its original mapped state such as for Bear Glacier or Grasshopper Glacier. Is does match the results of Oerlemans (1999) also. That record based on terminus changes is also useful.
  24. It's El Niño
    Please read:http://climatechange1.wordpress.com/2010/08/17/is-enso-rather-than-a-%E2%80%98greenhouse-effect%E2%80%99-the-origin-of-%E2%80%98climate-change%E2%80%99-by-erl-happ/ Tell me this: What is responsible for the long term change in the differential pressure that drives the trade winds and tropical temperature?
  25. Global warming and the unstoppable 1500 year cycle
    I guess this is the problem with some basics versions , its to easy to pick apart becuase it is not detailed enough . Basic versions are just trying to outline an Idea and I think its hard not to generalise otherwise it would become longwinded and hard to give a quick rebuttal while standing on the train .
  26. beam me up scotty at 21:23 PM on 19 September 2010
    Global warming and the unstoppable 1500 year cycle
    "Skeptics" use bits of science like flack to deflect focus from their core arguments. In Thingadonta's case the core argument appears to be absent altogether. The core motive seems clear: impugn the credibility of the author.
  27. The contradictory nature of global warming skepticism
    Baz #287 wrote: "However, as I'm sceptical (because I've witnessed 10 years of flat HadCRUt data)" So you are 'skeptical' based on a false claim. Go figure. What's fascinating is that when you cite the numbers you start from 2001, which was less than ten years ago, round the anomaly values down, and wildly underestimate the 2010 value. The actual numbers are; 2000: 0.271 2001: 0.408 2002: 0.465 2003: 0.475 2004: 0.447 2005: 0.482 2006: 0.425 2007: 0.402 2008: 0.325 2009: 0.441 2010: 0.531 (so far) Drawing a trend line from the start and end points yields; 2000-2009: +0.17 C/decade 2001-2010: +0.123 C/decade Neither seems particularly "flat".
  28. Global warming and the unstoppable 1500 year cycle
    Thingadonta #1, Methinks you protest too much. Firstly, it is essential to group contrarians argument in bite-sized chunks so that they can be classified, even if that is not exact. Global warming is a single "inference to the best explanation" for a variety of phenomena. Contrarians try to refute some of the arguments while ignoring others, so that the collectivity of their efforts at refutation tend to be chaotic and contradictory. Contrarian Contradictions Secondly, the post does not say that most contrarians reject the greenhouse effect. Is said that SOME MUST DO SO in order to affirm a 1500 year climate cycle. Funny, your argument is actually what you are decrying - a strawman. About your third point, I will leave that for John.
  29. The contradictory nature of global warming skepticism
    Daniel, my opinions are worthless to you. I have a view on climate change which I have expressed here many times. However, as I'm sceptical (because I've witnessed 10 years of flat HadCRUt data) then this is worthless to you too. You may well point to other metrics as evidence, and that may be valid, but after all is said and done, I am sceptical that the future will be warm - based on those 10 years and the fact that we know so little about climate science. Now that may well be illogical to you, even irrational. That's fine, I can live with that, but you have to understand that people like me, who hover on the fence, and who will be swayed by a few year's worth of data, are the norm, the mainstream. We've both seen that very many people are swayed by one hot summer or cold winter! You're not going to change our view by pointing us to climate metrics that are still disputed by very eminent people. Let's be honest with each other, if ALL the scientists were on one side then to believe the opposite would be pretty obtuse. Take OHC as a classic example - with Pielke. So Daniel, the only 'evidence' I can offer you is the evident opposition to your beliefs by people like Pielke, Spencer et al. You may well rule these out of hand (although I wouldn't do that if I were you). The 'evidence' for my beliefs is that some very clever people say that we cannot be sure about future feedbacks. I have pointed this out many times Daniel, and I am a little weary that you say you're "still waiting". So I'll say it yet again. The evidence for my scepticism is that we don't know enough about the climate system. We must approach this with open minds - as I indicated before. We MUST be sceptical. That's not just good science, that IS science! We all show confirmation bias. It's quite evident on here. To contribute on a Creationist website (as I have many times) you go armed with your confirmation bias - it's impossible not to. But with Creationism we have a mass of reliable evidence against total faith and belief. Man-made climate change is NOT the same debate in different clothes; for here we have uncertainty and opposite opinion from very knowledgable people. I will respond to the other posters, but I will also say that I WILL continue to visit WUWT as well as realclimate. I have posted at WUWT and argued there - even pulling Anthony up once on the subject of CO2 emissions, to which he replied. If nothing else, then I urge you to use it as a reference source (like the link I gave for Arctic ice graphs), but also use it to read other's opinions (as I do with realclimate - though I've stopped posting there). Reply later when more time allows. All the best.
  30. Climate change: Water vapor makes for a wet argument
    johnd, are you arguing that small variations in CO2 level within a few centimeters of the surface play a significant part in global temperatures? That SEEMS to be what you are getting at... it just doesn't make sense. The whole reason CO2 is such a significant greenhouse gas (aside from its longevity) is that it spreads high up through the atmosphere. A thin layer has very little impact on temperatures... it is the huge altitude range that CO2 occupies which allows it to produce significant additional warming. Your 'few centimeters' of CO2 at the surface would produce an insignificant amount of greenhouse warming... almost all of which would also be produced by water vapor even if the CO2 weren't there. It's like arguing about the impact of a falling pebble while ignoring the rockslide behind it. That said, it should be understood that when readings show 390 ppm at various surface stations around the world and in satellite measurements at higher altitudes that is effectively the baseline CO2... the amount after it has been well mixed through the atmosphere. Regions downwind of major emissions areas will have that baseline PLUS some additional amount of CO2 which hasn't dispersed yet. So yes, there are localized variations in CO2, but only in that in some regions it is higher than the commonly cited values because it hasn't had time to mix through the atmosphere yet.
  31. Global warming and the unstoppable 1500 year cycle
    Your discussion above is wrong on several points. Firstly and generally, you are grouping together and over-simplifying skeptical arguments in order to more easily label and discredit them. This is a common straw man technique. But to your first point, most skeptics don't deny that global warming is happening. They disagree about the causes, rate and relative degree. Instead of positing it as (almost) exclusively a human-caused effect, they tend to think that natural effects in the last several decades, as well as in the broader term going back centuries, have been understated. Secondly, (nearly all) skeptics do not reject the greenhouse effect. Once again, they disagree about the relative degree and rate. They do not generally disagree about the cause of the greenhouse effect either, ie gases produced by human activities cause a trapping of heat; once again they disagree about the relative degree this effect has as a causative factor to observed climate changes, and how much these climate changes are natural (or in some cases just weather). You are also wrong about the 1500 cycle being limited to the Northern Hemisphere. Voelker, Antje H.L. (2002). "Global distribution of centennial-scale records for Marine Isotope Stage (MIS) 3: a database". Quaternary Science Reviews 21: 1185–1212 "The pattern in the Southern Hemisphere is different, with slow warming and much smaller temperature fluctuations" I suspect you are only referring to the cycle within integlacial periods, where the effect is weaker. During ice age cycles, the cycle has been found in both hemispheres, although with less T variation in the Southern Hemisphere. The reason for apparent effects being limited during interglacials to the Northern Hemisphere is probably due to lack of data in the Southern Hemisphere, much the same as arguments once put forward for the Medieval Warm Period, which is more and more being conclusively shown to show up in the Southern Hemisphere, as more data is gathered. Your are also wrong in stating "And unlike natural heat variations the current temperature increase caused by CO2 is being recorded occurring all around the globe – on the ground, in the air and in the oceans. Natural T variations like ice ages occur all around the globe, so I don't know how you can state the above. This must be some kind of record for this site, at least 3 major mistakes in one discussion.
  32. A South American hockey stick
    Daniel Bailey@29: Probably a better animated visualisation? http://youtu.be/l8tPKj20GFo
  33. A South American hockey stick
    Philippe@30: "Ok, but these variations span about 15-20 ppm. I don't know what kind of a difference in radiative forcing that makes but I'm guessing not that much." True! I suspect the differences between the hemispheres are a mixture of things, with some more dominant than others.
  34. A South American hockey stick
    33.Daniel Bailey 34.archiesteel I thought RSVP put forward a good discussion point. VTG wanted to ignore that discussion and instead wanted a definitive answer, I think that's were the silliness started. It's worth discussing natural variability in light of paleo-reconstructions. The discussion around these reconstructions tend to focus narrowly on the rather trivial point of whether todays temp is higher than 800 years ago. My understanding is there is more to be gained than that. I was being slightly flippant with my answer but that doesn't mean I think the numbers would be unrealistic. Jasper Kirkby @ CERN seems to think there is more to this question. Sorry to all concerned ;)
  35. A South American hockey stick
    "archiesteel at 12:37 PM on 19 September, 2010 @HumanityRules: why are you responding for RSVP? He's a grown man, he can provide his own answers (hopefully, it'll be better than yours)." To HumanityRules: Thanks for pointing out what the graphs clearly indicate. archiesteel I went to the link and could only read the abstract without paying for the actual article. The last sentence in the abstract refers to the detection of "unprecedented" warming in recent times. Imagine if you were in a hotel and expected to pay to hear a fire alarm.
  36. Climate change: Water vapor makes for a wet argument
    Daniel Bailey at 13:16 PM, that map is CO2 8km up. The reference earlier was to CO2 levels as measured at surface stations, and how it is transported by the weather systems. The mention in my post above of the micro-climate is also relevant to CO2 , given CO2 sources and sinks are generally at the immediate surface, so CO2 levels in the first couple of centimetres are likely to differ from those at higher elevations and be subject transportation by conditions in effect at those lower levels.
  37. A South American hockey stick
    @Lazarus
    Doesn't this research indicate that the MWP was global, or at least not restricted to the northern hemisphere?
    There's still a lot of spatial and temporal inhomogeneity, but it does seem by now that 950 - 1250 AD was particularly warm for most of the globe. This old skeptic map is worthwhile pouring over to see that inhomogeneity. Most proxy data indicate an MWP during the classic period, but others show cool temps for that time and warm peaks beyond the MWP. http://pages.science-skeptical.de/MWP/MedievalWarmPeriod.html (You can hover over or the graphs to expand them, and click on them to get more details)
  38. Climate change: Water vapor makes for a wet argument
    scaddenp at 14:54 PM, I think it is quite clear that the various processes that occur at the very surface and the few centimetres immediately above are not only very complex, but as yet not adequately understood or quantified. I would rate the status of such processes somewhat similar to those driving clouds, both in terms of complexity, and of current understanding, both of which are probably the most important processes of all when it comes to understanding climate change. As we have seen, what happens at the surface and immediately adjacent to it, is somewhat different to what happens just above it in the zone occupied by weather stations which have, and still do provide the basic data that allows both weather and climate to be quantified and analysed. The significance of this difference has not been lost on those who research agriculture, or indeed those who practice it. For them, it is the micro-climate, right at the earths surface that is important, that zone where solar radiation transfers it's energy to the soil and water, where evaporation takes place, NOT so much what happens 1.2m above where the weather stations are located which is above the zone in which most crops grow. If there is any nett transfer of knowledge between those involved in agricultural research, and those in climate research, I would not be surprised if it was from the agricultural scientists who research this micro-climate, to the climate scientists. The bare foot boy I mentioned earlier, was a proxy for the knowledge that those who are physically involved in the environment accumulate both by casual observation, and from a vested interest in what is really happening within that micro-climate, knowledge that many whose understanding of the climate comes from theories and formulas, and have not had the opportunity to relate what has been learned, to what is perhaps not so readily apparent without such a vested interest. With regards to the lack of freezing to death in ones backyard at night, that I imagine would be conditional on firstly the location of the backyard, and secondly that of the nights being shorter than 24 hours.
  39. A South American hockey stick
    Mann had near perfectly straight down trending shafts with a very obvious blade.
    I see less variability, but definitely not a straight line. It's also useful to read Mann 99 conclusions.
    "Although NH reconstructions prior to about AD 1400 exhibit expanded uncertainties, several important conclusions are possible, notwithstanding certain caveats. While warmth early in the millennium approaches mean 20th century levels, the late 20th century still appears anomalous: the 1990s are likely the warmest decade, and 1998 the warmest year, in at least a millennium. More widespread high-resolution data which can resolve millennial-scale variability are needed before more con dent conclusions can be reached with regard to the spatial and temporal details of climate change in the past millennium and beyond."
    Both the figures you show allow for far more natural variability than the contentious Mann hockey stick.
    Variability is... variable from study to study. You'd expect more variability at smaller scales - ie, globe v region, region v city etc.
  40. Climate change: Water vapor makes for a wet argument
    Re: johnd (126) Then try this one: The Yooper
  41. Climate change: Water vapor makes for a wet argument
    KR at 02:53 AM, I can't let you go without asking what is the relevance of the CO2 map. It does not represent measured CO2 distribution, but rather CO2 emissions attributed to human activity, so instead is basically a population density map.
  42. A South American hockey stick
    @HumanityRules: why are you responding for RSVP? He's a grown man, he can provide his own answers (hopefully, it'll be better than yours).
  43. A South American hockey stick
    Re: HumanityRules (31, 32) You waste everyone's time here by voicing opinions contrary to the consensus of knowledge and then fail to provide any source for those opinion. Baseless assertions. Hot air. Wasting time. I thought you were better than that. Disappointing. The Yooper
  44. A South American hockey stick
    ...... with nothing "in the pipeline".
  45. A South American hockey stick
    25.VeryTallGuy Please, quantify rather than assert ? About 1/3-1/2 of 20th Century warming is anthropogenic.
  46. The contradictory nature of global warming skepticism
    Re: Baz (277)
    "However, refusing to listen to an opinion opposite to yours is also natural, but dangerous."
     On the contrary, I listen to far more differing opinions than you realize. If it is supported by reason and citations that make sense, I am more than amenable to change my position. My position, based on a preponderance of evidence and facts, is that the globe (land, water, ice) is warming and we humans are causing it. I have spoken with many skeptical of this over the years. None have presented a coherent argument, let alone one supported by science. Personally, it was with great reluctance that, after weighing the evidence and the implications of the evidence, that I accepted AGW as an ongoing reality. I daily eagerly listen to alternatives, for the future that comes near now, is not one I would wish for anyone. And daily I am disappointed. I have listened to you, Baz. Weighed what you have had to say. Waited for the evidence to be provided to back up your opinions. And I'm still waiting. So unless you can provide some citations for me to weigh, all we have now is debate. And we both agree that is pointless. The Yooper
  47. Himalayan Glaciers: Wrong Date, Right Message
    SoundOff, if I recall correctly, there were some demands to include an estimate of this w/o the science being ready to answer as there was only one (Kotlyakov) paper present at the time that made this bold an extrapolation...
  48. Philippe Chantreau at 10:35 AM on 19 September 2010
    A South American hockey stick
    @ The Ville. Ok, but these variations span about 15-20 ppm. I don't know what kind of a difference in radiative forcing that makes but I'm guessing not that much.
  49. Himalayan Glaciers: Wrong Date, Right Message
    #12 archiesteel Isn't this ground enough for bannination? Most other "skeptics" who post here have their blind spots, like all of us, but they do seem to make an effort to stay on the right side of the signal/noise ratio. Thingadonta, not so much. To put it very politely indeed.
  50. A South American hockey stick
    Re: The Ville (28) To amplify on your NASA map, here's (because you reminded me of it) an animation showing the hemispherical contributions over time, in motion. Kinda cool to watch. The Yooper

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