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All IPCC definitions taken from Climate Change 2007: The Physical Science Basis. Working Group I Contribution to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change, Annex I, Glossary, pp. 941-954. Cambridge University Press.

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Comments 109201 to 109250:

  1. Climate Change: The 40 Year Delay Between Cause and Effect
    Thank you CB! Arkadiusz Semczyszak "Why Hasn’t Earth Warmed as Much as Expected?, AMS Journals, Schwartz et al., 2010.:" This paper discusses some uncertainty as to whether Climate Sensitivity is at the low range or whether aerosols contribute more to cooling than previously thought. But to understand fully what this paper suggests, you need to read the conclusions: "Even if the earth’s climate sensitivity is at the low end of the IPCC estimated ‘‘likely’’ range, continued emission ofCO2 at the present rate would exhaust in just a few decades the shared global resource of the incremental amount of CO2 that can be added to the atmosphere without exceeding proposed maximum increases in GMST. If the sensitivity is greater, the allowable incremental emission decreases sharply , essentially to zero at the present best estimate of climate ensitivity, and is actually negative for greater values of this sensitivity. "Reconstruction of the history of anthropogenic CO 2 concentrations in the ocean." Uncertainties as to the distribution of CO2 sink in the ocean does not change what we know about the carbon cycle and what content is in the atmosphere. The passage before what you quoted in the abstract says: "The release of fossil fuel CO2 to the atmosphere by human activity has been implicated as the predominant cause of recent global climate change1. The ocean plays a crucial role in mitigating the effects of this perturbation to the climate system, sequestering 20 to 35 per cent of anthropogenic CO2 emissions2, 3, 4. Although much progress has been made in recent years in understanding and quantifying this sink" "... and I have to invest billions of dollars in synthetic trees ... ?" Nothing you've posted here would lead anyone to not invest in mitigation and adaption.
  2. A detailed look at Hansen's 1988 projections
    Sorry Dana I didn't see you were the author. #70 is aimed at you.
  3. A detailed look at Hansen's 1988 projections
    Posted by dana1981 on Monday, 20 September, 2010 at 11:38 AM Had Hansen used a climate model with a climate sensitivity of approximate 3.4°C for 2xCO2 (at least in the short-term, it's likely larger in the long-term due to slow-acting feedbacks), he would have projected the ensuing rate of global surface temperature change accurately. Not only that, but he projected the spatial distribution of the warming with a high level of accuracy. OK, let's have a closer look. Hansen 1988 has also predicted the decadal mean temperature change for scenario B as a function of pressure and latitude. Now, since then we have got some actual data about this temperature trend distribution. The Hadley Centre of the UK Met Office has a near real-time updated dataset called HadAT (globally gridded radiosonde temperature anomalies from 1958 to present).
    Linear trends in zonal mean temperature (K/decade) in HadAT2 1979-2009. 1000 hPa data are from HadCRUT2v subsampled to the time-varying HadAT2 500hPa availability
    The image above is explained in this publication: Internal report for DEFRA, pp. 11 HadAT: An update to 2005 and development of the dataset website Coleman, H. and Thorne, P.W. As you can clearly see, predicted and observed zonal trends have nothing to do with each other: neither high, nor low level of accuracy can be detected. Particular attention should be payed to the cooling trend in the tropical mid-troposphere (-0.5°C/century) and the severe cooling between 65S and 70S along the entire air column (down to -5°C/century). These features are absolutely lacking in Hansen's prediction, therefore the take-home message should be "Hansen's 22 year old prediction is falsified". We can talk about if anthropogenic global warming theory were wrong on which the model was based or it was a flawed implementation, but there is no question about Hansen's failure. BTW, the tropical upper tropospheric cold spot observed and documented in HadAT2 is inconsistent with surface warming according to even the most recent computational climate models. So neither Hansen nor his followers can get the sign of change right in some particularly important regions. Taking into account this wider failure, we can safely bet "climate models and the anthropogenic global warming theory are wrong", quite independent of Hansen's 1988 blunder.
  4. A detailed look at Hansen's 1988 projections
    The other question I have is to do with scenario A, B and C. Having read the paper I'd sort of assumed that A was the "business as usual" option and the catastrophists really on this for the fearful future. Is this a wrong assumption on my part?
  5. A detailed look at Hansen's 1988 projections
    John, is there an assumption in your calculations that 100% of the temperature rise over this period is due to the forcing of human GHGs? Because the IPCC's "most" is starting to look like "all".
  6. Does Climate Change Really Matter?
    Re: cruzn246 (1)
    "There is no upswing in extreme weather."
     Your Jedi mind tricks won't work on us here. The Yooper
  7. Does Climate Change Really Matter?
    The effects you are most likely to experience is an increase in extreme weather. Actually, might it not be more likely that the effects most readers (who will be more likely to come from relatively rich developed countries with more moderate climates) will be the knock on effects of extreme weather elsewhere, experienced as economic turbulence and the political effects of food insecurity. But hard to know exactly what is going to hit a given person personally first. Some may experience extreme weather directly, but I suspect that many more will face knock on consequences of declining food production. That is, climate change will probably affect many people in ways that they don't think of as due to climate change, but it will be one of the significant background causes. @Roger A. Wehage Now I don't believe in God, so I tend to think that man was not created in His image and can therefore become extinct I do believe in God and tend to think that humanity was created in God's image, but I also think that we can become extinct. There is no divine promise of personal or civilisational protection.
  8. Arkadiusz Semczyszak at 23:47 PM on 22 September 2010
    Climate Change: The 40 Year Delay Between Cause and Effect
    Why Hasn’t Earth Warmed as Much as Expected?, AMS Journals, Schwartz et al., 2010.: “The observed increase in global mean surface temperature (GMST) over the industrial era is less than 40% of that expected from observed increases in long-lived greenhouse gases together with the best-estimate equilibrium climate sensitivity given by the 2007 Assessment Report of the Intergovernmental Panel on Climate Change (IPCC).” “Current uncertainty in climate sensitivity is shown to preclude determining the amount of future fossil fuel CO2 emissions that would be compatible with any chosen maximum allowable increase in GMST; even the sign of SUCH ALLOWABLE FUTURE EMISSIONS IS UNCONSTRAINED.” Ensemble reconstruction constraints on the global carbon cycle sensitivity to climate, Frank et al. 2010, Nature : “But themagnitudeof theclimate sensitivityof theglobal carboncycle (termed c), and thus of its positive feedback strength, is under debate, giving rise to large uncertainties in global warming projections.”. “The average correlation between individual temperature reconstructions and the mean CO2 record is 0.47 over the pre-industrial 1050–1800 period (all years are AD), increasing to 0.57 with a 50-year CO2 response lag—such timing is consistent with modelled CO2 response to a temperature step change.” “Yet, great scatter in c, from a few to more than 40 p.p.m.v. per uC, closely reflects the choice of the individual temperature and/or CO2 estimates used for analysis. Particularly relevant to constraining sensitivities of the Earth’s coupled climate system is the amplitude of hemispheric to global-scale ...” “Approximately 40% of the uncertainty related to projected warming of the twenty-first century stems from the unknown behaviour of the carbon cycle, which is an important component of the global climate system.” “Coupled carbon–climate models show a wide range in feedback strength, with 20–200 p.p.m.v. of temperature-driven CO2 by 2100 ...” “Our results ... ... suggest 80% less potential amplification of ongoing global warming.”. Reconstruction of the history of anthropogenic CO 2 concentrations in the ocean. Khatiwala et al. 2009.: “Although much progress has been made in recent years in understanding and quantifying this sink, considerable uncertainties remain as to the distribution of anthropogenic CO 2 in the ocean, its rate of uptake over the industrial era, and the relative roles of the ocean and terrestrial biosphere in anthropogenic CO 2 sequestration.” Summarize: ... such allowable future emissions is unconstrained ..., ... large uncertainties in global warming projections ..., ... great scatter ..., ... 40% of the uncertainty ..., ... wide range ..., ... 80% less potential amplification ..., ... considerable uncertainties ... ... and I have to invest billions of dollars in synthetic trees ... ?
  9. Climate Change: The 40 Year Delay Between Cause and Effect
    Following on Riccardo's comments and going back to the 'pot of water' analogy... Pinatubo was the equivalent of turning the stove off for several seconds. All that dust in the air had an immediate impact on temperatures, but within a couple of years it had all fallen back to the surface and was no longer a factor. Yes, less heat went into the oceans during those few years and thus there is also a 'long term' impact, but since the 'forcing' from the dust only lasted a short time the cumulative cooling effect was small. When you add CO2 to the atmosphere the level stays elevated and thus continues to build up greater heat which circulates around in the oceans for decades before making its way to the atmosphere.
  10. Should The Earth Be Cooling?
    #65 Handsome concession Yooper. Look forward to engaging on the details.
  11. Climate Change: The 40 Year Delay Between Cause and Effect
    muoncounter and sleepership, the meaning of lag is not that the response starts whith a delay, but that the full effect will be seen later. If we apply a constant forcing equivalent to that of Pinatubo eruption, for example, it will cool much more than what we've seen; it cooled a few tenth of a degree just because it was very short (in time) and because of the inertia (lag) of the climate system.
  12. Climate Change: The 40 Year Delay Between Cause and Effect
    grypo, well the study found statistically significant (greater than 97.5% confidence) warming of deep ocean basins (below 4000 m) in the Southern ocean all the way down to the sea floor. That should put to rest arguments that heat can't possibly be making its way into the deep oceans quickly enough to be responsible for discrepancies in the energy and SLR balance calculations. However, the amount of data gathered for this study is not sufficient to develop a robust GLOBAL picture of deep ocean warming. They make a good case that deep ocean heat needs to be accounted for in the energy and SLR budgets, but can't show that these make up the current budget gaps. With the available data they estimate 0.027 W/m^2 and 0.1 mm/yr global impacts from the sampled deep basins.
  13. Climate Change: The 40 Year Delay Between Cause and Effect
    CO2 @ 390ppm- do we see immediate effects? Was the heat the planet experienced this summer from 1980 C02 or from recently? If from 1980- when CO2 was just passing 350ppm- then we are in deep deep trouble when today's levels overcome the 'inertia' around the year 2040. The ice melt in the arctic seems over the last few years seems at the level of CO2 of between 370-390ppm however. It seems that by 2020- an ice free arctic ocean is certainly possible- and that would see the CO2 lag from 1990 around 360ppm- but I assumed that an free arctic in the summer would be the product of a co2 level of 390 +---- All interesting- the 'Inertia' of lag time in warming seems possible in feedback's and general warming- but as far as Ice melt- the arctic is responding to the levels we currently have.
  14. Climate scientists respond to Monckton's misinformation
    Ken #27, yes Monckton is just an eccentric extremist... who climate skeptics chose to represent their position before the US Congress. As to 'why people would oppose false views arguing against dealing with a dangerous problem'... gee that's a tough one.
  15. Climate Change: The 40 Year Delay Between Cause and Effect
    There is a new paper out from NOAA on deep ocean temperature measurements and I’m wondering how significant its findings are. Warming of Global Abyssal and Deep Southern Ocean Waters Between the 1990s and 2000s: Contributions to Global Heat and Sea Level Rise Budgets I can’t find any other work that covers the deep ocean over the globe. My questions are: 1. Is there any other study that measures that deep over the globe? 2. Understanding the caveats and assumptions, how much does this help in filling out Earth’s energy budget (Trenberth’s travesty)?
  16. Climate Change: The 40 Year Delay Between Cause and Effect
    "With 40 years between cause and effect" This is perplexing. I see the role of thermal inertia as a mechanism for delayed heating response, but I have to wonder about what happens in the other direction. As is well known, the '91 Pinatubo eruption produced both a short-term cooling and flattening in the rate of increase of atmospheric CO2 (see Robock 2003 and the MLO mean rate of change table. Why no lag in this case? Would such a large volcanic event be too short-lived to even make a dent in the lag you discuss here?
  17. It's a 1500 year cycle
    Re: daniel (7 and 8) Merely asserting something could be wrong and alleging impropriety doesn't make it so. If you have something of substance that will stand peer review that supports your allegations - bring it on. Or better yet, publish it. I'm sure you'll find many "skeptical" organizations will be glad to provide you with technical copywriters to assist you as well as financial support for your time to do so. Just remember to document your sources and provide links as well... I also suggest you actually do a little research on the background of paleo temperature records. Here's just one place to start. There are many more. In the meantime, you're blurring the line between skepticism and denial.
    "Is "Climate science" really science?"
    Hence the use of the word "SCIENCE". Pay attention. The Yooper
  18. Global warming and the unstoppable 1500 year cycle
    Re: daniel (22)
    "I'm sorry but this simply has not been shown. I have already refuted the idea in my comments in the relevant "Argument" # 21. (comments 7 & 8). It's time to wise up gentlemen. Climate science is not science."
     Dude, you're giving me a bad name. I've read your comments over at argument 21 (7&8). Merely asserting something could be wrong and alleging impropriety doesn't make it so. If you have something of substance that will stand peer review that supports your allegations - bring it on. Or better yet, publish it. I'm sure you'll find many "skeptical" organizations will be glad to provide you with technical copywriters to assist you as well as financial support for your time to do so. I also suggest you actually do a little research on the background of paleo temperature records. Here's just one place to start. There are many more. In the meantime, you're blurring the line between skepticism and denial. BTW, climate science IS science. Hence the use of the term "science". The Yooper
  19. Global warming and the unstoppable 1500 year cycle
    Not been shown? This is just the summary basic version. Perhaps we need to wait and see how the intermediate and advanced versions of this one pan out then.
  20. Climate Change: The 40 Year Delay Between Cause and Effect
    Thanks number 4 CB The time lag as you explained- the immediate effects also can be felt- theoretically- the warming we feel today be goes back to the late 70s or early 80s- 30-35 years ago when the CO2 level was 330-340ppm. Hansen and McKibben have put a maximum level of 'safe' CO2 at 350- but even that may be to high- but for all practical purposes 350ppmv is the goal we can only hope to reach.
  21. Climate Change: The 40 Year Delay Between Cause and Effect
    sleepership, the cause of the lag is explained in the article. Basically, just as when you put a pot of water on the stove it does not immediately begin releasing heat to the air above the water so also does the extra heat going into the oceans take time to make its way into the atmosphere. That said, yes there is also an immediate effect... some of the additional heat goes directly into the atmosphere. However, the surface of the Earth is 70% water. When you add in that this water is always moving and the vast VOLUME of the oceans it is obvious that the vast majority of the warming goes first into the oceans. thingadonta, 'for sake of brevity'? Gee, I'd think it wasn't mentioned because the high solar activity in question was ~80 years ago.
  22. Arkadiusz Semczyszak at 21:22 PM on 22 September 2010
    Does Climate Change Really Matter?
    “Big storms and extreme weather require a lot of energy to drive them.” Nothing could be further from the truth. Great storms require a considerable variation in energy over a small area. The violent weather phenomena occur in the specified temperature range. Hence warming - only if in a strictly defined temperature range - will increase the number of extreme events. The same cooling. This explains the theory of fluid mechanics. On the surface hydrophobic water droplets combine (and simultaneously disconnect) rapidly only in the specified temperature range. The increase in temperature causes the droplets merge is declining, growing up (more "lazy") drops consisting of several smaller drops. They join fewer and much milder. Also, if we treat the global atmospheric circulation as a cybernetic system, we understand that with the increase of the energy supply to such an system, he will be able to run additional feedbacks stabilizing system - number of extreme events as a result of warming MUST be reduced. Polish scientists (Natural Disasters, 2008.) write: "In the years 1701-1850, ie during the period when the Earth was in the so-called Little Ice Age in the Caribbean basin hurricanes were almost three times higher than in the second half of last century, and from 1851 to 1950 - twice as frequent. [!!!] Total number of tropical cyclones on Earth in the twentieth century, was twice smaller than in the nineteenth century [!!!]" In periods other former cooling (8-8,3; 5,1-5,7, 4.5 ≈ 2.1, and 2-1,6 thousand years ago) has always followed a significant increase in strength of ENSO - tropical cyclones ... In the United States during the beginning of Dalton minimum in 1780, the largest ever recorded in the so-called. "Great Hurricane" (much stronger than Hurricane Katrina) killed at least 22,000 people ... Currently, when the estuaries are much more densely populated ... Rising temperatures have already by 1.5 ° C will reduce the frequency of high-pressure system (anticyclones), the extension of the troposphere. Compared with the current temperatures, will reduce pressure gradient in the atmosphere, also lose their importance as barriers to the mountains. Beautifully seen an example of the Sahara. In the summer there are only shallow low-pressure systems, but only in winter powerful, stationary anticyclones (indeed, as in Siberia). Phenomena in the atmosphere does not occur linearly. Currently, Hadley cell expands. As a result of warming of 3-4 ° C, as always, extend, however, (on N and S) Ferrell cell. Hadley cell may even disappear - like cell zone separating the two areas of high pressure (the same way as - described above - in the summer in the Sahara). Heat waves in the NH (2003, 2006, 2010) are associated more with violent beginnings of La Nina - cooling of the oceans, fewer algal NPP - cloudiness (CLAW hypothesis). Global warming and United States landfalling hurricanes, Wang and Lee, 2008.: “Warmings over the tropical oceans compete with one another, with the tropical Pacific and Indian Oceans increasing wind shear and the tropical North Atlantic decreasing wind shear. Warmings in the tropical Pacific and Indian Oceans win the competition and produce increased wind shear which reduces US landfalling hurricanes.” The authors also say: “This paper uses observational data to demonstrate that the attribution of the recent increase in Atlantic hurricane activity to global warming is premature and that global warming may decrease the likelihood of hurricanes making landfall in the United States.” “The accumulated cyclone energy index, which has been used to measure tropical cyclone activity, is also observed to have a downward trend for global hurricanes over the past two decades when consistent satellite imagery has been available.” May vary regionally (IV IPCC report and „... the North Atlantic to warm more slowly than other oceans ...” - weakening of the AMOC - cooling of the North Atlantic) and the gradient of "vertical wind shear" may rise. However, declining globally (with warming) gradient of "vertical wind shear" decides to lower the intensity and frequency of all storms, not just the big.
  23. Climate Change: The 40 Year Delay Between Cause and Effect
    re#1.Perseus. Yes, there is no reason why the ~40 year ocean heat lag should only apply to greenhouse gases. It also applies to heat from the sun. Of course it isn't mentioned, for sake of 'brevity', or some such. The 'energy imbalance' referred to by the moderator and claimed to be increasing since the mid 20th century, as I understand it,has been modelled, not measured. And yes, you guessed it, modelled using greenhouse gas models. You can get a feel for their reasoning from the very first sentences in the following abstracts. 1. Earth's Energy Imbalance: Confirmation and Implications James Hansen,1,2* Larissa Nazarenko,1,2 Reto Ruedy,3 Makiko Sato,1,2 Josh Willis,4 Anthony Del Genio,1,5 Dorothy Koch,1,2 Andrew Lacis,1,5 Ken Lo,3 Surabi Menon,6 Tica Novakov,6 Judith Perlwitz,1,2 Gary Russell,1 Gavin A. Schmidt,1,2 Nicholas Tausnev3 "Our climate model, driven mainly by increasing human-made greenhouse gases and aerosols, among other forcings, calculates that Earth is now absorbing 0.85 ± 0.15 watts per square meter more energy from the Sun than it is emitting to space. This imbalance is confirmed by precise measurements of increasing ocean heat content over the past 10 years." http://www.sciencemag.org/cgi/content/abstract/308/5727/1431 2. "Using a climate model that incorporates anthropogenic greenhouse gas emissions, scientists have recently concluded that the Earth is absorbing more energy than it emits. The energy imbalance, when compared to temperature measurements, indicates a lag in atmospheric warming." http://www.wri.org/publication/content/7678 3. Roy Spencer has some alternative ideas. http://www.drroyspencer.com/2009/07/how-do-climate-models-work/
  24. Climate Change: The 40 Year Delay Between Cause and Effect
    Is this time lag an absolute? Co2 now at around 390ppmv will 'only Be felt' in temperatures around the year 2050 (with all the significant feedback's)Or does that 390ppmv today have any effect on us? Hansen has said that ice will melt and soften up in the arctic at 375-400ppmv- which is what is happening- Or does time lag mean the CO2 emitted today will be around 30 years from now? Anyone care to explain?
  25. Climate Change: The 40 Year Delay Between Cause and Effect
    Could this same 40 year lag in increased tempeatures be used as an 'explanation' by a sceptic for the Solar influence which peaked way back in the last century?
    Response: No, the way climate time lag works is when the planet is in energy imbalance (eg - more energy coming in than going out), the planet steadily accumulates heat and warms. As it warms, it radiates more heat out to space until eventually, the energy out equals the energy in and the planet is back in equilibrium. So the way climate time lag works is the planet gradually warms over decades and the energy imbalance gradually shrinks.

    That's not what we've seen over the last half century. After solar activity peaked in the mid-20th century, the planet's energy imbalance - rather than shrink - has actually increased as CO2 levels have increased.
  26. Global warming and the unstoppable 1500 year cycle
    From the article above: "The 1500-year cycle in question has been observed mainly through ice core data as a warming in the northern hemisphere matched at precisely the same time by a cooling in the southern hemisphere. So it’s a heat distribution issue: a global temperature ‘see-saw’ effect. The total heat in the global system remains constant." I'm sorry but this simply has not been shown. I have already refuted the idea in my comments in the relevant "Argument" # 21. (comments 7 & 8). It's time to wise up gentlemen. Climate science is not science.
  27. Does Climate Change Really Matter?
    Perhaps the following question might be more pertinent, "Does the dog wag the tail or the tail wag the dog?" Suppose that both are possible. Then the next question might be, "Could they ever occur simultaneously, and if they did, what would be the consequences?" "Scientists" believe that tail wagging indicates a state of conflict. People believe that happy dogs wag their tail, but many "happy dogs" have bitten people. This leads to the possibility that the tail may be wagging these "happy dogs," which makes them mad, so they bite you. Since a dog can't both be happy and mad at the same time, it is impossible that the dog is wagging the tail and the tail is wagging the dog at the same time. So there you have it. But what if a 2-3 °C rise in global temperature were to cause some weird change in a dog's disposition, such that it can be both happy and mad at the same time? Now the dog can wag the tail and the tail can wag the dog at the same time. That has never before been seen in nature, so no one knows what the outcome will be. Think what would happen to the poor dog if simultaneous dog wagging tail and tail wagging dog were to cause a "Positive Feedback." Now I don't believe in God, so I tend to think that man was not created in His image and can therefore become extinct, just as easily as any other "animal." Unless man can devise a way to live happily ever after with giant clouds of methane burbling up from the ground and oceans, he ought to be taking more seriously prospects of the "Day of Judgement."
  28. actually thoughtful at 17:22 PM on 22 September 2010
    A detailed look at Hansen's 1988 projections
    There is a very interesting phenomena at work here - not just restricted to the deniers. Hansen's 1988 graphs show 3 lines, based on 3 sets of inputs. We all (except for Michaels - but it is 2010 - I personally have no time for those that deny the world is warming)... so we easily rule out scenario "A" - neither the emissions nor the temperatures line up - so out the window it goes. Dana1981 presents the information, with technical support. I think I am accurately paraphrasing Dana1981 to say: Only scenario B is worth looking at - because that is a pretty close match to actual emissions. Scenarios A and C are provided for completeness and context, but are not germane to the discussion." Many readers (and I include myself) need at least an acknowledgement that actual temperatures are at/near/below Scenario C (or to have our noses dragged through the point that "C" doesn't matter BECAUSE the actual emissions don't match that Scenario). I know realize that the whole point is to compare Scenario B temperatures to reality, because Scenario B matches the emissions - but my first reading I was wondering why Scenario "C" - which looks like a good match (based on temperature), is irrelevant. I think this is the difference between rigorous scientific thinking, and interested bystander thinking. Anyways, it is one reason why I like this blog - thank you for making that point clear to me! Regarding my post 67 comes up with 19% because I choose 4.2 for the denominator. I think that is valid because it is Hansen's error divided by Hansen's choice - rather than Hansen's error divided by reality - mine is internally consistent. But I grant that it is pretty much semantics at this point. Finally - for anyone to look at this and be anything but amazed that someone, in 1988 - when all the theories of climate that EVENTUALLY became AGW were still in the "maybe" column and not be amazed at how prescient and accurate Hansen was, just befuddles me!
  29. Does Climate Change Really Matter?
    A good article. It is kind of curious to note, however, that for those of us who do not know RFR FM is an Australian station, the only clue that the text was written for Australians is the .au suffix in the URL (there are other cities named 'Perth' -- such as in Scotland). This is relevant, since there are other points in the article that are much clearer once you realize it was written for an Australian audience. The use of unadorned numbers for temperatures in degrees Celsius is a prominent example. Remember you WANT more Yanks reading your articles! But for us, 'degrees' measuring temperature as assumed Fahrenheit unless we are told otherwise. 2-3 degrees Fahrenheit really is small. But we can easily see 2-3 degrees Celsius as much more significant. I suggest the site deal with this problem by the use of the common convention of putting explanatory text, text not in the original transcript (since this was broadcast over the radio) in square brackets. So, for example, "rise 2 to 3 degrees" becomes, "rise 2 to 3 degrees Celsius". Likewise, 'Perth" becomes, "Perth, Australia".
  30. Does Climate Change Really Matter?
    cruzn246 - "Record High Temperatures Far Outpace Record Lows Across U.S.". And this is up to 2009 - 2010 is even warmer. http://www.ucar.edu/news/releases/2009/maxmin.jsp#
  31. Anne van der Bom at 16:02 PM on 22 September 2010
    A detailed look at Hansen's 1988 projections
    I must have got this seriously wrong. AFAIK climate sensitivity is an outcome of the climate models, not an input.
  32. Does Climate Change Really Matter?
    A suddenly appearing, prolonged 2-3 degrees rise of the ambient temperature in humans leads to a situation where the individual in question normally goes to a doctor.
  33. Does Climate Change Really Matter?
    Is there a rss feed for the climatecast?
    Response: RTR FM have a podcast page but not specifically for the fortnightly climate podcast. If people are interested, I could ask the UWA folk whether it would be possible to host their audio recordings on Skeptical Science.
  34. The contradictory nature of global warming skepticism
    Re: Composer99 (328) While I don't speak for John Cook's or any of the regular authors here, I'm sure that they welcome the feedback. If there's anything unclear in your mind on any of the posts or if there's a topic left unaddressed or that you'd like to suggest a post on, please do speak up. Contrarians tend to run into many pitfalls, perhaps the deepest of which is the Dunning-Kruger Effect, to which extremely knowledgable and highly trained people can fall victim to. Others are Cognitive Bias and issues with Critical Thinking. The Yooper
  35. Climate scientists respond to Monckton's misinformation
    I already had Douglas looked up ;-) Sorry to be OT, but it seemed important in context with the new article at Pielkes Sr. blog.
  36. Does Climate Change Really Matter?
    #1 cruzn246 This is a science site. Please present compelling evidence when you make claims, so that we'll know why we should listen to you instead of, say, Thomas Karl, or the World Meteorological Association.
  37. Climate scientists respond to Monckton's misinformation
    Oslo @24, Thanks for the heads up. This is OT of course, but let us not forget the dismal Douglass et al. (2007)--which was co-authored with Singer-- before we give their findings too much weight. I have infinitely more faith in the UofW research that you linked to. That "missing" heat, it appears, is working its way down much deeper than thought-- quelle surprise.
  38. Does Climate Change Really Matter?
    There is no upswing in extreme weather.
  39. Climate scientists respond to Monckton's misinformation
    New important study announced (NOAA): Scientists Find 20 Years of Deep Water Warming Leading to Sea Level Rise It should debunk Pielke Sr. new spin on the matter: New Paper “Recent Energy Balance Of Earth” By Knox and Douglas 2010 Oh, and it might prove the new Antarctic / Greenland ice loss study correct?
  40. actually thoughtful at 12:21 PM on 22 September 2010
    A detailed look at Hansen's 1988 projections
    NETDR @48 4.2-3.4=.8 /4.2 = 0.19=19% = that is how much Hansen is off from reality. You keep coming up with 44% by "eyeballing" .9 where .9 does not exist. What is the point of discussing if you don't keep your posts based in reality?
  41. The contradictory nature of global warming skepticism
    Like Baz, I am also an outsider to the sciences (my last exposure to it being in undergrad courses some years ago before I switched majors). Unlike Baz, however, I am not prepared to suggest that an outsider with no special training or expertise on a subject is capable of overturning a body of evidence assembled by hundreds of people with both qualities on the basis of a single, statistically-insignificant trendline. I certainly will not dispute that skepticism of any claim made in respect to AGW is required. I would, however, think that claims that run against the grain (so to speak) are to be scrutinized as closely as claims that are in favour of the current scientific consensus. Also, on topic for this thread, the tendency for contrarian websites to espouse mutually-contradictory arguments simultaneously is surely a blow to their credibility as sources of rational discourse and/or reasonable criticism of the way in which climate science is conducted. Personally speaking, after reviewing the excellent summaries of the science on this site, as someone with little formal training or understanding of the subject I feel like I know a lot more about how climate science works and how it has come to the conclusions it has regarding anthropogenic climate effects.
  42. A detailed look at Hansen's 1988 projections
    Dana @64. Mea culpa Dana. Sorry. I really need to stop multi-tasking. As you noted, you state in the post: "So we'll assume that the global surface air temperature trend since 1984 has been one of 0.20°C per decade warming."
  43. A detailed look at Hansen's 1988 projections
    @NETDR: "Using 5 year averages to avoid cherry picking." To avoid cherry picking, use the linear trends for both Scenario B and the temp record. Using averages but arbitrarily choosing dates is still cherry-picking.
  44. A detailed look at Hansen's 1988 projections
    NETDR - if you don't know where I'm getting 77% then you've read neither the article nor my comments (or can't divide 0.20 by 0.26, as Albatross illustrates). I have no idea where you're getting yours from - cherrypicking favorable data points no doubt. Albatross - I explain in the article why I use 0.20. It's the 'surface air temperature' issue and how that's defined. But using 75% is fine, I like rounding. I guess my problem here is that I'm expecting readers and commenters at Skeptical Science to think like skeptical scientists. A skeptical scientist does not say "Hansen was wrong and I don't care why." That's incredibly unscientific. It's critical to know what is responsible for scientific inaccuracies. For example, why was the UAH satellite temperature data so radically different from surface station data a decade ago? Were the satellites wrong? Were the surface stations wrong? Was somebody fudging the numbers or screwing up the analysis? No scientist would simply say "oh well the temperature data is just wrong and I don't care why." I think the problem here is clearly that "Hansen was wrong" is a much more convenient conclusion for certain biased individuals than "Hansen's results are evidence that the IPCC and today's climate models have the climate sensitivity right".
  45. A detailed look at Hansen's 1988 projections
    Swinging back to the original point of this article, its about misrepresentation. Claiming the temperature results from high emission scenario were Hansen's prediction and comparing that curve to actual temperatures which are actually more relevant to a different scenario is out and out dishonest. Redtrawing the graph so that those "confusing" other curves which would give a clearer picture shows this was a deliberate attempt to mislead. Hansen on the other hand is giving the results for the best climate model available at the time. He didnt CHOOSE a sensitivity of 4.2 - this is an output from the model. Are we surprised that model got it wrong considering how primitive it was? No, and we now understand why it was wrong too. We still struggle to get an accurate number for short-term (10-30 year) climate sensitivity. An imperfect model is not dishonesty.
  46. Climate scientists respond to Monckton's misinformation
    Rob Honeycutt @ 15 ….”Expect a number of Fox News interviews to follow shortly” Well, maybe. My guess is that while the Murdoch media is willing to give Monckton a free pulpit from which to spew his nonsense, the wily and mischievous Murdoch will not publicly support Monckton’s views. Murdoch knows, as we all should by now, that anything Monckton says on global warming, climate change or its other effects, is wrong. My only quibble with Monckton’s critics is that they accuse him of misunderstanding science. He does not misunderstand, he deliberately and knowingly misrepresents.
  47. A detailed look at Hansen's 1988 projections
    NETDR @60, "Where you got the 77 % I will probably never know." Try this: 0.20/0.26 = .... Actually, I disagree slightly with Dana and suggest that for 1984-2009, 73% of the predicted warming was realised (0.19/0.26). But there are those error bars in the observed and predicted warming, so I should not nit pick at differences of 0.01 C when the error bars are 0.05 ;) How about, approximately 75% of the predicted warming between 1984 and 2009 was realised.
  48. A detailed look at Hansen's 1988 projections
    @NETDR: So, just to be clear, you *don't* agree with Michaels when he says "the forecast made in 1988 was an astounding failure." I'm just trying to establish your position here. It's kind of tricky with deniers (which you clearly are, by your approach and choice of rhetoric). "Reading the graph of Dr Hansen's predicted warming and the climates refusal to co-operate with him doesn't take a PhD." Actually - and this is the whole point of the article - the climate "sort of" cooperated with his assessment, i.e that temperatures were going to go up by a significant amount. He overestimated the final result, but got it mostly right compared to, say, someone who would have argued it was going to be cooling, or that temperatures were going to stay the same. Your absolutism fools no one, you know... "My having a particular belief of climate sensitivity or use this article. is a false choice." Of course not. It's simple logic: either you think the argument is scientifically valid, or you don't. You just want to cherry-pick the parts you like, and ignore the parts you don't. Typical. "You spin fallacy after fallacy," I certainly do not. You, on the other hand, are clearly trying to push an agenda. "Far from being Boolean a model which predicts so much warming that only 44 % of it occurs is broken." Not 44%. The error was 0.8 on 3.4, so about 1/4. Hansen got it about 75% right. But keep on ignoring the arguments presented to you, and restating the same faulty calculation. You're really gonna go far with that one.
  49. Climate scientists respond to Monckton's misinformation
    Re #21, Thanks Scott. Good points-- people need to be proactive. Those letters are not ignored and I have been told that, in my country at least, letters carry a lot of wait, especially nowadays.
  50. Climate scientists respond to Monckton's misinformation
    To my fellow Americans: Write to your elected officials and ask them to investigate Monckton and to consider if they believe he committed perjury. You can locate your Reps and Senators at USA.gov After doing that, consider writing to the top medial outlets. I have a lengthy list here. Do not be content to just applaud on a blog.

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