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Comments 110201 to 110250:

  1. How we know the sun isn't causing global warming
    Riccardo #48,49 Do you have a different number of W/sq.m for incoming solar than 239-240? Pray tell us what it is?
  2. European reanalysis of temperature confirms record warmth in 2010
    I dont want to be pedantic but focussing on the extratropical northern hemisphere largely increase the global warming signal compare to a true world average temperature.
  3. The contradictory nature of global warming skepticism
    Hello JMurphy. Happy to answer your questions (even though you and others haven't answered mine): "How can "that blue line" (that has been trending upwards since 1850) have turned you into a so-called skeptic and ex-member of Greenpeace ?" Because when warming didn't continue at the same pace (around 2005) I began to question if I was right about my beliefe in warming. "How could you have been a "believer in warming" rather than an accepter of the facts ? Why do you deny the facts now ?" That's a problem if mis-reading you have there which seems to have affected a number of people here. Is it common? As I have said on here, I don't deny the facts - the physics of GHGs, but what I do deny is that we 'know' what the overall result will be (pos/neg feedbacks). "How can you be sceptical of warming temperatures when the graph you give a link to shows warming temperatures since 1850 ?" AGAIN(!) I'm not sceptical of warming thus far. I'm sceptical that warming will continue - that there will be a postive feedback from contuing with our release of CO2 etc. "What ("a few years back") was so damning in your eyes ? Can you give the details ? What was the trend, and over how long a period ?" As I said, I re-looked at the issue around 2005. Up until around then I was a believer. I'm not fully in the sceptic camp apparently, but have pitched a tent outside. The HadCRUt global series shows remarkable stability over the past 10 years despite an ever-increasing CO2 release. So five years ago I questioned if my belief was correct. My question (again) to you and others is when will you question your belief: 10 years? 20 years? Only 'VeryTallGuy' has answered!
  4. European reanalysis of temperature confirms record warmth in 2010
    Where are the plots for global heat content anomaly and global dew point anomaly?
  5. A history of satellite measurements of global warming
    wingding #7, I disagree that criticisms of Spencer and Christy as scientists are baseless. I had linked to articles quoting them making what I consider blatantly unscientific / biased / false statements as evidence of this, but it was apparently deleted. Which seems somewhat overzealous to me. It was certainly no less polite than, for instance, comparing people who denounce Spencer and Christy to the "behavior seen at WUWT".
  6. The contradictory nature of global warming skepticism
    VeryTallGuy, many thanks for that, it's much sppreciated. So for you, it would be 20 years, that's fair enough. kdkd. No, it's not any approach at misdirection at all, it was simply a question! VeryTallGuy answers it, why not give it a try yourself? I wasn't actually referring to any previous bumps, as that would be prior to Tamino's 1975 start. But I wasn't referring to bumps at all, but prolonged stability or decline.
  7. The contradictory nature of global warming skepticism
    Baz, in addition to all the other answers pointing out the statistical fallacy of your argument it also requires acceptance of something we already know to be false... "Just suppose, for a minute, that this blue line carries on reasonably straight, or even heads down" Why would I do that... when we've already got eight months worth of data for 2010 showing it to be thus far the hottest year ever recorded? Your 'just suppose' scenario has already been contradicted by the actual facts. That said, the question, 'how long would it have to be flat or negative to disprove man made global warming', is inherently flawed. If you look at it at all logically you should be able to see that the duration of fluctuations depends on what causes them. That chart shows temperatures dropping from ~1880 to 1910... so obviously 30 years of declining temperatures didn't 'disprove man made warming'. If we started releasing all the particulate pollution we could and blotted out the Sun for 50 years the cooling from that wouldn't 'disprove man made warming' either. BTW, you should also work on your phrasing. The idea of 'disproving AGW' is ridiculous. AGW is an observed fact. In some of your posts you have specified that you question the extent of positive feedbacks. That is not wholly unfounded, but describing it as 'disproving mad made warming' is just nonsense. Extensive research has narrowed current 'climate sensitivity' to a range between roughly doubling warming from a forcing (in this case human CO2 emissions) to multiplying it by as much as a factor of five (with higher values considered very unlikely, but not completely ruled out). To 'disprove' that with a lower climate sensitivity you'd have to show some climate process which all that prior research overlooked or miscalculated. In the mean time, ponder this... climate science says a doubling of CO2 from the historical ~280 ppm to 560 ppm would produce about 1 C of warming and that feedbacks would increase this to at least 2 C or more (best estimate is currently about 3 C). We are presently at about 390 ppm... a 40% increase. Yet we have already seen over 0.8 C of warming. We're at nearly 1 C warming with less than half the CO2 increase needed (by itself) to get us to that point. How does that NOT indicate that net feedbacks are positive and significant? Especially since it is right in line with the projections of 3 C for doubling of CO2?
  8. Arkadiusz Semczyszak at 21:38 PM on 13 September 2010
    The Little Ice Age: Skeptics skating on thin ice
    ”Volcanic activity was high during this period of history ...” However, it appears that the high volcanic activity may be warming rather than cool. Sulphur aerosols act (higher albedo), a relatively short time - causing the cooling. Volcanoes “stratospheric” would erupt every year - as was the case during the Triassic. Volcanoes as an ozone-destructive - act in a very long period of time. Example: LIA - Tambora eruption in 1815 - "year without summer" in Europe - but the years 1818-3? was warmer or much warmer than before the eruption of the volcano. Ozone - the thinner the layer - the higher the mortality of marine phytoplankton. Phytoplankton and Cloudiness in the Southern Ocean: “The effect of ocean biological productivity on marine clouds is explored over a large phytoplankton bloom in the Southern Ocean (SO) using remotely sensed data. Cloud droplet number concentration over the bloom was twice what it was away from the bloom, and cloud effective radius was reduced by 30%. The resulting change in the shortwave radiative flux at the top-of-the-atmosphere was -15W m-2 ... ” Positive feedback - the more ULV = the less phytoplankton = the lower the cloud cover = more ULV ...
  9. European reanalysis of temperature confirms record warmth in 2010
    Re: Johngee (9) Figure 1 is for land areas north of 20 degrees north for May-June only. Figure 2 is for combined global land + sea areas. Both use a baseline of 1989-2001 and use anomalies instead of temperatures to reduce weather-related noise in the data. Both are surface-layer (2-meter) data instead of something like satellite-obtained data, which can also measure various layers of the atmosphere (the Earth's atmosphere is layered like an onion; because of this, it heats and cools differentially. The addition of CO2 essentially causes a differential accumulation of heat in the lower layers by slowing the transfer of heat to upper layers. Hence stratospheric cooling and tropospheric heating). Figure 1 shows that, in the 40 years of data shown, land temps away from the tropics have warmed in the last 10 years relative to the other 30 years of data. Figure 2 shows that global (land + sea) temps have been rising fairly linearly across the entire range of the data (if you were to put a ruler on the graph and draw a straight line through the midpoint of each year of the data, you'd get a line rising from the left side of the figure to the right side. This line is said to have a positive slope, showing the upward overall "trend" of temperatures in the data). Both figures show an essentially noisy dataset (even using anomalies to reduce the noise), but one in which a clear signal can be seen. It's getting hotter. And there is no indication of slowing in the rise of temperatures. Hope that's more clear! If you have more questions, let me know. The Yooper
  10. Arkadiusz Semczyszak at 20:09 PM on 13 September 2010
    The contradictory nature of global warming skepticism
    I have only one question: Is it because Anthony Watts has published two posts (05 and 20.082010 - WUWT) by Ferdinad Engelbeen (He is "hot advocate” of the theory AGW - - Why the CO2 increase is man made (part 1) and part 2) - Anthony Watts publishing these posts has been "a follower” of the theory of AGW?
  11. A detailed look at climate sensitivity
    BP #46 I am trying to understand what's going on. Sorry but the evidence suggests that this is not the case. If it was, you would have dealt with the serious deficiency in a prior analysis or allowed someone else to do so. Fixing this problem is simple (I can do it for you if you don't know how to do it yourself), yet despite repeated requests you have not done so. I suggest you fix the problem so that you are not continually nagged about it, as it reflects very badly on your credibility at present
  12. European reanalysis of temperature confirms record warmth in 2010
    Last (NH) winter was the warmest on record (average global temp)
  13. The contradictory nature of global warming skepticism
    Baz #98 I think that's a fascinating question because it clearly illustrates the Real hockey-stick illusion. Not the McIntyre/Mann "debate"; but the focus on Temperature alone produces an illusion in itself. What is happening, in fact, is AG-Energizing. Energy is being pumped in faster than it is escaping. Energy goes to a number of places: it can warm up air, melt ice, warm up water, vaporise water, generate strong winds and waves. Schematically: Air has twice the specific heat capacity of Ice which is twice that of water: and the latent heat of water is almost 100 times its heat capacity... So, consider a system with for equal weights of water/air/ice close to equilibrium into which energy is pumped. An increase of 1° in air temperature represents a fraction of the total energy absorbed by the system. Of course there are details, e.g. is the ice just below 0° or is the core -20°? Water cannot always vaporise, that depends on partial pressures. If there's significant humidity, for example, than the air temperature rise will be different for the same increase in total input energy (i.e. it depends on the initial temperature). Of course the world has vastly different amounts of air, ice and water, they are nowhere near in equilibrium - so that some energy goes into dynamics caused by disequilibrium (waves, wind etc.). It may be hard to work out exactly where all the energy might go and in what proportions... but, empirically, if more energy is going into the system, one would expect all these system to respond in a generally obvious way; maybe a little more melting here, a little less there - but more snowfall... But, for me, the killer argument for AGW (really AGE) is that everywhere we look there's, generally, more energy.
  14. The contradictory nature of global warming skepticism
    archiesteel (#96), in laymen forums I always ask the same question: what is the catastrophe? I pointed out the hunting of polar bears here on the polar bear thread and got no answer. I asked here what temperature was required in the model that melted Greenland's ice in a few hundred years, again no answer. Then in many of the rainfall = catastrophe threads I point out that the sensitivity is directly lowered as water vapor becomes more uneven. So far I can safely say there is no catastrophe, not now and not for a long time, so speculating on high sensitivity without support is not prudent or cautious, but rather reckless. All that said (much too abbreviated to be convincing), a substantial change to the earth like CO2 increases should not done without any consideration of possible negative outcomes. I want to see more science in that area and less hype (e.g. my first quote in this thread, as well as research on positive outcomes.
  15. The contradictory nature of global warming skepticism
    Baz wrote : "As I've said, I'm sceptical that what we're doing (our experiment with the atmosphere) will result in warming temperatures - and I'll tell you why. It's that blue line. Oh yes, I used to be a believer in warming. Hell, I used to be a member of Greenpeace. But just a few years back I couldn't equate that with that blue line. Admittedly, I came off the warming horse early, but what of some of you? For how long does that blue line have to go straight or fall, for you to question the very subject this site is based on?" How can "that blue line" (that has been trending upwards since 1850) have turned you into a so-called skeptic and ex-member of Greenpeace ? How could you have been a "believer in warming" rather than an accepter of the facts ? Why do you deny the facts now ? How can you be sceptical of warming temperatures when the graph you give a link to shows warming temperatures since 1850 ? What ("a few years back") was so damning in your eyes ? Can you give the details ? What was the trend, and over how long a period ?
  16. Arkadiusz Semczyszak at 19:14 PM on 13 September 2010
    Industrial CO2: Relentless warming taskmaster
    “The central issue is TIME.” “... so we'll SUDDENLY kick CC into overdrive.” - Full consent 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.” Here we quantify the median c as 7.7 p.p.m.v. CO2 per 6C warming, with a likely range of 1.7–21.4 p.p.m.v. CO2 per 6C. “, “Our results are incompatibly lower (P,0.05) than recent pre-industrial empirical estimates of 40 p.p.m.v. CO2 per 6C (refs 6, 7), and correspondingly suggest 80%LESS [!!!] POTENTIAL AMPLIFICATION OF ONGOING GLOBAL WARMING.” So we have more time than we have - not so long ago - it seemed ... “We will need to invest in carbon capture technologies.” Absolutely not! It is extremely costly and will earn in that only Exxon and other fuels consortium . We need to invest in renewable energy ONLY.
  17. European reanalysis of temperature confirms record warmth in 2010
    cruzn24, As you can see from the above graph, the temperatures never were below the average from 1989-2001. The recent cold was localized in area and not that cold. Most of the world was hot last Dec-Jan-Feb while the cold areas were genreally the USA and parts of northern Europe. It is a denier fantasy that it was cold last winter. The data does not support that fantasy.
  18. A detailed look at climate sensitivity
    #45 scaddenp at 09:08 AM on 13 September, 2010 So are you really looking to understand limits and skill of models, or looking for excuses to dismiss them as fits another agenda? I am trying to understand what's going on. Have a look at this review article, please. Phil. Trans. R. Soc. A (2005) 363, 2931–2946 doi:10.1098/rsta.2005.1676 Published online 24 October 2005 Modelling climate change: the role of unresolved processes BY PAUL D. WILLIAMS "In climate models, too, it is tacitly assumed that the effectively random subgrid-scale events are so large in number that their integrated effect on the resolved scales is predictable, allowing it to be included in models. However, in fluids there is an enormous separation of scales between the microscale and the macroscale. There is no such ‘thermodynamic limit’ in the climate system, as suggested by figure 1. Phrased differently, if there were a billion clouds, gravity waves or ocean eddies in a GCM grid box then their impacts on the resolved flow would be predictable, like the temperature of a gas, and the current treatment of unresolved scales in climate models would be defensible. But such a separation of scales between the resolved and unresolved dynamics simply does not exist. The number of sub-grid-scale events per grid box is not large enough to permit the existence of a meaningful statistical equilibrium." But simply adding random noise to climate variables as the author insists is not a panacea either. As the climate system is not an ergodic process, it is a bit difficult to collect reliable empirical data on statistics of the noise to be added, although as we have seen above, in some cases the statistics alone can determine the outcome. These are all pretty fascinating stuff, I just wonder why this side of the coin is left out from climate communication entirely including research press releases and this fine science blog itself.
  19. The contradictory nature of global warming skepticism
    Baz, I suggested a way for you to do this analysis up the thread #38. As you've obviously not done that, here's the results. According this method, with heating on a trend of 0.2 degrees per decade and noise with a standard deviation of 0.2 degrees on the annual data, you can expect: 1) 18% of decades will have a negative slope 2) 5% of 15 year time slices will have a negative slope 3) 0.2% of 20 year timeslices will have a negative slope So, a decreasing trend over ten years is reasonably likely and can be expected. A decreasing trend over 15 years can be expected one year in twenty. A decreasing trend over twenty years is very unlikely and would, for me, falisfy AGW unless there are known reasons for the decline eg major vulcanism. Why not repeat this simple analysis yourself? You'd find it far more convincing than reading blogs.
  20. European reanalysis of temperature confirms record warmth in 2010
    Johngee - It's a plot of the difference between the calculated global average and an average of those temperatures recorded from 1989 to 2001 (if you look at the 'area under the graph' for that period it will average out at 0.0 anomaly). It's showing how the calculated global temperature has changed with respect to that period. The period chosen is arbitrary, though it helps to use the same comparison period as everyone else to make comparisons easier.
  21. The contradictory nature of global warming skepticism
    Baz #98 There's nothing a priori which distinguishes the terminal bump in that graph from the 4 other bumps since 1950. Claiming otherwise is wishful thinking, not based on any logically derived scientific or mathematical theory. I wonder what the effect the recent solar minimum which corresponds to the terminal would have had if it weren't for the counterbalancing effect of industrial CO2 emissions? Nice try, but it looks to me like your post is the standard so-called sceptic approach of misdirection, and failure to consider all of the available evidence.
  22. A history of satellite measurements of global warming
    Further to the acronym comment, can we have the expansion of MSU please. It's really hard to cover the enormous range of knowledge and background that comments to this and other climate change sites reveal. Thanks very much to all who are working at it.
  23. The contradictory nature of global warming skepticism
    Perhaps I can re-hash the point. What if this blue line http://hadobs.metoffice.com/hadcrut3/diagnostics/global/nh+sh/ doesn't continue upward? Just suppose, for a minute, that this blue line carries on reasonably straight, or even heads down - just suppose. For how long would it have to go straight (or down) for man-made warming to be falsified? As I've said, I'm sceptical that what we're doing (our experiment with the atmosphere) will result in warming temperatures - and I'll tell you why. It's that blue line. Oh yes, I used to be a believer in warming. Hell, I used to be a member of Greenpeace. But just a few years back I couldn't equate that with that blue line. Admittedly, I came off the warming horse early, but what of some of you? For how long does that blue line have to go straight or fall, for you to question the very subject this site is based on?
  24. Pielke Sr and scientific equivocation: don't beat around the bush, Roger
    Dr Pielke Any chance of a response to #159 ? thanks VTG
  25. Climate change: Water vapor makes for a wet argument
    KR, I see I did make a mistake in one post by mixing up higher and lower when referring to the relative temperatures, terrestrial and soil. My apologies. However it would have been obvious it was a simple mistake by reading the table referred to where the differences are obvious, and my other posts where I had referred to the differences correctly.
  26. Climate change: Water vapor makes for a wet argument
    Correction, you are getting me confused now. It is the SOIL temperatures which are ALWAYS HIGHER than the MINIMUM air or terrestrial temperatures, anyway this is clear from the BOM tables irrespective of what I might have written. The terrestrial minimum temperature is always lower than the minimum air temperature, which I believe is what I asked you originally to explain as to why this is so if back radiation warms the surface.
  27. Climate change: Water vapor makes for a wet argument
    KR at 14:18 PM, I trying very hard not to break into uncontrollable laughter, you are making it very hard not to. I have made it abundantly clear that the terrestrial temperature is measured at ground level, as does the BOM notes. I also pointed out that it is always lower than the air temperature which is measured 1.2m above ground level, and always higher than the soil temperature, which obviously is the temperature IN the soil, so I cannot understand what you are confused about as I have well made the distinction. Go back and read the relevant posts again, carefully. With regards to the minimum temperatures, whilst the readings are taken at 0900hrs, all this does is mark the end and beginning of each day. The minimum temperatures whether air or terrestrial will have occurred at some point within the preceding 24 hours, most likely during the night, not long before sunrise, in both cases each will be at the coldest point of the night. I repeat, the ground temperature is not the soil temperature, it is the AIR temperature taken AT ground level, not in the ground. In the ground measurements are identified as soil temperatures. What we call surface temperature as recorded by weather stations is the temperature at a standard height 1.2m above ground level, and if you don't know there generally is considerable variation in air temperatures in the first few metres above ground level.
  28. European reanalysis of temperature confirms record warmth in 2010
    I'm struggling with anomaly graphs in the above formats. I undestand the ones that NOAA produce - the one with the world map covered in blue and red dots. Could someone walk me through the above if if you were talking to a child please!!
  29. Arkadiusz Semczyszak at 16:19 PM on 13 September 2010
    European reanalysis of temperature confirms record warmth in 2010
    “or at least combine with hadley...” - if You please ... ... with ‘Global and European temperature (CSI 012) - Assessment published Jun 2010’ Here it looks a little "interesting", right? Especially before the year 1970 ...
  30. European reanalysis of temperature confirms record warmth in 2010
    cruzn246 - its an anomaly plot. The temperatures are shown wrt to average for 1989-2001. This is an arbitrary level, not "normal". If temperatures are trending up, then anomaly plots based on average of mid-temp will show left down and right up. Its "averaging out", it is trending up.
  31. European reanalysis of temperature confirms record warmth in 2010
    These temps are almost as far above normal as they were below normal not that long ago. I guess they are just averaging things out.
  32. Climate change: Water vapor makes for a wet argument
    Note to johnd - according to the chart you pointed to, the 'Terr min' is the temperature at ground level, not the ground (soil) temperature.
  33. Climate change: Water vapor makes for a wet argument
    johnd - to quote you: "...the "Terr min", Terrestrial minimum temperature, being the lowest overnight temperature measured at ground level, is always lower, often considerably lower than the minimum air temperature, whilst always considerably higher than the soil temperature immediately below the surface. Can you explain how back radiation allows this to occur in light of your explanation." However, the table you point to, the BOM data, clearly indicates that the 'minimum air temperature' and the 'Terr min' are measured at different times - at 9AM and at the coldest portion of the night. They are not comparable, although you seem to indicate they are - at least, that's how the question read to me. The ground temps will not cycle as fast as air temps, so I fail to see any issues with this data in regards to the physics of back radiation.
  34. European reanalysis of temperature confirms record warmth in 2010
    Wow, record warmth? This is just the warmest lately.
  35. European reanalysis of temperature confirms record warmth in 2010
    Another note for John, We should consider revising the 1998 is the warmest on record in light of this new result...
  36. European reanalysis of temperature confirms record warmth in 2010
    This will be a great resource. I wish they would do this every year... or at least combine with hadley...
  37. The contradictory nature of global warming skepticism
    Great post. The "skeptics" are trying to demolish the edifice of AGW, and will chip away wherever they can. An army of eager beavers hacking away at granite with toothpicks, slapping each other on the back and cheering when any piece of dust is dislodged. Don Quixote had nothing on them. Their endeavour and bravery are to be admired!
  38. The contradictory nature of global warming skepticism
    @Eric "Sensitivity is the largest area of uncertainty" Be that as it may, the degree of uncertainty with regards to CO2 sensitivity is relatively small. Considering the potentially catastrophic effects of AGW, and how politically-motivated contrarians use uncertainty as a tool to delay any action to mitigate it, I wonder what point is served by focusing so much on uncertainty values.
  39. European reanalysis of temperature confirms record warmth in 2010
    I'd just come here from a skeptics site, and was trying to make sense of the title, "European reanalysis confirm record warmth". For a second there I thought it was going to be an article about how warm the Medieval Warm Period really was!
    Response: Once I'd finished the article, I tweeted it and thought, well, that title doesn't make much sense, so I fleshed out the tweet with "European reanalysis of global temperature confirms record warmth in 2010". Thought about retitling my blog post with a more clear headline, decided against it mainly due to laziness. Will do the job properly now...
  40. European reanalysis of temperature confirms record warmth in 2010
    John, you left all the meaty bits out of the press release. "Temperature anomalies vary from one year to the next because of the natural dynamical variability of the climate system" "The global anomaly declines slightly in the very latest 12-month average, due to a recent shift toward La Nina conditions in the tropical Pacific and relatively low temperatures over tropical and southern hemispheric land areas, which offset last month’s high northern hemispheric temperatures."
    Response: I would've thought the year-to-year variability was pretty obvious from Figure 2 :-)
  41. The contradictory nature of global warming skepticism
    barry@55 said, CoalGeologist, for what it's worth, Watts has been promising for a couple of years now to submit a paper that re-examines the temperature record based on the surfascestations project. Hitherto, his publications (not peer-reviewed) have pointed out the problems but not crunched the numbers. Apparently, the paper is soon to be submitted. But you're right that he has made all sorts of pronouncements without doing a proper, comprehensive analysis, or even a half-arsed one. I think surfacestations.org is a good project, minus the rhetoric, and hope that his paper gets published. IMO, Barry is being a bit too kind to Watts and Co. If Watts and Co. were serious, they would have been crunching numbers from the get-go, adding data from each new surface temperature station as as soon as it was surveyed. There is simply no good reason to procrastinate on the data crunching until their "survey" is entirely complete. The temperature gridding/averaging process is not all that difficult conceptually -- basically it's a tedious programming slog. It's a straightforward task that any reasonably talented science/compsci/engineering undergraduate student could tackle. The surfacestations project was established over 3 years ago. It is quite telling that after over 3 years, the surfacestations folks still have not completed a straightforward number crunching task that a smart college student could easily do in, say, three weeks!
  42. Industrial CO2: Relentless warming taskmaster
    The central issue is TIME. Human activity is responsible for emitting CO2 in decades at a rate which would “naturally” occur over tens of thousands of years, speeding up consequential effects, most significantly rising temperature. Rapidly rising temperature amplifies the effect of CO2 emissions by thawing land which releases greenhouse gases, by melting sea ice which reduces albedo by warming and acidifying seawater and by increasing the speed with which glaciers and ice sheets melt. The prognosis is that air and sea temperatures will continue to rise as will sea levels and both will do so with increasing rapidity. The effects are likely to be an increase in the incidence and severity of climate events, loss of fresh water provided by stable glaciers and the erosion and flooding of coastal land. The effects on the human population, I leave to your imagination.
  43. A history of satellite measurements of global warming
    @ Dan Satterfield One the first rules of writing articles about technical subjects for the general public is to define all acronyms the first time they are used. For example, insert "(UAH)" immediately after the words, University of Alabama at Huntsville" in the first sentence. Also, the graph is also meaningless unless the reader knows what "RSS" and "UAH" mean. Insert the definitions into the graph. Some readers will only look at the graph and not read the text.
  44. The contradictory nature of global warming skepticism
    archiesteel (#89), sensitivity is the largest area of uncertainty, not the smallest. Temperature accelerates and decelerates in time scales of multiple years, decades and centuries. To assume a constant sensitivity and assign a linear temperature increase to a linear CO2 increase is difficult at any of those time scales although decade averages (2000's > 1990's > 1980's) works at the moment (http://www.drroyspencer.com/wp-content/uploads/UAH_LT_1979_thru_Aug_101.gif) muoncounter (#90) I have seen proxies for meridional versus zonal jet, so it would be interesting if someone has tried to correlate that to either geomagnetic changes or GCR changes (I realize those are different) or UV changes since I believe there are proxies for that as well. Marcus (#93), not a linear trend but a poorly fitted linear model. So poorly fitted it is quite obvious when placed side by side like barry did (#32). When the model has sensitivity changes over the course of years and decades, those need to be explained. A linear fit to CO2 would have a much lower slope and is pretty much linear from the physics (back radiation increases). The extra slope alleged to be WV feedback is produced by highly nonlinear processes and cannot be extrapolated (i.e. weather changes as the world warms). The "clouds" themselves (papers linked from #90) are a highly nonlinear dependency and in light of other terrestrial influences the correlation disappears over recent decades.
  45. The contradictory nature of global warming skepticism
    Wow Eric, that's weak-even for you. Delta T might fluctuate on a year to year basis, but there is still a LINEAR TREND over a multi-decade time frame (of roughly +0.16 degrees per decade). By contrast, there is absolutely NO EVIDENCE that neutron counts have any underlying positive or negative trend-which is what would be needed if they were to be having any long-term impact on temperatures. The "trend-line" is pretty close to y=0x-which is effectively a horizontal line. Also, in what way is the *fact* that clouds both trap outgoing Long-Wave radiation & reflect incoming short-wave radiation a "red herring"? Its completely relevant & also seriously damages your entire premise-which is probably why you're trying to call it a red herring. The reality is that, as much as you try to obfuscate, the link between clouds & the long-term global warming of the last 60 years is extremely tenuous-if not completely non-existent, yet you'd prefer to accept this idea, rather than the much stronger AGW theory-simply because the former sits well with your so-called "skeptical" outlook.
  46. The contradictory nature of global warming skepticism
    @BP References to James Jay Lee are a sure sign you're not interested in the science, but rather the political side of the debate. The point is not to scare people, the goal is to have a good idea of the potential risks we are facing so we can attempt to mitigate them. That is the reasonable thing to do. What is *not* reasonable is to tarry in taking action by claiming that we do not know enough, arguing there's no more warming (when looking at very short time frames) or trying to find a plethora of unlikely scenarios to explain something that's rather straightforward. "Hope for the best, prepare for the worst" is still one of the fundamental laws of survival...
  47. A detailed look at climate sensitivity
    BP - why do think I suggested that you look at CITES of the paper, rather than the paper? You think this problem is unstudied, unsolved and unsolvable? Firstly, using CRM - do you believe that these are developed without reference to empirical principles? Also cloud parameterization uses both CRM results AND observation results. The problem with reliance on observational results is that you cannot extrapolate with much certainty outside the range of observation parameters whereas a model from basic principles allows more confidence. I am sure you would be highly critical of parameterizations that extrapolated from observations. Also NS. Do you suppose that if NS turns up in engineering, we are forced to shrug shoulders and walk away? Of course not - there is massive toolkit for dealing with NS. And yes, this can involve trading confidence for solutions at boundaries for information loss within. And by the way, surely most of thermodynamics is laws of averages, (eg pressure, temperatures), for which there are fundamental problems doing derivations from true equations at all scales. I'd say most of the whole science of chemistry fits this as well. So are you really looking to understand limits and skill of models, or looking for excuses to dismiss them as fits another agenda?
  48. The contradictory nature of global warming skepticism
    #61 CoalGeologist at 11:48 AM on 12 September, 2010 Finally, as a scientist, I find your references to a "scare" and your use of the term "debunk" to be extremely offensive. Sorry for that. With the debunk thing I was just paraphrasing dana1981, the author of the article above. As for scare some people, like the late James Jay Lee are already scared out of their mind. "That means stopping the human race from breeding any more disgusting human babies!"
  49. A detailed look at climate sensitivity
    #43 Tom Dayton at 11:54 AM on 12 September, 2010 BP, scaddenp is quite correct in his astonishment at your statement that "the physics gets lost in the process. Equations governing averages can't be derived without being able to handle the true equations at all scales." No, he is not. Here is the paper he has referenced: J. Atmos. Sci., Volume 59, Issue 12 (June 2002) pp. 1917–1942. A Prognostic Parameterization for the Subgrid-Scale Variability of Water Vapor and Clouds in Large-Scale Models and Its Use to Diagnose Cloud Cover Adrian M. Tompkins The first thing to note is that there is nothing mysterious about "first principles". They are just the most thoroughly tested core of physics presented in a manner that is consistent and understandable. By "tested" I mean gazillion of actually performed experiments and careful observations, any of which could have falsified these principles, but failed to do so. Their understandability is also an indispensable criterion, because in certain directions human understanding has demonstrably more power than any algorithm. Of course understanding needs some algorithmic preprocessing of its input to be able to kick in, but then performs something no (Turingian) computing can ever do. Among other things this ability is in its prime in debugging. The preprocessing I have mentioned is for transforming the proposition to be understood into a very special (recursively modular) form. With some irreducible representations it simply can't be done, so there are things unattainable for us indeed. A computational climate model, which is transparent in this sense is still to be built. But back to your astonishment. You have probably heard of the Clay Institute's Millennium Prize Problems. These are extraordinarily hard and important mathematical problems, with a one million dollar prize for each (must be the least easy way to make a million bucks). Now, among these problems we can find the existence (or the lack of it) of well-behaved solutions of the Navier-Stokes Equation for reasonable initial conditions. These equations describe the motion of fluid substances, pretty basic stuff for e.g. GCMs, so the truly astonishing fact is that the science is not settled at all, not even the science of basic mathematical tools. And the existence problem of solutions to incompressible fluid motion is just the tip of the iceberg, there are many more unresolved tidbits around turbulent flows. Rather expensive wind tunnels are not maintained by mere accident in an age of supercomputers. And now let's see what Tompkins did. He has recognized the fact GCM performance depends not only on average humidity in grid cells, but also on finer details of its distribution inside the cells, that is, on higher moments like variance and skewness (or kurtosis, although he fails to mention this one), just like I was trying to show you above. Then, at least to my astonishment he proceeds as follows: "From the brief review of statistical schemes it is apparent that a widely varying selection of PDFs [probability density functions] have been used. One reason for this is that it is difficult to obtain generalized and accurate information from observations concerning variability [of humidity] down to small scales" Difficult, indeed. The traditional approach in cases like this is to consider the difficulty as a challenge and start working on ways to overcome it. It is quite astonishing how often this kind of attitude has been proven to be fertile. But instead of aiming for actual data, he is trying to circumvent the problem by resorting to a CRM (Cloud Resolving Model). That is, instead of going out and having a look or two at what's going on in nature, he applies another computational model, this time on a smaller scale. "The first aim of this paper therefore, is to use a 3D CRM, on domains on the order of a climate model grid box but also with relatively high horizontal resolution, to assess whether a generalized function form exists that can describe the total water variability" It would not be such a serious problem had he not called running a program an experiment and program output data. "Examination of the PDFs every half hour throughout the experiment proved them to be very similar in characteristics, since the computational domain was sufficient in size to continuously contain an ensemble of clouds, and the initial conditions were a realistic field of clouds in a state of quasi-equilibrium. The data at the 65 536 grid points are divided into 200 bins of equal width [etc., etc.]" Of course Gedankenexperiments were always legitimate tools of the scientific inquiry, but they are not substitutes for actual experiments or observations. Traditionally they were never used to settle the science, but to uncover holes in existing theory (to be filled later by either reshaping the theory or collecting relevant data). Note the CRM he has experimented with has the same Navier-Stokes equations in its belly, also gridded, therefore unable to handle sub-grid processes of its own. As flows tend to be turbulent down to microscopic scales (have you ever seen the fine threads of cigarette smoke?) and turbulence generates fractal structures, this model also has to be parametrized. In 3D flows (unlike in 2D ones) energy in small-scale eddies never gets negligible by shrinking through many orders of magnitude (this is the very reason behind the mathematical troubles). So. Water vapor distribution statistics presented in this paper are neither rooted in first principles nor in actual observations, they just hover in thin air (they do what vapor is supposed to do after all).
  50. Climate change: Water vapor makes for a wet argument
    Johnd - the question you need to ask is how fast would temperatures have dropped if there was NOT backradiation. Perhaps look at what happens on moon - okay not that fast because there is some heat capacity in the atmosphere. How about noting that temperature drop slower on a cloudy night? Now why is that? Instead of constantly referring to BOM stations with measurements in service of agriculture, why dont you look at a station where backradiation IS measured and you can see it. (eg Alice Springs). As to clouds, well dont forget clouds are both positive and negative feedbacks. In a stable climate, clouds are about the same. The question on actual interest is, as the earth warms from GHG increase, will clouds be a net positive or negative feedback and if so, by how much? While I am aware that there are speculative papers pushing for large negative feedback, this is incompatible with empirical measures of climate sensitivity. However, this is changing the goalposts - are you satisfied with the existence and effect of DLR (backradiation) yet?

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