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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 50851 to 50900:

  1. Add Frame and Stone to the List of Papers Validating IPCC Warming Projections
    Jeez, I respond to Klapper because I see that it has been a while with no response, and by the time I type it out, there are three.
  2. Add Frame and Stone to the List of Papers Validating IPCC Warming Projections
    Klapper (14), I suppose most of these talking points have been gone over before, but... Lower CO2 is not the only factor that was not (could not?) be predicted in 1990 which has reduced the rate of increase in the surface temperature. There has been an increase in Asian aerosols, the sun has been less active than usual, and the ocean has been warming at depth - which may or may not be related to the dominance of La Nina in recent years. Not sure, but it appears you are trying to imply that, because the explanation is complicated, it must be wrong. A model is just a way to approximate reality. Science works by replacing models with better ones, whether that is in chemistry, nuclear physics, what have you. So, if you are going to throw out the IPCC ensemble of models, what are you going to replace it with? If you are going to replace it with nothing, then you might as well be saying we don't know everything; therefore, we know nothing, and that conclusion really doesn't follow that premise. If you can show a model which does a better job over the last 20 years, as well as the over the historical record, that would be very interesting. Pretty lines on a graph with no connection to the laws of physics would not be very interesting.
  3. Add Frame and Stone to the List of Papers Validating IPCC Warming Projections
    Klapper @14, Re your claims concerning the FAR predictions, please look carefully at the figure inmy post @1 above and Figure 1 in the [main post]. You are applying a linear trend to a curve that is not linear, with the result that the resultant trend overestimates the amount of warming expected between the end points. Indeed, when done properly, the graphs above show excellent agreement between what was predicted for circa 2011 and what was observed. I sense that you are reluctant to accept that predictions made over 20 years ago, using pretty simplistic models by today's standards, have done remarkably well. Now please compare those predictions with those of "skeptics" and those in denial that are shown above. Your post contains at least one error. 2012 is probably officially going to be designated a La Nina year (yet it will very likely be the 9th warmest on record). As for 2013, it is still a little too soon to say, but the official forecast is for ENSO neutral conditions to persist into 2013. Your claim of a La Nina for 2013 misrepresents the official position of the CPC. But here again we have "skeptics" arguing about the noise (i.e., ENSO) when it has already been pointed out by climate scientists ad nauseum that it is pointless (and misleading) to focus on periods of time that are unable to extract a statistically significant signal from the noisy temperature record. Yet "skeptics" continue to play this disingenuous and scientifically meaningless game. FWIW, my simple box-type model is predicting a global surface air temperature anomaly for GISTEMP of about 0.61-0.65 C, so 2013 may tie or break the current global record (+0.64 C) without the boost of an El Nino. And think about this, barring a large tropical volcano blowing its top, 2013 will likely be warmer than 1998 was (+0.59 C), and that year followed a huge El Nino (a three plus sigma event if I recall correctly). If that happens it will impressive and speaks to just how much the positive radiative imbalance (from humans increasing greenhouse gases) is warming the planet. [Edited to fix typos, see square brackets]
  4. Add Frame and Stone to the List of Papers Validating IPCC Warming Projections
    Klapper @14: The actual FAR scenario that best fits the modern realized climate forcing is Scenario 2.5(D). This was discussed in detail in "Wall Street Journal 'Skeptics' Misrepresent the IPCC" by Keith Pickering, 3 March 2012. http://www.skepticalscience.com/wsj-skeptics-misrepresent-ipcc.html As Dana said too, you're ignoring GHG reductions in other forms like CFCs, which were banned by the Montreal Protocol only just before FAR was released. Furthermore, you're forgetting that since FAR was released there was an update to the forcing equations that the IPCC used, the new paper being Myhre et al 1998. The CO2 equation, ∆F = Aln(C/C_0), was A = 6.3 in FAR and A = 5.35 in Myhre et al 1998. In other words the IPCC was using a higher forcing per increase in CO2 than later research suggested to use. It's no wonder their prediction might be higher. ENSO predictions right now are neutral with a slight positive bias. I myself wouldn't bet on another La Nina. And there are ways, remember, to filter the ENSO signal anyway. Foster and Rahmstorf did this. If you really think that an El Nino will cause a spurious spike, then maybe we can just apply their methodology and remove it, and we'll see then. JoeT @17: They weren't just CO2 emission scenarios, they were total emission scenarios. The (1) and (3) points in Section 1.3.1 also tell why the projections aren't in line with the observations, which is because of natural variability that the projections did not model. So, if we include *only* present CO2 levels, of course they won't change much, but if we use the fuller 3D models and include the correct natural variability we have observed, the models will predict the temperature accurately. As to "the globally-averaged surface temperatures ... generally are in the middle of the scenario ranges," that is quite clearly demonstrated by Figure 4. The statement doesn't mean that it tracks the mean all the time, but the observations fall within the first standard deviation range without seeming to be biased toward one side of it.
  5. This is Global Warming - A Lesson for Monckton and Co.
    Was doing some further contemplation re my post above in terms of where we are in the "cycles" Lord Monkton has referred to. 60 years before 1998 it was 1938, so i'd say that was in the last "cooling phase of the ~60-year cycle of the ocean oscillations". from a chart here: it looks to me like around then we were also, broadly speaking, in a similar stage of low or decreasing solar activity. So, for arguments sake i will assume that the decade following 1938 has similar conditions in regard to solar and ocean "cycles" to what Monkton is claiming for the 1998 to now period. from a chart here: It appears that the temperature records show a quite rapid cooling over a decade or so. That's something i have seen on a lot of the charts depicting temp in the 20th century. Regardless of how different people treat the data, that didn't happen post 1998. Implies to me that there is some other factor at play now compared to then and the warming effect increased of CO2 levels would seem to be one of the candidates. My conclusion from this and reading other people posts here on this issue that really do make sense to me: Lord Monkton is perhaps not quite as smart as he thinks he is, and the most polite thing i can say about it is that he has rather blatantly shot himself in the foot with his published justifications for "16 years with no warming".
  6. Thawing of Permafrost Expected to Cause Significant Additional Global Warming, Not yet Accounted for in Climate Predictions
    … as a truly "emerging issue" (the effects of warming permafrost) could not have been included in climate change modelling to date. Really? This issue has been “emerging” and largely ignored by overly conservative scientists for a decade or more. It is not as though the effects of thawing permafrost have only become apparent in the last year or so. We have known for decades that roads, railways, pipelines, bridges and buildings resting on permafrost foundations would be disastrously compromised by thawing which creates poorly drained waterlogged landscapes lacking bearing strength. That permafrost embodies or covers significant methane deposits, preventing their release into the atmosphere is hardly new. Their presence, estimated quantity and their warming effects, if released by thawing permafrost have been reported on in peer-reviewed Papers for at least 20 years. Over the last decade many scientists have reported their findings on cryogenic carbon, the threat posed my thawing permafrost and warned of the potential for this feedback to bring about abrupt climate change. The broader climate science community have largely ignored their findings. Belatedly declaring this a “truly emerging issue” seems a feeble excuse for the way it has been and continues to be ignored by those engaged in climate science modeling.
  7. Debunking Climate Myths from Politicians
    Moderator, I accept that the "snipped" posts may have strayed from the topic 'Climate Myths from Politicians', but the accusations of deception leaves me perplexed. Deception was never my intent. The content of the posts were verbatim extracts from Parliamentary Hansard, accompanied by a link to the source documentation. Any perceived deception contained in the texts were not of my making.
  8. More ice loss through snowfall on Antarctica
    You are correct, the papers cited indicate that sub shelf is the most important not just one of the relevant processes. Thwaites Glacier is one location where the basal melt is leading to acceleration and rifting and calving losses.
  9. Add Frame and Stone to the List of Papers Validating IPCC Warming Projections
    KR: Thanks, that was very helpful. I want to make sure I understand a few things. As you pointed out, #4 says, "the bars on the side represent the range of results for the scenarios at the end of the time period and are not error bars." These are scenarios presumably for CO2 emission. But from Figure 1.6, the prior predictions for CO2 emission seem pretty good. Am I to conclude then, that if someone used the actual CO2 concentrations rather than the scenarios, the picture wouldn't have changed all that much? And if that's true, is that the reason why natural variablility, especially ENSO, is the dominating effect? It was also interesting to see that the report says, "Analyses by Rahmstorf et al.(2012; submitted) show that accounting for ENSO events and solar cycle changes would enhance the comparison with the AR4 and earlier projections." Which Dana shows very nicely in Figure 4 above. One issue especially bugs me. I can see that natural variability accounts for the discrepancy between the data and the scenarios. What i don't see is how "the globally-averaged surface temperatures ... generally are in the middle of the scenario ranges" after 2005 or so. They don't look like they are in the middle. Nor should they necessarily have to be.
  10. Add Frame and Stone to the List of Papers Validating IPCC Warming Projections
    JoeT - the hubub over Figure 1.4 is basically explained by the Ramhstorf paper I posted on earlier, linked at the top of this post. Basically surface temps are running on the low end of the model projection envelope because short-term effects have been in the cooling direction, but if you filter those out using the Foster and Rahmstorf methodology, it's smack dab in the middle. Klapper @14 - CO2 is not the only GHG. CFCs play a big role, as noted in the above post. We've already analyzed the numbers - net forcing vs. temperature. I'm not sure why you're trying to parse it out by only looking at a couple of GHGs instead of looking at the net forcing. Frankly I'm not sure what point you're trying to make.
  11. Klaus Flemløse at 07:39 AM on 19 December 2012
    Hurricanes aren't linked to global warming
    Hurricanes Worldwide 1970-2012
    Based on data from Maue, RN (2011): Global Frequency . I have studied the development of the number of tropical cyclones during the years January 1970 through September 2012 divided into the Northern and Southern Hemisphere. I would like to thank R.N. Maue for collecting data on tropical cyclones and making data public.
    The reason why I have made this analysis is that there have been mistrust in the climate skeptical world to the predictions made by IPCC, and using the data from R.N. Maue it should be possible retrospectively to verify or falsify the prediction made using elementary statistical tools. In addition to this, I was not aware of the differences found below between the Northern and Southern Hemisphere.
    The following graph shows the development of the number of tropical cyclones for the years January 1970 through September 2012.
    ”
    Please use zoom to see details.
    The number of Major Hurricanes is significantly growing in the Northern Hemisphere and the Southern Hemisphere, while the Tropical Storms are significantly decreasing in the Southern Hemisphere.
    This is in line with IPCC’s prediction of increasing number of Major Hurricanes and a decreasing number of Tropical Storms.
    Since hot sea water is the fuel for tropical cyclones, I understand why we will see an increasing number of Major Hurricanes. But I do not understand why the number of Tropical Storm is expected to decrease in the future as they already have done.
    There is a positive correlation between then number of Tropical Storm, Hurricane and Major Hurricane within the Northern Hemisphere and the Southern Hemisphere respectively.
    If you look at a shorter time span than 43 years, other observations could be made. For the years 2009-2012 the number of tropical cyclones is smaller than expected. However, 4 years are a too few years to put forwards a statement on a general trend. Please be aware that 2012 only includes 9 month so far.
    There is an apparent difference in the development of the number of tropical cyclones in the Northern and Southern Hemisphere. There is more tropical cyclone in the Northern Hemisphere, approx. 68% out of the total number of tropical cyclones.
    The following picture shows some of the differences between the Northern and Southern Hemisphere in respect of tropical cyclones:
    ””
    The tropical cyclone prone area is much large in Northern Hemisphere than in the Southern Hemisphere.
    When you look at number of Major Hurricanes per month, it appears that there is a remarkable difference in their distribution per month. In the following graph, I have shifted the month to produce frequency distribution by season.
    ””
    The number of Major Hurricanes for the Northern Hemisphere shows a left skew distribution with a gradually decreasing trend after the peak at the month of September, while the number of Major Hurricanes for the Southern Hemisphere shows a more abrupt decreasing trend after the peak at the month of March.
    The tropical cyclone season is 12 months for the Northern Hemisphere and 9 months for the Southern Hemisphere.
    There is a 6 and 12 month cyclic variation in the number of tropical cyclones. This follows from the seasonal shift between the Northern and Southern Hemisphere and from a spectral analysis not shown here. The following graph shows the number of Tropical Storms worldwide for the years 2000-2012 by month:
    ”
    I have used a generalized linear model with a linear trend and two harmonic terms with a cycle and 6 and 12 month to respectively in order to produce the graph above.
    Please use zoom to see details.
    The variation originates from merging the figures from the Northern and Southern Hemisphere, each with its own cyclic variations. The model explains 65% of the total variation. There is no significant trend and approx. 87 Tropical Storms are expected annually.
    In total the number of tropical cyclones in the Southern Hemisphere makes up 32% of the total number of tropical cyclones.
    The tropical cyclones prone area in the Southern Hemisphere makes up 42% of the total tropical cyclones prone area. This number is found by counting 5 * 5 degree squares on the map page 505 Marine Safety Information Chapter 35 Tropical Cyclones where tropical cyclones occur. As a first guess, this is probably OK to do so, but a better estimate is wanted.
    The number of tropical cyclones in the Southern Hemisphere, calculated in proportion to tropical cyclone prone area, equals 0.42*6690= 2803. The actual number is 2134. This is significantly lower.
    This leads to the following questions? 1) Why is the tropical cyclones prone area smaller in the Southern Hemisphere than in the Northern Hemisphere?
    2) Why is the number of tropical cyclones in the Southern Hemisphere in proportion to area smaller than the in the Northern Hemisphere?
    3) Are these findings in line with IPCC’s predictions?
    Atlantic cyclones - biased information As a result of the dominance of US based news media worldwide, the information about the tropical cyclones in the Atlantic region is more dominant than from the other parts of the world. This can lead to an incorrect understanding of trends and causes, since the number of tropical cyclones in the Atlantic region accounts for only 12.6% of the total number of tropical cyclones. The Atlantic Tropical Storms, Hurricanes and Major Hurricanes accounts only for 13.1 %, 12.7 % and 10.8 % of the total number of Tropical Storms, Hurricanes and Major Hurricanes respectively.
    More details can be found in the statistical analysis of tropical cyclone data from R.N.Maue Worldwide Hurricane analysis.
  12. Add Frame and Stone to the List of Papers Validating IPCC Warming Projections
    JoeT - "...this site has already commented on the leaked report." Fair enough. Read section 1.3.1 of that leaked report, which discusses the figure in question. First,
    ...the projections from the models were never intended to be predictions over such a short time scale...
    Section 1.3.1 goes on to state:
    There are several additional points to consider about Figure 1.4: (1) the model projections account for different emissions scenarios but do not fully account for natural variability; (2) the AR4 results for 1990–2000 account for the Mt. Pinatubo volcanic eruption, while the earlier ssessments do not; (3) the TAR and AR4 results are based on MAGICC, a simple climate model that attempts to represent the results from more complex models, rather than the actual results from the full three-dimensional climate models; and (4) the bars on the side represent the range of results for the scenarios at the end of the time period and are not error bars.
    They also do not, as a rule, include ENSO events except as emergent behavior in some of the models. Finally,
    In summary, the globally-averaged surface temperatures are well within the uncertainty range of all previous IPCC projections, and generally are in the middle of the scenario ranges. However, natural variability is likely the dominating effect in evaluating these early times in the scenario evaluations...
    Emphasis added. --- The GWPF and WUWT arguments about this (still in review) figure ignore natural variability, ignore that the models did not and do not predict ENSO, that earlier models did not include Pinatubo, and that the model ranges shown are not error bars. Climate models are appropriate for predicting 30 year averages, not the next five years in detail, and the skeptics (should have) have been around long enough to know that. In short, the GWPF and WUWT articles are a rather extensive misrepresentation of the figure discussed. "...full of sound and fury, Signifying nothing."
  13. Add Frame and Stone to the List of Papers Validating IPCC Warming Projections
    These graphs won't look nearly so convincing by the end of 2012. The original FAR prediction was for 1 degree C from 1990 to 2025 which works out to 0.28C/decade. The actual trend from 1990 to the end of 2010 from GISS is 0.186C/decade. However, the GISS trend to where we are now is only 0.160C/decade (with most of 2012 in). As for reduced GHG growth being the explanation, here are the numbers for CO2: forecast in 1990 from Figure 1.7 of Chapter 1 of FAR (approximately) 398 ppmv; actual for 2010 is 392. Is that drop in GHG emissions enough to drop the trend from 0.28 to 0.19? Hard to say. Methane also was way below forecast. FAR doesn't include a methane future growth graph. However they do note in Table 1.1 of Chapter 1 it was 1720 ppbv and growing at 15 ppbv per year. Actual growth since 1990 is much much lower, growing at less than 4 ppbv between 1990 and 2010 inclusive. Even if I agreed the actual to forecast miss for FAR is explainable by less than forecast GHG growth (I don't, at least not all of the forecast error), it will be harder to argue that going forward if La Nina conditions return in 2013 as currently forecast. (link attached) http://www.cpc.ncep.noaa.gov/products/CDB/Forecast/figf4.shtml The arguments coming back at me will be 2013 won't count because it is a La Nina year (if it does emerge as forecast). However, I have no doubt if you got an El Nino instead (and hence possibly another record) it absolutely would count and be further evidence of man-made climate change.
  14. CO2 effect is saturated
    curiousd @189, the modtran model is a Line by Line (LBL) model. That means, for a given specified set of atmospheric conditions it will calculate the IR radiation up or down at any given layer of the atmosphere from 0-70 km altitude; but it will not by itself adjust the atmospheric conditions to adjust for any change in radiative forcing. You, however, can perform the operation manually to determine the effect of a change in well mixed GHG concentration. To do so: 1) Open the model in two separate windows. 2) In the first window, set up your initial conditions. In my example this will be the default conditions of 375 ppmv CO2 and a clear sky tropical atmosphere. Note the Iout for those conditions. 3) In the second window, set "hold water vapor" to "rel hum" if you want to include the water vapour feedback, or to "pressure" if you want no feedbacks. 4) Set the change in CO2 or CH4 levels for the experiment. For my example I will double CO2 to 750 ppmv but hold CH4 constant. 5) Set the temperature offset until Iout matches that in the first window. In my example, with a water vapour feedback, that requires an offset of 1.48 C; or 0.89 C with no feedbacks. Other base settings will require different offsets. For example, for the experiment above except for mid-latitude winters, an offset of 0.77 C is required to maintain radiative equilibrium with no feedbacks; and 1 degree C with a water vapour feedback. It may seem that if you calculated the values for a number of conditions and determined area weighted values based on the area in which those conditions apply across the Earth, you could determine the the net radiative effect with an LBL model. That is not so, firstly because it only incorporates one of many feedbacks; and secondly because in the real atmosphere a change in radiative forcing will also result in changes in lateral energy transfers, so that radiative equilibrium need not be held at each location but only across the whole planet. Of course, it is easy to show with an LBL model that temperatures increases are required under all conditions with an increase in CO2 level to maintain radiative equilibrium so that the planatary Mean Surface Temperature must increase to maintain global radiative equilibrium - but that only tells you that there is an effect, not its precise magnitude. Global Circulation Models fill the gap by automatically changing atmospheric conditions at each location based on change in radiative forcing, changes in temperature, and changes in lateral energy transfer. Unfortunately, I know of no GCM with a convenient web interface like that of ModTran.
  15. Add Frame and Stone to the List of Papers Validating IPCC Warming Projections
    KR, As in the link you provided, this site has already commented on the leaked report. This is why I come here -- we're going to see this stuff get played out all over the place. It's important to get the rebuttal out as soon as possible, which was the purpose of Dana's post -- you know, the one that you linked to. AlexC, Yeah I read that section (& only that so far). Frankly I was hoping that Dana could provide more insight than I have, since it is directly related to the post he wrote above.
  16. Add Frame and Stone to the List of Papers Validating IPCC Warming Projections
    Smith - models do volcanic by throwing in eruptions based on global average. This is of course no prediction of exactly what year they will occur in but if this wasnt done, then the lack of volcano aerosols becomes a forcing. Hindcast model can of course use the actual volcano predictions. Similar, solar is put in based on what is expected of the solar cycle though hindcasts can do exactly what happened. ENSO is not really a forcing - it a mode of internal variability. There are models focussed specifically on predicting ENSO because of its meteorological importance but they have very limited success so far. Instead ENSO-like behaviour emerges from the models but this is a chaotic phenomena and so model outputs are not good predictors of actual ENSO. For this (and other issues with internal variability), models have very little skill at decadal or less prediction. They are after all climate models - targeting at predicting what will happen to 30 year averages. What you can expect for climate has be result of averaging many different runs with different initialisation and likely forcing scenarios.
  17. Add Frame and Stone to the List of Papers Validating IPCC Warming Projections
    Further to KR WUWT seems a very efficient anger factory, or at least anger is a major byproduct. In that connection it's worth consideration of research indicating induced emotions may be addictive in some senses of the word.
  18. Doha Climate Summit Ends With No New CO2 Cuts or Funding
    Tks for posting my IPS article. In my personal opinion little will change unless people march on their respective capitals demanding action and refuse to leave until it happens.
  19. Add Frame and Stone to the List of Papers Validating IPCC Warming Projections
    Actually never mind, it appears you indeed do have access to the chapter.
  20. Add Frame and Stone to the List of Papers Validating IPCC Warming Projections
    JoeT - following KR's good sense to not go into detail on a leaked report, but also to try to help some more with your question, if you have by chance actually been able to obtain a copy of the draft, it would help to read the text accompanying the graphic in the section it appears in. Chapter 1.3.1 is where you'd find that discussion, and where you'll see just how dishonestly WUWT et al are touting Figure 1.4.
  21. Add Frame and Stone to the List of Papers Validating IPCC Warming Projections
    JoeT - And no, it's not a surprise that the folks on WUWT are worked up. That's what they do - take something out of context, or wrong, get worked up, and make a great deal of noise as if it were the "game changer" for climate science. Sigh. "...it is a tale, Told by an idiot, full of sound and fury, Signifying nothing." - Macbeth
  22. Add Frame and Stone to the List of Papers Validating IPCC Warming Projections
    JoeT - As per the IPCC Draft Report Leaked thread, it's entirely inappropriate to be commenting on something that is (a) a draft, and thus likely to change in some aspects before publication due to reviewer comments, and (b) a work that is only publicized due to the violations of confidentiality by one of those reviewers. If you wish to comment or query regarding one (or more) of the published papers the IPCC may refer to in the draft, in regards to the data and conclusions of those published works, that's another matter entirely - please do.
  23. More ice loss through snowfall on Antarctica
    mispelto @#4: Thank you for your prompt response to my initial request. A follow-up question: The first sentence under the header, “Sea-level is rising – that is a fact” of the OP is: A number of processes are relevant for ice-loss in Antarctica, most notably to sub-shelf melting caused by warming of the surrounding ocean water. I presume that the term "sub-shelf melting" is equaivalent to "basil melting." Am I correct?
  24. CO2 effect is saturated
    Question: If I run Modtran, the number given as "ground temperature" is, in the tropical atmosphere setting, the same whether I turn off all the greenhouse gases (CO2, water vapor, methane, ozone) or leave defaults. The ground temperature in the tropics is 299.7 K with or without GHG. I don't think this can be right? Help?
  25. Add Frame and Stone to the List of Papers Validating IPCC Warming Projections
    Dana, Since it's related to this post, I'm hoping that you would comment on Figure 1.4 in Chapter 1 of the IPPC draft. It seems to have the people at WUWT all worked up (and now my head hurts from reading the comments there).
  26. Add Frame and Stone to the List of Papers Validating IPCC Warming Projections
    Smith, I believe the 1990 IPCC report only used a simple model forced by GHGs, whereas more modern climate models also simulate natural forcings as well as internal variability.
  27. Add Frame and Stone to the List of Papers Validating IPCC Warming Projections
    Do the GCMs have any component which takes into account variations in solar, volcanic or ENSO?
  28. Dikran Marsupial at 02:23 AM on 19 December 2012
    This is Global Warming - A Lesson for Monckton and Co.
    BTW, the results will vary according to the dataset you chose, but the 1997-current confidence interval is so large that they will all include a continuation of the long term trend. It is a bit ironic though that the dataset produced by the climate skeptic is the one that shows the most warming!
  29. Add Frame and Stone to the List of Papers Validating IPCC Warming Projections
    LarryM @#2, In the interest of full disclosure, those words of mine were inspired by those of Dr. Pierrehumbert, whose AGU talk I had the good fortune to watch in person. PS: Tks for fixing my broken link DB.
  30. Dikran Marsupial at 02:15 AM on 19 December 2012
    This is Global Warming - A Lesson for Monckton and Co.
    On the topic of "no warming since [insert cherry picked date here]", if you go to the SkS trend calculator and compute the long term trend (1979-present) for the UAH dataset (produced by climate skeptic scientist Roy Spencer), you will get a trend of 0.138 ±0.074 °C/decade (2σ). Next, lets compute the trend from 1997 (the start of the "hiatus"), which turns out to be 0.090 ±0.232 °C/decade (2σ). This is clearly not statistically significant as a zero trend lies within the confidence interval. However, the long term trend of 0.138 °C/decade also lies well within the confidence interval, so the observations are also consistent with there having been no hiatus in warming, but just steady warming at 0.138 °C/decade with some perturbations superimposed on it due to e.g. ENSO. Furthermore, the long term trend of 0.138 °C/decade is closer to the estimated trend than a zero trend is, so the continuation of the long term trend is marginally more consistent with the observed trend than a hiatus. Essentially Monckton is making a statistical error in thinking that the lack of statistically significant warming implies that there is statistically significant evidence for stasis. The statistics are equivocal, they rule out neither a continuation of the underlying warming trend, nor the existence of a hiatus in warming. The difference between the scientific mainstream and the skeptics on this is that mainstream scientific opinion on AGW is not predicated solely on a 16 year trend (there are many other lines of evidence e.g. OHC and a lot of basic physics), whereas the existence of a hiatus is predicated pretty much purely on the lack of a statistically significant warming.
  31. Add Frame and Stone to the List of Papers Validating IPCC Warming Projections
    Speaking of climate predictions by real scientists, both right and wrong, see the excellent lecture by Ray Pierrehumbert at this year's American Geophysical Union (AGU) meeting (lecture starts at 4:18). Like Albatross, he too states that being wrong sometimes is OK (it's the "great teacher"), as long as one learns from one's mistakes and doesn't double-down on the wrongness as some like Lindzen and Christy tend to do.
  32. Add Frame and Stone to the List of Papers Validating IPCC Warming Projections
    Interesting. It also highlights the fact that fake skeptics rarely invest the effort to make predictions, and when they do, they rarely (if ever) revisit their predictions. The reason for them not doing so is clear, they do not have a robust theory (e.g., anthropogenic global warming) on which to base their predictions, so any predictions they make invariably falter after a very short time (e.g., McLean's disasterous attempt). Here are a few more failures by fake skeptics: [Source] Now it is OK to be wrong sometimes, but all the time? And to never learn from those mistakes, but rather just keep recycling the same old tired debunked nonsense about cycles etc.? No thanks, I'll stick with the real climate scientists.
    Moderator Response: [DB] Fixed link.
  33. This is Global Warming - A Lesson for Monckton and Co.
    DSL - I believe catamon is in agreement, which is why he/she pointed out that temperatures are holding steady despite low insolation, ENSO, ocean oscillations, etc. If the "no warming" crowd was correct (which they aren't) those cyclic influences should be leading to climate cooling, rather than a hiatus, and it's the underlying warming trend adding up to the current (but not everlasting) slow changes.
  34. This is Global Warming - A Lesson for Monckton and Co.
    Catamon, the escalator in the upper right is highly relevant. Consider that during the "hiatus" period, there is a stretch from 2000-2007 where the linear trend is an alarming .02569C per year. And for the 90th time, surface temp is about the least useful of measures of global warming (Hadley in particular). Show me the parallel hiatus in OHC (steady as she goes) and global ice mass loss (loss accelerated).
  35. This is Global Warming - A Lesson for Monckton and Co.
    catamon - What happens when these various cyclic cooling influences reverse? Well, we would expect that it's going to get a great deal warmer as the temperatures regress to the mean of the trends. I find these "16-year" claims simply appalling, personally. I would like to point out certain aspects of the data: [Source, using HadCRUT4] The last 16 years or so appear rather flat (at least for HadCRUT data, not so much for GISTEMP), but 16 years is too short a time period for statistical significance. A quick check is to look at the trends for 17 or for 15 years, and note significant differences - a sign of a not too robust conclusion. Even more importantly, consider that last 16 years (cherry-picked to start with a very strong El Nino, ending with several La Nina's) with respect to the rest of the data. The 22 year trend 1975-1997 is ~0.16°C/decade. If you include the data to the present, if you include the 16-year "no-warming" trumpeted by Monckton, the 1975-present trend is 0.17°C, a higher trend than that of the first 22 years! In other words, if you look at enough data for significance, you see that even the claimed "no warming" data is still showing an accelerating trend - and that Moncktons claim is simply an artifact of deliberately cherry-picking from the noise.
  36. This is Global Warming - A Lesson for Monckton and Co.
    catamon: Thinking things through viz. climate is not Monckton's forte. I believe you have hit the nail on the head with:
    The question is then, what's keeping us warm if not CO2 and what happens when CO2 levels are higher than now, and there is strong solar activity, and we are in a warming phase of the 60 year cycle of ocean oscillations, and there is an El Nino??
    which Monckton clearly has not let disturb his mind.
  37. This is Global Warming - A Lesson for Monckton and Co.
    Ok, people riddle me this, and please correct me if i am misunderstanding. I have seen it written on no less reliable site that the Lord Monktons himself that: "The 16-year temperature stasis that has now occurred must be explicitly faced." and: "one might argue that the relatively weak warming signal from CO2 has been overlain by three recent natural influences: in late 2001 we entered a ~30-year cooling phase of the ~60-year cycle of the ocean oscillations; the current ~11-year solar cycle displays near-unprecedentedly weak solar activity, implying the possibility of a Dalton or even Maunder minimum in the coming decades; and there has recently been a double-dip La Niña." So, for arguments sake i'll make a perhaps bold assumption that the above quotes are believable. That means that with 3 theoretically cooling influences referred to currently in play, we are in a "temperature stasis", not measurably cooling as i would expect. The question is then, what's keeping us warm if not CO2 and what happens when CO2 levels are higher than now, and there is strong solar activity, and we are in a warming phase of the 60 year cycle of ocean oscillations, and there is an El Nino??
  38. New research from last week 50/2012
    Ari Thank you so much for these posts. I will miss them but understand you have to move on. Shoyemore Great little background on Stoney. Thanks Tony
  39. Stratospheric Cooling and Tropospheric Warming - Revised
    All, that would be N2O (nitrous oxide), not NO2 (nitrogen dioxide)
  40. More ice loss through snowfall on Antarctica
    The basal melting I am referring to and is discussed in the resources is at the bottom of ice shelves. This is where the magnitude of basal melting is crucial in terms of ice thickness and hence stability of the ice shelves. Under the ice sheet it is not the amount of melt that matters it is really whether it is melting or not that influences flow.
  41. 2012 SkS Weekly Digest #50
    Ok, ok, so the world is going to crap and the Earth is headed for Venus style runaway greenhouse, but we can at least get our literary quotes correct... Winston didn't say it first, I always thought it was Mark Twain but I found this article.. "A lie can travel halfway round the world while the truth is putting on its shoes". - This quote has been attributed to Mark Twain, but it has never been verified as originating with Twain. This quote may have originated with Charles Haddon Spurgeon (1834-92) who attributed it to an old proverb in a sermon delivered on Sunday morning, April 1, 1855. Spurgeon was a celebrated English fundamentalist Baptist preacher. His words were: "A lie will go round the world while truth is pulling its boots on."
  42. CO2 effect is saturated
    Never mind! Sorry. I now realize I was fooled by a cartoon drawing of the tropopause.....for an appreciable change in altitude in a realistic drawing the temp almost stays constant. Maybe that is why it is called a "pause".
  43. 2012 SkS Weekly Digest #50
    The video of Sen speech is the fragment about the burden of climate change on our grand/children. This video from 6:00 to 9:00 when Sen Whitehouse explains the escalator, is the key fragment for us to watch. He does an excellent job in choosing strong and precise words to describe the denialism surrounding the temp data. A classic speech well worth watching.
  44. New research from last week 50/2012
    So Stoney is his last name. I just read "Stoney G. Johnstone" and thought Johnstone was his last name. :) Corrected. You know, as I stop making these weekly new research posts, it leaves me more time to dig up the old gems. I just don't know yet how I will publish them, but I'm sure I'll come up with something.
  45. CO2 effect is saturated
    Thank you. There are unexplained things in these models. Next question. If you run the "NCAR visible + IR Rad Code" for the default parameters,the first upper left hand graph shows no increase in temperature with altitude once you get to the height of the tropopause. In other words the temperature just stays constant with height after the tropopause. Is this peculiarity because there is no stratospheric ozone in the model?
  46. IPCC Draft Report Leaked, Shows Global Warming is NOT Due to the Sun
    Calling Mr. Rawls. Mr. Rawls, are you in the building? Can you come to the comment stream and defend your integrity? It's taking quite a beating. Dale was unable to render life support. Indeed, he appears to have accidentally dropped a bottle of oxygen on what was left.
  47. IPCC Draft Report Leaked, Shows Global Warming is NOT Due to the Sun
    Let's sum up here. brr is arguing that there may be a solar factor which amplifies the TSI forcing. I have no problem with that - there may very well be. brr claims this is Rawls' entire argument, which is not true. As Tom notes, Rawls also claims that solar amplification could account for a significant amount of the warming over the past half century. That argument is discussed in the "Physical Reality Intrudes on Rawls" section in the above post. So brr, now that I've agreed that there might be a solar amplification factor, are you willing to admit that such a factor could not account for the recent global warming, given that solar activity on the whole is down over the past 60 years?
    Moderator Response: [DB] Note that brr is yet another sock-puppet of banned user Dale...and has also recused himself from further participation here.
  48. Philippe Chantreau at 11:26 AM on 18 December 2012
    More ice loss through snowfall on Antarctica
    John, I believe that basal melt is melting that occurs at the base of the ice layer (i.e. between the ice and the underlying ground), where the liquid water layer acts as a lubricant and enhances glacial flow. If I remember Mauri's other explanations, that lubrication effect has the potential of increasing the flow of a glacier in rather spectacular fashion, as has been seen already in the Northern hemisphere.
    Moderator Response: [DB] Note that you describe the Zwally effect. This is explored in-depth in this SkS post, itself based heavily on input from Mauri himself.
  49. IPCC Draft Report Leaked, Shows Global Warming is NOT Due to the Sun
    Newsflash: In breaking news, Alec Rawls finds (-snip-). Claims refutation of altitudist dogma that Everest's summit is the highest location on Earth. Anthony Watts breathless with anticipation of this new, ground breaking revelation.
    Moderator Response: [DB] Inflammatory snipped.
  50. IPCC Draft Report Leaked, Shows Global Warming is NOT Due to the Sun
    brr @98, actually Rawls point was that:
    "The admission of strong evidence for enhanced solar forcing changes everything. The climate alarmists can’t continue to claim that warming was almost entirely due to human activity over a period when solar warming effects, now acknowledged to be important, were at a maximum. The final draft of AR5 WG1 is not scheduled to be released for another year but the public needs to know now how the main premises and conclusions of the IPCC story line have been undercut by the IPCC itself."
    What he has is the fact that the IPCC mentions a possibility (note again, "seems" does not mean "is") that total solar forcing is greater than 0.01667 of total anthropogenic forcing (ie, the ration of solar forcing to anthropogenic forcing). From this he concludes that the "admission ... changes everything" and "The climate alarmists can’t continue to claim that warming was almost entirely due to human activity over a period when solar warming effects, now acknowledged to be important, were at a maximum." Well, I have news for you. Acknowledging that something may have made more than a 1.667% contribution to the warming is not acknowledging that it is important. Further, you could increase solar forcing by a factor of ten, and the warming would still be "almost entirely due to human activity". Surely anybody competent enough to understand simple arithmetic can understand this.

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