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Comments 72101 to 72150:

72101. Eric (skeptic) at 20:39 PM on 19 October 2011
       Continued Lower Atmosphere Warming
       Dikran, regarding your question about the statistical significance of the difference in trends 1979-2002 and 2002-present, it depends on the assumptions about the domain (in this case TLT). Could you please point out where those assumptions are described?
72102. Bart at 19:36 PM on 19 October 2011
       Greenland ice loss continues to accelerate
       Could anyone indicate where exactly I can find the data as presented in figure 2 above? That woulod be very helpful!
72103. Dikran Marsupial at 18:31 PM on 19 October 2011
       Continued Lower Atmosphere Warming
       Prof. Pielke You have put forward the hypothesis that "the 9 year trend during this time period [2002-present] is different than the trend for the time period [1979-2002].". Do you agree that the difference between these trends is not statistically significant, yes or no?
72104. Glenn Tamblyn at 17:09 PM on 19 October 2011
       How Increasing Carbon Dioxide Heats The Ocean
       This is an interesting post Rob. I wasn't aware of the particular impact of skin temperature changes on the heat transfer balance. Bob Loblaw @9 The interesting challenge is actually the movement of heat from the skin to just below that without this heat returning to the atmosphere. Once it is down in the sub-surface waters there are a range of mixing processes that will move it down further, down to 50-100 metres. This upper layer of the ocean is referred to as the Well-Mixed Layer. Its depth varies around the world and the seasons but is typically less than 100m. Here various mixing processes dominate; wind, waves, tides, even the movement of organisms - megatonnes of krill, zoo-plankton and phyto-plankton moving vertically over the course of a day can have a surprising impact. Once additional heat has reached this depth, over-turning currents within the oceans can carry it further down. The major overturning current flows, mixing the surface with the abyssal depths happen in several defined regions in the oceans. But lesser flows and gyres exist in some locations that can move heat further down without reaching the bottom. Also, this mechanism explains well the underlying thermodynamics of 'in-the-pipeline' warming. This is sometimes portrayed as if at some future time all this heat will start 'coming back out' from the oceans. But this doesn't make thermodynamic sense. Prior to AGW, the temperatures of the air and ocean would have been in some sort of thermal balance. Not necesarily the same temperatures, but at temperatures where the heat fluxes between ocean <-> air where in balance. So as AGW starts adding heat to the atmosphere & oceans the much lower thermal mass of the atmosphere would mean that the temperature of the atmosphere starts rising faster than the oceans - which we have observed. Thus the temperature differential between oceans and air starts to change, creating a 'brake' on the rate at which atmospheric temps can rise. If atmospheric temps rise faster than ocean temps, this will tend to increase the energy flow from air to oceans, limiting the rise that is possible in the air until the temp change in the oceans 'catches up'. Not a heat flow from oceans to air 'later' warming the air. Rather a heat flow from air to oceans limiting the rise in air temps 'now' until this flow subsides when the temp imbalance is rectified as the oceans warm. Looking at Rob's 4 step process, step 3 - 'surface layers become warmer than atmosphere'. If the atmosphere warms, then the surface layers are warmer compared to the oceans, but not as much as before. Therefore step 4 - 'ocean looses heat to cooler atmosphere above'. They don't loose as much and retain more. Since the oceans aren't losing as much to the air, heating of the air is restricted while heating of the oceans is enhanced. But there is a lot of ocean. Its not heat coming out of the oceans that is 'in the pipe-line'. It is heating of the oceans eventually taking the brake off heating of the atmosphere that 'is in the pipeline'
72105. barry1487 at 15:30 PM on 19 October 2011
       How Increasing Carbon Dioxide Heats The Ocean
       @7: Glenn Tamblyn Thanks for the breakdown. I'm familiar with TCS and ECS, and was curious about the choice of running with the Charney sensitivity as opposed to effective (immediate) response or long-term sensitivity. I googled about after reading your reply and rediscovered this post from realclimate. http://www.realclimate.org/index.php/archives/2008/04/target-co2/
72106. barry1487 at 15:20 PM on 19 October 2011
       How Increasing Carbon Dioxide Heats The Ocean
       @9: Great addendum, Bob. The exposition on this sub-topic really highlights, for me, the challenges when deciding how much complexity (and uncertainty) to sacrifice in order to describe scientific understanding to lay people. There will always be genuine questioners who want more detail, as well as queries from people less curious and more disposed to find or expose fault, incompetence or iniquity. So there will always be a need for new posts here. Having lurked here for several years, I enjoy SkS as a conversation as well as resource for rebuttals. Topics are returned to and refined. It has been a pleasure watching arguments and explanations unfold and evolve, and I really appreciate the time taken to engage with my own queries.
72107. Tom Dayton at 13:39 PM on 19 October 2011
       Continued Lower Atmosphere Warming
       Adding to muoncounter's reply, since the signal we are interested in is the long term trend, then by definition all the short-term changes are noise interfering with us detecting that signal, even if those short-term changes are measured without error.
72108. muoncounter at 13:32 PM on 19 October 2011
       Continued Lower Atmosphere Warming
       pielkesr#88: "It says nothing about the long term trend, but it certainly not "noise" as long as the measurements are robust." I beg to differ: Robust measurements of a noisy signal may indeed be noise. That's a commonplace problem in seismic exploration. Much effort in geophysics goes to the improvement of SNR through acquisition methods; the noise may be reduced, but it is always there. Look to particle physics for other examples: are those faster-than-light neutrinos signal or noise? Are GCRs 'signal' against a background of solar cosmic ray 'noise'? Both are present in very robust measurements.
72109. Bob Loblaw at 13:15 PM on 19 October 2011
       How Increasing Carbon Dioxide Heats The Ocean
       One concept that is useful in understanding these sorts of exchanges is the "surface energy balance". For the case of the ocean, think of the ocean-atmosphere interface as a plane surface separating the ocean and atmosphere. This plane has no mass, so it can't store energy. With no capability of storing energy, the fluxes of energy towards and away from the surface must sum to zero. You can express this in mathematical terms. There are variations depending on what you decide to call + and - for fluxes, but one convenient form is: net radiation = sensible heat + latent heat + ocean heating where net radiation is the sum of incoming radiation (solar and IR) minus outgoing (reflected solar and upward-emitted IR), sensible heat is thermal energy transported into the atmosphere, latent heat is the energy of evaporation transported into the atmosphere (i.e., the flux of water vapour, expressed in energy terms), and ocean heating is the flux of heat into the ocean. With the water surface allowing penetration of solar radiation, things are really a bit more complex than this, but it still serves as a useful model. I'm also ignoring chemical reactions, for simplicity. (Photosynthesis would be the largest of these, and is still quite small.) The sensible heat flux is dependent on the temperature gradient between the surface and the lower atmosphere (and wind and a few other details). The latent heat flux is dependent on the humidity gradient between the surface and the lower atmosphere, but due to the condition of vapour saturation at the water surface, the latent heat is also dependent on surface temperature. Lastly, the flux of heat into the ocean is also dependent on the temperature gradient away from the surface (and the rate of mechanical mixing). Of the radiation terms, only the outgoing IR is strongly dependent on surface temperature (unless you run into freezing or thawing). The usefulness of this model is that it helps illustrate how surface temperature is linked to the energy fluxes. Stop mixing the air, and you reduce the fluxes into the atmosphere. Response? Surface temperature rises, increasing the fluxes again - but more will go into the ocean. Restrictions on evaporation (easier to image on a land surface) will cause a rise in atmospheric and sub-surface heating. Mix the ocean more (wind), and more heat is carried into the ocean leaving less flux into the air (both heat and vapour). Both the ocean and the atmosphere will exhibit stratification effects. The atmosphere, when heated from below, will become unstable and mix more easily; when cooled from below to the point of a strong temperature inversion, heat (and vapour) transfer is limited due to the reduced mixing. Wind affects waves, which affect solar absorption, too, so there is lots to keep track of in developing a comprehensive mathematical model. But you can still end up expressing it in a form where each component is a function of surface temperature plus some other terms, and if you can define the other terms you can solve for surface temperature.
72110. scaddenp at 13:15 PM on 19 October 2011
       El Niño: Unaffected by climate change in the 21st century but its impacts may be more severe
       Adrian, instead of referencing a propoganda piece, how about directly referencing the peer-reviewed research that backs your claim. Then we can have a serious look at it. I wonder though. Would you continue to trust a source (eg Pat Michaels) even if shown to be producing disinformation? If you will uncritically accept information so long as it says what you want it to, then there is little point discussing points with you except to ensure others are not led astray.
72111. Fran Barlow2 at 13:14 PM on 19 October 2011
       Correction to the True Cost of Coal Power - MMN11
       

       Economists who apply a high discount rate in calculating the real cost of coal are not intentionally dismissing the cost to future generations. What they are doing is expressing their belief that the future effects of climate change on the economy will be much below those anticipated by science and most climate scientists. From a commercial perspective, it could be argued that they are telling us that short term profitability is far more important than reducing the future effects of climate change.

       Or put another way, they think spending money now on mitigation or adaptation or any other measure designed to avoid harm in the future will not create as much benefit in the future as doing nothing specific (or only so much) about the future impacts of climate change. Imagine that you knew that you were going to die in 12 months time. Someone offers you a fabulous investment which matures in 11 months. The benefit is enormous but you only get to enjoy it for one month. A much less fabulous investment that gives you some benefit from day one might be better. How can you work it which is better? You apply a suitable discount rate. The other thing is that we humans have to deal with uncertainty. We don't know for example, that in the future some presently unknown suite of technologies won't make it possible for people to scoff at our concerns for their safety and well-being. Foregoing our well-being now for people who may be better off than we are in the future, seems unreasonable, especially if it can be argued that we may actually be making them worse off (following the above logic on future benefits). Moreover, if you ask people how concerned they are about their children's life chances, they tupically put a high value on this. Ask about those of their grandchildren, and once again, a high value follows. These things are existential because we want people who have been born early enough to know us to think well of us after we die. This is as close as we get to immortality. Yet if one asks what one thinks about the interests of people born 100 years from now, the concern is far more diffuse. Sure in a general sense we'd like not to prejudice their chances, but it's hard enough for people to imagine the world in 2111 let alone have concern for the people being born then. They may think us as foolish as we think of the folk in 1911, and perhaps more so, but as we will never have met them, most feel less concern. Hence, benefits for these people are less important than benefits for us now. Let me say that this is not my view. IMO, we have an absolute and minimal obligation to do whatever we reasonably can to hand over the biosphere in no worse condition that it came to us. Now that we know that the generations before us acted first in ignorance and then in reckless disregard of sustainability, we are bound to play a robust part in clearing up the mess, rather than making it worse. That IMO, is many times more important than passing on the family home to the kids or not creating financial debts for future generations. This is especially important because some of the harms authoried during the last 100 years are being visited upon people right now, and the IPCC projections strike me as somewhat optimistic.
72112. Steve L at 12:26 PM on 19 October 2011
       How Increasing Carbon Dioxide Heats The Ocean
       A couple of questions I came up with while skimming this. (1) How was the cooling effect of evaporation controlled for in the Tangaroa study? I think I read that light (not just heat) increases evaporation considerably. (2) There's something counter-intuitive here -- ignoring the mechanistic explanation, it seems like you're saying that stratification increases the mixing down of heat. I'm wondering how much this relies on diurnal heating. If just not diurnally heating and cooling, but just receiving an intermediate amount of solar energy constantly, wouldn't stratification slow the warming of the ocean? Cooling allows the warm layer to sink? Doesn't it sink below a warmer layer which then loses its heat to the atmosphere? I suppose I could read the links provided before asking ignorant questions!
72113. Glenn Tamblyn at 12:23 PM on 19 October 2011
       How Increasing Carbon Dioxide Heats The Ocean
       Barry @4 Climate Sensitivity is defined in terms of three different time scales. - Transient CS is days/weeks/ maybe a year. This is mainly radiative effects - GH gases, Water Feedback, Aerosol changes due to pollution or volcanoes. - Short Term CS is decades out to around 50 years - this is the one you are referring to. This takes acount of changes in sea ice, movements in weather patterns, upper ocean heat changes etc. This is the one commonly referred to as Climate Senstivity in the literature when they aren't being more specific. It is also called the Charney Sensitivity after the scientists who first coined the term in the Charney Report. - Long Term CS is centuries to even millenia long. This includes effects like whole of ocean warming, Land ice changes, major changes in vegetation patterns, desertification, changes in ocean circulation pattern, methane feedbacks from permafrost and clathrates etc
72114. Albatross at 11:33 AM on 19 October 2011
       Comparing Global Temperature Predictions
       Nice plots Icarus. It would be nice to include those data from Hansen's 1981 paper in the above figures.
72115. KR at 11:17 AM on 19 October 2011
       El Niño: Unaffected by climate change in the 21st century but its impacts may be more severe
       Sphaerica - SourceWatch lists that site here; it's 'a blog published by New Hope Environmental Services, "an advocacy science consulting firm" run by ... Patrick J. Michaels' (emphasis added). adrian smits - The translation of "advocacy science consulting firm" is "lobbying group". Their posted information will be biased towards their customers - not a good place to look for science.
72116. skywatcher at 11:16 AM on 19 October 2011
       Continued Lower Atmosphere Warming
       Dr Pielke, can you agree with the following statement: "The TLT temperature trend from 2002-present is not statistically significantly different from the TLT trend from 1979-present. We must therefore assume, in the absence of data to the contrary, that the significant trend from 1979 to present continues." Yes or no? Additionally, what fraction of the world's oceans is 0-700m? Why not consider a greater fraction of the world's oceans, as pointed out to you by Albatross on the linked thread? It looks to me like a few Joules of heat are accumulating between 700-2000m.
72117. Rob Honeycutt at 10:58 AM on 19 October 2011
       El Niño: Unaffected by climate change in the 21st century but its impacts may be more severe
       Sphaerica... In the "Staff" section we find... Chief Editor: Patrick J. Michaels Contributing Editor: Robert C. Balling, Jr. Contributing Editor: Robert E. Davis Administrator: Paul C. Knappenberger So, I think you're correct. This is a CATO funded site. What was Michaels' quote? That 40% of his funding comes from oil interests? I think that's accurate.
72118. Riduna at 10:54 AM on 19 October 2011
       Correction to the True Cost of Coal Power - MMN11
       Economists who apply a high discount rate in calculating the real cost of coal are not intentionally dismissing the cost to future generations. What they are doing is expressing their belief that the future effects of climate change on the economy will be much below those anticipated by science and most climate scientists. From a commercial perspective, it could be argued that they are telling us that short term profitability is far more important than reducing the future effects of climate change. There is of course another view, that retaining coal production and use are essential to protecting the comparative advantage and competitiveness of countries now heavily dependent on fossil fuel use. Those who espouse this view ignore the fact that countries implementing policies to minimize use of coal and oil (eg. Sweden, France and other EU countries) have not experienced commercial disadvantage. In Australia, where the Opposition Leader (Tony Abbott) and his spiritual mentor (Cardinal Pell) have both denied AGW and its expected effects this century, government has placed a price on carbon. In doing so, it has ignored Green Party demands for coal and oil to be priced taking into account the true cost of externalities and named a starting price of $23/tonne CO2. This price appears to have been calculated having regard to the need for a clear price signal to investors in electricity generation, more efficient use of electricity, and the development of clean energy alternatives. The Opposition has vowed to repeal and reverse the measures taken by government and warned business not to comply with government measures when they become law. Why? According to Abbott, because they pose a threat to the economy, employment and national prosperity – though he produces no supporting evidence. In reality because of a perceived threat to the fossil fuel industries, denied by government but in fact quite true and almost certain to occur over the next 50 years – hopefully sooner. For their part, proponents of the Australian scheme point to the billions raised by pricing carbon, earmarked for investment in new technology, clean energy and its improved delivery. They point to new employment opportunities which will be created and the economic advantage accruing from early adoption of clean energy compared with trading partners (eg. China, Japan, Korea, India etc) who are slow to abandon fossil fuels.
72119. Bob Lacatena at 10:46 AM on 19 October 2011
       El Niño: Unaffected by climate change in the 21st century but its impacts may be more severe
       18, adrian smits, What a bizarre site form which you've chosen to get "information." It doesn't allow comments. It claims to be "exhaustively researched, impeccably referenced" and yet I found wildly egregious errors in the first three posts I perused. It also claims to be "acclaimed by those on both sides of the global warming debate," but I find that very hard to believe. It looks like just one more wildly wrong, Cato funded denial machine to me. I would suggest that in the future you take a very skeptical eye to anything you see there... look for someone who has something else to say about it, and weigh the two positions before getting on board with take from the "World Climate Report." [Actually, from what I can see you'd be better off just avoiding the site altogether, unless you enjoy being misinformed.]
72120. Icarus at 10:43 AM on 19 October 2011
       Hansen etal hit a Climate Home Run -- in 1981
       Confidence in CO₂warming today must be... what, 99.9999%, or something? - Maybe we could say 1 in 1,744,277 chance of the warming being due to natural climate variability.
72121. Icarus at 10:28 AM on 19 October 2011
       Comparing Global Temperature Predictions
       muoncounter: Excellent! Many thanks.
72122. Stevo at 10:01 AM on 19 October 2011
       El Niño: Unaffected by climate change in the 21st century but its impacts may be more severe
       DanaHicks, thanks for the data. Okay, I think I'm starting to get a handle on this now.
72123. Bob Loblaw at 08:18 AM on 19 October 2011
       Continued Lower Atmosphere Warming
       Re. Roger Pielke @88. Well, if the data really do speak for themselves, then why do you need to say "the warming has stopped"? And just exactly what "warming" are you refering to? The warming since yesterday? Last week? No, it is the long-term statistically significant trend. If all you want to really say is "there is no accumulation of heat that time period", then say it. By making statements like "the warming has stopped", you are comparing that time period to what has come before, and making a statement about its [perhaps non-statistical] significance. You are attempting to attach importance to the data, and that implied importance is not supported by a proper statistical analysis. Basically, your claim that "the warming has stopped" is just handwaving, and your desire to "move on" appears to me to be a desire to avoid proper scientific scrutiny of your claim. It may be that in other areas of the blogosphere, a statement by Dr. Pielke that "the warming has stopped" will be accepted without skepticism and trumpeted from the rooftops, but from what I've been reading here at SkS over the past few months suggests that this isn't the place to try to get away with that. ...and trying to call it an "obvious fact" or saying "it is trivial" - as if anyone that interprets the data differently from you and comes to a different conclusion is an (-snip-) - does not seem a particularly constructive way of engaging in a dialogue.
       Response:

       [DB] I don't believe that Dr. Pielke at any point has characterized anyone with that specific, snipped, term.  Let us not descend to the verbiage used at the website RPSr defends.

72124. Rob Honeycutt at 08:12 AM on 19 October 2011
       Continued Lower Atmosphere Warming
       Dr Pielke @ 88... It seems to me that global warming has stopped before, only to come back again. Below is every 10 year trend in the UAH record. Is there a compelling reason we should expect this time to be different? [Source]
72125. Albatross at 07:37 AM on 19 October 2011
       Continued Lower Atmosphere Warming
       Bob @87, Excellent points. Despite claims to the contrary, the spin is not coming from you.
72126. Albatross at 07:35 AM on 19 October 2011
       Continued Lower Atmosphere Warming
       Hi Dr. Pielke @86, "In the mean time, can you avoid your nitpicking. :-) " I'm sorry, I was somehow of the understanding that eminent scientists should be held to a higher standard, and that getting the facts right is what we scientists strive to do. Silly me :) Some, not I, might even go so far as to post a picture of Pinnochio in association with someone's name because they were perceived to be in error ;) The nice things about blogs Dr. Pielke, is that it is much easier to make corrections or post updates than it is to get a corrigendum published. I'm sure that readers here are looking forward to seeing you correct the record on your blog regarding 1) The 1998 start date, 2) The relative contribution of CO2 and 3) The claim about OHC. You have posted updates in the past on your blog, so doing so is not without precedent. PS: I have responded to your claims about OHC here.
       Moderator Response: fixed link
72127. Albatross at 07:33 AM on 19 October 2011
       Pielke Sr. and SkS Disagreements and Open Questions
       Dr. Pielke, The amount of heat accumulated in the top 700 m varied by the team processing the data, and one is dealing with a very short window of time, so we should be very cautious about drawing sweeping conclusions or making generalizations. You seem to be making the same error with the OHC data as you are with the RSS data--drawing conclusions that are not justified by the data, or more specifically, the shorty time frame involved. For what it is worth, the accumulated heat since 2003 using the data of Palmer et al. is actually slightly higher than what you estimated using Hansen et al.'s (2005) estimate-- time will tell which analysis is more reliable.
72128. Bob Lacatena at 07:26 AM on 19 October 2011
       Comparing Global Temperature Predictions
       16, muon, The 2010 post to which you refer should be added to the Lessons from Predictions button search results.
72129. pielkesr at 07:25 AM on 19 October 2011
       Continued Lower Atmosphere Warming
       Bob Loblaw - You can keep seeking to spin, but the data do speak for themselves. If, for example, there are no more Joules in the climate system after one year, the heating (in terms of an annual average) there is no accumulation of heat that time period. It says nothing about the long term trend, but it certainly not "noise" as long as the measurements are robust. Statistical uncertainty can be placed around the actual value, as Josh Willis did. If you cannot agree to this obvious fact, I am sure others who read this weblog will. Time to move on.
       Response:

       [DB] "If, for example, there are no more Joules in the climate system after one year"

       Straw man.  In the absence of any significance testing, which you adamently refuse to do, a time series of just one year is meaningless.  Therefore any conclusions (those comments/inferences you persist in making) which follow are also without meaning; a noise in the wind.

       The science moves on to things of substance; your persistence in prosecuting this meme speaks volumes.

72130. muoncounter at 07:15 AM on 19 October 2011
       Comparing Global Temperature Predictions
       Icarus#15: "Hansen's 1981 projections" Did it way back here.
72131. DSL at 07:08 AM on 19 October 2011
       Understanding climate denial
       Steven Sherwood has a piece in this month's Physics Today comparing climate science denial with "inconvenient truths" of the past. The comment stream is, of course, filled with unevidenced silliness.
72132. Icarus at 07:06 AM on 19 October 2011
       Comparing Global Temperature Predictions
       How about Hansen's 1981 projections? - Unfortunately I'm not up to the task of adjusting these projections according to how emissions have actually panned out in the last 30 years, but it seems to me that Hansen did pretty well even that long ago.
72133. Bob Loblaw at 06:00 AM on 19 October 2011
       Continued Lower Atmosphere Warming
       In addition to Dikran's description of the Scientific Method in #79, I think it is helpful to keep in mind that when writing about scientific work, it is fundamentally important to distinguish between observation, interpretation, and conclusion. In terms of something statistical, the data are observations, the regression is an interpretation of the data, but to draw conclusions pretty much requires some sort of significance testing. In Dr. Pielke's comment #69, he says

       First, I am NOT saying anything about the effect of the lack of warming in the global-annual average surface temperature since 2002 or 1999 (or whatever start year) on the long term trend. I agree it is too short of a record. However, it is trivial in my view (and does not need any statistical evaluation) to see that the warming has halted,

       ...so that although he admits that the time period is too short for significance testing, he is going to go ahead and draw a conclusion anyway. The phrase "the warming has halted", is not an observation. It is not an interpretation. It is a conclusion. An unjustified (and in this case, unjustifiable) conclusion. Dr. Pielke is trying to say something, and he appears to be wanting to be able to say it even though he knows there is no significance testing to back it up.
72134. pielkesr at 05:59 AM on 19 October 2011
       Continued Lower Atmosphere Warming
       Hi Albatross "Additionally, you initially claimed on your blog that there has been zero accumulation of heat in the upper 700 m of the oceans since the beginning of 2003 (that error is still present on your blog for all to see), not "limited warming" since 2004. I am, sadly, beginning to have serious doubts that you are interesting in discussing the science in good faith." You should date when I made these statements. In the figure in Pielke Sr., R.A., 2008: A broader view of the role of humans in the climate system. Physics Today, 61, Vol. 11, 54-55. http://pielkeclimatesci.files.wordpress.com/2009/10/r-334.pdf provided by Josh Willis, there was no warming, averaged over a year using his best estimate of the mean (with uncertainties shown). In 2011, the plot http://www.nodc.noaa.gov/OC5/3M_HEAT_CONTENT/, the plot is still ~flat since ~2003. However, on SkS, data has been shown that has some warming in the upper oceans. In order to be inclusive of your view and that of others at SkS, more recently, I wrote (and presented at my Waterloo talk) that there has been some warming. In any measure, however, it is well below what the models predict in terms of the long term accumulation. I see in the SkS post bt Rob Painting that it is expected to resume at a higher rate. This is a good test of the models and time will tell. In the mean time, can you avoid your nitpicking. :-)
72135. CBDunkerson at 05:16 AM on 19 October 2011
       SkS Weekly Digest #20
       Gotta disagree with you there John. The 'false equivalence' bit is what most of the media does. Fox, on the other hand, gives you your choice of multiple clueless blowhards.
72136. John Hartz at 05:13 AM on 19 October 2011
       SkS Weekly Digest #20
       Lest there be any confusion, the above Toon of the Week satirizes how Fox News and other like media outlets perpetuate the myth of scientific debate by giving equal weight to the findings of legitimate scientists and the opinions of non-scientists. The fact that the couch potato in the toon is named "Roger" has absolutely nothing to do with Dr. Roger Pielke Sr., a distinguished scientist.
72137. jg at 03:43 AM on 19 October 2011
       Comparing Global Temperature Predictions
       Bern, I will work on a variation of the animation that includes your suggestion. jg
72138. muoncounter at 03:43 AM on 19 October 2011
       Continued Lower Atmosphere Warming
       DM#82: "it is incorrect to assert that one trend IS different from another unless the difference in trends is statistically significant." Could not agree more with that statement. This is essentially a signal processing problem, that of extracting meaningful changes in trends from noise. As such, this working definition of statistical significance is relevant: Statistical significance can be considered to be the confidence one has in a given result. In a comparison study, it is dependent on the relative difference between the groups compared, the amount of measurement and the noise associated with the measurement. In other words, the confidence one has in a given result being non-random (i.e. it is not a consequence of chance) depends on the signal-to-noise ratio (SNR) and the sample size. If we cannot establish the significance of the supposed change in trend, then how can we say that we are confident in its existence? And if we are not confident in its existence, how can we base any conclusion on it?
72139. JMurphy at 03:07 AM on 19 October 2011
       OA not OK part 20: SUMMARY 2/2
       With regard to the Erl Happ fiasco (as mentioned by Philippe Chantreau), I think the result for WUWT was even more of a joke because Erl Happ seemed to suggest (in a tongue-in-cheek manner) that the cock-up might have been due to one of three possibilities : one of which being that he may have written it after having drunk a glass of wine. I can't remember the exact details (and I can't bare to return to WUWT to check - you have to wade through so much treacle to find what you want), but Watts used that supposed admission of drunkenness as a get-out clause to blame it all on the author, and to try to scrape back some credibility by banning Erl Happ from posting any more pieces. First Goddard, now Happ - how many more before even Watts's friends admit the denial-reality of his website ?
72140. Alexandre at 02:55 AM on 19 October 2011
       How Increasing Carbon Dioxide Heats The Ocean
       Harald Korneliussen at 22:10 PM on 18 October, 2011 There's an interesting series about this subject on ScienceOfDoom, beginning here: Does Back-Radiation “Heat” the Ocean? – Part One At some point into the series he explores some simple models to help understand the role of the upper turbulent layer you mentioned, that yes, also plays its role.
72141. Anne-Marie Blackburn at 02:44 AM on 19 October 2011
       How Increasing Carbon Dioxide Heats The Ocean
       Excellent post, Rob. Off to learn more about it.
72142. Albatross at 02:31 AM on 19 October 2011
       Continued Lower Atmosphere Warming
       Hello Dr. Pielke @77, "What I have reported on is the limited warming in the upper oceans in recent years (since 2004) which is clearly evident in http://oceans.pmel.noaa.gov/. If you (and the others) want to ignore the obvious you certainly can do that. " This is now getting very annoying Dr. Pielke. You may not realize it but you are making strawmen arguments. Also, I urge you (again) to please stop misrepresenting our position (this time on OHC) and going off topic. Anyone following our discussion with you knows that what you said above about us "ignoring the obvious" is simply not true. Additionally, you initially claimed on your blog that there has been zero accumulation of heat in the upper 700 m of the oceans since the beginning of 2003 (that error is still present on your blog for all to see), not "limited warming" since 2004. I am, sadly, beginning to have serious doubts that you are interesting in discussing the science in good faith.
72143. Philippe Chantreau at 02:29 AM on 19 October 2011
       OA not OK part 20: SUMMARY 2/2
       Funny how Watts uses a study that seems at first glance rather well done and then tries to argue for the opposite of what the study suggests. I note that he uses the term "weasel words" to qualify terminology used in the paper to communicate uncertainty. I wonder how Dr Pielke, for instance, would react to such vocabulary employed here. Funnily enough, "skeptics" have a habit of complaining that uncertainty is not plainly revealed in the litterature. Oh well. Compared to the recent Erl Happ fiasco, in which he was scolded by contributors for his gross igorance, and by Watts, for writing posts while drunk (and bragging about it), this one is rather tame. Voted best science blog, mind you.
72144. Dikran Marsupial at 02:11 AM on 19 October 2011
       Continued Lower Atmosphere Warming
       Eric (skeptic) I wouldn't agree or disagree, because without investigating the data I simply don't know. Fortunately there are methods for estimating the statistical power of a test, which can address such issues (although of course you also need to perform the test in collaboration with domain experts so you know what the issues are so the analysis is based on appropriate assumptions).
72145. Dikran Marsupial at 01:40 AM on 19 October 2011
       Continued Lower Atmosphere Warming
       pielkesr The problem with your revised statement is that it is incorrect to assert that one trend IS different from another unless the difference in trends is statistically significant. This is because the trend is a statistic that is only estimated from data, we don't know the true value of the trend, the best we can do is to compute a confidence interval that is indicative of the uncertainty of the estimate (loosely speaking if it is a frequentist confidence interval). So to assert that the trends actually are different you need to establish that the uncertainty in the estimation of the trends is sufficiently small that we can be confident that a difference actually exists. As for how long we need, the estimate of 17 years given by Santer et al sounds reasonable, and is consistent with other studies I have seen, though I haven't performed the calculation myself. In the case of your third hypothesis though, you only need to show that the difference is statistically significant, and don't need to consider the power of the test so much as you are arguing against the null hypothesis (the actual trends are the same). There is a complication due to the choice of the start point, but that is a finer point. We could perhaps agree that there was a difference in the estimated trends from 1979-2002 and 2002-2011, but that the difference was statistically insignificant, but that is a pretty bland statement and couldn't be used to support any statement about the climate.
72146. barry1487 at 01:29 AM on 19 October 2011
       How Increasing Carbon Dioxide Heats The Ocean
       Rob, thanks for this post. It's a bit of a missing link for lay people, I think. When you know that the average temperature of the ocean is warmer than that of the atmosphere, and that heat flows from a warmer body to a cooler one, the idea that a warming atmosphere can warm the oceans is not straightforwardly intuitive. You've clarified it well. Still have questions, though. When you say,

       "Indeed, climate models suggest that ocean warming will continue for at least a thousand years even if CO2 emissions were to completely stop."

       It makes me wonder why equilibrium is considered to be reached after 30 - 40 years of oceanic lag, rather than 1000. Why is the long tail not included in equilibrium climate sensitivity?
72147. Eric (skeptic) at 01:28 AM on 19 October 2011
       Continued Lower Atmosphere Warming
       Dikran, would you agree (or disagree) that the period required for statistical significance of a change in trend is shorter for ocean heat content than it is for GAT? IMO, it would be shorter for the reason that OHC is affected by fewer modes of natural variability than GAT, particularly the decadal ocean atmosphere cycles or quasi-cycles.
72148. pielkesr at 01:20 AM on 19 October 2011
       Continued Lower Atmosphere Warming
       Dikran Marsupial - Perhaps this will clarify, change "the trends during this time period [2002-present] are different than the trends earlier in the time period [1979-2002]." to "the 9 YEAR TREND during this time period [2002-present] IS different than the TREND FOR the time period [1979-2002]. THIS SHORT TERM TREND DIFFERENCE IS NOT LONG ENOUGH TO CONCLUDE THAT THE LONGER TERM TREND HAS BEEN CHANGED. HOWEVER, IT DOES PROVIDE US WITH A METRIC TO FOLLOW IN ORDER TO SEE HOW LONG THIS DIFFERENT TREND WOULD HAVE TO CONTINUE BEFORE WE CAN CONCLUDE THE LONGER TERM TREND HAS CHANGED IN TERMS OF STATISTICAL SIGNIFICANCE." Now, you are more of a statistics expert than I. Please tell us how many more years of the 2002 to 2011 trend would have to continue before one could conclude the long term trend has changed. This would be a diagnostic that both the SkS readers and the "skeptics" would agree on.
       Moderator Response: [Albatross] Please avoid using all CAPS. Thanks.
72149. adrian smits at 01:15 AM on 19 October 2011
       El Niño: Unaffected by climate change in the 21st century but its impacts may be more severe
       http://www.worldclimatereport.com/index.php/2011/10/17/no-change-in-storminess/ It would appear your press release has been trumped by peer reviewed scientific literature that has studied storm intensity over the last 5000 years with no indication of major change in storm intensity or quantity!
       Response:

       [DB] Actually, it would appear that your blog source inappropriately conflates:

       • a study of Holocene intense hurricane strikes in parts of the Gulf of Mexico (essentially local/regional conditions found during a time dissimilar to those expected during the 21st Century for the globe as a whole)
       • a study of extreme value statistics under modeled North Atlantic cyclones during winter conditions vs those in a warmer climate (again, a regional study; the primary finding was that in a warmer climate there was a more northern track followed by the cyclones; conclusions beyond that not possible due to the need for a larger sample size)

       So you would have readers here believe that a study looking at past, localized conditions in the Gulf of Mexico and another study of North Atlantic cyclone extreme value statistics (both with afore-detailed limitations) rule out future, global expected changes as detailed in the OP.  Seriously?

       A prudent "skeptic" would take the time to actually read the referenced studies for themselves before swallowing disinformation hook, line and sinker.

72150. Kevin C at 00:52 AM on 19 October 2011
       Lindzen Illusion #2: Lindzen vs. Hansen - the Sleek Veneer of the 1980s
       Oh yes, I see your point. (And I think you can also see how Charlie and I reached our conclusion?) Given the Lindzen's counterfactual picture of the temperature record, I guess Dana's line is as good as any. Sadly that's not a very satisfying criteria. I suppose presenting an ensemble of possible lines with Lindzen's gradient on the whole record might be more realistic, but that's ugly and arguably misleading too (and wouldn't fit on the graph for the new article). OK, I give up.

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