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Comments 124151 to 124200:

124151. CBDunkerson at 00:12 AM on 17 February 2010
        Did Phil Jones really say global warming ended in 1995?
        John/40 Shades, without doing the full statistical analysis we can still use past variability as a general guide. For instance, there was a 30 year 'pause' of mild cooling in the warming trend from ~1940-1970. Thus, the current 15 year period of only mild warming doesn't seem particularly anomalous. For me, it'd have to run more than 30 years (say 40) without warming passing 95% certainty to 'give pause'. That hasn't happened before in the instrumental record so it would indicate something 'new'. Anything shorter than that is just consistent with past variations.
124152. John Russell at 23:58 PM on 16 February 2010
        Did Phil Jones really say global warming ended in 1995?
        Ricardo @31 I think you missed the point of '40 Shades of Green's' question. He's (she's?)asking if someone with the required knowledge has done the statistical analysis on the actual data, and what the result was? A fair question I would say. As a lay response I would say there's no magic level of data that must reveal a trend hidden in noise. Imagine looking at a newspaper photograph at a high level of magnification under a microscope: with a few dozen dots (data) visible you wouldn't have a clue what the picture was about. Now reduce the magnification. At a certain point -- and number of dots (data) -- one can start to make out the image and have a stab at what's being revealed. The lower the magnification, the more dots (data) and the more certain you can be of what you're looking at. I hope that helps.
124153. CBDunkerson at 23:42 PM on 16 February 2010
        Did Phil Jones really say global warming ended in 1995?
        I just noticed something odd about the OHC chart. A frequently raised topic in AGW discussions is 'natural variability', particularly as it relates to cycles of oceanic heat transfer. The 'pacific decadal oscillation' (PDO) seems to be a particular favorite. Basically, the theory is that cyclical circulation of colder deep ocean water and warmer surface waters has a strong impact on climate. So, if the PDO, as one of the larger cycles observed, is pushing alot of cold water to the surface that is going to have a cooling effect on the atmosphere. Such is often used to explain cooling trends from 1880-1910 and 1940-1970. Then the cycle reverses and ocean heat is transferred to the atmosphere, causing warming. However, looking at the OHC graph it seems like there was a drop from 1960-1970... the same time the ocean was supposedly 'sucking up heat' from the atmosphere. Then from 1970-2000, when the ocean was supposed to be releasing heat into the atmosphere, OHC went through the roof. Does this disprove oceanic heat transfer as a major driver of climate? I suppose greenhouse warming could have overwhelmed ocean cooling from 1970-2000, but why did ocean heat decline from 1960-1970? Was there a solar decline in that timeframe which would explain both the atmospheric and oceanic heat declines?
124154. Marcus at 22:42 PM on 16 February 2010
        Did Phil Jones really say global warming ended in 1995?
        Sorry, Arkadiusz Semczyszak, but your claims are not borne out by the numbers. Consider the last 90 years, in 30 year increments: 1920-1949, 1950-1979 & 1980-2009. For 1920-1949, average monthly sunspot numbers increased by around 2.5 per year, & temperatures rose at an average of 0.0095 degrees per year during that time. For 1950-1979, average monthly sunspot numbers decreased at a rate of 0.5 per year (which is almost nothing at all), and temperatures rose at around 0.0016 degrees per year (which is also almost nothing at all). For 1980-2009, sunspot numbers declined an average of 2.7 per year, yet temperatures during that period rose by 0.016 degrees per year. So we are in fact seeing the fastest 30-year rise in global temperatures, this century, at a time when we're also seeing the most rapid 30-year decline in sunspot numbers this century. I can't see how that fits with an "its the sun" theory. One final point, though not statistically significant, temperatures rose by 0.012 degrees per year between 2000 & 2009, yet average sunspot numbers fell by around 14.5 per year.
124155. ScaredAmoeba at 21:32 PM on 16 February 2010
        The Dunning-Kruger effect and the climate debate
        JonMoseley @ 69 You ask: 'Is the Earth's plant life capable of absorbing more CO2 than it currently does? Has the Earth's plant life reached a maximum cap, beyond which it cannot absorb any more CO2?' Well, as we know that atmospheric CO2 is rising and has been rising since the Industrial Revolution, it would seem that the answer is yes! And we know that the ocean has been absorbing around 50% of the carbon emitted. Rising temperatures aren't going to make things any easier either. There are a number of temperature-sensitive carbon sinks that are expected to to become carbon sources as temperatures increase. You also state: 'Just as increasing sugar as food to a culture will stimulate growth, it is reckless to ignore the effect of the Earth's plant life reacting dynamically to an increased presence of CO2.' Yes this is true, but as ideas go it is half-baked. Can you point to CO2 starvation ever being a growth limiting factor in the open air? [Citations from reputable journals only, please.] Now I can fully guarantee that this is only a partially-baked answer, but what do you expect in a blog post? The over simplistic relationship between plants and CO2 is often raised as one of those: 'CO2 isn't universally bad, it will result in more plant growth' arguments [so beloved of the Denial Industry, who just seek to confuse the public], but this is an area which has revealed a number of genuine surprises. Free Air CO2 Enrichment studies reveal that the effects of enclosures that were used in many previous studies typically overwhelmed the CO2 enrichment effect. Now I realise that this isn't the same as what you were aiming at, but it reveals that studies that suggested CO2 led to increased plant growth need to be reassessed since their findings may be an artifact of the test method. There are an increasing number of studies that show unforeseen effects of increase CO2 levels: Growth and nutritive value of cassava (Manihot esculenta Cranz.) are reduced when grown in elevated CO2 RoslynM.Gleadow 1, John R. Evans2, Stephanie McCaffery2 & Timothy R. Cavagnaro2,3 Plant Biology ISSN 1435-8603http://www.biolsci.monash.edu.au/staff/gleadow/docs/gleadow-2009-cassava-online.pdf Changes in Nutritional Value of Cyanogenic Trifolium repens Grown at Elevated Atmospheric CO2 RoslynM.Gleadow & Everard J.Edwards & John R. Evans J Chem Ecol (2009) 35:476–478 DOI 10.1007/s10886-009-9617-5http://www.biolsci.monash.edu.au/staff/gleadow/docs/2009-clover-cg-co2.pdf Food for Thought: Lower-Than Expected Crop Yield Stimulation with Rising CO2 Concentrations http://www.bnl.gov/face/pdfs/Long_2006.pdf "Climate Change Surprise: High Carbon Dioxide Levels Can Retard Plant Growth, Study Reveals ScienceDaily (Dec. 6, 2002) http://www.sciencedaily.com/releases/2002/12/021206075233.htm Nine further studies here: http://www.logicalscience.com/skeptic_arguments/CO2-fertilization.html Therefore the answer to: 'Just as increasing sugar as food to a culture will stimulate growth, it is reckless to ignore the effect of the Earth's plant life reacting dynamically to an increased presence of CO2.' is: It is reasonable to expect wild plants to respond in a variety of different ways, and not necessarily in a manner beneficial to human society or the ecosystems where the plants belong. Yes it is reckless to expect the biosphere to respond in a manner that will reduce our obligation to cease our destructive behaviour. Yes increasing atmospheric CO2 will affect ecosystems, but their response cannot easily be predicted and surprises are likely. Yes we should be cautious about large scale tampering with the energy budget of the earth, it may not be beneficial to us, the climate or other life on Earth.
124156. Riccardo at 21:14 PM on 16 February 2010
        Did Phil Jones really say global warming ended in 1995?
        40 Shades of Green, there's no a priori time span. You need to perform statistical analysis on the actual data and determine it. Here's a draft of Von Shuckman et al. 2009..
124157. John Russell at 20:41 PM on 16 February 2010
        Did Phil Jones really say global warming ended in 1995?
        To revert to my analogy posted under another topic. It's like watching the last 14 waves that came in on the beach and trying to work out whether the tide is coming in or out. The variation in height of the last 14 waves does not give one enough information to produce a statistically significant trend (even less so the last 8 waves). The noise (waves) hides the trend (tide). After ten minutes and a hundred waves the direction of the tide becomes very apparent. I wonder why Phil Jones didn't think to use such a clear analogy? The lay audience would have got it in one and those with a basic scientific understanding would/could not have questioned the way he expressed himself.
124158. 40 Shades of Green at 20:37 PM on 16 February 2010
        Did Phil Jones really say global warming ended in 1995?
        To my mind the key question is this. If 15 years without statistically significant warming is not enough to give one pause, then how many years would be required. 20, 25, 30, 50, 100?
124159. 40 Shades of Green at 20:31 PM on 16 February 2010
        Did Phil Jones really say global warming ended in 1995?
        Hi Would you have a link to either a Non Paywall version or a discussion of either or both of Murphy 2009 and Von Schuckman 2009. Many thanks 40 Shades
124160. Dikran Marsupial at 20:26 PM on 16 February 2010
        Did Phil Jones really say global warming ended in 1995?
        Jon Moseley said: "To be valid science, one must state that a measurement that is not statistically significant is equivalent to ZERO." The thing to remember about statistical tests is that "absence of evidence is not evidence of absence". If you treat the trend as equivalent to zero you are saying that the lack of statistically significant evidence for a positive trend is evidence that the trend is zero, which is not correct. This is precisely the assumption you make when you criticized the models "Furthermore, the observed results are in conflict with the predictions of the computer models." For there to be a model-data conflict, the error bars of the observed trends need to be outside the spread of the modelled trends. If you did the comparison properly there is no conflict.
124161. MarkR at 20:23 PM on 16 February 2010
        Did Phil Jones really say global warming ended in 1995?
        jasonk: The reason a shorter time frame is less statistically significant for the same trend is that noise tends to average to zero at longer time scales. this also demonstrates the effect. Also, it's less likely that noise will always 'add up' to a trend over 20 years than it will do so for a shorter time period. If you think of it as flipping a coin each time with heads meaning noise goes warmer, tails cooler, then it's clearly less likely and you can claim higher statistical significance. As for +0.12 -0.12 = 0, that's not how it works in trends. If you take 1995-2009 you get +0.12K/dec and this includes the 'cooling' period from 2002. It just so happens that 1995-2002 is a trend of +0.26K/decade. And you can't add trends anyway unless they're for equal time periods. Eg if you raise temperatures at +0.2C/decade for 50 years you end up 1C warmer than you were before. If you then cool at 0.2C/decade for 10 years, you'll only cool by 0.2C and you'll still be 0.8C warmer than you were 60yrs ago. The 60 year trend will remain positive, even though +0.2 - 0.2 = 0.
124162. MarkR at 20:12 PM on 16 February 2010
        Did Phil Jones really say global warming ended in 1995?
        JonMosely: do you have a reference for that claim so I can check? As I understand it, your precision may be near perfect, but the system may be intrinsically 'noisy' (eg El Nino is a real physical phenomenon, but in the context of looking for warming it contributes to 'noise'). So your precision may be enough to detect a trend, but without knowing how to fully account for all of the noise, you must treat it as such and determine based on the known high frequency noise in the data whether it is statistically significant or not. So Jones is right; there is a trend, but there is a 5%+ chance that it could have occurred from noise. Which is unsurprising, given that an ENSO switch is 0.4-0.7C in a few months and 'global warming' is a trend of 0.1-0.2C/decade atm and so people tend to talk about longer time periods. Please correct me if I'm wrong and point me towards where I can fix my understanding.
124163. Dikran Marsupial at 20:01 PM on 16 February 2010
        Did Phil Jones really say global warming ended in 1995?
        JonMoseley says: "Any measured change or trend that is not statistically significant DOES NOT EXIST scientifically." No, that is incorrect (but a very common fallacy). If a measurement is not statistically significant it means there is insufficient evidence to reject the null hypothesis. In this case it means the trend is too small (w.r.t. the noise) to be confident that the trend is not zero. That is not at all the same thing as "the trend does not exist scientifically". Of course one would not build an argument solely on a non-statistically significant trend, but then again AGW theory has a much broader base of evidence and nobody (who understands statistics) would claim that a short term trend is proof of AGW. "Furthermore, the observed results are in conflict with the predictions of the computer models. Therefore, the computer models are wrong." Actually that is not correct either, see the paper by Easterling and Wehner, which shows that the internal variability of the climate means that there will be occasional decadal trends showing no warming or even cooling, and that these are seen in the output of the models. http://www.agu.org/pubs/crossref/2009/2009GL037810.shtml A common demonstration of the Dunning-Kruger effect in discussions of climate is a lack of understanding of what the models actually say.
124164. HumanityRules at 19:54 PM on 16 February 2010
        The Dunning-Kruger effect and the climate debate
        Chris #57 I did read the whole article, John started each small section with a skeptic question (quotes and italics). All very simplified but the question of uncertainty and poor understanding of some systems still needs to be raised. Based on the examples John raises. 1) CO2 - Few believe that CO2 levels aren't rising in the atmosphere yet there does appear a case for what that means for future climate and maybe more importantly it's impact on society going forward. Many of the non-peer reviewed source issues with the IPCC seem to focus on this later aspect. 2) Solar - Just from John's list of papers solar seems to have contributed between -1.3% to 50% of 20th century warming. Scope for improvement there. IPCC seem to go with negligable affect. There are other solar scientists that take a different approach such as Friis-Christensen and Henrik Svensmark. That solar breaks down some the present period is as true as CO2 and temp break down 1940-1970. The climate is a complex thing. 3) Paleoclimatology - Methods and conclusions have been critised in both blogs and peer-reviewed papers. And it appears the IPCC presentation of this shows signs of political (with a little 'p') interference. You have to question throwing away 75%+ of your data to come to a 'desired' conclusion. "Question everything"
124165. Arkadiusz Semczyszak at 19:49 PM on 16 February 2010
        Did Phil Jones really say global warming ended in 1995?
        1. "No Comments" may be used at most trends: 70 + / - 10 years x n. They include most cycles: Gleissberg's; AMO+PDO, THC, EN(LA)SO. 2. Marcus repeats: the sun "expire" ... and the warming continues. However, the present warming is consistent with the millennium cycle. I recall a diagram: http://www.rni.helsinki.fi/research/info/sizer/fig2big.jpg; and I am adding a new: http://mclean.ch/climate/figures/GISP_to_4Kbp.gif. Present Warming is greater in NH than the SH. Rahmstorf has repeatedly said, that the Millennium cycle is dependent on the cycles of the sun - but not directly. So far, created a few theories to explain this relationship.
124166. Riccardo at 19:09 PM on 16 February 2010
        Working out future sea level rise from the past
        JonMoseley #86 i'm a bit confused. Are you claiming that sea level falls in a warmer world and rises during colder ages? Are you saying that in Antarctica there's not ice melting in summer? It seems to strongly contradict the evidence ...
124167. Arkadiusz Semczyszak at 19:09 PM on 16 February 2010
        Did Phil Jones really say global warming ended in 1995?
        Using the trend from 1995 - 2009 without the commentary is wrong. Because it covers the end of the transition from the cold phase in the warm AMO, which is always sharp. In turn, it is wrong to use the 1998-2009 trend - without taking into account the impact of EN(LA)SO.
124168. Riccardo at 19:04 PM on 16 February 2010
        Working out future sea level rise from the past
        JonMoseley, do you think you've just discovered the concept of center of mass? Do you think that people here (let alone the climatologists) do not know about it? Come on ...
124169. Riccardo at 18:59 PM on 16 February 2010
        Did Phil Jones really say global warming ended in 1995?
        The question asked by the BBC journalist had clearly the intention to be equivocal. Indeed, 1995 is the last year for which there is not a statistical significant trend. It's easy to make a trend not statistically significant, just make it short enough, but it can not disprove (nor prove) anything. If you want to clarify the recent apparent slow down of temperature increase a better question would be: "is the recent (apparent) slow down of the temperature increase statistically compatible with the long term trend?" The answer is a sound yes.
124170. Steve L at 18:25 PM on 16 February 2010
        Did Phil Jones really say global warming ended in 1995?
        Re #14, mazibuko -- good points. You might add that power analyses should be employed when trying to determine an appropriate choice of alpha prior to hypothesis testing. Hmmm, I can't find the reference I want right now. Here Tamino has some information on the amount of noise versus signal to expect for these kinds of tests. Another consideration is the issue of whether or not one is testing a one-tailed or two-tailed null hypothesis. The link above (hopefully it works) shows a two-tailed confidence interval. I don't know if Jones' test was one- or two-tailed, but really it should have been one-tailed. A one-tailed test is more powerful (more able to reject the null hypothesis). Almost finally, independent from the issue of signal versus noise, there is the issue of what's special about 15 years for this particular test. Hypothesis testing requires that the test be constructed a priori. It's invalid to watch as data are added, going forward in time, and then to make simple conclusions (ignoring the non-independent tests that have already occurred) when a calculated p-value finally goes above or below 0.05. That is, you can't cherry-pick the time frame. Finally, JonMoseley in #3 might do well to construct another hypothesis test: Ho = the rate of warming does not differ significantly from a rate of 0.2 C/decade. Failing to find significance there means, if you apply Moseley's funny interpretations of statistical rules, that differences with consensus expectations of AGW do not exist.
124171. CBDunkerson at 18:18 PM on 16 February 2010
        Is CO2 a pollutant?
        JonMoseley, there is actually rather alot of science proving that CO2 warms the Earth's atmosphere... even outside of laboratories. Several examples can be found here. As to your convection hypothesis... it fails because, amongst other things, greenhouse gases do not retain heat within themselves. They absorb and then immediately re-emit the infrared radiation. Since this energy is re-emitted in an essentially random direction this means that some of the infrared radiation traveling from the Earth's surface up and out into space is instead reflected back down to the planet by greenhouse gases. If you refer back to the link above you will see that it includes direct evidence of this absorption and re-emission in that radiation escaping the atmosphere shows a reduction in the wavelengths absorbed by carbon dioxide while radiation coming down from the atmosphere shows an increase in those same wavelengths.
124172. Bern at 18:09 PM on 16 February 2010
        Did Phil Jones really say global warming ended in 1995?
        John, is it possible to include a chart showing the estimated cooling/warming rate for the two periods (1995-2009 & 2002-2009) along with the error range for each? I think that might be educational. Not sure how to represent it, though - perhaps a column chart showing the upper & lower bounds of the uncertainty interval for 90 & 95% confidence, and the nominal rate in the middle? (Don't know if you have the data for that, though)
        Response: I was mulling whether to do a follow-up post on statistical significance over different periods - I may do one tomorrow. I do have the data for that. Thanks for the suggestion.
124173. Jeff Freymueller at 17:54 PM on 16 February 2010
        Did Phil Jones really say global warming ended in 1995?
        #10, hallewis. Jones did not say what you seem to think he said. Please reread: "Achieving statistical significance in scientific terms is much more likely for longer periods, and much less likely for shorter periods." This is a general statement, and completely true, because the uncertainty in the rate will be higher for shorter periods. He did not make any claim about what the significance for 2002- beyond 2009 would be if there were more data recorded. But if you took earlier data, say 1980-2009, then the data would show a warming trend at a very high level of confidence, easily surpassing the 95% confidence level that is usually used.
124174. Jeff Freymueller at 17:48 PM on 16 February 2010
        Did Phil Jones really say global warming ended in 1995?
        #6 jasonk, part of the reason for your confusion is that neither of the rate estimates include the uncertainty. Estimates should always include the uncertainty -- that's the only way you know how good the estimate is. The uncertainty is half of the answer. In this case, the uncertainty in the 2002-2009 rate would be about 2-3 times as large as the uncertainty in the 1995-2009 rate, depending on the noise characteristics of the data. The larger the uncertainty, the lower the confidence level that the estimate is significantly different from zero.
124175. Satin9 at 17:44 PM on 16 February 2010
        The Dunning-Kruger effect and the climate debate
        #69 Look up the FACE experiments. You will note that yes trees will grow more rapidly with higher CO2 concentrations. In the US phase of the work fast growing lobolly pines were used which accounted for the improved growth rate (15%). However, carbon loss from rapid breakdown by microorganisms of leaves bark etc offsets some of the savings of CO2 in timber. Also CO2 is not the only factor for growth. Other limits to growth have been noted such as nitrogen and phosphorus which will also set a limit how much and how fast vegetation can grow.The experiment when carried out in established forests produces no change in growth. Also in your posts on CO2 levels. With respect to your posts on measuring CO2. Before the CO2 measuring station was established in Hawaii, the scientist responsible for the work Keeling the elder traipsed around the USA for 2 years measuring CO2 levels at many locations. He found that in spite of previous assertions that CO2 concentration would vary...in fact they did not. He also found that there was a diurnal variation in CO2 levels. Lower in the day and higher at night...plants breathing in and out. Later studies also showed that there were seasonal variations in CO2...higher in summer, lower in winter.The continuous measurements of CO2 in Hawaii started by Keeling in 1956 show a year by year increase in CO2. Also note that Hawaii is not the only place where measurements are taken but it has the longest historical record of data. The other aspect of CO2 levels is that the level of carbon 14 in the atmosphere has declined as fossil fuels are burnt...they consist of carbon 12 only the carbon 14 has decayed away over the millions of years it has been locked away. You need to keep an open mind. The risks and costs of unpredictable climate change associated with AGW even in the mildest predictions of the IPCC are large and will be felt by those least able to afford the adaptations that may be required. So we have a moral duty to look at the science seriously...skepticism is fine but dismsiing obseravtions and facts collected and established over 50+ years is ethically unsound.
124176. Bern at 17:37 PM on 16 February 2010
        The Dunning-Kruger effect and the climate debate
        JonMosely @ #68: Er, did you actually read my entire comment? All of it? And think about what I wrote? I'll quote this bit: "Actually, when you look at it, even *that* carbon is sourced from nature" We're all aware, here, that the carbon in fossil fuels originally came from nature. The problem, as I tried to explain, is that we are fiddling with nature. The 'equilibrium' state of the Earth has a certain amount of that carbon 'in circulation', as it were, that is released & absorbed continually in plant growth, decay, animal activity, etc. The rest is sequestered in coal & oil deposits, methane hydrates, and numerous other ways (I wont pretend to know all the details). There's probably an enormous amount buried deep in the crust, and even more down in the mantle. Human industrialisation (specifically, the burning of fossil fuels) is upsetting that balance by taking large amounts of that sequestered carbon and dumping it into the atmosphere. We're talking about truly enormous amounts of carbon, here - enough to increase the amount of CO2 in the atmosphere by more than a third, *despite* the rate of absorption by plants & oceans increasing with the concentration. And we're doing it in a time-frame that, on a geological scale, is virtually instantaneous. The consequences of that might be very unpleasant for human civilisation and many species of plants & animals, though I'm sure others will thrive. Actually, the references by others to the Carboniferous Era prompted me to look it up. Wikipedia suggests that sea levels during that era were up to 80-120m higher than present levels. Hmm. I hope you don't live near the sea...
124177. stevecarsonr at 17:26 PM on 16 February 2010
        Did Phil Jones really say global warming ended in 1995?
        - #15 bigelowe: The global temperature indices are only measuring surface temperature of land and sea. The top few mm of the ocean. So the HADCRUT, GISS, etc don't measure Energy (Let's see if html tags work..) Which is a problem because that's really what everyone is interested in (everyone in climate). Obviously surface temperature is a function of energy but in very derived and convoluted ways. For example, during ENSO events, colder water gets pushed up to the surface and we say "global temperatures have gone down". In fact, probably the total ocean energy is the same, and more likely to be going up for a few months or years because less heat is radiated out from the oceans now the surface is colder. The reverse is true. Because we only measure the surface temperature we are measuring quite a random or unpredictable variable. Especially as the oceans are 70% of surface area and therefore weighted to 70% of global temperatures. But it's hard to measure OHC (ocean heat content). I read a climate guru recently (can't remember his name) saying that they had more confidence in global temperature measurement than OHC measurement. Although he implied but didn't really say whether consequently it was more use. The Argo project now has about 3000 sensors around the oceans collecting temperature and salinity data down to 2km. They started being deployed late 90's but really have only fully been in place for a few years. And they don't measure below 2km. In the past there were lots of measurements of vertical temperature profile in the oceans done using XBTs but then someone found out that they had some biases (don't really know the story on that one) and consequently a lot of the old numbers that had been collected have issues. I think that once we have our hands around OHC much more of the climate will be understandable. This should also be the measurement that is the headline number and graphic everywhere, not the "surface temperature". Just my opinion.
124178. bigelowe at 16:19 PM on 16 February 2010
        Did Phil Jones really say global warming ended in 1995?
        John, Just so that I'm clear on this....the HADCRUT data, and the data Jones refer to, are measurements of both land and marine surface areas. The chart you have on the bottom includes energy accumulated in deeper areas of the oceans, which are not included in the other measurements. Is this correct? I was a little unclear on this point. If anyone else knows the answer, feel free to confirm. Also, what is the reason that temperature of the oceans is not included along with the rest. Is this because of inadequate monitoring, or for some other reason? Thanks,
        Response: Figures 1 and 2 are measurement of surface temperature, both land and ocean, in degrees Celsius. Figure 3 is a different metric - it's a measure of heat content, in Joules. What is the relation between surface measurements and total heat content? See the tiny red sliver in the total heat content graph? That's the portion of global warming that goes into heating land + atmosphere. Note that only part of this goes into warming the atmosphere - the energy to melt ice and heat land is also included in the red area.
124179. 70rn at 16:13 PM on 16 February 2010
        The Dunning-Kruger effect and the climate debate
        Co2s role in the metabolism and respiration is hardly unknown or unstudied. given we're discussing co2s atmospheric effects is not really pertinent to this debate. However on the oft chance your interested I suggest you examine the difference between c3, c4 and CAM metabolism and the possible effects that co2 might have. Co2s energy movments are rather complex and what your suggeting is broadly correct, the energy ultimately radiates back into space. Co2 absorption acts upon a specific range of wavelengths which it then re emits or transfers during molecular collision, end result being energy distribution. It isn't a process of trapping per sè, but one of delaying release into space. A greater of amount of co2 lowers the rate at which long wave radiation in the applpicable part of the spectrum escapes (this is observed) - which causes an imbalance as there is always more energy being inputted by the sun. The net effect is greater heat retention in the atmosphere. The effect that extra heat will have upon convection is understood, and is considered a bit of a downer actually. Pressure cells all basically operate via this mechanism, and extra heat will increase their rate of function, leading to stronger storms - greater precipation etc... Conversly this intensification will also result in longer duration droughts in applicable regions, broken by larger flooding periods. Such a process cannot be considered positive for the infrastructural, agricultural or ecological systems effected. Might need to go and play Donkey Kong on my Nintendo, I require some thoughtful entertainment.
124180. mazibuko at 15:38 PM on 16 February 2010
        Did Phil Jones really say global warming ended in 1995?
        There is much to do in the comments here about statistical significance. The post and some commenters have rightly pointed out that it is harder to reject the null hypothesis when sample sizes are small, particularly if the effect (in this case the trend in temperatures) is small. Two other points worth mentioning: 1. the significance level chosen for rejecting the null hypothesis is somewhat arbitrary; 2) choosing a particular null hypothesis entails making assumptions. Regarding the first point, Dr. Jones used the conventional 95 % threshold. What if he had selected 90 %? The trend might well be significant at that level. One the second point, choosing to test for whether the climate has warmed over the past 15 years (null hypothesis: there has been no change in global temperatures over the past 15 years) does not seem like a particularly useful test, given that climate is typically defined as the average conditions over 30 years. Finally, many branches of science (e.g. applied ecology) are moving away from hypothesis testing, in large part because of the aforementioned arbitrariness, and increasingly relying on Information theory, predictive ability, and related approaches.
124181. Marcus at 15:28 PM on 16 February 2010
        The Dunning-Kruger effect and the climate debate
        Jon, you are so seriously *off whack* that its barely worth responding, but I will anyway, so lets start with this: If what you were saying were true, that CO2 was simply transporting heat out into space, then why are we seeing a warming trend over the last 60 years (a time of declining solar irradiance)? Why are satellites showing a reduction in the emissions of IR radiation-in the wavelength which we *know* CO2 absorbs-into space over the last 30 years? Why has the stratosphere been *cooling* for the last 30 years (it would warm if CO2 were transporting heat into the upper atmosphere)? Why was the planet so much warmer during the pre-Quaternary Era, when the sun was significantly cooler? If this additional CO2 is so good for plant life, then why are we not seeing a significant rise in plant biomass? In fact, like any trace element, CO2 can become *harmful* for certain types of plants above a certain concentration-& there is a threshold above which additional CO2 has negligible impact on plant growth. Indeed, the warming for which CO2 is believed to be responsible can hasten senescence, which will result in a *reduction* in total biomass, & rising CO2 levels has been found to make certain crops less nutritious &-in some cases-even downright toxic. Yes plant biomass adapted to much higher levels of CO2 in the past, but they had *millions* of years to adapt, compared to mere decades. Also, its highly unlikely we're ever going to see the vast primeval forests of the Carboniferous Era-with their enormous trees-any time in the near future, so it is people like *YOU* are being reckless in assuming that we can just "reset" our atmosphere to Carboniferous Era levels without it having a detrimental impact on Quaternary Era life. However, the fact that you reject the science put forward by 70rn, but embrace the melodramatic rantings of rmbraun123 prove to me that you're not interested in *facts*, just your own sense of self-importance, which makes you a classic sufferer of the D-K effect!
124182. JonMoseley at 15:18 PM on 16 February 2010
        Is CO2 a pollutant?
        This entire discussion is flawed by the lack of a standard against which to measure what is "too much" or "enough" or "too little to be a problem." There is of course no science whatsoever - none, nada, no how -- to establish that OUTSIDE THE LABORATORY CO2 causes the Earth to warm. As I note elsewhere, CONVECTION is a dominant mechanism in the atmosphere that MOVES heat from the Earth's surface up to near space, where the heat is radiated to outer space. CO2 in the atmosphere MOVES. It is not anchored in place. So if CO2 absorbs heat, AND THEN MOVES by convection (as it must), this may simply increase the efficiency of the cooling mechanism of convection. Heat trapped near the Earth's surface is transported more efficiently to the upper atmosphere, and radiated into outer space. The point being that what we observe in the laboratory where a sample of gas is TRAPPED and unable to move is not meaningful for predicting how CO2 behaves int he open atmosphere. However, the question of what is the "RIGHT" amount is not science. It is simply an ego-centric and subjective belief.
124183. JonMoseley at 15:10 PM on 16 February 2010
        Working out future sea level rise from the past
        As for the orbital variations, you are all missing the boat quite dramatically. Review the analysis of "THE SWINGING SUN" by Dr. Landscheidt. The planets DO NOT technically revolve around the sun. ALL the bodies in the solar system revolve around the CENTER OF MASS of the solar system. This cuases the sun to "orbit" around a point which is NOT the physical center of the sun, but is the center of mass. The Jovian planets cause the sun to swing around a point in between the sun and the Jovian planets (though extremely close to the sun if not within it). This motion causes the sun -- a mass of plasma -- to slosh around the center of mass in a complex series of cycles ranging from the 11 year sunspot cycle (really 22 years) to 78 years, 170 years, hundreds of years ,and thousands of years. Take a large bowl of water and spin around. Watch the water. The sun's motion around the center of mass of the solar system creates pressure waves and variations in the sun.
124184. Tom Dayton at 15:06 PM on 16 February 2010
        Did Phil Jones really say global warming ended in 1995?
        hallewis, the consideration of the length of sample needed to detect a signal against the noise is an example of statistical power. It is a completely legitimate and important topic in statistics, but one that typically is not covered adequately, if at all, in high school and even college statistics and science classes. Here is just one of many introductions to statistical power. Phil Jones does not have a "limited knowledge of statistics." His comments were completely appropriate.
124185. JonMoseley at 15:05 PM on 16 February 2010
        Working out future sea level rise from the past
        First, the greatest factor in sea levels is the shape of the ocean floor determined by plate tectonics. The effect of plate tectonics creating massive chasms and mountains reshapes the "basin" in which the world's ocean water sits, affecting sea levels far more than any other factor. Second, if there were global warming, it would INCREASE the amount of snow, sleet, and rain on the polar regions. The polar ice caps would be GROWING if there were global warming, not shrinking. Sea levels would FALL, not rise. Evaporation from the ocean's surface (even below the boiling point temperature) accelerates when the water is warmer. An increase in the temperature of the ocean's surface would cause an increase in the humidity of the atmosphere, which -- EVENTUALLY (complex to be sure) -- would increase the humidity world wide. More water vapor in the atmosphere would precipitate when coming into contact with the colder air at the poles. Yes, the vast majority of the evaporation would precipitate at warmer climes, but there would still be a net INCREASE in the precipitation in the Arctic and Antarctic regions. Third, the temperature at the polar regions remains below the freezing point of water year-round. The temperature at Antarctica's coastline in Summer was -15 degrees C. An increase from -15 to -13.4 degrees C leaves the temperature still below freezing. How does ice melt below the freezing point of water?
124186. ejo60 at 14:56 PM on 16 February 2010
        Did Phil Jones really say global warming ended in 1995?
        I have lost my confidence in some media because they are making too many errors in reporting climate science. Also, I refuse to believe their errors are bad luck, it seems more like harassment by an overactive anti IPCC lobby group. In the Netherlands it is the Telegraaf and Elsevier that show this behavior. My policy is to avoid those media, moreover if you need to say something then insist that they start with a written press release and that you get to see their text prior to publication.
124187. David Horton at 14:43 PM on 16 February 2010
        Did Phil Jones really say global warming ended in 1995?
        It is as if he is having a polite chat in a seminar with colleagues who understand the subtleties of statistics and regression lines and variability and natural variation masking trends. He must surely have known that saying this on tv in the way he did would feed the deniaworld crazies?
124188. hallewis at 14:41 PM on 16 February 2010
        Did Phil Jones really say global warming ended in 1995?
        This is statistical garbage, and I find it hard to believe that he doesn't know it. To say that something isn't statistically significant at the 95% confidence level, but would be if you look a longer sample is to predict that you know what the longer sample will be, which in turn means that you take the lower significance as significant. He seems (as quoted. and I grant that he may have been misquoted) to have a limited knowledge of statistics.
124189. JonMoseley at 14:41 PM on 16 February 2010
        The Dunning-Kruger effect and the climate debate
        In post 64 70rn retreats into the known, to hide what is not known, arguing: "That co2 has absorption/emission towards the peak output of surface radiation is is well quantified ( I can give specifics if you like), the effect isn't an arcane knowledge, its ability to provide energy to the atmosphere has been known since the late 19th century by various disparate observers." This however, is irrelevant. The question is not what CO2 does in the laboratory but what it does in the extremely complex global eco-system and atmosphere. 70m repeats the fundamental fallacy of the global warming proponents. What is true in an overly-simplistic case is not necessarily true in a complex, multi-variable mega-system. First, as noted, CO2 is life-giving nourishment (of a fashion) to plant life. CO2 is not a pollutant, but the very building block of all life on Earth. Animal life requires plant life, which requires CO2. Just as increasing sugar as food to a culture will stimulate growth, it is reckless to ignore the effect of the Earth's plant life reacting dynamically to an increased presence of CO2. Life is extremely dynamic and adaptive, and to simply ignore its role is reckless. Is the Earth's plant life capable of absorbing more CO2 than it currently does? Has the Earth's plant life reached a maximum cap, beyond which it cannot absorb any more CO2? Well, we know that at times in Earth's history, the amount of plant life on Earth was vastly greater than today. So we know that we are not at the Earth's maximum capacity for plant growth. Secondly, how do we know how CO2 behaves in terms of heat in the open atmosphere? Answer: WE DON'T KNOW. We have absolutely no idea. The proposition is that CO2 abosrbs and traps heat. HMMMMMMM..... What happens to warm air in the open atmosphere? Hot air rises. The error is in assuming that CO2 at surface level will -- after absorbing heat -- WILL STAY at surface level. Is that assumption warranted? Can any theory be based on the assumption that CO2 - after being WARMED by capturing radiant heat -- will REMAIN at surface level? And if CO2 RISES by virtue of becoming warmer, then isn't it simply transporting heat from the surface up into the upper atmosphere, where it is radiated into outer space? Since CO2 is not anchored in place, but MOBILE, CO2's ability to absorb heat -- AND THEN RISE when heated -- may simply increase the efficiency of the TRANSPORT MECHANISM OF CONVECTION. The ability of the Earth to cool itself through CONVECTION of air from the surface to the upper atmosphere may be ENHANCED by CO2's properties of absorbing heat.
124190. JonMoseley at 14:26 PM on 16 February 2010
        The Dunning-Kruger effect and the climate debate
        Bern makes the same classic slip in post 59. Bern attempts to distinguish between biologic activity creating and consuming CO2, from what is wrongly portrayed as some kind of different or unnatural CO2. Of course, in reality, it is ALL nature. Nature put the fossil fuels in the Earth. Man did not. The fossil fuels are every bit as much part of Nature as a snail darter or warm, fuzzy puppy. The fossil fuels that Nature created have as much claim to be "NATURAL" as Bambi or Thumper. MAN DID NOT CREATE THE FOSSIL FUELS. Thus, in looking for a balance between CO2 creation and usage (consumption), Bern (like others) seeks to artificially distinguish between CO2 breathed out by lviing beings and CO2 released from 100% NATURAL fossil fuels, created by Nature, which Nature created, and Man had absolutely NOTHING to do with creating. Where do we imagine this CO2 came from? BUT, you say, CO2 has been stored -- by Nature -- and releasing it is "excessive." "Excessive" by whose standards? Since we know that at times the Earth has supported far more massive amounts of plant growth than exists today, we cannot merely assume that releasing stored CO2 won't result in compensating expansion of plant life. The error is in looking at only a subset of the total system, rather than the entire system as a whole.
124191. Marcus at 14:20 PM on 16 February 2010
        The Dunning-Kruger effect and the climate debate
        Yes John Moseley, the CO2 in fossil fuels was once present in our atmosphere. It took several hundred *million years* for atmospheric concentrations of CO2 to reach more than 3,000ppm-& a further several hundred million years for trees to sequester that CO2 from the atmosphere before being buried under many layers of sediment. Humans are now releasing these millions of years of CO2 in the space of just a few centuries-yet people like yourself would have us believe that this couldn't *possibly* have an impact on our atmosphere or climate. How about if I told you that the planet was an average of 6 degrees *warmer* when this CO2 was present in the atmosphere? Does that give you any sense of the danger we could be putting ourselves in?
124192. Doug Bostrom at 14:18 PM on 16 February 2010
        The Dunning-Kruger effect and the climate debate
        JonMoseley at 14:13 PM on 16 February, 2010 Jon, you should pause for a while and read this: Dr. Spencer Weart's Discovery of Global Warming
124193. Marcus at 14:16 PM on 16 February 2010
        The Dunning-Kruger effect and the climate debate
        Jon Moseley, would it be too much to ask that you learn to *read* before you go off on a multi-post tirade? It has already been pointed out that there are about a *DOZEN* sites, across the globe, that measure CO2 levels in the atmosphere at regions far from urban areas & at altitudes above the inversion layer. All of them are showing *THE SAME THING*-that CO2 levels in the atmosphere is rising at around 1ppm-2ppm per year, which is in direct accordance with the data from Ice Cores. It's just that Mauna Loa was the very first observation post to be built which monitored the atmosphere on a continuous basis. That you fail to comprehend this simple fact is *YOUR FAULT*-not the fault of previous posters. It is clearly a sign that you're a victim of the dreaded D-K effect! The best examples of egotism I've seen is from lay-people who believe they know more than scientists who've been studying in the field for over a decade-sound familiar?
124194. 70rn at 14:16 PM on 16 February 2010
        The Dunning-Kruger effect and the climate debate
        I would say that Jon Mosley's primary scientific method appears to be heavy handed use of the caps lock button, repeatedly, at multiple locations through out the post in varying conditions. That co2 has absorption/emission towards the peak output of surface radiation is is well quantified ( I can give specifics if you like), the effect isn't an arcane knowledge, its ability to provide energy to the atmosphere has been known since the late 19th century by various disparate observers. Similarly is absorption and emission is not just noted via the proxy of the atmosphere, but is observed by spectral analysis with in laboratory conditions. Again this not a myth, merely a property of it's molecular structure, which is known by a wide variety of practitioners in disparate fields, and can easily be verified by readily available equipment. Co2 is measured a numerous location other than Mauna Loa, and the consistency with which they align makes it's measurements suitable for use. This is also supported by measures from aerial observation devices. There isn't an elite inner circle, this science is the culmination of chemical, physical, geomorphology and climatological understanding involving countless thousands of individuals . Comparing current scientific process to a single classical philosopher isn't even vaguely relevant. @41 - I believe this to be applicable to your interests.
124195. Doug Bostrom at 14:14 PM on 16 February 2010
        It's the sun
        Dan, I take it then that you are the author?
124196. JonMoseley at 14:13 PM on 16 February 2010
        The Dunning-Kruger effect and the climate debate
        rmbraun123 gives a very thoughtful analysis of many points in post #41, yet worries that it is obvious that human use of fossil fuels is generating carbon dioxide. (Never mind the fact that humans did not create the fossil fuels, they have been on and in the Earth for millions of years before humans, and fires existed long before humans existed.) But this is not the question. The question is what happens in a massively complex global weather system. Plants thrive on carbon dioxide. CO2 is nourishment for plants, including algae. What is the NET effect of a source of carbon dioxide? After the stimulating effect to plant life and the gigantic quantities of algae in the oceans, what is the NET effect? It is not enough to say that Activity A produces CO2, without considering Activities B through ZZZ in the Earth's complex global systems. Because carbon dioxide is a life-giving, natural, healthy nourishment for plants -- a source of life -- it is quite a leap to assume that the ecosystem does not respond to the amount of CO2 in the atmosphere, by expanding plant life, and converting CO2 into Oxygen. A PROBLEM for the global warming proponents: Where did the fossil fuels come from????? The CO2 released by CO2 does not magically appear out of nowhere. CO2 from the Earth went IN to the fossil fuels, in order for it to come OUT again when burned.
124197. stevecarsonr at 14:08 PM on 16 February 2010
        Did Phil Jones really say global warming ended in 1995?
        The ocean heat content graphic is nice. The whole idea of measuring the "temperature" of the earth by averaging (area weighted) air temperatures 6ft off the ground (a proxy for surface temperature) with (area weighted) sea surface temperatures is just such a crazy idea. I realize the OHC has been hard to come by and even now deep ocean heat is a problem.. but still. The heat capacity of the atmosphere is 1/1000th of the heat capacity of the ocean.
124198. Marcus at 14:06 PM on 16 February 2010
        Did Phil Jones really say global warming ended in 1995?
        jasonk, I just went & did a quick calculation using data from GISS, & what I show for 1995-2009 is a warming event of +0.015 degrees per year, with an R-squared value of 0.41 (just below the 0.5 needed to be statistically significant). If I look at 2002-2009, I get a cooling event of only -0.003 degrees per year, with an R-squared value of only 0.02. If I look at 1995-2002 I see a warming event of +0.02 degrees per year, with an R-squared value of 0.22. So we have 2 relatively significant warming trends (1995-2009 & 1995-2002) vs a relatively *insignificant* cooling trend (2002-2009). So I'm curious as to what your point is? Well, aside from the dangers of cherry picking extremely short time frames! I'm much more interested in the trend for 1979-2009 (+0.016 degrees per year, R^2=0.709) & for 1959-2009 (+0.013 degrees per year, R^2=0.762).
124199. JonMoseley at 13:59 PM on 16 February 2010
        The Dunning-Kruger effect and the climate debate
        David Horton gets a failing grade in post 15, where he says: "Moseley and Westwell above have seen something, somewhere, perhaps on the WUWT site or similar deniablog, to the effect that CO2 concentrations in the air are variable." Wrong, totally wrong. One a proposition is advanced, it must be proven to be science. Horton wants to put an argument in my mouth, when it is the proponent of the original proposition who is responsible for establishing his proposition. The proposition was: "The reason why it's acceptable to use Mauna Loa as a proxy for global CO2 levels is because CO2 mixes well throughout the atmosphere." This is circular reasoning. This is stating the desired conclusion in support of coming to that conclusion. COULD IT BE THAT "CO2 mixes well throughout the atmosphere." ? Quite possibly, even probably. But do we KNOW this (recognizing that the global atmosphere is staggeringly complex in relation to a tank in a laboratory)? No. If you have the measurements necessary to establish that to a scientific certainty, then WHY DON'T YOU SIMPLY USE THOSE MEASUREMENTS around the globe, instead of relying on only one location? If you have the data world-wide, use it. If you don't have the data from around the globe, then you cannot really conclude that CO2 is evenly diffused throughout the world's atmosphere. The reason you are using a single measuring station, is that you DON'T have the necessary data world-wide to measure CO2 levels around the globe. PROXY SCIENCE IS A HOUSE OF CARDS, with one guess stacked upon another guess, stacked upon another guess, with errors, assumptions, misinterpretations, and biases multiplied many times over.
124200. JonMoseley at 13:48 PM on 16 February 2010
        The Dunning-Kruger effect and the climate debate
        Timothy Chase at post 11 comes dangerously close to returning to true science. Jargon aside, let us confront the fundamental divide between genuine science and malarkey. Aristotle was one of the wisest men who ever lived. For that reason, no one dared to question Aristotle's conclusions that a large body and a small body dropped from a tower would fall at different rates. Gallileo was more courageous than smart, though smart he was. Yet not as smart as Aristotle. But setting aside hero worship, Gallileo put it to the test by dropping 2 differently-sized cannonballs off the Leaning Tower of Pisa. One of the smartest men to ever live: WRONG A less-smart, relatively untrained Gallileo: RIGHT The egotism and belief that one is part of an elite inner circle CONTRIBUTES TO ERROR. It is a passionate commitment to the realization that one could be wrong which is the greatest safeguard against error. It is not the belief in one's own superiority that makes science, but the humility of believing in one's own fallibility that creates genuine science.

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