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Comments 67051 to 67100:

67051. Tom Curtis at 08:53 AM on 5 January 2012
       Myth of the Mini Ice Age
       boba 10960 @10, the Ridgwell 2003 addresses the rapid rise in CO2 levels from 17 thousand to 11 thousand years before the present, and hence is not germane to the rise in CO2 levels during the Holocene. Broecker and Stocker 2006 is interesting. It is noteworthy, however, that CO2 levels rose significantly faster in the Holocene than in their chosen comparison of period of the Milankovitch stage 11 (approx 410,000 years ago). What is more, the Holocene increase in CO2 levels is set against a backdrop of cooling global temperatures, while the equivalent period in the comparison with stage eleven is for warming global temperatures. Bill Ruddiman points out an even greater disanalogy. Whereas in the Holocene northern insolation peaked 11 thousand years ago, and have been declining since, in stage 11 they continued to rise strongly until the equivalent of 2,000 years ago (in the comparison) so that the standard comparison compares a NH peak in insolation to the current trough in order to prove that an Ice Age could not have commenced recently without the influence of humans. Given the very large known deforestation by humans in the pre-industrial era, not the mention the artificial expansion of swamp lands in Asia due to rice cultivation, it is certain that pre-industrial humans had some effect on CO2 levels, and likely that they contributed at least half of the rise in CO2 over the last 7,000 years. I will certainly concede that it is controversial whether they contributed more than that. However, that they contributed enough to prevent the onset of a new ice age remains possible on available evidence (SFAIK). Hence it is not a "myth" as claimed by skept.fr @6. Nor of course, is it certain, but I have never claimed otherwise.
67052. mace at 08:09 AM on 5 January 2012
       Models are unreliable
       Any ideas where the satellite data shown in the main picture comes from? It doesn't seem to match any data that I'm aware of.
       Response:

       [DB] "Any ideas where the satellite data shown in the main picture comes from?"

       Did you read the linked source?

67053. boba10960 at 08:05 AM on 5 January 2012
       Myth of the Mini Ice Age
       Excellent video! A short comment for Tom Curtis @8: Note that the hypothesis that human activities influenced the rise of atmospheric CO2 after 7500 BP is highly controversial. For a rebuttal see Broecker and Stocker 2006 An alternative hypothesis for the rise in CO2 after 7500 BP is the regrowth of coral reefs following the end of the last ice age Ridgwell et al., 2003. Growth of corals and other organisms that generate calcium carbonate shifts the acid-base balance of seawater which, in turn, releases CO2 from dissolved inorganic carbon.
67054. Chris G at 07:08 AM on 5 January 2012
       A Big Picture Look at Global Warming
       CW, For your IPCC references, could you tell use what the context is for 'high' and 'low'? I'm thinking there are scenarios for high and low emissions paths, and maybe high and low climate sensitivities, but I'm not sure I've heard of any 'rapid' versus 'slow' warming scenarios, strictly speaking. What I'm saying is that you are comparing apples and oranges. If you examine the all the rates of change over the earth's history, would the rate of change since the industrial revolution began fall near the upper end of that range, or the lower? Aside from some other candidates like major impact events or super-volcano eruptions, I'm pretty sure the current rate is very near the upper limit of the range. Any reason you choose CRU rather than GIS or BEST? I was kind of under the impression skeptics did not trust the results from that unit, given the controversy surrounding Dr. Jones and all. Dana, Thanks! I had a thought though that what really matters is ice mass or ice volume. So, rather than say southern sea ice extent growth is more than eclipsed by northern ice extent loss, you could say that both are loosing mass at an accelerating rate. I understand that isn't a simple comparison though because mass loss for Antarctica and Greenland is measured with gravity satellites (GRACE) and it is harder to measure Arctic sea ice volume than it is extent. However, losses in both hemispheres is a simpler message.
       Response:

       [dana1981] Good point - text revised to reference Arctic sea ice volume and Antarctic ice mass declines.

       As I noted in response to CW's comment, he is comparing future projected temperature changes to past/current temperature changes.  As you note, it's an apples to oranges comparison.  Showing that the planet isn't yet warming as fast as we expect it to in the future most certainly doesn't demonstrate that the warming thus far isn't rapid.  It's just expected to become more rapid in the forthcoming decades.

67055. ClimateWatcher at 06:34 AM on 5 January 2012
       A Big Picture Look at Global Warming
       ...the planet is not "rapidly warming," although "rapid" is a highly subjective term, which they have failed to define. Per IPCC: Best estimate for a 'high scenario' is 4.0 °C per century Best estimate for a 'low scenario' is 1.8 °C per century Actual trend for CRU since Jan 1979 is 1.5 °C per century. Per IPCC: A temperature rise of about 0.2 °C per decade is projected for the next two decades for all SRES scenarios. Actual trend for CRU since Jan 2001 is -0.05 °C per decade (cooling). By the objective measure of the longer term trend, the planet is not "rapidly warming" but is "slowly warming".
       Moderator Response: [Rob P] You seem to not understand the 'big picture.' Note figure 1 - labeled - Change in Earth's total heat content. Since 2001 that has increased substantially - as we would expect given our understanding of physics. See also:

       

       There has been a massive increase in ocean heat content since 2001. The ocean heat content will likely decline temporarily if we have another large El Nino or sequence of El Nino. La Nina is when the ocean actually gains heat, and since we have been in a largely La Nina dominated period since 2005-2006, it's little wonder global surface temperatures have not changed much. If we see a change to an El Nino-dominant period, we're going to get warming of global surface temperatures quick smart.

       [dana1981] You have committed two errors in this comment, (1) cherrypicking (both the data set and the timeframe - see Figure 2 above regarding the latter), and (2) comparing current warming rates to future projected warming rates.  Thus you have not justified your (incorrect) conclusion.  At best your argument is that the planet is warming more slowly than expected (although even that point is incorrect), but this would not prove that the planet is not warming rapidly.

67056. John Russell at 06:14 AM on 5 January 2012
       Science and Distortion - Stephen Schneider
       @Tom #40 You're quite right with everything you said after "What should be recognized...". You know it; I know it; and so will everyone who arrives at this point in this website. However... The point that climatehawk1 was making -- and he's dead right -- is that a large majority of the population (I'm guessing over 70%) will not understand a word of what you said in the remainder of your comment. All they hear is '4 watts' and think 'that's not much'. And these are the people we need to get to. The denial community is way ahead of us when it comes to influencing 'the man in the street'.
67057. Rob Honeycutt at 04:03 AM on 5 January 2012
       Science and Distortion - Stephen Schneider
       Well, put Tom (@41). The point that needs to be made, and I think rarely does (and what I love about what Schneider is saying), is that the act of giving equal time to two sides of the debate distorts the perception of the reality of climate science. In fact, it's worse than that. You rarely ever see the "screaming hairy conniption fit" (Richard Alley's term) AGW side of the story, whereas you DO almost constantly get the "screaming hairy conniption fit" on the denier side. Even from main stream "skeptics" you get this. Never mind folks like Monckton, just reading Richard Lindzen's NYT OpEd this past year the term that pops into your head is "wow, what a screaming hairy conniption fit he's on!" What you get from the actual climate science community is generally very careful nuanced responses that do little to counteract the conniptions on the other side. The actual debate in climate science takes place within a fairly narrow range of potential forcing responses. But it sure is hard to sell main stream news on that kind of story.
67058. Philippe Chantreau at 03:18 AM on 5 January 2012
       Models are unreliable
       If I were James Wilson, I would rant on about this paper being a religious paper and the authors not being able to refrain from political argument. I would then say how it got published because of a sympathetic reviewer and that it will certainly be torn apart in subsequent analyses etc etc... Yet I'm sure that, somehow, it will make Poptech's list. Isn't it nice to have flexible standards?
67059. KR at 03:06 AM on 5 January 2012
       Models are unreliable
       Curiously, the publisher of the Kramm and Delugi article, Scientific Research Publishing, is an open access (translation, pay to be published) set of journals with a curious reputation for (re)publishing old articles, listing academics on the editorial boards much to the surprise of said academics, who in some cases had agreed to be associated with different journals, and in others had not agreed to any relationship. The publisher appears to be based in China, but details of the publisher, staff, etc., are very hard to come by. While not E&E (with an editorial policy of posting papers just because they disagree with the consensus), I would consider SRP a not terribly reliable source...
67060. Cornelius Breadbasket at 02:44 AM on 5 January 2012
       Models are unreliable
       Tom @ 445 Thank you. Beautifully clear. I was quite disturbed by the use of language in the abstract - it was not particularly objective and used emotive terms. Please do expand this to a full blog post.
67061. Tom Curtis at 02:32 AM on 5 January 2012
       Models are unreliable
       John Hartz, no I haven't. I have discussed in slight detail two arguments out of many in a large, and confused paper. I may consider a blog post on the issue after following through SoD's series.
67062. John Hartz at 02:09 AM on 5 January 2012
       Models are unreliable
       @Tom Curtis #446: You have just written a blog post. Go for it!
67063. Tom Curtis at 01:04 AM on 5 January 2012
       Myth of the Mini Ice Age
       Cornelius Breakbasket @7, I have read a bit of their paper, and commented in more appropriate thread. Short answer is that the paper as a whole is pseudo-scientific nonsense.
67064. Tom Curtis at 01:01 AM on 5 January 2012
       Models are unreliable
       I have now looked briefly at Kramm and Delugi. One thing I noted is that large sections of the introductory material is more diatribe than discussion. More troubling to me, however, where sections like the following:

       "The notion “global climate”, however, is a contradiction in terms. According to Monin and Shishkov, Schönwiese and Gerlich, the term “climate” is based on the Greek word “klima” which means inclination. It was coined by the Greek astronomer Hipparchus of Nicaea (190-120 BC) who divided the then known inhabited world into five latitudinal zones—two polar, two temperate and one tropical—according to the inclination of the incident sunbeams, in other words, the Sun’s elevation above the horizon. Alexander von Humboldt in his five-volume “Kosmos” (1845-1862) added to this “inclination” the effects of the underlying surface of ocean and land on the atmosphere."

       Of course, it is obvious that in modern usage that climate does not mean "inclination" as in the angle of the sun. In fact, it currently means, as defined by the IPCC and WMO:

       "Climate Climate in a narrow sense is usually defined as the average weather, or more rigorously, as the statistical description in terms of the mean and variability of relevant quantities over a period of time ranging from months to thousands or millions of years. The classical period for averaging these variables is 30 years, as defined by the World Meteorological Organization. The relevant quantities are most often surface variables such as temperature, precipitation and wind. Climate in a wider sense is the state, including a statistical description, of the climate system. In various chapters in this report different averaging periods, such as a period of 20 years, are also used."

       Now, patently it is possible to determine the mean and variability of temperature, precipitation, wind speed, frequency and types of extreme events for the Earth's surface just as it is possible to do so for some subpart of the Earth's surface, say Texas. It follows that the only way “global climate” can be "a contradiction in terms" is if, for example, the "the climate of Texas" is a contradiction in terms, or indeed, if "the climate of Houston" is a contradiction in terms. As it happens, the Ancient Greek word "οἰκονομία" from which we derive the term "economics" means "household management". Kramm and Dlugi's argument that global climate is a contradiction in terms is as coherent as an argument that there is no such thing as the world economy because the world is not a household, and economics means household management. Such nonsense verbal arguments are a clear sign of pseudoscience, and their prominent presence and Kramm and Delugi shows that it is ideology, not science that drives their work. However, that is not the reason I am discussing their work on this thread (which would be off topic). Rather it is because of their critique of the WMO definition of the greenhouse effect. In that critique they correctly develop a zero dimensional model of the global energy balance. They then proceed to criticize it because: 1) Surface storage of energy is not considered in the zero dimensional model; 2) The zero dimensional model assumes the entire Earth's surface has the same temperature; 3) The albedo used in the equation includes contributions to the Earth's total albedo from the atmosphere, and not just those from the surface only (I kid you not); 4) Comparing T_e, the predicted temperature required to maintain equilibrium temperature with T_ns is inappropriate because T_e is the theoretically predicted temperature and T_ns is the actually observed temperature. (Again, I kid you not!) 5) The observed mean surface temperature of the Moon is 31 degrees Kelvin lower than that predicted for the moon using the Zero dimensional model. I note that all five objections are true. Some are bizarre stated as objections, or course. For instance, it is always true in any prediction that the prediction is not the measurement. To conclude from that, as Kramm and Dlugi do in their fourth objection is breath taking, to say the least. It shows a gall not found even in creationists. One objection, the fifth, does need a small comment. It is well known that surfaces with variable temperatures will radiate away more energy than similar surfaces with even temperatures given that they have the same mean temperature. This is so well known that planetary scientists never use the zero dimensional model used by Kramm and Dlugi for planetary bodies known to have very large heat differences at their surface (such as the moon). Further, because of this it is also known that the estimate of the greenhouse effect obtained by zero-dimensional models are an underestimate of the full strength of the greenhouse effect, although still a good first approximation. And that is the point, really. Zero dimensional models are only intended to provide a first approximation. They make counter factual but convenient assumptions for simplicity knowing that they are not determining the exact effect. In this regard they are like other physics models that ignore friction, or wind resistance, or (as famously done by Newton) the extended nature of planetary bodies. Of course, climate scientists do not rest on first approximations and zero dimensional models. Instead they develop more complex models which eliminate the simplifying assumptions used in zero dimensional models. Coupled Ocean-Atmosphere Global Circulation models (AOGCM) include, for example, (1) heat storage and transport by atmosphere and ocean; (2) variable surface temperatures; and (3)surface only albedo at the surface, with atmospheric contributions to albedo included in the modeled atmosphere. In other words, not one of Kramm and Dlugi's objections (that can be taken at all seriously) is an objection to AOGCMs. That being the case, Kramm and Delugi's argument logically devolves to this: The predictions of AOGCMs are necessarily wrong because zero dimensional models are only first approximations. Nothing more need be said to refute them, and having stated their argument, nothing could ever make me take them seriously again.
67065. John Russell at 00:34 AM on 5 January 2012
       Quantifying Extreme Heat Events
       I know it's a rather an indirect indication of heat build-up compared to the graphs in the article above, but to a layman like me this NOAA graph is much more compelling and -- if I was a US citizen living in the Southern States -- very frightening. [Note to moderator: please insert the graph if you think it's worth it.]
       Response:

       [DB] Graph inserted:

       

67066. Tom Curtis at 23:57 PM on 4 January 2012
       Myth of the Mini Ice Age
       skept.fr @6, around 7,500 years ago, atmospheric CO2 levels hit a low point for the period since the last major glaciation. By best estimates, CO2 levels have increased since then in large part due to human agricultural activities, particularly wet land farming (rice), herding (cattle) and general deforestation. The total addition of CO2 to the atmosphere by these means has amounted to about 200 Giga-tonnes of Carbon, or 734 billion tonnes of CO2. That represents an atmospheric concentration of CO2 of approx 94 ppmv. In other words, without human activity, there is a significant probability that in 1750 CO2 concentrations could have been as low as 190 ppmv. Of course, reduced atmospheric concentrations would have resulted in net out gassing rather than absorption of CO2 by the ocean, so the CO2 level absent a human presence in 1750 may have been as high as 230-40 ppmv. (Information derived from Indermühle et al 1999.) The crucial point here is that although Berger and Loutre 2002 found no example of a new glacial (ice age) under known orbital forcings with a CO2 concentration equal to preindustrial levels, with a CO2 concentration of 210 ppmv they found renewed glaciation. That is an intriguing number, for while CO2 levels may have stayed above that level in the absence of man, it is by no means certain that they would have. Indeed, given that CO2 levels would fall with falling sea surface temperatures, it is probably more likely than not that, absent the presence of man the Earth would now be entering its next glacial stage. It should be noted that Berger and Loutre did not set out to, and do not claim to refute this possibility. Rather, they set out to refute belief among some paleoclimatologists in 1972 that "a slide into the next glacial seemed imminent", ie, that given 1970's CO2 concentrations a new ice age was imminent but for industrial emissions.
67067. EOttawa at 23:52 PM on 4 January 2012
       Quantifying Extreme Heat Events
       @23 mreisner, a 2011 paper published in Nature looked at human influence on precipitation extremes in North America: Human contribution to more-intense precipitation extremes Seung-Ki Min, Xuebin Zhang, Francis W. Zwiers & Gabriele C. Hegerl
67068. Cornelius Breadbasket at 23:01 PM on 4 January 2012
       Myth of the Mini Ice Age
       Tom Curtis @5 Thank you.
67069. skept.fr at 22:49 PM on 4 January 2012
       Myth of the Mini Ice Age
       Nice video. There is sometimes a related "myth", that GHGs prevent us from entering to the next glacial period, that alternates (normally) with interglacial periods during the Quaternary, due to solar orbital forcing also called Milankovic cycles. But in fact, Berger et Loutre 2002 calculated that the present interglacial should last for 50.000 yrs, because of solar parameters. So, no need to worry an ice age if GHGs' emissions are cut (for a free paper of the same authors on the same theme, Loutre et Berger 2000)
67070. Tom Curtis at 22:39 PM on 4 January 2012
       Myth of the Mini Ice Age
       Cornelius Breadbasket @4, Science of Doom has posted the first part of a multi-part examination of Kramm and Dlugi 2011. I may comment later and in a more appropriate thread once I have read the paper.
67071. Cornelius Breadbasket at 22:30 PM on 4 January 2012
       Myth of the Mini Ice Age
       Thank you! Sinclair is excellent - as is his blog. I'm sorry if this is a little off-topic but I don't have any other way of communicating with Skeptical Science. I have been 'made aware' of this a paper which looks extremely suspicious to me and I wondered what your take on it is. Natural Science, Vol.3 No.12, December 2011 Scrutinizing the atmospheric greenhouse effect and its climatic impact by Gerhard Kramm, Ralph Dlugi It seems to conclude that "energy-flux budgets for the Earth-atmosphere system do not provide tangible evidence that the atmospheric greenhouse effect does exist" - which strikes me as nonsense. Any more enlightened opinions than my own would be very welcome.
67072. actually thoughtful at 16:58 PM on 4 January 2012
       Quantifying Extreme Heat Events
       A truly frightening perspective. If you wonder how the deniers will deny, it will look like this: "There isn't one shred of evidence that ties the increased heat to CO2 emissions. It is more likely ... (probably the Cosmic Ray thingy - that seems popular these days).
67073. John Brookes at 15:41 PM on 4 January 2012
       Myth of the Mini Ice Age
       Thanks! Excellent video.
67074. Tom Curtis at 14:36 PM on 4 January 2012
       Science and Distortion - Stephen Schneider
       barry @39, indeed, not ideologues at all. Our purpose is to enable people to access the evidence as determined by the consensus of climate scientists based on the overwhelming body of evidence, rather than the message from fossil fuel funded think tanks based on cherry picked data which gets 50% of the time in mainstream media, and 100% in Fox News. As Stephen Schneider indicates, when 97% of relevant scientists agree on something, and less than 1% of relevant scientists plus a few non-qualified people only in the debate for ideological reasons and accorded a position of expertise they demonstrably do not warrant get the same amount of the time on mainstream media to get their idea out as to the 97%, with no reporting of the relevant qualifications credibility of the two position, that "...is not balance, it is utter distortion!" (3:40 fwd). What we are trying to do here is to restore the balance by reporting the science.
67075. Tom Curtis at 14:22 PM on 4 January 2012
       Science and Distortion - Stephen Schneider
       climatehawk1 @38, you are quite right about some ordinary people and mention of 4 Watts. What should be recognized is that it is 4 Watts per square meter over the approximately 510 trillion square meters of the Earth's surface, or 2040 trillion Watts. That represents more than 150 times the total human primary production of energy in 2008 (EIA figures), including renewable energy. Primary production includes energy lost as waste heat as well as that actively used. That should place the ordinary persons 100 Watt bulb into perspective.
67076. barry1487 at 13:15 PM on 4 January 2012
       Science and Distortion - Stephen Schneider
       Interesting to be discussing climate change PR on a website nominally dedicated to an objective explanation of the science. It seems just a tad off-key - not that there should be a bar on such discussion, but a first time visitor reading this thread would likely get the impression that this is an advocacy site. Which it is, but almost always only by implication. The committed contrarian might read this thread as an unwitting expose on the motivations of the regulars, commenters and contributors alike. "See, they're ideologues" (Message for contrarians - they're not ideologues)
67077. climatehawk1 at 12:29 PM on 4 January 2012
       Science and Distortion - Stephen Schneider
       tmac57 - #35 - You're right, Climate Denial Crock does mention the myth, at least sometimes. An excellent example is the "Myth of the Mini Ice Age," just posted today. Compare it with the Schneider video, and the difference is quite striking--it mentions the myth once or twice, but it cuts off the non-scientist gentleman from the fossil-fuel-funded Competitive Enterprise Institute after a single sentence and then goes into straight debunking. The ratio of debunking to myth is far higher. Rob Honeycutt - #36 - You know, you should just show it to a couple of focus groups and see what they tell you. I think you will be amazed at how little average folks know and how easily they are confused. Only when the video gets about 2/3 of the way through and shows the cigarette spokesman (or reporter, whichever it was) does it really become clear what is being shown. EOttawa - #37 - I agree, excellent motivator for scientists who know the score. For ordinary people as an intro? Sorry, won't work. I can just see one saying, "What, 4 watts? That's tiny! I have a bunch of 100-watt light bulbs in my own house! ... " No disrespect to Dr. Schneider intended here--I agree he was a giant in the field. But setting that aside, this is simply not a suitable or effective tool for communicating climate science to a general audience.
67078. neilrieck at 10:43 AM on 4 January 2012
       CO2 is plant food
       "Inputs to Photosynthesis" The first stage involves the photolysis of water by sunlight (this is the only place where oxygen is released to the atmosphere). This diagram: http://www3.sympatico.ca/n.rieck/images/photosynthesis-chloroplast.jpg ...is proof that sunlight (input 1) and water (input 2) are more important than CO2 (input 3) but each ingredient is considered a limiting factor to maximum photosynthetic productivity. "Push vs Pull" Just as eating (push) a protein supplement will not make you muscular unless you exercise (pull) which creates a demand for protein. So simply adding more CO2 (push) will not make photosynthesis run at a higher rate, unless CO2 was the only limiting factor. On top of that, CO2 has risen 24% since I've been alive (395/315) so we should have seen an explosion of plant life as compensation for the additional CO2 but we have not. "Drop in Photosynthesis due to Temperature" There is considerable published evidence showing that C3 photosynthesis production drops by 10% for every "F" degree over 76. Why? The stoma on the underside of leaves is the place where "CO2 enters" and "H20 can escape". At 86F most C3 plants have closed their stomas 100% to stop water loss (but this also stops photosynthesis). C4 and CAM plants have adaptations to deal with higher temperatures but the adaptations come at a cost (some of the solar energy powers the additional molecular machinery). Pineapple is one example of a CAM plant (hint: CO2 is pulled in at night). BTW, 85% of all plants are C3
67079. skywatcher at 10:35 AM on 4 January 2012
       Quantifying Extreme Heat Events
       #29 Sphaerica. It should scare people, after all, this paper documents observations of increasing extremes, and is not a prediction of the future. Perhaps JamesWilson does not believe that the 2003 European heatwave happened, or the 2010 heatwave, or the 2011 southern US heatwave? After all, it's in a Hansen paper. It couldn't actually have happened, could it? #28: Jose_X - looks like you more-or-less answered your own question. If you want to analyse the variability within the two different datasets, then you'd use a baseline calculated from within those datasets, but that would tell you nothing of how the datasets' absolute values changed from one to another. For documenting how different one datset is from another, the Hansen approach is perfectly valid. We can see that 2010 and 2011 have a lot more warm extremes across the globe compared to individual years before 1980, and that this trend is increasing.
67080. Bob Lacatena at 10:21 AM on 4 January 2012
       Quantifying Extreme Heat Events
       25, JamesWilson, The majority of your comment is in clear violation of the comments policy, and should be deleted. That said... a) What paragraph are you talking about? I see nothing remotely like an attack. You quoted the word "opponents" but it does not occur in the paper. Please support or withdraw your assertion. b) "...there is no equations or real description of how to reproduce his numeric model." There rarely is. Anyone competent should do so on their own, not by replicating Hansen's methods exactly but by approaching the problem themselves. That's how science is normally done. Your complaint is invalid, and uneducated. The rest of your comment is a tiresome rant of its own, and a clear violation of the comments policy. It represents your personal opinion, and is at odds with the clear and inarguable data presented by the paper. Do you have anything to say about the content, rather than your perception and opinion of the way it is phrased, or an otherwise unsupported dismissal of the results? Doesn't it scare you just a little?
67081. Jose_X at 10:20 AM on 4 January 2012
       Quantifying Extreme Heat Events
       I am confused. If the sigmas are calculated based on one set of values (50-80) and then the temperatures go up on average (global warming). Then the 03-11 values are very likely to be skewed up and at a greater sigma value. The paper mentioned something about removing the linear trend in one scenario. Even with that removal, the values are a little more likely to be extreme. Now, perhaps the extremes have become worse, but why would you use the sigma of one set of points to judge a different set? I am not a statistician, but let me give an extreme example to show what I mean. If you calculate sigma off a set of values like 9, 11, 12, 13, 13, and 13, you get a small value near 1. If you then test that sigma on a new set of numbers, for example, a set that is proportionally equivalent to the first: 90, 110, 120, 130, 130, and 130, then every data point in this second set will generally be off by many of the sigmas calculated on the first set. .... On the other hand, if humans are adapted to a sigma of 1 and you jump to a sigma of 10, while the 10 might be absolutely sane and logical, the organisms that were adapted to sigma of 1 would likely be in trouble. .. OK, I am not so confused any longer. [Thankfully, these numbers I just used for the demonstration were much much more extreme than what we are experiencing in temp readings worldwide.]
67082. michael sweet at 10:13 AM on 4 January 2012
       Quantifying Extreme Heat Events
       James, The data for the analysis are freely available at GISS. I have described the analysis in sufficient detail to reproduce Hansen's data. Hansen gives more detail than I have included. If you do not understand how to calculate a standard deviation you should hold back on your comments, my students in High School are required to learn standard deviations. This paper has been on the web for two months. Can you point to a serious criticism of it?
67083. Philippe Chantreau at 10:11 AM on 4 January 2012
       Quantifying Extreme Heat Events
       What are you talking about James Wilson? The paper simply looks at temp anomalies. All the data are readily downloadable from GISTEMP. Get the data, calculate the averages, subtract the baseline averages from them and you get the anomalies. That's what the numerical model is. The time periods considered are clearly indicated in the paper. I expect the gridding is the usual GISTEMP 200 km boxes (is it 200? I forget). Not that a different gridding would make much difference anyway. For the next part, you need to know what standard deviation is and have some basic knowledge of stats. If you don't, acquire it before you try to reproduce the results, as you would have no business doing so without the knowledge base. Once you know how to do it, then you can calculate your own standard deviation, a much fruitful endeavior than reusing someone else's equations, which would not constitute reproduction of results and would not validate anything. All the following graphs are based on deviations as compared to the standard deviation. Once you have the necessary numbers, just plot them on a graph. All this can be done with the info that is in the paper and the GISTEMP data. Have at it. Furthermore, this paper is not yet formalized for publication, this caveat is clearly stated on top of the thread. Your insinuations that it will pass peer-review out of sympathy in its current form are unwarranted.
67084. JamesWilson at 09:23 AM on 4 January 2012
       Quantifying Extreme Heat Events
       This reads like a religious paper not a scientific paper. Let me explain: First of all there is no equations or real description of how to reproduce his numeric model. We are expected to have faith that his numeric methods are valid. Then half way through we get an attack on his "opponents". Forget what the attack is: What does this paragraph have to do with the Science discussed?!? The writer has such a political agenda he can't even get through a 4 page paper without a purely political criticism from someone completely unrelated to the subject at hand... I predict it will travel the path of most faith based documents. It will pass the peer review process by someone sympathetic. Be flogged at press releases and then be ripped apart within 18 months as what it is. Unscientific. It doesn't mean anything about Global Warming if this gets ripped apart. It should be labelled for what it is: Political commentary or Religion. Take your pick.
       Response:

       [DB]  Your comment contains several inflammatory bits of ideological rhetoric, as well as insinuations of academic fraud and/or dishonesty.  All of which are violations of the Comments Policy.  Please better conform to said policy, as future, similar, comments will be simply deleted.

67085. John Hartz at 07:37 AM on 4 January 2012
       Myth of the Mini Ice Age
       @Rob Honeycutt: Suggest that you embed a link to Sinclair's blog in the first sentence
       Response: [JC} Added, thanks for the suggestion.
67086. muoncounter at 07:29 AM on 4 January 2012
       It hasn't warmed since 1998
       mace#143: "why the global mean temperature increase appears to have stalled." It hasn't stalled. See the Foster and Rahmstorf thread. "The resultant adjusted data show clearly, both visually and when subjected to statistical analysis, that the rate of global warming due to other factors (most likely these are exclusively anthropogenic) has been remarkably steady during the 32 years from 1979 through 2010. There is no indication of any slowdown or acceleration of global warming, beyond the variability induced by these known natural factors." It would be helpful if, as scaddenp suggests, you provided the source of these assertions: '___ says temperature increase appears to have stalled.'
67087. John Hartz at 07:28 AM on 4 January 2012
       Temporarily Frozen Planet, Permanently Frozen Objectivity
       Attenborough hits back at claims made by former Chancellor Nigel Lawson that the BBC’s natural history series, Frozen Planet, lacked objectivity. Source: “David Attenborough: Frozen Planet was not alarmist about climate change”, The Guardian (UK), Jan 3, 2012 To access this informative article, click here.
67088. scaddenp at 07:22 AM on 4 January 2012
       It hasn't warmed since 1998
       In one breath, we have "why the global mean temperature increase appears to have stalled" - well Foster & Rahmstorf 2011 deal to that. Next breath we have a UK only data used to support the assertion? Classic cherry picking. This sounds like repeating a meme from a denialist site. Care to tell us which one?
67089. scaddenp at 07:16 AM on 4 January 2012
       Tree-rings diverge from temperature after 1960
       Also note that public science is interested in finding out what we don't already know. You can't get funding "to prove AGW" - you can only get funding to further understand the climate system. Science follows whereever the data leads you. Not so for "industry science". FF companies have the resources to run climate models (I work in the industry) but what would be the point? Disinformation is much cheaper. Do you think Fred Singer is going to publish data in support of AGW if that is where his "research" took him?
67090. Louise at 07:03 AM on 4 January 2012
       SkS Weekly Digest #31
       Time to nominate for the Bloggies 2012 http://2012.bloggi.es/
67091. DrTsk at 06:58 AM on 4 January 2012
       Myth of the Mini Ice Age
       Myths of Mini Age even if they persist for now, will completely disappear within a few years. So, report facts, ignore myths!! Thanks once again to Peter.
67092. scaddenp at 06:36 AM on 4 January 2012
       Tree-rings diverge from temperature after 1960
       The "billions" almost all go into satellites. Climate science remuneration (or for that matter any public funded scientist) is not closely tied to their level of funding. You can't spend research funds on fancy living. Not so with misinformation money.
67093. Philippe Chantreau at 06:20 AM on 4 January 2012
       Tree-rings diverge from temperature after 1960
       DSL, No doubt he woud make a great modern Tartuffe...
67094. Hyperactive Hydrologist at 06:04 AM on 4 January 2012
       Quantifying Extreme Heat Events
       mreisner, That is significantly more difficult to do due to the complex nature of rainfall and the sparse data coverage of much of the globe. Current statistical technique for analysing trends or change points in the data are, to put it mildly, not very good.
67095. John Hartz at 05:38 AM on 4 January 2012
       SkS Weekly Digest #31
       Attenborough hits back at claims made by former Chancellor Nigel Lawson that the BBC’s natural history series, Frozen Planet, lacked objectivity. Source: “David Attenborough: Frozen Planet was not alarmist about climate change”, The Guardian (UK), Jan 3, 2012 To access this informative article, click here.
67096. les at 03:32 AM on 4 January 2012
       Tree-rings diverge from temperature after 1960
       I kind of had this discussion with a someone on FB just after climetEmailTheft1.0 regarding grants at CRU... I looked at some leaked spreadsheet and was astonished at the low level of funding people where counting as "grand larceny"... especially when you consider that in the UK Universities charge grants <40% overheads, stipends include tax, NI, pensions etc. I've seen better grant capture in many other disciplines - with nothing going into the pockets of academics. Running a unit in a university is both extremely expensive (compared to grant levels available) and highly audited. The only way an academic can end up with some cash is through consultancy (you could easily pay 80% or 100% overheads on that also, before income tax).
67097. mreisner at 03:30 AM on 4 January 2012
       Quantifying Extreme Heat Events
       Anyone aware of a similar global analysis of "extreme precipitation events?"
67098. Bob Lacatena at 03:15 AM on 4 January 2012
       A thoughtful conservative perspective on climate
       67, Eric, Agreed. I am disappointed with how quiet and complacent the Democrats have been on climate change, although the current economic fears, exacerbated by the way the Republicans trumpet and prey on those fears, are a big reason. I'm not sure the Dems wouldn't have done more if they had more wiggle room, or that they won't do more during the next administration, when (a) climate change is more obvious and (b) either Obama is in office but no longer facing re-election, or a Republican is in office and the Dems can at least make it into an important issue and force a Republican president or House (or Senate?) to actively and publicly halt legislation. But the fact is that the only way this will really get done is if both parties cooperate. Unfortunately, the current Republican congressmen and women appear to be beholden to business and fossil fuel interests, so it will take something of a cosmic earthquake to shake them into taking the issue seriously.
67099. DSL at 02:25 AM on 4 January 2012
       Tree-rings diverge from temperature after 1960
       Dawson, you're also ignoring how the money is used. Scientists use money to do science. Organizations such as The Heartland Institute use money to change public opinion and to do so without supporting evidence. That's all they do. Any science these organizations support directly (through funding or publication opportunities) is not meat-(or tofu)-and-potatoes, everyday science; it is scientific or, rather, statistical work attempting to find a rhetorically exploitable weakness in the prevailing theory. If the opposition to the theory of AGW provided an alternative theory that covers the evidence and physics even half as well as AGW, this would be an interesting conversation. There is no such alternative theory, yet some people continue to insist there must be--there must be. What do you call people who believe in a "how things work" that relies on an absent physical mechanism(s) and ignores a range of evidence? Phillipe: Molière would salivate over the deeply hypocritical figure of Wegman and his ripe-for-satire situation.
67100. John Russell at 02:17 AM on 4 January 2012
       North American mammal evolution tracks with climate change
       @James Wilson #4 Funny, isn't it? Impact by asteroid could be considered by some to be 'alarmist' talk propagated by 'chicken littles'. Yet no one denies their existence or decries the amount that NASA spends every year to track them. Indeed if NASA ever announced the necessity to spend a large sum -- oh, I don't know, 20bn dollars? -- to instigate a programme to intercept and divert or destroy one with, say, a 1% risk of a collision with Earth, would anyone shout, "it's a scam to take taxpayer's money!"? More.

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