tag:blogger.com,1999:blog-2313427464944392482.post6257896594332191612..comments2024-03-25T05:30:23.847+11:00Comments on HotWhopper: Anthony Watts' #AGU15 poster on US temperature trendsSouhttp://www.blogger.com/profile/08818999735123752034noreply@blogger.comBlogger64125tag:blogger.com,1999:blog-2313427464944392482.post-60523440148107151212016-02-08T05:22:56.821+11:002016-02-08T05:22:56.821+11:00Empirical demonstration that adjusted historic tem...Empirical demonstration that adjusted historic temperature station measurements are correct, because they match the pristine reference network: Evaluating the Impact of Historical Climate Network Homogenization Using the Climate Reference Network, 2016, Hausfather, Cowtan, Menne, and Williams. http://www-users.york.ac.uk/~kdc3/papers/crn2016/background.htmlTom Daytonhttps://www.blogger.com/profile/14033524810322903771noreply@blogger.comtag:blogger.com,1999:blog-2313427464944392482.post-78559008591030052952015-12-31T03:39:34.103+11:002015-12-31T03:39:34.103+11:00Eeeevvaaaaaannnnnn, where aaaaaare you?Eeeevvaaaaaannnnnn, where aaaaaare you?KatyDnoreply@blogger.comtag:blogger.com,1999:blog-2313427464944392482.post-56737103175473142772015-12-24T06:45:55.557+11:002015-12-24T06:45:55.557+11:00Cabc - if you read through all the old threads at ...Cabc - if you read through all the old threads at various sites that followed the 2012 'Breaking News' and subsequent abortion, you'll find Evan Jones somewhere remarking upon 2010 as the genesis. <br /><br />So, 2 years to put the original together and 3 1/2 more since then.<br /><br />By the time they're finished they'll have an article for a paleo-climate journal :)Kevin O'Neillhttps://www.blogger.com/profile/06692943768484857724noreply@blogger.comtag:blogger.com,1999:blog-2313427464944392482.post-38991919428953610102015-12-24T06:06:50.020+11:002015-12-24T06:06:50.020+11:00Considering the data only go to 2008, I feel it sh...Considering the data only go to 2008, I feel it should be asked: have they been working on this for six years? Three years of work before their initial lost at WUWT only to find that they had done it all wrong, then another three to get to where they are now - a poster session and a paper that may or may not be accepted to a journal? I cant imagine what happens if another fatal flaw is found that undermines their conclusions. And let's be honest, it's far more likely that they don't know what they are doing that it is that NOAA doesn't.<br /><br />Cabc Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-2313427464944392482.post-42777865340154548772015-12-23T20:10:44.828+11:002015-12-23T20:10:44.828+11:00Hi Sou
I'm really struggling to get on the sa...Hi Sou<br /><br />I'm really struggling to get on the same wavelength as Watts - I'm not sure what that says about my skill set. Anyway, is it correct to re-interpret the narrative as saying that the warmer the temperature (trend) the greater the anomaly between Watts and NOAA should be?<br /><br />Testing the second half of the data set, or the data set from 1999 onwards, shows little to no correlation between the NOAA (or Watts) temperatures and the actual anomaly.<br /><br />Maybe I've had a busy week (haven't we all) and I've totally missed the point. Wise counsel is sought!<br /><br />GeorgeGeorge Bailleynoreply@blogger.comtag:blogger.com,1999:blog-2313427464944392482.post-53644066744908017162015-12-23T18:43:38.023+11:002015-12-23T18:43:38.023+11:00OT Sou: Judicial watch in the USA is suing NOAA be...OT Sou: Judicial watch in the USA is <a href="https://www.washingtonpost.com/news/federal-eye/wp/2015/12/22/judicial-watch-sues-government-for-records-in-global-warming-dispute/" rel="nofollow">suing</a> NOAA because they didn't get what they wanted in an FOIA. I'm not familiar with Tom Fitton, but it might prime material for a post. Chase Shttps://www.blogger.com/profile/04659478289426350280noreply@blogger.comtag:blogger.com,1999:blog-2313427464944392482.post-36717827358175847052015-12-23T02:04:48.951+11:002015-12-23T02:04:48.951+11:00I think Gerlich and Tscheuschner is somewhat above...I think Gerlich and Tscheuschner is somewhat above and beyond even this. Their, uh, idiosyncracies extended far beyond mere mathturbation and deep into the realm of "not-even-wrong" conceptual confusion. It requires a staggering level of basic misunderstanding to reach the conclusion that the greenhouse effect cannot exist because it violates the Second Law of Thermodynamics!<br /><br /> palindromnoreply@blogger.comtag:blogger.com,1999:blog-2313427464944392482.post-21762048160636206532015-12-22T16:49:49.971+11:002015-12-22T16:49:49.971+11:00*crickets**<i>crickets</i>*billnoreply@blogger.comtag:blogger.com,1999:blog-2313427464944392482.post-38408170285994681782015-12-22T13:19:50.821+11:002015-12-22T13:19:50.821+11:00I bet a lot. It reminds me of the mathturbation in...I bet a lot. It reminds me of the mathturbation in <a href="http://scienceofdoom.com/2010/04/05/on-the-miseducation-of-the-uninformed-by-gerlich-and-scheuschner-2009/" rel="nofollow">Gerlich and Tscheuschner.</a>Chase Shttps://www.blogger.com/profile/04659478289426350280noreply@blogger.comtag:blogger.com,1999:blog-2313427464944392482.post-19068738276743022352015-12-22T11:22:45.610+11:002015-12-22T11:22:45.610+11:00In retrospect, I think Bernard gets +1 internets f...In retrospect, I think Bernard gets +1 internets for that observation :-)Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-2313427464944392482.post-50766213241793104102015-12-22T09:18:25.069+11:002015-12-22T09:18:25.069+11:00I kind of wonder how many variations on these meth...I kind of wonder how many variations on these methods they had to try before they got the results the desired. RobHhttps://www.blogger.com/profile/05953061681658403047noreply@blogger.comtag:blogger.com,1999:blog-2313427464944392482.post-2871110485858503012015-12-21T15:13:26.772+11:002015-12-21T15:13:26.772+11:00Millicent, similarly if the the collection of stat...Millicent, similarly if the the collection of stations they came up with had the Southeastern US overrepresented that would impart a cooling bias on their dataset. But of course, they aren't telling us yet.Rattus Norvegicushttps://www.blogger.com/profile/03449457204330125792noreply@blogger.comtag:blogger.com,1999:blog-2313427464944392482.post-27714181854643956182015-12-21T13:13:26.114+11:002015-12-21T13:13:26.114+11:00This comment has been removed by the author.Rattus Norvegicushttps://www.blogger.com/profile/03449457204330125792noreply@blogger.comtag:blogger.com,1999:blog-2313427464944392482.post-85137648137967615102015-12-21T09:26:24.817+11:002015-12-21T09:26:24.817+11:00That is a nice way of analysing the data. However,...That is a nice way of analysing the data. However, both curves should estimate the same quantity (if Watts et al did their averaging right) and you can thus also test the slope of the difference time series and whether this is different from zero. I did not compute a formal test, but by eye you can see that the trend of the difference time series is statistically significant. <br /><br />Not sure if a model with a change in the trend is justified, more likely the simpler model of just a linear trend would be more parsimonious, but maybe we could say that there is a "hiatus" since 1995, a "hiatus" in the meaning of the climate "debate": a non-significant change in trend that makes the trend since 1995 basically zero.Victor Venemahttps://www.blogger.com/profile/02842816166712285801noreply@blogger.comtag:blogger.com,1999:blog-2313427464944392482.post-76970485575759705432015-12-21T09:08:02.957+11:002015-12-21T09:08:02.957+11:00That is funny. I first thought you had made and er...That is funny. I first thought you had made and error, but the unit of the y-axis of the Watts et al graph really is 0.01*°C / decade. Do they mean 0.001 °C?<br /><br />°C per decade is the unit of the trend. To compute a trend you need to define the period. Trough these trend values, they draw a trend. ???Victor Venemahttps://www.blogger.com/profile/02842816166712285801noreply@blogger.comtag:blogger.com,1999:blog-2313427464944392482.post-56263047139707943912015-12-21T08:38:53.320+11:002015-12-21T08:38:53.320+11:00The other alternative headline is:
Anthony Watts ...The other alternative headline is:<br /><br />Anthony Watts says raw US data has a cooling bias.<br /><br />In the "raw" data, the "unperturbed" subset has a trend in the mean temperature of 0.204°C per decade; see table below. In the "perturbed" subset the trend is only 0.126°C per decade. That is a whooping difference of 0.2°C over this period. This confirms that in the USA the inhomogeneities ("perturbations") cause a cooling bias. Victor Venemahttps://www.blogger.com/profile/02842816166712285801noreply@blogger.comtag:blogger.com,1999:blog-2313427464944392482.post-2050617890133924202015-12-21T08:32:13.142+11:002015-12-21T08:32:13.142+11:00Occam's Razor tells me that the MMTS systemic ...<i>Occam's Razor tells me that the MMTS systemic bias is *still* evident in the results of Watts et al. It may be that they've scored an 'own goal' by showing that a *larger* MMTS bias adjustment needs to be made to completely remove the effects of the physical response curve of the Dale/Vishay thermistor.</i><br /><br />Agree. Just spent a large chunk of this afternoon reading Hubbard et. al. 2004:<br /><br />http://www.homogenisation.org/files/private/WG1/Bibliography/Applications/Applications%20%28F-J%29/hubbard_etal.pdf<br /><br />And that would seem to be where the cooling bias is coming from. Show us yer data, Wattsy.Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-2313427464944392482.post-56258645353738967152015-12-21T03:53:12.789+11:002015-12-21T03:53:12.789+11:00"It's trivially obvious from the charts t..."It's trivially obvious from the charts that there is no difference in trend, but you can test this statistically using this simple, well-understood procedure."<br /><br />Yes, doing just that with George Bailey's approximation of the data above, a simple linear regression with interaction (slope and intercept dummy variables) yields p=.908 for the difference in intercepts, and p=.355 for the difference in slopes. That is, neither difference is distinguishable from noise.<br /><br />However, if you *require* both lines to have the same origin at 1979, then the slopes are different (p=.047). Of course that result is an artifact.L Hamiltonhttps://www.blogger.com/profile/08402287979212116506noreply@blogger.comtag:blogger.com,1999:blog-2313427464944392482.post-31551139366878468332015-12-21T00:23:51.348+11:002015-12-21T00:23:51.348+11:00As a service to the HotWhopper community - I prese...As a service to the HotWhopper community - I present the digitised CAT 1,2 (0.204 degree per decade trend) and NOAA (0.323 degree per decade trend) data as derived from the plot above.<br /><br />Note that units are degrees C per decade.<br /><br />yyyy,wuwt,noaa,diff<br />1979, 0.00, 0.00, 0.00<br />1980, 0.83, 0.80, 0.03<br />1981, 1.18, 1.13, 0.05<br />1982, 0.23, 0.28, -0.05<br />1983, 0.52, 0.56, -0.04<br />1984, 0.47, 0.59, -0.12<br />1985, 0.10, 0.23, -0.13<br />1986, 1.18, 1.36, -0.18<br />1987, 1.22, 1.37, -0.15<br />1988, 0.77, 0.92, -0.15<br />1989, 0.33, 0.50, -0.17<br />1990, 1.32, 1.46, -0.14<br />1991, 1.17, 1.25, -0.08<br />1992, 0.70, 0.90, -0.20<br />1993, 0.00, 0.21, -0.21<br />1994, 0.83, 1.08, -0.25<br />1995, 0.71, 0.94, -0.23<br />1996, 0.21, 0.50, -0.29<br />1997, 0.47, 0.75, -0.28<br />1998, 1.60, 1.88, -0.28<br />1999, 1.34, 1.62, -0.28<br />2000, 0.96, 1.27, -0.31<br />2001, 1.23, 1.51, -0.28<br />2002, 0.92, 1.30, -0.38<br />2003, 1.03, 1.29, -0.26<br />2004, 0.94, 1.23, -0.29<br />2005, 1.11, 1.51, -0.40<br />2006, 1.55, 1.86, -0.31<br />2007, 1.30, 1.51, -0.21<br />2008, 0.38, 0.71, -0.33<br /><br />My British standard calibrated eyeball, together with a little help from excel, determined average differences of 0.00 for 1979-83, -0.14 for 1984-91, and -0.28 for 1992-08. Some-one with skill is likely to do a professional break-point analysis of the data.<br /><br />George<br />George Bailleynoreply@blogger.comtag:blogger.com,1999:blog-2313427464944392482.post-77553362285674186372015-12-20T18:42:01.551+11:002015-12-20T18:42:01.551+11:002008 seems to be a dangerous year to be using with...2008 seems to be a dangerous year to be using with a limited number of stations. If their method produces biases towards <a href="http://data.giss.nasa.gov/cgi-bin/gistemp/nmaps.cgi?sat=4&sst=6&type=anoms&mean_gen=0112&year1=2008&year2=2008&base1=1979&base2=1979&radius=1200&pol=rob" rel="nofollow">data from Alaska they could even show global cooling</a>.Millicentnoreply@blogger.comtag:blogger.com,1999:blog-2313427464944392482.post-15253135910153046322015-12-20T17:20:51.803+11:002015-12-20T17:20:51.803+11:00Apparently they calculate the anomalies, then adju...Apparently they calculate the anomalies, then adjust the graphs up or down so they coincide at 1979<br /><br />" we baselined it to 1979. If you don’t baseline it, the trends form an X rather than a <. ~ Evan"<br /><br />This implies that if all were graphed agains the same baseline, that the 1979 set of 92 stations would have a higher anomaly than the USHCN, and then that difference would diminish over the 30 year period as it rose more slowly, ending up below the USHCN level in 2008.<br /><br />Also just because a subset of stations has a different trend does not prove that the overall trend is incorrect. There can be various reasons for the difference.Anonymoushttps://www.blogger.com/profile/12083190014669867976noreply@blogger.comtag:blogger.com,1999:blog-2313427464944392482.post-26868106869965565922015-12-20T16:06:01.860+11:002015-12-20T16:06:01.860+11:00To me it's really a matter of Occam's Razo...To me it's really a matter of Occam's Razor: We have a statistical result that requires a physical explanation that exaggerates both highs and lows.<br /><br />There is *already* a known component of the measurement system that does exactly that - the Dale/Vishay 1140 thermistor used in MMTS stations.<br /><br />The systemic bias from the MMTS is corrected by the PHA process (supposedly). But we also know that this correction works *in aggregate* over all the COOP stations. <br /><br />Occam's Razor tells me that the MMTS systemic bias is *still* evident in the results of Watts et al. It may be that they've scored an 'own goal' by showing that a *larger* MMTS bias adjustment needs to be made to completely remove the effects of the physical response curve of the Dale/Vishay thermistor.Kevin O'Neillhttps://www.blogger.com/profile/15751040367339659805noreply@blogger.comtag:blogger.com,1999:blog-2313427464944392482.post-34001195221674837072015-12-20T15:37:29.481+11:002015-12-20T15:37:29.481+11:00I don't know if Evan Jones is going to bother ...I don't know if Evan Jones is going to bother getting any tips from this thread, but if he does come back, I would just like to point out the following ...<br /><br />Rather than just presenting trends, you can compare difference in trends between site quality categories with a simple linear regression with interaction terms. This will enable you to identify whether tehre is a significant difference in trend and by how much, and also to see if there is a difference in level. It's trivially obvious from the charts that there is no difference in trend, but you can test this statistically using this simple, well-understood procedure.<br /><br />Then you can publish a definitive paper putting to bed the idea that UHI has any effect on temperature trends.<br /><br />Looking forward to it!Captain Flashheartnoreply@blogger.comtag:blogger.com,1999:blog-2313427464944392482.post-81930996217404997742015-12-20T15:27:01.449+11:002015-12-20T15:27:01.449+11:00KR - I agree that "heat-sink" in this co...KR - I agree that "heat-sink" in this context is merely a euphemism for: We don't understand the physics. I've said as much in the comment section at WUWT.<br /><br />Give some credit to Evan Jones, though. Read through the comments (search the page for "evanmjones") and you'll find Evan consistently shooting down the usual suspects with their usual accusations of fraud/incompetence/conspiracy etc. He's also been shooting down the UHI meme at the same time.<br /><br />Evan will readily admit he doesn't know the physics - but his lack of understanding (of physics) here is a big detriment. When I find an unphysical result in a process I thought I understood, I know almost *immediately* that it is my understanding that is incorrect - not basic physics :)<br /><br />This doesn't mean their results are wrong, per se, it's their understanding of *why* the results are what they are that is wrong. Given the various plausible explanations, I suspect that like Fall et al this could be another 'own goal' :)Kevin O'Neillhttps://www.blogger.com/profile/15751040367339659805noreply@blogger.comtag:blogger.com,1999:blog-2313427464944392482.post-50523655696196412132015-12-20T14:51:28.990+11:002015-12-20T14:51:28.990+11:00Heat sinks?
The only possible effect of significa...Heat sinks?<br /><br />The only possible effect of significant heat sinks near recording stations would be to reduce the diurnal temperature range (DTR), the distance between min and max daily temps. They would have no effect _whatsoever_ upon trends. Seasonal variation is far larger than yearly climate change, meaning the time constant for such heat sinks is far less than a year - which is only reasonable given _basic_ physics. <br /><br />UHI influence on temperature trends is a dead horse. Unfortunately, that doesn't seem to stop Watts and Evans from beating the bloody (coagulated?) corpse. KRnoreply@blogger.com