tag:blogger.com,1999:blog-5337555368793819627.post6921919589311899820..comments2023-06-07T09:04:36.390-04:00Comments on More Grumbine Science: How to find climate normals?Robert Grumbinehttp://www.blogger.com/profile/10783453972811796911noreply@blogger.comBlogger12125tag:blogger.com,1999:blog-5337555368793819627.post-70000450088355181212011-08-07T14:48:38.127-04:002011-08-07T14:48:38.127-04:00Have you ever heard of labeling axes, giving units...Have you ever heard of labeling axes, giving units, or otherwise making it clear what you're talking about?Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-5337555368793819627.post-86624434537607972822011-08-04T23:32:14.838-04:002011-08-04T23:32:14.838-04:00:-) No, I hadn't. Thanks for the word. I...:-) No, I hadn't. Thanks for the word. I'm visiting family, so am not on net much. There's something karmic about how I post my most immediately attention-getting note right before leaving on vacation.Robert Grumbinehttps://www.blogger.com/profile/10783453972811796911noreply@blogger.comtag:blogger.com,1999:blog-5337555368793819627.post-83291741332549164192011-08-04T12:02:10.417-04:002011-08-04T12:02:10.417-04:00Hey Bob, did you see that Ezra Klein linked to you...Hey Bob, did you see that Ezra Klein linked to you in his WaPo Blog today?<br /><br />http://www.washingtonpost.com/blogs/ezra-klein/post/baby-its-not-particularly-cold-outside/2011/07/11/gIQAKwPDuI_blog.htmlPhilip H.https://www.blogger.com/profile/12049875206738422083noreply@blogger.comtag:blogger.com,1999:blog-5337555368793819627.post-76650840314908208652011-08-04T10:35:47.077-04:002011-08-04T10:35:47.077-04:00Thanks for the mention of Tamino's analysis. ...Thanks for the mention of Tamino's analysis. I've responded briefly at his place, and longer over here, in http://moregrumbinescience.blogspot.com/2011/08/is-it-really-normal.html<br /><br />No 'death blow' to my real point, but reason for caution regarding the lesser point of there being a change since ca. 1940.<br /><br />Stewart:<br />I hadn't seen the grist article, and it does indeed misrepresent my note pretty badly, as you say. It also replaced December 1976 with the year 1976, which is even more wrong -- I only ever looked at months (or multi-decades), not annual averages. Your comments there are good, and if you think it would be helpful, you're welcome to point people back to this comment of mine. They've got a registration thingie, which is a nuisance for me now, so commenting there myself is out for a while.<br /><br />Thinkprogress (Brad Johnson) did a better job and you're a little overcritical of them. Your comments are still mostly well-taken, though, so, again, if folks there are objecting to your points, aim them back here for my confirmation.<br /><br />To repeat, as you noticed and some don't seem to have: This post and method are not about attributing cause for changes, they are about trying to decide if we can even refer to a 'normal climate'. And, later, if so, when was it and what did it look like.Robert Grumbinehttps://www.blogger.com/profile/10783453972811796911noreply@blogger.comtag:blogger.com,1999:blog-5337555368793819627.post-61399922937426747872011-08-04T03:10:01.512-04:002011-08-04T03:10:01.512-04:00Grumbine: I really like this analysis technique. H...Grumbine: I really like this analysis technique. However, one can put your conclusions on a more quantitative footing. (As an aside, you probably know that tamino has criticized your analysis but not in a constructive way.) <br /><br />What we would have if there was no temperature trend would be a one dimensional random walk. In such a case, we expect roughly an accumulated sum of square root of N times the typical step size. N is the number of months and the typical jiggle is 0.2 degrees, so we could expect about 9 degrees for the cumulative sum after 2000 months. Tamino points out that this neglects autocorrelation: the fact that if say one month is hot, the next is very likely to be hot as well. The correlation function drops steeply for 10 months, then more slowly for 100 months: hard to summarize, but I think 25 months is a good number. This would multiply the figure above by square root of 25, giving 45 degrees accumulation. This sort of agrees with Tamino's second accumulated random number plot with autocorrelation.<br /><br />Here's the main point. Your cumulative sum curve is 300; much larger than 45. Moreover, your curve rises smoothly and does not exhibit the noise that a random number generated curve does.rick baartmannoreply@blogger.comtag:blogger.com,1999:blog-5337555368793819627.post-26334799475350162812011-08-04T02:22:24.625-04:002011-08-04T02:22:24.625-04:00see Tamino's latest on this; autocorrelation b...see Tamino's latest on this; autocorrelation befuddles.Hank Robertshttps://www.blogger.com/profile/07521410755553979665noreply@blogger.comtag:blogger.com,1999:blog-5337555368793819627.post-12116022138596517952011-08-04T00:24:13.952-04:002011-08-04T00:24:13.952-04:00You got the Tamino stats school on this one:
http...You got the Tamino stats school on this one:<br /><br />http://tamino.wordpress.com/2011/08/03/cumulative-sums/#comment-52890Rattus Norvegicushttps://www.blogger.com/profile/03449457204330125792noreply@blogger.comtag:blogger.com,1999:blog-5337555368793819627.post-14432838172232520492011-08-03T19:58:47.543-04:002011-08-03T19:58:47.543-04:00I think you should pay some attention to the fact ...I think you should pay some attention to the fact that the Hadley data from 1850 to around 1950 excludes most of the plant. There were NO measurements in all of Africa bar Cairo and Cape Town until around 1910, liekwise central America and Se Asia. These are all hot places, so the absolute Hadley averages are all understated. That might not matter if we can assume that the trends were globally identical, but were they?Tim Curtinhttp://www.timcurtin.comnoreply@blogger.comtag:blogger.com,1999:blog-5337555368793819627.post-29771021902549665322011-08-03T15:33:31.951-04:002011-08-03T15:33:31.951-04:00Hello,
thought you might find it interesting (or ...Hello,<br /><br />thought you might find it interesting (or distressing)that ThinkProgress and Grist have both put up posts utterly misrepresenting/oversimplifying this interesting and informative post. Grist has gone so far as to reduce it to "more than a quarter of the population (and statistically more people reading this, since it’s on the internet) really has no idea what the global climate would feel like if humanity hadn't been messing with it for more than a century."<br /><br />http://www.grist.org/list/2011-08-03-born-after-1976-youve-never-experienced-normal-global-temperatur<br /><br />and <br /><br />http://thinkprogress.org/green/2011/08/02/285660/people-under-35-have-never-seen-normal-global-temperatures/<br /><br />Maybe you can contact them and set things straight?Stewarthttps://www.blogger.com/profile/00228826715633338544noreply@blogger.comtag:blogger.com,1999:blog-5337555368793819627.post-4408490823798046862011-08-02T19:18:21.587-04:002011-08-02T19:18:21.587-04:00M: You illustrate why it is hazardous to make a si...M: You illustrate why it is hazardous to make a simple statement -- missing the many qualifiers that we'd normally have in a scientific paper. The assumptions are that temperatures are the only thing that matter (false) and that there was balance with respect to the reference temperature chosen (there wasn't) chose. In spite of those inaccuracies, I was hoping readers could come away with the idea that there is something meaningful about looking at cumulative temperature anomalies. <br /><br />The air conditioners were probably a better example.<br /><br />KenH:<br />Could be. This analysis doesn't say anything about what caused a change in the climate system. It does lend some strength to claims that there <i>has</i> been a change in the climate system. This might be no news to you, but it is to some others.<br /><br />A different post where I explore there being a change in the climate system in recent centuries is http://moregrumbinescience.blogspot.com/2010/01/co2-and-temperature-for-800000-years.htmlRobert Grumbinehttps://www.blogger.com/profile/10783453972811796911noreply@blogger.comtag:blogger.com,1999:blog-5337555368793819627.post-28570174234830041242011-08-02T18:37:09.372-04:002011-08-02T18:37:09.372-04:00"Something has been active since 1940 that wa..."Something has been active since 1940 that wasn't active before 1940."<br /><br />Maybe this?<br /><br />http://en.wikipedia.org/wiki/File:Global_Carbon_Emissions.svg<br /><br />KenHAnonymousnoreply@blogger.comtag:blogger.com,1999:blog-5337555368793819627.post-82459735155576271222011-08-02T08:44:17.855-04:002011-08-02T08:44:17.855-04:00"Further, let's suppose that glaciers wer..."Further, let's suppose that glaciers were all in balance in 1850. "<br /><br />I think you need to explicitly state that the glaciers are in balance _with the reference temperature_ in 1850. And the reference temperature is much higher than the 1850 temperature. <br /><br />-MAnonymousnoreply@blogger.com