Two comments from UC on smoothing CET using Mannian smoothing, a technique peer reviewed by real climate scientists (though not statisticians). I think these coldish years do matter, maybe now there will be some advance in smoothing methods. mike writes (1062784268.txt) ( I think this is somewhat related to CET smoothing (?) ) The second, […]
load MBHsmooths1.txt % http://www.climateaudit.info/wp-content/uploads/2009/11/mbhsmooths1.txt % MBHsmooths1 = [ Year AnnualRecon Instrumental MB98SmoothTrick MBH98SmoothNoTrick MBH99SmoothTrick MBH99SmoothNoTrick ] [B98,A98]=butter(10,2/50); % ’50 year lowpass’ in98=MBHsmooths1(401:981,2); % Annual Recon MBH98, %source: % http://www.nature.com/nature/journal/v430/n6995/extref/FigureData/nhmean.txt , % col 2 Trick=MBHsmooths1(982:996,3); % pad with instrumental (1981..1995) .. % source: % http://www.nature.com/nature/journal/v430/n6995/extref/FigureData/nhmean.txt % col 3 out98t=flipud(filter(B98,A98,flipud([filter(B98,A98,[in98;Trick;zeros(100,1)])]))); %..then smooth % Note that filter.m initializes […]
Date: 16 Nov 1999, Phil I’ve just completed Mike’s Nature trick of adding in the real temps to each series for the last 20 years (ie from 1981 onwards) amd from 1961 for Keith’s to hide the decline. Date: 22 Dec 2004, mike No researchers in this field have ever, to our knowledge, “grafted […]
Let’s continue Mann 2008 – Replication with EIV. To run regreclow.m and regrechigh.m you’ll need files climate, eofnumb, and proxyN, where N runs from 1 to 19. I’ve run prepinputforrecon.m with required folder structure (C:\holocene\s1\zuz10\work1\temann\ etc.) in my computer. After that I did run regrechigh.m in folder C:\holocene\s1\zuz10\work1\temann\zzrecon1209\nhnhscrihad\highf and regreclow.m in folder C:\holocene\s1\zuz10\work1\temann\zzrecon1209\nhnhscrihad\lowf The regem […]
UC writes in that there’s another Mannian problem: And GRL08 ( http://www.meteo.psu.edu/~mann/shared/articles/MannGRL08.pdf ) is the prologue. Tried this new smoother ( http://www.meteo.psu.edu/~mann/smoothing08/lowpassadaptive.m ) with HadCRUT monthly and f=0.0104, [smoothedbest,w0,w1,w2,msebest] = lowpassadaptive(HadM, 0.0104); got this figure, But the weights are [w0 w1 w2] ans = 0.4100 0 0.5500 Surprisingly, this does not agree with the text, […]
%%%% Matlab version of Hockey Stick % %Mann, M. E., R. S. Bradley, and M. K. Hughes (1998), Global-scale %temperature patterns and climate forcing over the past six centuries, %Nature, 392, 779– 787. % %Mann, M. E., R. S. Bradley, and M. K. Hughes (1999), Northern %Hemisphere temperatures during the past millennium: Inferences, uncertainties, %and […]
I then compared verification statistics for the different reconstructions as shown below. OLS yielded much the “best” fit in the calibration period, but the worst fit in the verification period. If OLS is equivalent to ICE, it actually finds the best fit (minimizes calibration residuals), and in proxy-temperature case makes the most obvious overfit. Let […]
In calibration problem we have accurately known data values (X) and a responses to those values (Y). Responses are scaled and contaminated by noise (E), but easier to obtain. Given the calibration data (X,Y), we want to estimate new data values (X’) when we observe response Y’. Using Brown’s (Brown 1982) notation, we have a […]
There’s an interesting knock-on effect from the collapse of MBH98 Figure 7 (see here and here). See update from UC in May 2011 below in which he did a “bit-true” replication. We’ve spent a lot of time arguing about RE statistics versus r2 statistics. Now think about this dispute in the context of Figure 7. […]
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