Home > CRUTEMP, ERSST, GIStemp, HadSST, LSCF, Natural Variability, Statistics > Lines, Sines, and Curve Fittings 17 – More Morlets

Lines, Sines, and Curve Fittings 17 – More Morlets

2011 February 22

I combine my Hemispheric Land-Ocean Fourier hacks with the previous Morlet Wavelet imagery.

I think we can conclude that the ~60 period cycle is strongest in NH Land and weakest in SH Sea, is stronger in the last half of the 20th Century and weakest in the last half of the 19th Century.

There are indications of shorter period cycle in the Southern Hemisphere especially in GISTEMP. Also stronger in the last half of 20th C. Is this a feature of GISTEMP? Or a bug? Is this is a sparsity of data, quality of data issue? Or just the way it is with these quasi-periodic signals.

If I understand this correctly, the hatched regions in the above plots indicate areas where a “cone of influence” reduces confidence due to end-point issues. In other words, the periods examined are long enough to be extending past the end of the series.

I had to hack the wavelet.plot code in the dplR package. Easy enough, since the plot code was written in R itself. The new plot code is here: morlet.plot.R.

The code is here (cru)
and here (gis)
and here (ncdc)

  1. ob
    2011 February 23 at 1:53 am

    For some reason I’m not able to access the morlet.plot.R file?

  2. 2011 February 23 at 5:08 am

    Try right clicking and doing a ‘save as’

    I also made a copy with a *.txt suffix. Try this

    You can also just try poking into the directory

  3. DeWitt Payne
    2011 April 21 at 8:25 am

    There’s a new paper out on the AMO and NH temperature variation from Tsonis’ group. It’s discussed at Pielke,Sr.’s blog.

  1. 2011 February 25 at 8:14 am
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