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Global Air Temps

Discussion in 'Environmental Discussion' started by tochatihu, Nov 7, 2014.

  1. bwilson4web

    bwilson4web BMW i3 and Model 3

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    I see the difference:
    There are two, possibly three approaches to posting an image. Two involve including the image file as part of the posting and the one I use is a reference to the image at another web site. My experience suggests there is some disk quota for attachments or included files. Regardless, this image shows some evidence of Nyquest sampling:
    [​IMG]
    Assuming a fixed, 11 year solar cycle sampled every 10 years, the minimum and maximum would have an ~5-6 year period in the sampled data. If the 11 year solar cycle is not so fixed, the behavior under a fixed sampling interval could lead to artifacts.

    I would be happier to see summaries over the solar, minimum-to-minimum intervals. However, in spite of the potential Nyquest sampling error, I wouldn't toss out the obvious inference. So when did the satellite records start? <grins>

    Bob Wilson
     
  2. tochatihu

    tochatihu Senior Member

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    In the current sunspot cycle we are about 1/4 (or 1/3) after the peak. I found the comparable month in previous SS cycles, and took the average T over each one. This means the end of SS cycle 23 is grouped with SS cycle 24 through October. This is not ideal, but necessary to include the most recent data. Other thing to bear in mind is that as SS cycles are of somewhat uneven lengths, so are the averages.

    The main 2 differences in the SS cycle approach are that the 1934-1964 (decadal) decline is flat. That the more recent increases are all almost the same size. Implying a constant rate of T increase over the period, through Oct 2014. even though the magnitude of SS cycle 24 is about half of SS 23. Notable because 'some said' a weak SS cycle should be cooler. Not this time.

    The Nov 2014 global T must be available somewhere...