Saturday, March 22, 2014

Paleo plotting - new draft climate plotter


In the previous post, in response to a challenge posed by Gavin at Real Climate for better ways of visualizing Phanerozoic climate data, I showed an interactive plot mechanism which could allow the user to easily vary the time scale in a single plot environment. The mechanics really come from the Moyhu climate plotter, and I've been meaning to work up a new version of that (and it's time to update with 2013 data).

A limitation in the V2 plotter was a restriction to annual data, and it generally covered the instrumental period. This reduced the data size, which is of some importance if all the data has to be downloaded. It also facilitates post processing - eg combining or smoothing series.

In V3 I've allowed all kinds of time data. I can overcome the size p[roblem by using XMLHTTPrequest, so only requested data is downloaded. And to allow the user to easily go from a century timescale to decade (for monthly data) or million years, I need to upgrade the user controls. Also to show monthly data, I will need an automatic updating system.

I'm posting a draft version here. It doesn't yet have request download, though download times are reasonable. And a lot of the post-processing doesn't yet work. Smoothing and regresion are patchy, and the calculate facility will probably go. But the basic plotting should work, and I'd be interested in comments, especially of datasets to include.


The basic mechanics are described in the plotter page. If you select from the menu, and then click the adjacent button, a plot will appear. You can control the axes with the blue and red arrow strips (new). Red for translate, blue for zoom. A smaller change if you click near the centre.  Zooming time holds the right hand time fixed. Times are in calendar years, so -10000 is 10000BCE. I'll probably rescale for big numbers, perhaps then using BP.

V2 allowed adjustment of temps to a common anomaly base. That's currently disabled. The data is shown as is.

The main self-documentation, as in V2,  is Ctrl-Click. Do that on any active element, and some help should appear in the bottom right window. If you click next to a selection box (for data), it will tell about the box; to ask about the dataset, you need to plot it, and then click on the "handle" button in the blue "Curves" pane.

There are now two pages of selection boxes. I've put what I think most interesting on front. They are color coded; red for monthly, green for the v2 annual data, and blue for paleo. I'm sure there will be issues with individual data sets - this is a draft. It will become a page when more things are ironed out. I'll keep the v2 page as I know people have linked to plots there.

So here is is:



11 comments:

  1. If you see fraud and do not say fraud, then you are a fraud. And you are Nick, you are.

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  2. Thanks Nick! Great tool and now upgraded with paleo! Free of charge! What is not to like?

    Dunno what the other chap's problem is. Drinking on an empty stomach perhaps? I've seen people turn nasty doing that.

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    1. Maybe he meant "frog"? If you see a frog, and do not say "frog", then you are a frog.

      As for this: "And you are Nick, you are" -- he seems to think it's important to reassure Nick that he is, in fact, Nick. Weird.

      Cheers, Ned.

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    2. You can't argue with the logic,or with Nigel Persaud's puppets.

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  3. Great job Nick. How come Loehle's reconstruction starts in the 20th C though ?
    Interesting to compare MBH98 to the more modern Lungqvist. It's hard to accept that this has "supported the broad consensus shown in the 1998 hockey stick graph" though.

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    1. Thanks, None. I added 1950 to the BP data to put it in calendar years. Looks like with Loehle, I assumed it was BP when it was already calendar. I'll fix.

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    2. Loehle fixed. I also found Ljungqvist had been displaced 50 years - fixed.

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    3. Is it possible that Ljungqvist is also backwards?

      Ned

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    4. Ned,
      Thanks, yes it is. I'll fix. Since there's a lot of data now, I tried an automatic rule to work out what needs to be reversed etc. So there may be others too.

      The output button (low right) works now. It gives a listing of the data that it plots.

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  4. Thanks! Nice tool and now upgraded with paleo!

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    1. Thanks, Daniel (and BBD)
      A few more things are working now. Regression is OK, I think, and smoothing, though the smoothing is formal - ie a 5-node boxcar plot averages 5 adjacent values, regardless of separation. This is OK for uniform timesteps, and most are uniform or near uinform.

      The Output button works and is useful for checking data.

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