Dear Richard
I think it is fine to encode these as a coordinate variable. In fact one of
reasons why CF bounds are (n,2) rather than (n+1) is so that the bounds can
overlap like yours do.
Best wishes
Jonathan
----- Forwarded message from "Hattersley, Richard" <richard.hattersley at metoffice.gov.uk> -----
> Date: Mon, 23 May 2016 12:40:31 +0000
> From: "Hattersley, Richard" <richard.hattersley at metoffice.gov.uk>
> To: "cf-metadata at cgd.ucar.edu" <cf-metadata at cgd.ucar.edu>
> Subject: [CF-metadata] Overlapping bounds on coordinate variable
>
> We have a dataset that represents accumulations from a single, common start time to successively later times. As such, the time values are unique, numeric, and monotonic (as required for a coordinate variable), but the time bounds all overlap:
>
> variables:
> float stratiform_rainfall_amount(dim0, grid_latitude, grid_longitude) ;
> stratiform_rainfall_amount:standard_name = "stratiform_rainfall_amount" ;
> ...
> int time(time) ;
> time:bounds = "time_bnds" ;
> ...
> int time_bnds(time, bnds) ;
> data:
>
> time = 1, 2, 3, 4, 5, 6 ;
>
> time_bnds =
> 0, 2,
> 0, 4,
> 0, 6,
> 0, 8,
> 0, 10,
> 0, 12 ;
>
> Is it recommended to encode these overlapping accumulations as a coordinate variable?
>
> In the most relevant prior discussion I have found (http://mailman.cgd.ucar.edu/pipermail/cf-metadata/2010/053823.html) the decision seems to hinge on whether the data have any "particular order" or whether it would "make sense to do an operation which depended on their being in order". In our case there definitely is an order and it does make sense to operate on them in that order.
>
> Richard Hattersley
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----- End forwarded message -----
Received on Mon May 23 2016 - 07:00:08 BST
