Allow comments in coordinate variables

[ngalbraith]

Appendix A, Attributes, indicates that the 'comment' attribute may be used as a global attribute or for non-coordinate data variables. Its description states that it is for 'Miscellaneous information about the data or methods used to produce it.'

For in situ ocean data, certain information about the coordinate variables seems to belong in a comment; coordinate values have characteristics that should be described, but there are no standards for these descriptions yet.

For example, for a surface mooring, this seems like the best place to indicate whether the latitude and longitude are the surveyed anchor position or a GPS fix from the buoy itself, and whether the depth is the combined length of line/chain/instrument cases between the surface and the sensor, or a calculated depth based on measured pressure.

So, I propose that in the table in Appendix A we change the 'Use' of the comment attribute from G,D to G,C,D, to allow comments for variables containing coordinate data.

-Nan

[davidhassell]

As there have been no comments for ​three weeks, I think we can accept this defect.

David