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#95: Development of CF 1.5 Data Model
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  Reporter:  markh           |       Owner:  [email protected]
      Type:  task            |      Status:  new                          
  Priority:  medium          |   Milestone:                               
 Component:  cf-conventions  |     Version:                               
Resolution:                  |    Keywords:                               
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Comment (by bnl):

 Replying to [comment:72 pbentley]:
 > Hi David,
 >
 > > Global attributes apply to each data variable in the dataset, do they
 not?
 >
 > My current understanding is that this is not the case.
 >
 > AFAIK, the netcdf library does not implement this behaviour. And I'm not
 aware of any explicit statement within the CF specifation that says that
 global attributes routinely act as providers of default values in the case
 where a variable-scope attribute is absent. But I'm happy to be corrected
 if I've missed the salient bit of text.
 >
 > I'm fairly sure the netcdf tools I use (the usual suspects) don't rely
 on this behaviour. Could be wrong.

 The netcdf data model makes no assumption about what happens with file
 attributes as opposed to variable attributes, and so the netcdf libraries
 don't either. What we are dealing with here is the CF data model ... which
 I think we are clear on does imply that global attributes are inherited by
 variables ... the CF convention seems clear on that. Where there is any
 contention at all seems to be whether there is any semantic difference
 between such attributes on a variable ... does a variable need to know
 whether it inherited an atttribute from the file or in it's own right. My
 answer: No.

-- 
Ticket URL: <https://cf-pcmdi.llnl.gov/trac/ticket/95#comment:74>
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