Hi All,
I've noticed some ambiguity in the CF document around the use of the
"cf_role" attribute which I think needs clarification.
In Appendix A it states that the *cf_role* attribute is valid for use on
a coordinate variable only, however, in virtually, if not all, the
examples in Appendix H cf_role is not attached to a coordinate variable.
E.g. H.2
dimensions:
station = 10 ; // measurement locations
time = UNLIMITED ;
variables:
float humidity(station,time) ;
humidity:standard_name = "specific humidity" ;
humidity:coordinates = "lat lon alt" ;
double time(time) ;
time:standard_name = "time";
time:long_name = "time of measurement" ;
time:units = "days since 1970-01-01 00:00:00" ;
float lon(station) ;
lon:standard_name = "longitude";
lon:long_name = "station longitude";
lon:units = "degrees_east";
float lat(station) ;
lat:standard_name = "latitude";
lat:long_name = "station latitude" ;
lat:units = "degrees_north" ;
float alt(station) ;
alt:long_name = "vertical distance above the surface" ;
alt:standard_name = "height" ;
alt:units = "m";
alt:positive = "up";
alt:axis = "Z";
char station_name(station, name_strlen) ;
station_name:long_name = "station name" ;
station_name:cf_role = "timeseries_id";
attributes:
:featureType = "timeSeries";
I think the cf_role variable "station_name" should be named by the
coordinates attribute for humidity.
Moreover, section 9.5 in the conventions document, 2nd paragraph, it
should say "Where feasible a coordinate or auxiliary coordinate variable
with the attribute cf_role should be included."
Assuming there are no objections I'll raise a defect ticket when Trac is
back.
Regards,
Ros.
_______________________________________________
CF-metadata mailing list
[email protected]
http://mailman.cgd.ucar.edu/mailman/listinfo/cf-metadata
