I have proposed a point obs standard to CF here:
http://cf-pcmdi.llnl.gov/trac/ticket/37
http://cf-pcmdi.llnl.gov/trac/wiki/PointObservationConventions
Feedback would be appreciated, as we'd like to start swimming
if we dont sink ;^)
This proposal (when accepted) will supercede the "Unidata
Observation Dataset Convention". We are looking at being able
to encode some of the NWS obs data stream, as it comes in on
the IDD. If there are specific requirements you have, send
them along and we will include them in our use cases.
I am not sure where is the best place to post this
question/coment, so I am starting with you. I am trying to
produce CF compliant NetCDF files for NASA's DISCOVER-AQ
airborne campaign. Specifically, I have a collection of
profiles from "aircraft spirals" around fixed locations which
have been binned at a fixed vertical grid. The natural way to
index the data is:
data(profile,altitude)
with coordinates:
longitude(profile)
latitude(profile)
time(profile)
but
altitude(altitude) // vertical grid is the same for
*all* profiles.
None of the CF feature types described in this word
document
seems to cover this case. The closest is "trajectory" but
it has no provision for vertical coordinates and my time
coordinate is certainly *not* monotonic. To describe the data
I'd need something like:
|
griddedProfile
|
a generic
collection of profile features on a fixed
vertical grid; time is not necessarily
monotonic.
|
|
data(i,p)
|
x(p) y(p) z(i)
t(p)
|
BTW, this same data structure would also be needed for the
airborne HSRL LIDAR data.
As for my feedback on the current CF draft. I find this
notion of "featureType" a bit awkward, given that you may need
a large number of permutations to cover all use cases. In
particular, the mandatory space-time coordinates is
problematic. While requiring (x,y,z,t) coordinates is OK,
requiring that they are dimensioned a certain way is too
restrictive, specially because this information is easily
discoverable. For example, if this restriction would be
lifted, the featureType "profile" could be used to describe my
data.
Thank you!
Arlindo
