Difference between revisions of "CF"

From Federation of Earth Science Information Partners
 
(15 intermediate revisions by 4 users not shown)
Line 1: Line 1:
=The CF Standards Cluster=
+
=The CF Conventions Cluster=
  
==Objectives==
+
Information about the Climate Forecast Conventions has moved to [[:Category:Climate Forecast Conventions | Climate Forecast Conventions]].
:Propose extensions to the CF naming conventions that are relevant to observational data
 
:Create use cases and interoperability demos that demonstrate the value of CF usage in remote sensing
 
:Provide tutorials at Federation meetings on the use of the CF conventions
 
  
==Get Involved: Monthly Telecons==
+
[[Category:CollabArea]][[category:Climate Forecast Conventions]]
:Next telecon:
 
::Monday Dec 12, 3pm ET / 12noon PT
 
::Dial: 877-668-4493
 
::Access code: 23138379
 
::Agenda:
 
:::Winter Meeting Plans
 
:::Selection of Cluster Chair
 
 
 
:Minutes of past telecons/meetings:
 
 
 
== Possible CF Extensions ==
 
:1. Spectral bands
 
::Define as dimension rather than coordinate variable
 
::Pre-define band names
 
::Pre-define by wavelength/frequency range
 
 
 
:2. Data quality
 
::Modifiers such as "percent_cloud_free"
 
 
 
:3. Swath geometry
 
::Orbital parameters
 
 
 
:4. Engineering parameters
 
::Calibration tables
 
 
 
== CF-Aware Tools ==
 
 
 
==Spectral Band Proposal by Tom Whittaker==
 
Create standard_names that can be recognized by applications as
 
being the special "band dimension" variable (similar to "time").
 
The name of this dimension variable would not, however, be specified,
 
but inferred from its attributes.
 
 
 
Create two coordinate axis types ("wavelength" and "wavenumber")
 
that can be recognized by the NetCDF library as defining a "spectral
 
coordinate".
 
 
 
Thus, the band dimension might be declared:
 
 
 
:<variable name="band" shape="band" type="float" >
 
::<attribute name="standard_name" value="wavelength" />
 
::<attribute name="units" value = "cm" />
 
::<attribute name="_CoordinateAxisType" value = "wavelength" />
 
:</variable>
 
 
 
The dimension variable can then be used to dimension arrays associated
 
with the spectral channels, e.g., wavelength boundaries for each band
 
(channel), units, scaling, etc.  The use of these (dimensioned)
 
variables, however, would be up to the application developers rather
 
than made part of the conventions, per se.
 
 
 
This would necessitate creating perhaps two new standard_names:
 
 
 
'''wavelength''' (there is already a "radiation_wavelength" with
 
"electromagnetic_wavelength" as an alias, but I don't see an
 
issue for making just "wavelength" a standard name, either.  I also
 
recognize that in most cases this refers to the center wavelength of
 
the band/channel, and perhaps should be so designated...?).
 
 
 
'''wavenumber'''  (There is no equivalent standard_name.  Again, I imagine this would actually refer to a center wavenumber).
 
 
 
We would also then need to define two new coordinate axis types:
 
wavelength and wavenumber.
 
 
 
For the case where people don't or can't use the dimension variable as
 
a coordinate variable, we recommend that they use the convention name
 
"band" as the dimension variable so that applications can at least
 
recognize this for what it is.
 
 
 
In all cases, new (dimensioned) variables could then be used to
 
specify band-specific attributes.  For example:
 
 
 
:<variable name="minimum_wavelength" shape="band" type="double">
 
::<attribute name="units" value="cm" />
 
:</variable>
 
 
 
== Join the Cluster e-mail list ==
 
:http://www.lists.esipfed.org/mailman/listinfo/esip-cf
 
 
 
== External Links ==
 
:CF Home Page
 
http://cf-pcmdi.llnl.gov
 
:Read the CF-satellite archives (UCAR):
 
http://www.unidata.ucar.edu/mailing_lists/archives/cf-satellite
 
:Join the CF-satellite e-mail list (UCAR):
 
http://mailman.unidata.ucar.edu/mailman/listinfo/cf-satellite
 
 
 
== Governance ==
 
Interim Chair: Rob Raskin  raskin at jpl.nasa.gov
 
 
 
[[Category:CollabArea]]
 

Latest revision as of 17:00, 23 April 2012

The CF Conventions Cluster

Information about the Climate Forecast Conventions has moved to Climate Forecast Conventions.