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