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[netCDF #UBD-124546]: question on dBz

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  • Subject: [netCDF #UBD-124546]: question on dBz
  • Date: Tue, 09 Dec 2014 12:57:20 -0700
Hi,

> I am working on constructing metadata for a satellite data set packaged
> using netCDF format. We want it CF-compliant.
> 
> One of the variable is reflectivity profile with unit of 'dBz'. However,
> I could not find proper unit definition in UDUNITS.dat for this
> variable. Would you like to suggest what we should do to make the netCDF
> file CF-compliant and also describe the field correctly?

The original udunits package did not support logarithmic units such as dBZ,
but the current udunits (and all versions since 2.0.4) includes such support:

  http://www.unidata.ucar.edu/software/udunits/

"dBZ" is defined there as equal to "0.1 lg(re (1e-6 m)^3)", so
the reference level is included in the definition.  There is a 
CF standard name for the quantity "equivalent_reflectivity_factor"
which uses dBZ as its canonical units.

> Thanks for your help,

Your welcome!

> Xiang Li

--Russ

Russ Rew                                         UCAR Unidata Program
address@hidden                      http://www.unidata.ucar.edu



Ticket Details
===================
Ticket ID: UBD-124546
Department: Support netCDF
Priority: Normal
Status: Closed