Dear Steve and Mark In view of the need for a reference level, it's part of the definition of the standard names that have units in decibels.
Cheers Jonathan ----- Forwarded message from Steven Emmerson <emmer...@ucar.edu> ----- > Date: Wed, 29 May 2013 09:25:59 -0600 > From: Steven Emmerson <emmer...@ucar.edu> > To: cf-metadata@cgd.ucar.edu > Subject: Re: [CF-metadata] dB decibel units > > Mark, > > Logarithmic units need a reference level in order to support numerical > conversions; "dB" doesn't have one. A decibel unit with a one milliwatt > reference level would be "0.1 lg(re 1 mW)". > > Regards, > Steven Emmerson > Software Developer > Unidata Program Center > University Corporation for Atmospheric Research > > > On Wed, May 29, 2013 at 4:31 AM, Hedley, Mark > <mark.hed...@metoffice.gov.uk>wrote: > > > Hello CF > > > > A few standard names: > > > > sound_intensity_level_* > > sound_pressure_level_* > > > > have a stated canonical units of dB. I think valid units in CF are > > defined by udunits2. > > > > My install of udunits (udunits2-2.1.24) does not recognise dB as a valid > > units string. > > > > Is this an issue for the CF standard names maintainers or for the udunits > > maintainers? > > > > thank you > > mark > > > > > > _______________________________________________ > > CF-metadata mailing list > > CF-metadata@cgd.ucar.edu > > http://mailman.cgd.ucar.edu/mailman/listinfo/cf-metadata > > > > > _______________________________________________ > CF-metadata mailing list > CF-metadata@cgd.ucar.edu > http://mailman.cgd.ucar.edu/mailman/listinfo/cf-metadata ----- End forwarded message ----- _______________________________________________ CF-metadata mailing list CF-metadata@cgd.ucar.edu http://mailman.cgd.ucar.edu/mailman/listinfo/cf-metadata
