Dear all I think we should omit _at_1au because we can put it in the definition as a default and that will make the standard name more general, as Jim notes. We have other quantities defined that way, with a reference parameter that has a default which could be overridden by specifying a value. In the names originally proposed by Odele et al., the distance from the sun was specified in the definition, not in the standard_name.
So far no-one has expressed a view on whether we should change flux to flux_density in existing names. If we do that, then I think flux_density will be better than irradiance, because of consistency, if there is no essential distinction. On the other hand, if we stick with flux in all other names (for m-2 quantities) then we could use irradiance in these new names, because the proposers and others in their community would find a standard_name using flux for W m-2 to be misleading. Let's see what other views are contributed about "flux" versus "flux density". Best wishes Jonathan On Mon, May 18, 2015 at 03:54:07PM +0000, Odele Coddington wrote: > > Okay, thanks Jim. In this case, I would still support the standard names I > suggested earlier, but including the _at_1au suffix. > Best regards, > Odele > > From: Jim Biard <[email protected]<mailto:[email protected]>> > Date: Monday, May 18, 2015 at 8:48 AM > To: Odele Coddington > <[email protected]<mailto:[email protected]>>, > Judith Lean <[email protected]<mailto:[email protected]>>, > Jonathan Gregory <[email protected]<mailto:[email protected]>> > Cc: "[email protected]<mailto:[email protected]>" > <[email protected]<mailto:[email protected]>>, > "[email protected]<mailto:[email protected]>" > <[email protected]<mailto:[email protected]>>, Peter Pilewskie > <[email protected]<mailto:[email protected]>>, > Daniel Wunder - NOAA Affiliate > <[email protected]<mailto:[email protected]>>, > "[email protected]<mailto:[email protected]>" > <[email protected]<mailto:[email protected]>> > Subject: Re: [CF-metadata] New standard name requests for TSI and SSI > > Odele, > > If the _at_1au suffix is left off, I think we should definitely have the > distance of the reference surface provided as a coordinate variable as > Jonathan suggested. That would provide the most flexible definition for > future use, so we don't have to add yet another standard name if someone > comes along that wants to have a reference surface at 1 light year or 2 solar > radii, etc. > > Grace and peace, > > Jim > > On 5/15/15 11:30 AM, Odele Coddington wrote: > Hi all, > I had hesitated to chime in so late in the email exchange. But, as the keeper > of the CDR, here?s my take on it. > > I would highly be in favor of Jim Biard?s suggested names (with or without > the _at_1au suffix). As Judith mentioned, there?s no time like the present > to educate people. I don?t see any compelling reason why the standard names > of the CF group should differ from the standard names of constants, units and > uncertainty by the National Institute of Standards and Technology (NIST), or > the UK equivalent of NIST, with definitions supported by the International > System of Units (SI). For that reason, and despite what the convention of > usage is in the CF program, I can?t support the usage of ?radiative_flux? for > irradiance, because the units are simply incorrect. > > I note that the SI system, which has an international governing authority, > ?modifies the SI as necessary to reflect the latest advances in science and > technology? (http://physics.nist.gov/cuu/Units/international.html). > Surely, conventions can change since constants certainly have! > > Therefore, I support these name possibilities (with or without the _at_1au > suffix, as this can be adequately explained in the definition). II highly > favor the first pair: > > solar_irradiance > solar_irradiance_per_unit_wavelength > > solar_radiative_flux_density > solar_radiative_flux_density_per_unit_wavelength > > Best regards, > Odele Coddington > > From: Judith Lean <[email protected]<mailto:[email protected]>> > Date: Friday, May 15, 2015 at 9:00 AM > To: Jonathan Gregory > <[email protected]<mailto:[email protected]>>, Jim Biard > <[email protected]<mailto:[email protected]>> > Cc: "[email protected]<mailto:[email protected]>" > <[email protected]<mailto:[email protected]>>, > "[email protected]<mailto:[email protected]>" > <[email protected]<mailto:[email protected]>>, Odele Coddington > <[email protected]<mailto:[email protected]>>, > Peter Pilewskie > <[email protected]<mailto:[email protected]>>, > Daniel Wunder - NOAA Affiliate > <[email protected]<mailto:[email protected]>>, > "[email protected]<mailto:[email protected]>" > <[email protected]<mailto:[email protected]>> > Subject: Re: [CF-metadata] New standard name requests for TSI and SSI > > Dear Jonathan and JIm, > > I guess the argument favoring Jonathan?s terminology is that the > public/non-experts will understand solar radiative flux (density) more > readily than they will know what irradiance means? > I actually find this myself when speaking with reporters and giving public > lectures, for example - they prefer not to use the word irradiance since they > - nor their audience - are familiar with tit. Solar radiation or brightness > conveys more meaning to them, and I do tend to use these words more than > irradiance. > > Having said that - theres no time like the present to educate people. > Hence, I am happy with either of these ?common? names. Thanks to you both for > ?designing?them for us. > > Judith > ps > Odele - what do you think? ..you?re the keeper of the CDR! > Dan and Phil- from a NOAA perspective do you have a preference? > > > On May 15, 2015, at 10:33 AM, Peter Pilewskie > <[email protected]<mailto:[email protected]>> > wrote: > > I prefer irradiance. This is the solar irradiance climate data record, after > all! > > Peter > > On May 15, 2015, at 8:20 AM, "Jonathan Gregory" > <[email protected]<mailto:[email protected]>> wrote: > > Dear Judith and Jim > > Thanks for sticking with this process, Judith, though it may be hard work. > > Thanks for your ideas, Jim. I largely agree with your arguments and so largely > reach the same conclusions. There are two points on which we differ. > > * I prefer radiative_flux[_density] to irradiance because they mean the same, > essentially, as far as I can see, so it's better to use a phrase we already > have, for consistency. If we use a different one it might cause people to > suppose it's a different quantity. We do have standard_names for spherical_ > irradiance, but that's not the same thing, and radiance is different too - > it has different physical dimensions. > > * I didn't suggest _at_1au (or something like it) because it looks like a > coordinate, and we don't put coordinates in standard names. But, now I say > that, I wonder whether we should actually treat it as a coordinate. Could we > not simply say, in the definition, that this quantity applies at a distance of > one astronomical unit from the sun by default, but if a different distance is > intended, a coordinate variable of distance_from_sun (for instance - we need a > new standard name for it) should be supplied. That's a CF-like treatment. > > Best wishes > > Jonathan > > > -- > [CICS-NC]<http://www.cicsnc.org/>Visit us on > Facebook <http://www.facebook.com/cicsnc> Jim Biard > Research Scholar > Cooperative Institute for Climate and Satellites NC <http://cicsnc.org/> > North Carolina State University <http://ncsu.edu/> > NOAA National Centers for Environmental Information <http://ncdc.noaa.gov/> > formerly NOAA?s National Climatic Data Center > 151 Patton Ave, Asheville, NC 28801 > e: [email protected]<mailto:[email protected]> > o: +1 828 271 4900 > > We will be updating our social media soon. Follow our current Facebook (NOAA > National Climatic Data > Center<https://www.facebook.com/NOAANationalClimaticDataCenter> and NOAA > National Oceanographic Data Center<https://www.facebook.com/noaa.nodc>) and > Twitter (@NOAANCDC<https://twitter.com/NOAANCDC> and > @NOAAOceanData<https://twitter.com/NOAAOceanData>) accounts for the latest > information. > _______________________________________________ CF-metadata mailing list [email protected] http://mailman.cgd.ucar.edu/mailman/listinfo/cf-metadata
