Dear Martin and Michaela Thanks for your comments. If a non-zero threshold is sometimes used, I think it's a reasonable future-proofing extension that we might allow it here, although it's not yet been requested. I don't feel strongly either way. We could omit that complexity at the moment, but introduce the name with _excess and threshold later if required, and make the present name an alias.
I think mole_stomatal_uptake_of_ozone, suggested by Michaela, would be good because it indicates the sign convention. Best wishes Jonathan ----- Forwarded message from Michaela Hegglin Hegglin <[email protected]> ----- > Date: Thu, 19 Apr 2018 09:51:16 +0000 > From: Michaela Hegglin Hegglin <[email protected]> > To: Martin Juckes - UKRI STFC <[email protected]> > CC: Jonathan Gregory <[email protected]>, "[email protected]" > <[email protected]> > Subject: Re: [CF-metadata] Four standard names for the AerChemMIP data > request > > Dear Martin, Jonathan, > > > The generic quantity that AerChemMIP is interested in, Phytotoxic ozone > > dose, can be used with a non-zero threshold -- so there may be a > > requirement for this in the future, but for CMIP6 we only need the case of > > threshold=0. As you point out, we can simplify the CF metadata if we > > restrict ourselves to this case. I'd be happy with that approach. > > To my rather modest knowledge of plant physiology, the threshold in the POD > is not necessarily 0, but may be dependent on the plant type and depending on > its detoxification capacity. Hence is not necessarily 0. While CMIP6 may not > use the POD at other thresholds, the wider community has done so in the past > and may therefore ask what threshold was used for the variable output. To me > it would hence be more logical to have the threshold indicated in the name. > > > Looking at other CF names, I notice that we should be referring to the > > "_mole_flux_of_ozone_" rather than just the "ozone_flux" (to distinguish it > > from mass flux). > > Sounds like a very good idea to me too. > > > I'm not sure about the phrase "flux_into_stomata": the stomata are the > > holes in the leaves, what we really mean is into the plant through the > > stomata. I'm not sure if > > "integration_wrt_time_of_mole_flux_of_ozone_into_vegetation" would be > > specific enough; > > "integration_wrt_time_of_mole_flux_of_ozone_into_vegetation_through_stomata" > > looks a bit long, but may be justified for a specialised quantity like > > this, > > This is indeed a very long name. Is there a reason why not to simply name it > after how researchers use it, namely stomatal flux or stomatal uptake? The > full name could then read > integration_wrt_time_of_mole_stomatal_flux_of_ozone? Whether to put in the > ‘into_vegetation’ or ‘_with_threshold_0’ is possibly a matter of taste. > Since only plants have stomata it should be clear that it’s meant to be > vegetation, so not needed. > > Michaela > > > > > > > regards, > > Martin > > ________________________________ > > From: CF-metadata <[email protected]> on behalf of Jonathan > > Gregory <[email protected]> > > Sent: 18 April 2018 17:41 > > To: [email protected] > > Subject: [CF-metadata] Four standard names for the AerChemMIP data request > > > > Dear Martin > > > >> Proposed name: integral_wrt_time_of_stomatal_ozone_flux_excess > > > > I appreciate that not all fluxes have their sign convention mentioned in the > > name, but in the case of precipitation, for example, I think it's obvious - > > that's not quite so with ozone_flux, I would say - on reflection, I guess > > that plants don't ever produce ozone, so the flux should be into the > > stomata, > > but although it can be clarified in the definition, as you say, I feel it > > would > > be even better to choose a word in the standard name which indicates which > > way > > the flux is going e.g. flux_into_stomata. > > > > There are existing names containing mole_flux_of_SPECIES. This is one of > > those > > so it might be good to follow that pattern too. > > > > I see that pod0 has a threshold of zero. You're proposing something more > > general, which could support any threshold, but is the threshold ever going > > to be non-zero? If zero is the only possibility, it doesn't need to be > > described as an excess. > > > >> (3b) stomatal_ozone_flux_threshold [mol m-2 s-1] > >> > >> A standard name to be used on variable specifying a threshold value of > >> stomatal ozone flux. > > > > This quantity would be more generally useful if "threshold" was omitted. I'm > > aware there is an air_temperature_threshold in the table, but I see no > > reason > > why a quantity used as a threshold must have "threshold" in its name. > > > > Best wishes and thanks > > > > Jonathan > > _______________________________________________ > > CF-metadata mailing list > > [email protected] > > http://mailman.cgd.ucar.edu/mailman/listinfo/cf-metadata > ----- End forwarded message ----- _______________________________________________ CF-metadata mailing list [email protected] http://mailman.cgd.ucar.edu/mailman/listinfo/cf-metadata
