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Introduce the newly chosen standard name

Open mraspaud opened this issue 2 months ago • 7 comments

As we have discussed in https://github.com/orgs/cf-convention/discussions/429, to be accurate, Satpy should not name quantities not normalised with the sun zenith angle as "toa_bidirectional_reflectance".

We thus need to introduce a new standard name in satpy for these quantities. It might take while to get an official standard name in the cf conventions, so for now we are going to go for ~"oblique_toa_bidirectional_reflectance"~ "product_of_cosine_solar_zenith_angle_and_toa_bidirectional_reflectance", and use that until an official standard name is adopted.

Here are some of the to-do items we have identified so far.

  • [ ] Decide on something to use for now
  • [ ] Update base reader class to overwrite standard_name if “sunz_corrected” modifier is not present
  • [ ] Update enhancer to detect old standard name being matched and absence of “sunz_corrected” modifier and produce warning
  • [ ] Add satpy.config feature flag for pseudo-reflectance standard name to be False by default in 0.60, True in 1.0.
  • [ ] Copy all existing “toa_bidirectional_reflectance” enhancements with the new standard name for pseudo-reflectance since they are used interchangeably right now

mraspaud avatar Oct 22 '25 09:10 mraspaud

so for now we are going to go for "oblique_toa_bidirectional_reflectance",

That's not how I understood yesterdays discussion. I understood that "oblique_toa_bidirectional_reflectance" was a candidate for the calibration name, not for the standard name. It's possible that I misunderstood.

gerritholl avatar Oct 22 '25 10:10 gerritholl

oblique_toa_bidirectional_reflectance is my candidate as the standard name in https://github.com/orgs/cf-convention/discussions/429#discussioncomment-14616050

pnuu avatar Oct 22 '25 10:10 pnuu

My understanding was that an executive decision should be made to choose the standard name, and that I needed to be the one making decision. As we go for "oblique_reflectance" for calibration, and that I like short names better (see my latest comment in the mentioned cf discussion), I decided to go for @pnuu 's standard name proposal to fulfil both my criteria.

mraspaud avatar Oct 22 '25 10:10 mraspaud

Today is the first time I have seen the oblique_toa_bidirectionar_reflectance proposal — I don't think we discussed it with Jon Gregory in the September conversation, where we narrowed it down to a shortlist with two candidates. My intention with the "executive decision" proposal yesterday was between those two, not to reopen the discussion with entirely new proposals. 🤷

gerritholl avatar Oct 22 '25 11:10 gerritholl

I think what I said yesterday was, "we have two candidates, we need an executive decision". I didn't know we had more than two candidates.

gerritholl avatar Oct 22 '25 11:10 gerritholl

Side note: Jon Gregory had suggested that the super long name ratio_of_product_of_toa_outgoing_radiance_per_unit_wavelength_and_pi_by_solar_irradiance_per_unit_wavelength could be shortened if you remove the "per_unit_wavelength" making it:

ratio_of_product_of_toa_outgoing_radiance_and_pi_by_solar_irradiance

But I'm not sure that was accepted by @pdebuyl and it still includes the ugly "pi".

djhoese avatar Oct 22 '25 11:10 djhoese

Ok, I didn't realise going for "oblique_toa_bidirectional_reflectance" would be controversial, so let's pick the shortest of the two others for now : product_of_cosine_solar_zenith_angle_and_toa_bidirectional_reflectance

mraspaud avatar Oct 22 '25 11:10 mraspaud