Dear Jonathan, I think it would be better to gently deprecate `gregorian`, since the Bureau International des Poids et Mésures, who apparently have some influence in this area, define the Gregorian calendar to include leap seconds. A name such as `gregorian_fixed`, meaning "Gregorian with fixed length days" might work.
I think you are missing the fact that Jim would like there to be a defined mapping from the true UTC calendar to the fixed day calendar and back. I'm still of the opinion that we cannot define such a mapping in CF. The situation is analogous, in some ways, to the use of the `no_leap` calendar in climate simulations of the 20th century. In such cases there is a mapping from the calendar with 365 days years to the real world dates. There may even be an ideal one, which matches the mapping used by the modelling group to transfer real world forcing into the artificial calendar (this matches, I think, Jim's use case in which observations are transferred into an artificial calendar with no leap seconds). However, CF, has nothing to say about how you get from one calendar to another because there are too many use-case specific options available. Because the fixed day calendar is artificial, I think it is important not to refer to the time stamp as UTC --- it is a ISO8601 format time-stamp, as for the other artificial calendars. I've already suggested in another thread that we need to clarify the wording in the convention to make it clear that while the units of measure in the units string have (apart from a few exceptions) the meaning given to them by UDUNITS, the time-stamp only has the format used by UDUNITS and may have a different meaning depending on the calendar (this is sort of obvious, but not well expressed in the convention). -- You are receiving this because you commented. Reply to this email directly or view it on GitHub: https://github.com/cf-convention/cf-conventions/issues/148#issuecomment-436701377
