> There is currently a special meaning attached to reference dates of the form > `0-1-1`, for backward compatibility with COARDS, in section 7.4. Can we > remove this feature from `CF-1.9`?
That troublesome usage of `0-1-1` is already deprecated by the wording of 7.4 in all CF versions. [That section](https://cfconventions.org/Data/cf-conventions/cf-conventions-1.8/cf-conventions.html#climatological-statistics) also limits the special meaning to only the "real-world calendar". So if we can get consensus that dates earlier than year 1 are not valid in the existing `standard` and `julian` calendars under CF, I think it will be safe to leave the special meaning as deprecated, rather than removing it. [Section 7.4](https://cfconventions.org/Data/cf-conventions/cf-conventions-1.8/cf-conventions.html#climatological-statistics) also includes the only explicit treatment of the year zero concept in the entire document. `Year 0 may be a valid year in non-real-world calendars ...` This supports the possibility of explicit treatment of zero and negative years in alternate calendars. -- You are receiving this because you are subscribed to this thread. Reply to this email directly or view it on GitHub: https://github.com/cf-convention/cf-conventions/issues/298#issuecomment-703847821 This list forwards relevant notifications from Github. It is distinct from [email protected], although if you do nothing, a subscription to the UCAR list will result in a subscription to this list. To unsubscribe from this list only, send a message to [email protected].
