Hi Martin and all:
Im wondering what essential methods a calendar library needs to have to
support, eg 360 day calendars? The only one that comes to mind is to
calculate the difference between two dates in, say, seconds? What else?
John
On 4/1/2011 12:55 AM, Schultz, Martin wrote:
Hi Chris et al.,
indeed it seems like some clarification is necessary about the use of different
calendars in modelling. Your suggestion to "map" the 360 day calendar onto the
Gregorian calendar in output files won't work: there would be no need for a 360 day
calendar if it would. The idea behind fixed-length-year calendars is precisely the
opposite: preserve seasonality without having to deal with leap years etc. Of course you
need to adjust the solar cycle accordingly, that means your model will have a solar year
that is precisely 360 days long (and not 365.25 as in reality). If you were to map these
dates onto the gregorian calendar, you would have to interpolate the time axis so that
days 1 to 360 fit into the range 1 to 365 or 366, respectively. Yes - a converter
360-days (or 365-days) to gregorian (and reverse) could be written, but you would redce
the number of your friends if you insist that this is the only valid way to represent
time of the model output ;-)
You are right that a date such as 1960-01-31 is invalid in a 360-day
calendar, and indeed a smart tool should flag this as an error.
Hope this helps,
Martin
------------------------------------------------------------------------------------------------
------------------------------------------------------------------------------------------------
Forschungszentrum Juelich GmbH
52425 Juelich
Sitz der Gesellschaft: Juelich
Eingetragen im Handelsregister des Amtsgerichts Dueren Nr. HR B 3498
Vorsitzender des Aufsichtsrats: MinDirig Dr. Karl Eugen Huthmacher
Geschaeftsfuehrung: Prof. Dr. Achim Bachem (Vorsitzender),
Dr. Ulrich Krafft (stellv. Vorsitzender), Prof. Dr.-Ing. Harald Bolt,
Prof. Dr. Sebastian M. Schmidt
------------------------------------------------------------------------------------------------
------------------------------------------------------------------------------------------------
Besuchen Sie uns auf unserem neuen Webauftritt unter www.fz-juelich.de
_______________________________________________
CF-metadata mailing list
[email protected]
http://mailman.cgd.ucar.edu/mailman/listinfo/cf-metadata
_______________________________________________
CF-metadata mailing list
[email protected]
http://mailman.cgd.ucar.edu/mailman/listinfo/cf-metadata
