Jay, Karl, fwiw:
If you need to get the actual date correct, at least throughout the
post-gregorian period (i.e., after 1582-10-15), then you should set
calendar to "proleptic_gregorian", and be careful to set your basetime
after 1582-10-15, I think. I don't think you can count on dates being
correct for times earlier than 1582-10-15, but maybe some software
does this right.
The ESMF proleptic Gregorian calendar goes back to 4801 BC. From Earl
Schwab,
the developer:
"[only going back to 4801 BC] is a limitation of the Fliegel/Van
Flandern algorithm, mentioned
in the ref doc for ESMF_TimeSet():
http://www.earthsystemmodeling.org/esmf_releases/last_built/ESMF_refdoc/node6.html#SECTION060541500000000000000
http://www.earthsystemmodeling.org/esmf_releases/last_built/ESMF_refdoc/node8.html#Fli68
Also, in the comments of the source in
ESMCI_Calendar.C:Calendar::convertToTime():
// The Fliegel algorithm implements the Gregorian calendar as
continuously
// proleptic from October 15, 1582 backward to March 1, -4800/-4900.
// Hence the algorithm does not take into account the Gregorian
Reformation
// (when the Gregorian calendar officially began) where 10 days were
// eliminated from the calendar in October 1582. Thursday, October
4, 1582
// was officially the last day of the Julian calendar; the following
day,
// Friday, was decreed to be October 15, 1582, the first day of the
// Gregorian calendar.
These limits are tested in our nightly runs via ESMF_CalRangeUTest.F90()."
Not sure if there is another algorithm that can go back before 4801 for
paleo people.
Cecelia
// The Fliegel algorithm implements the Gregorian calendar as
continuously
// proleptic from October 15, 1582 backward to March 1, -4800/-4900.
// Hence the algorithm does not take into account the Gregorian
Reformation
// (when the Gregorian calendar officially began) where 10 days were
// eliminated from the calendar in October 1582. Thursday, October
4, 1582
// was officially the last day of the Julian calendar; the following
day,
// Friday, was decreed to be October 15, 1582, the first day of the
// Gregorian calendar.
regards,
Karl
On 3/10/11 3:55 PM, Karl Taylor wrote:
Could someone please advise Jay?
thanks,
Karl
-------- Original Message --------
Subject: PALEO..
Date: Thu, 10 Mar 2011 11:37:51 -0800
From: Jay Hnilo <[email protected]>
To: Taylor, Karl Taylor <[email protected]>
Hi Karl,
If you happen to have some paleo data--how do you put it into
netcdf--knowing it goes from 10000 years ago to present day?
I'm asking mainly about the time.units, time.calendar, time coordinate values..
Thanks,
Jay
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===================================================================
Cecelia DeLuca
NESII/CIRES/NOAA Earth System Research Laboratory
325 Broadway, Boulder 80305-337
Email: [email protected]
Phone: 303-497-3604
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