[ferret_users] two days shift

[Sang-ki Lee <Sang-ki.Lee@xxxxxxxx>]

I have a netcdf file for global monthly SST from
"01-JAN-1870 12:00:00" to "01-JAN-2006 12:00:00".

Here is the header info of the netcdf file:
----------------------------------------------------------------------
time:long_name = "Time" ;
time:units = "hours since 1-1-1 00:00:0.0" ;
time:delta_t = "0000-00-01 00:00:00" ;

time = 16383372, 16384116, 16384788 ......, 17584284
----------------------------------------------------------------------

Now, I have the same dataset but separate netcdf files for individual
month. I created a descriptor file to be able to read all files at
once. And I used the same time header info in the descriptor file:

D_TITLE       = 'HADISST',
D_T0TIME      = '1-JAN-0001 00:00:00',
D_TIME_UNIT   =  3600.,
D_CALTYPE     =  GREGORIAN,
D_TIME_MODULO = .FALSE.,

But, when I read the descriptor file, the time index is shifted
exactly two days forward. For instance the first month is read
as "03-JAN-1870 12:00:00" instead of "01-JAN-1870 12:00:00".

Of course, I can simply change D_T0TIME to '30-DEC-0000 00:00:00'
for a quick fix. But, I am wondering why this is happening.
And, I also want to make sure that changing D_T0TIME to
'30-DEC-0000 00:00:00' is the right way to fix this problem.

Thank you.

Sang-ki
--
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Dr. Sang-ki Lee
RSMAS/CIMAS
University of Miami
4600 Rickenbacker Causeway
Miami, FL 33149 USA
Tel) 305-361-4521
Fax) 305-361-4412
E-mail) sang-ki.lee@xxxxxxxx
Homepage) http://www.aoml.noaa.gov/phod/people/sklee.html
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Mailing-address:
Dr. Sang-ki Lee
AOML/PHOD
4301 Rickenbacker Causeway
Miami, FL, 33149 USA
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