[ferret_users] append variables on time when time reference (since date) are different

[Brockmann Patrick <Patrick.Brockmann@xxxxxx>]

Hi all,

I have a problem when I work with 2 variables
that has a time axis with a different time reference.

ncdump file_1850_2005.nc
   TIME:units = "days since 1850-01-01 00:00:00" ;
   TIME:time_origin = "01-JAN-1850 00:00:00" ;

ncdump file_2006_2100.nc
   TIME:units = "days since 2006-01-01 00:00:00" ;
   TIME:time_origin = "01-JAN-2006 00:00:00" ;

The result is wrong and it seems that the 2 time series have been
overlapped. See attached image.

Note that when you use the cdo operator cat, the result is correct.
(time reference are first phased then variables are appended).
cdo cat file_1850_2005.nc file_2006_2100.nc file_cat.nc

I have also tried with the TCAT function, but then I loose the time
axis.
Is there a pure ferret solution to this append problem ?

Attached the 2 different files to append
and the err672_append_with_different_reference_date.jnl

Patrick

--
LSCE/IPSL, Laboratoire CEA-CNRS-UVSQ
Data Analysis and Visualization Engineer
ICMC - IPSL Climate Modelling Centre
--

cancel data/all
cancel var/all

!############################
use file_1850_2005.nc
show grid a

use file_2006_2100.nc
show grid a

set v upper
plot/hlim="01-JAN-1850":"31-DEC-2100" a[d=1],a[d=2]

!############################
save/clobber/file=file_cat.nc a[d=1],a[d=2]

use file_cat.nc

set v lower
plot/hlim="01-JAN-1850":"31-DEC-2100" a[d=3]

Attachment: file_1850_2005.nc
Description: Binary data

Attachment: file_2006_2100.nc
Description: Binary data