convert daily to monthly
Added by mubashar dogar almost 12 years ago
I'm converting a daily file in monthly with cdo cdo monavg nswrs.sfc.gauss.1948.nc mon.nswrs.sfc.gauss.1948.nc Now when I opened the monthly file in GrADS it has correct 12 monthly values but wrong time convention. It is displaying time in GrADS as following
ga-> set t 1
Time values set: 1948:1:31:0 1948:1:31:0
ga-> set t 2
Time values set: 1948:3:2:0 1948:3:2:0
ga-> set t 3
Time values set: 1948:3:31:0 1948:3:31:0
ga-> set t 4
Time values set: 1948:5:1:0 1948:5:1:0
You could try cdo monthavg command on the attached daily file and then open it in GrADS to see the time problem. Please suggest me how can I handle this issue? I am using cdo/1.5.4 version
Thanks,
Mubashar
Replies (2)
RE: convert daily to monthly - Added by Jaison-Thomas Ambadan almost 12 years ago
Hi,
I'm not sure if this is a CDO problem. My guess is, it is due to the GrADS handling of the calender (366 days, leap year), may be due to different conventions?, I don't know. Anyway, you can "hard-code" the time-stamps and units with CDO after the averaging process:
cdo -settaxis,1948-01-01,00:00:00,1month -monavg nswrs.sfc.gauss.1948.nc monavg.nc
Now it will work in GrADS!
Cheers,
J.
RE: convert daily to monthly - Added by Uwe Schulzweida almost 12 years ago
As far as I know GrADS needs a constant time increment. A workaround is to set the day of month less than 29, e.g. 15:
cdo setday,15 -monavg nswrs.sfc.gauss.1948.nc result.nc
Regards,
Uwe