CDO

Hi Abubakar,

you have to take care computing seasons because per default CDO uses DJF, MAM, JJA, SON seasons. For DJF not problem, but you have to change the start month of the season to JAN for JFM and OND. Here is a script. If you have problems furthermore it is more a grads question.

#!/usr/bin/env ksh

export CDO_TIMESTAT_DATE=middle

export CDO_SEASON_START=JAN   # <-- change season start month

infile="$HOME/data/CMIP5/atmos/va_Amon_MPI-ESM-LR_historical_r1i1p1_198001-198912.nc" 

cdo -selseas,JFM -sellevel,100000 $infile JFM.nc
cdo -seasmean JFM.nc Mean_JFM.nc
cdo -timmean Mean_JFM.nc L.mean.JFM.nc
cdo -sub Mean_JFM.nc L.mean.JFM.nc Ano.JFM.nc
cdo -selyear,1989 Ano.JFM.nc ano.JFM89.nc
#-----------------------------------------------------------
cdo -selseas,OND -sellevel,100000 $infile OND.nc
cdo -seasmean OND.nc Mean_OND.nc
cdo -timmean Mean_OND.nc L.mean.OND.nc
cdo -sub Mean_OND.nc L.mean.OND.nc Ano.OND.nc
cdo -selyear,1989 Ano.OND.nc ano.OND89.nc
#-----------------------------------------------------------
export CDO_SEASON_START=DEC    # <-- change back

cdo -selseas,DJF -sellevel,100000 $infile DJF.nc
cdo -selmonth,1 -seasmean -seltimestep,3/29 DJF.nc Mean_DJF.nc
cdo -timmean Mean_DJF.nc L.mean.DJF.nc
cdo -sub Mean_DJF.nc L.mean.DJF.nc Ano.DJF.nc
cdo -selyear,1989 Ano.DJF.nc ano.DJF89.nc

-Karin

Hi karim
Thank you for the support, it works perfectly for the seasons JFM and OND but my DJF is not for the same year.