Hi Khairul,
Let's say your surface air temperature files are in $ARCHIVEDIR/khaab/03236
(I'm inventing khaab as your RUNID - it will be different for you).
You can create annual means using ppstats and the source daily mean output files (*a.pa*).
Remember PRECIS output uses the UM date stamp (see Appendix D of the PRECIS technical manual
http://www.precisrcm.com/PRECIS/tech_man.pdf )
Let's say your PRECIS run started in Dec 1969 and run until 2005, and you want annual mean files from 1971 to 2000.
1) Remove the spinup data
Code:
cd $ARCHIVEDIR/khaab/03236
mkdir SPINUP
mv khaaba.pag9* SPINUP/
mv khaaba.pah0* SPINUP/
(That removes g9 files [1969] and h0 [1970] from what you will analyse. Removing the spinup data is mandatory)
2) Remove the outer 8 point RIM
Code:
mkdir NORIM
pprr -r 8 -H "lbyr>1970 and lbyr<2001" -e NORIM khaaba.pa*
3) Calculate the annual means
Code:
cd NORIM
for udec in h ; do for uyr in 1 2 3 4 5 6 7 8 9 ; do ppstats -t mean -o khaaba.py${udec}${uyr}.ann.pp khaaba.pa${udec}${uyr}*.rr8.pp ; done ;done
for udec in i j ; do for uyr in 0 1 2 3 4 5 6 7 8 9 ; do ppstats -t mean -o khaaba.py${udec}${uyr}.ann.pp khaaba.pa${udec}${uyr}*.rr8.pp ; done ;done
for udec in k ; do for uyr in 0; do ppstats -t mean -o khaaba.py${udec}${uyr}.ann.pp khaaba.pa${udec}${uyr}*.rr8.pp ; done ;done
4) View a list of the annual means
ls *ann.pp
Each *ann.pp file is a mean of all files from the year.
Your annual means files in pp format then would need to be converted to netcdf format for CDO to operate on them.
David