Dear Russ,
Many thanks one again. It worked.
As mentioned in your script the following two lines, I think they are not needed (if i am wrong let me know):
let mask = if EMISS_AWB_BC[d=india_T63] then 1
let EMISS_AWB_BC_COMMON = if mask then EMISS_AWB_BC[d=india_T63]
else EMISS_AWB_BC[global_T63]
Please find below my script (let me know if I am doing any mistake in below script):
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cancel data/all
use global_T63.nc
use india_T63.nc
let EMISS_AWB_BC_COMMON = if EMISS_AWB_BC[d=2,l=1:12] then EMISS_AWB_BC[d=2,l=1:12] else EMISS_AWB_BC[d=1,l=1:12]
save/file=
common.nc EMISS_AWB_BC_COMMON[l=1:12]
quit
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