One must create a BASH header file. For example, on CICLAD, the following works well:
# cdb_header.sh
# PROGRAMS:
#
export CDB_CDO_PATH="/home/$USER/local/cdo/bin"
export CDB_NCO_PATH="/home/$USER/local/nco/bin"
export CDB_PYTHON_PATH="/home/$USER/local/bin"
#
# DIRECTORIES:
#
export CDB_DIAG_DIR="/home/$USER/CDB/diags"
export CDB_SCRIPT_DIR="/home/$USER/CDB/scripts"
export CDB_SOURCE_DIR="/home/$USER/CDB/driver"
export CDB_IN_DIR="/home/$USER/CDB/in"
export CDB_OUT_DIR="/data/$USER/CDB/out"
export CDB_TEMP_DIR="/data/$USER/CDB/temp/$USER"
export CDB_DATA_DIR="/prodigfs/esg/CMIP5/merge"