Avoidance of undefined-variable use in OBS
ORCA2_ICE_OBS SETTE test of both NEMO
branch_4.2 has failed when run in debug mode due to the use of an undefined variable.
.FALSE. in subroutine
obs_surf_opt of module
obs_oper, the undefined variable
idayend is accessed during the evaluation of the condition in two
IF constructs could be restructured into nested
IF constructs that test
ldnightav in the first instance.