The Integrated Forecast System (IFS) of the ECMWF uses a ozone climatology for radiative
transfer instead of the ozone simulated by the IFS. If this option is activated the ozone profile of the
atmosphere_file or ECMWF_atmosphere_file is replaced by the ozone climatology.
(If there is also a dens_file for ozone, it modifies the ozone climatology profile.)
Arve Kylling
2010-03-10