Simulation with double call to radiation for MACv2 aerosols,
in order to calculate IRF (with respect to preindustrial).

See COMP/lmdz.card :
  note the use of PARAM/*.xml_2RadCall files
       (key elements : groups "fields_irf_aer_standard" and "fields_irf_aer_CMIPstyle"; only the later is activated)
  and the post-processing (TS_MO) for aerosol IRF variables
       (with CMIPstyle irf* names instead of the native "tospswad, topswai…")