depvel_defs(6,5,jpdd)
see ASAD_MOD
6 = Number of time periods used in dry deposition i.e. summer(day,night,24h ave), winter(day,night,24h ave) - 24h aves not used
5 = Number of land use categories used in dry dep. (water,forest,grass,desert,ice) - desert not used
see ukca_ddeprt.F90 for allocation
