cam5 namelist variable dimensions

[aditya_nalam@caos_iisc_ernet_in]

Hi Forum,I am using E1850C5 compset and i want to prescribe some external forced sulfate aerosols.The namelist file in $CASEROOT/Buildconf/cam.inputdatalist says shows: ext_frc_specifier for so4_a1 = $DIN_LOC_ROOT/atm/cam/chem/trop_mozart_aero/emis/ar5_mam3_so4_a1_elev_1850_c090726.nc
ext_frc_specifier for so4_a2 = $DIN_LOC_ROOT/atm/cam/chem/trop_mozart_aero/emis/ar5_mam3_so4_a2_elev_1850_c090726.nc

the ncdump of the above mentioned file ncump -h ar5_mam3_so4_a2_elev_1850_c090726.nc hasdimensions:
    time = UNLIMITED ; // (12 currently)
    lat = 96 ;
    lon = 144 ;
    altitude = 13 ;
    altitude_int = 14 ;

and the ncdump of history file ncdump -h history.cam2.h0.0001-01.nc hasdimensions:
    lat = 96 ;
    lon = 144 ;
    slat = 95 ;
    slon = 144 ;
    time = UNLIMITED ; // (1 currently)
    nbnd = 2 ;
    chars = 8 ;
    lev = 30 ;
    ilev = 31 ;How can i deal with the dimension mismatch in vertical coordinate with the input data file and output data in order to analyse the evolution of external sulfate forcing? Please clarify.Also, the units for sulfate concentration is also different. The file ar5_mam3_so4_a2_elev_1850_c090726.nc hasfloat contvolc(time, altitude, lat, lon) ;
        contvolc:long_name = "aitken mode SO4 volcanic elevated emissions from aerocom contineous_volc.nc" ;
        contvolc:units = "molecules/cm3/s" ;and the file history.cam2.h0.0001-01.nc hasfloat so4_a1(time, lev, lat, lon) ;
        so4_a1:mdims = 1 ;
        so4_a1:units = "kg/kg" ;
        so4_a1:long_name = "so4_a1" ;
        so4_a1:cell_methods = "time: mean" ;
    float so4_a2(time, lev, lat, lon) ;
        so4_a2:mdims = 1 ;
        so4_a2:units = "kg/kg" ;
        so4_a2:long_name = "so4_a2" ;
        so4_a2:cell_methods = "time: mean" ;There is a mismatch in the units in both cases. How should i correct the units? Please help me out. Thanks a lotRegardsAdithya Nalam