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z_cams_c_ ecmf_20160704000000_prod_fc_pl_012_co.grib contains all the pressure levels of +12 step CO fields from a forecast started on 7 July 2016 at 00:00 UTC.
z_cams_c_ ecmf ecmf_20160704120000_prod_fc_ml_012_go3.nc nc contains all the model levels of step 12 O3 fields from a forecast which was started on 7 July 2016 at 12:00 UTC in NetCDF format.
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