The files included in MITgcm_inputs.tar.gz were/are necessary to run the MITgcm_ocean model from within the DART framework. They are too big to include with the DART code tree, so they are provided here with no guarantee that they will work with your instance of the MITgcm ocean model, etc.
[thoar@mirage2 ~]$ tar -tzvf MITgcm_inputs.tar.gz -rw-r--r-- thoar/ncar 230400 2008-05-21 10:30:32 inputs/bathymetry.bin -rw-r--r-- thoar/ncar 3175 2008-07-28 16:50:11 inputs/data -rw-r--r-- thoar/ncar 150 2008-06-17 17:38:39 inputs/data.cal -rw-r--r-- thoar/ncar 15167 2008-05-21 13:18:58 inputs/data.exf -rw-r--r-- thoar/ncar 133 2008-05-21 12:17:43 inputs/data.kpp -rw-r--r-- thoar/ncar 733 2008-05-21 12:16:19 inputs/data.obcs -rw-r--r-- thoar/ncar 137 2008-05-21 12:16:37 inputs/data.pkg -rw-r--r-- thoar/ncar 303 2008-05-21 10:29:27 inputs/eedata -rw-r--r-- thoar/ncar 230400 2008-05-21 12:22:33 inputs/gom_H_199601.bin -rw-r--r-- thoar/ncar 9216000 2008-05-21 12:22:09 inputs/gom_S_199601.bin -rw-r--r-- thoar/ncar 9216000 2008-05-21 12:22:17 inputs/gom_T_199601.bin -rw-r--r-- thoar/ncar 9216000 2008-05-21 12:22:23 inputs/gom_U_199601.bin -rw-r--r-- thoar/ncar 9216000 2008-05-21 12:22:28 inputs/gom_V_199601.bin -rw-r--r-- thoar/ncar 2764800 2008-05-21 12:26:29 inputs/lev05_monthly_sss_relax.bin -rw-r--r-- thoar/ncar 2764800 2008-05-21 12:26:18 inputs/lev05_monthly_sst_relax.bin -rw-r--r-- thoar/ncar 2237952 2008-05-21 12:26:57 inputs/ncep_air_19960101.bin -rw-r--r-- thoar/ncar 2237952 2008-05-21 12:27:51 inputs/ncep_dlwrf_19960101.bin -rw-r--r-- thoar/ncar 2237952 2008-05-21 12:27:21 inputs/ncep_dswrf_19960101.bin -rw-r--r-- thoar/ncar 2237952 2008-05-21 12:27:32 inputs/ncep_nswrs_19960101.bin -rw-r--r-- thoar/ncar 2237952 2008-05-21 12:26:47 inputs/ncep_prate_19960101.bin -rw-r--r-- thoar/ncar 2237952 2008-05-21 12:27:11 inputs/ncep_shum_19960101.bin -rw-r--r-- thoar/ncar 2237952 2008-05-21 12:28:05 inputs/ncep_uwnd_19960101.bin -rw-r--r-- thoar/ncar 2237952 2008-05-21 12:28:13 inputs/ncep_vwnd_19960101.bin -rw-r--r-- thoar/ncar 21600000 2008-05-21 12:49:38 inputs/Rs_SobcsE_52_01_nPx1.bin -rw-r--r-- thoar/ncar 24576000 2008-05-21 12:50:29 inputs/Rs_SobcsN_52_01_nPy1.bin -rw-r--r-- thoar/ncar 21600000 2008-05-21 12:49:23 inputs/Rs_TobcsE_52_01_nPx1.bin -rw-r--r-- thoar/ncar 24576000 2008-05-21 12:50:17 inputs/Rs_TobcsN_52_01_nPy1.bin -rw-r--r-- thoar/ncar 21600000 2008-05-21 12:48:54 inputs/Rs_UobcsE_52_01_nPx1_c1.bin -rw-r--r-- thoar/ncar 24576000 2008-05-21 12:49:53 inputs/Rs_UobcsN_52_01_nPy1.bin -rw-r--r-- thoar/ncar 21600000 2008-05-21 12:49:10 inputs/Rs_VobcsE_52_01_nPx1.bin -rw-r--r-- thoar/ncar 24576000 2008-05-21 12:50:05 inputs/Rs_VobcsN_52_01_nPy1_c1.bin -rw-r--r-- thoar/ncar 2764800 2008-05-21 12:28:26 inputs/run-off.bin_1x1
All I know is that I needed them to test both the free run and the assimilation experiments.
For more information, see the README in the MITgcm_ocean/inputs directory of DART.