Level 1( Grided products from SMAP level 1 converters at the NSIDC DAAC. HEG Stand-alone does not process Level 1 data downloaded without conversion from NSIDC.)
Level 2( Grided products from SMAP level 2 converters at the NSIDC DAAC. HEG Stand-alone does not process Level 2 data downloaded without conversion from NSIDC.)
Level 3
Level 4