National Centers for Environmental Information / National Operational Model Archive and Distribution System Catalog https://www.ncei.noaa.gov/thredds/catalog/model/nnr2.html

Dataset Size Last Modified
     Folder  NCEP/DoE Reanalysis II   --
         Folder  NCEP/NCAR Reanalysis II (NNR2) 6-hour - File Units/   --
         Folder  NCEP/NCAR Reanalysis II (NNR2) montly - File Units/   --

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