The MERRA is a NASA reanalysis for the satellite era using a major new version (V5) of the Goddard Earth Observing System (GEOS) Data Assimilation System (DAS). The MERRA focuses on historical analyses of the hydrological cycle on a broad range of weather and climate time scales.
This MERRA Instance of Giovanni focuses on visualizing and analyzing the MERRA monthly data from the MERRA CHEMISTRY FORCING COLLECTIONS.