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What is the difference between the global (90°N-S) and full (60°N-S) coverage for IMERG?

Compared to previous versions, Version 06 IMERG introduces additional coverage at the high latitudes for the precipitation fields in all Runs -- Early, Late, and Final.  IMERG continues to use a merged geosynchronous infrared brightness temperature analysis to provide IR-based precipitation estimates.  The requisite analysis (provided by NOAA/NWS/Climate Prediction Center) covers the latitude band 60°N-S, so a "full" IMERG analysis is possible there.  At higher latitudes (in both hemispheres) IR-based estimates cannot be included, so the coverage in the complete precipitation fields is "partial" -- limited to gridboxes for which there is no snow/ice on the surface.  Some of the other data fields, specifically the merged microwave estimates and the precipitation phase, are provided for the entire globe.