There are currently two versions of the EASE-Grid format, the original EASE-Grid and EASE-Grid 2.0:

Original EASE-Grid

• Defined in 1992
• Based on a spherical Earth model
• Used for many data sets

EASE-Grid 2.0

• Defined in 2011, recommended for new data sets
• Based on the WGS 84 ellipsoid
• Easier to use with today's software packages and formats like GeoTIFF
• Currently used for the Soil Moisture Active Passive (SMAP) project (publicly released data are forthcoming), and the MEaSUREs snow and ice project
• Planned to be used for the Passive Microwave ESDR MEaSUREs project