Gravity

Physical Properties	Data Center	Selected Data Sets and Data Collections Complete data set listings available through each individual data center.
Gravity Gravity Field Models, Measurements	CDDIS http://cddis.gsfc.nasa.gov	Ground Network/Satellite Measurements: Daily, hourly, and sub-hourly code and phase observations from GNSS ground network; Daily and hourly files of round trip time of flight from satellite laser ranging (SLR) ground network; Time-tagged range-rate measurements from DORIS ground network Station positions and velocities from GNSS, SLR, VLBI and DORIS ground networks Daily and weekly precision satellite orbits derived from GNSS, SLR, and DORIS ground network observations. Note: Precise satellite orbits are required for higher level products.
Gravity Gravity Field Models, Measurements	PO DAAC http://podaac.jpl.nasa.gov	GRACE Level 2 Monthly Gravity Field Estimates Surface Mass Density Changes from GRACE (monthly mass grids of water equivalent thickness)

Cryosphere