The geodetic infrastructure provides the largely invisible foundation for all the great geodesy data we have today (e.g., GNSS, InSAR, lidar, . . .). Moreover, many of NASA’s Earth Science missions planned for this decade (e.g., ICESAT-2, GRACE-FO, SWOT, and NISAR) rely on the geodetic infrastructure for computing the precise orbits needed for their basic observations. Without the GI, these missions would be space junk. The GI consists of 4 global measurement systems (VLBI, SLR, GNSS, DORIS) used to define the International Terrestrial Reference Frame (ITRF).
This talk will focus on 5 science themes that rely on maintenance and enhancements to the geodetic infrastructure. The most stringent requirements for the accuracy and stability of the terrestrial reference frame are driven by science questions related to sea-level change, ice-mass loss, and land-surface deformation associated with the movement of water over the surface of the land, cryosphere, and oceans as well as the elastic and viscoelastic response of the solid Earth to water loading, earthquakes, and volcanic eruptions.