Exploiting the Combined GRACE/GRACE-FO Solutions to Determine Gravimetric Excitations of Polar Motion

Observations from the Gravity Recovery and Climate Experiment (GRACE) GRACE Follow-On (GRACE-FO) missions can be used to estimate gravimetric excitation of polar motion (PM), which reflects contribution mass changes in continental hydrosphere cryosphere PM variation. Many solutions for Earth’s gravity field variations have been developed by institutes around world based on GRACE/GRACE-FO data; however, it remains inconclusive them is most reliable determination excitation. In this study, we present a combined series GRACE/GRACE-FO-based computed using three-cornered-hat (TCH) method, wherein internal noise level solution reduced minimum. We compare with results obtained provided COST-G (International Combination Service Time-variable Fields) single elaborated Center Space Research (CSR). All are evaluated comparison sum hydrological cryospheric signals geodetically observed (called GAO). The show that minimizing TCH receive higher consistency GAO than case CSR solutions, especially non-seasonal oscillations. For spectral band, correlations between best-combined as high 0.65 0.72 ?1 ?2 equatorial components excitation, respectively. corresponding values seasonal oscillation were 0.91 0.89 ?2. study explain up 68% 60% overall variability ?2,