Space weather signatures in accelerometer measurements of GRACE-FO C: Insights from 10 Hz measurements

Accelerometer measurements are essential for accurate gravity field recovery and for the extraction of thermospheric density used in drag estimation. The GRACE-C accelerometer is among the few instruments currently providing measurements of sufficient accuracy for these applications. With the advent of a new generation of gravity missions, it is increasingly important to characterise non-gravitational disturbances in order to identify additional phenomena that may affect accelerometer observations. This study analyses the 10 Hz accelerometer measurements from GRACE-C, which represent the highest-cadence dataset available to date. We investigate the characteristic signal signatures associated with terminator crossings, field-aligned currents, and geomagnetic storms under both low and high solar activity conditions. The aim is to improve the understanding of how space weather processes influence accelerometer measurements and, consequently, gravity field determination and thermospheric densities retrieval.