Reprocessing of the CryoSat-2; do solar cycles affect the quality of orbits?
Ernst Schrama (TU Delft, Netherlands)
Event: 2026 IDS Workshop
Session: Advances in Satellite Dynamics and Orbit Determination
Presentation type: Oral
DOI: 10.24400/312072/i03-2026.4506
Licence: 
Abstract
We reprocessed CryoSat-2 tracking data up to March 2026 using laser and DORIS observations. The dynamical modeling of the satellite includes gravity, tide models, solar radiation pressure, and thermospheric drag. We fix beacon and laser station coordinates in a chosen reference system, while estimating pass-specific biases to account for beacon frequency variations and tropospheric delay. Time-variable gravity effects are corrected using the AOD1B model, and empirical accelerations are applied to further refine the orbit dynamics. The goal is to independently assess the quality of the CryoSat-2 orbit solutions. On average we achieve radial misclosures better than 10 mm relative to the precision orbit product used on the geophysical data records, Doppler residuals below 0.45 mm/s, and laser residuals of about 10 mm. Over the 16 years since launch, this analysis reveals how orbit quality evolves over time. The study period spans the transition from solar cycle 24 to 25, reflected in changes in solar activity indicators such as F10.7. A key question we address is whether increased solar activity—and the resulting changes in the thermospheric environment—has a measurable impact on orbit quality.
Contribution: IDS26_s3_Schrama-ReprocessingCryosat2.pdf (pdf, 1820 ko)
Corresponding author:
Ernst Schrama
TU Delft
Netherlands
