Abstract:

Since the lunch of the GRACE (Gravity Recovery and Climate Experiment) satellite in March 2002, gravity model and data quality have been improved significantly. GRACE can provide a large mount of highly accurate and continuous GPS and K-Band Ranging (KBR) data in just one day in low orbits. Therefore, some low degree harmonic coefficients of the Earth’s gravity field can be very well determined using just one-day GRACE data. Those results can be used to detect high frequency variations in the Earth’s gravity field. Because most the high frequency variations are from atmospheric and oceanic mass redistribution, they can be used to validate and/or assess atmospheric and oceanic dealiasing models. Comparison between the GRACE daily gravity solutions and the predictions from different atmosphere and ocean geophysical models show a remarkably good agreement. In addition, the daily solutions using different atmosphere and ocean models are also compared and analyzed.