Progress of temporal gravity field model determination in terms of spherical harmonic coefficients via satellite-to-satellite tracking observations

Abstract

Temporal gravity field comprehensively reflects the migration characteristics of the earth's inner and shallow mass variations, which has been widely used in various geoscience applications. Since the 21st century, several gravimetric satellites have been successfully launched, supporting to continuously detecting global temporal gravity field. The way to determine temporal gravity field model in terms of spherical harmonic coefficients via satellite gravimetric data is the key issue, and it is the prerequisite to further promote numerous geoscience applications. Since the proposal of satellite gravimetry, scholars at home and abroad have been dedicated to studying the theories and methods of retrieving temporal gravity field model for several decades. Due to the refinement of observations and the improvement of retrieval methods, there are significant improvements of the accuracy of temporal gravity field models. This paper summarizes the research progress of determining temporal gravity field models via satellite tracking satellite data in recent decades. In terms of low-low satellite-to-satellite tracking scenario, we summarize the basic principle of retrieval method, the optimization process of observation datasets, the refinement of background force models and the improvement of retrieval methods. Meanwhile, the progress in terms of high-low satellite-to-satellite tracking scenarios is also presented, especially for temporal gravity field models determination. Finally, the future opportunities of the next generation gravimetric mission are discussed. Our findings could benefit the construction and development of autonomous gravity satellites in China.

Keywords

• temporal gravity field model
• satellite gravimetry
• satellite-to-satellite tracking
• next generation gravimetric mission.