Antarctic Time-Variable Regional Gravity Field Model Derived from Satellite Line-of-Sight Gravity Differences and Spherical Cap Harmonic Analysis ...

• Main Authors: Feizi, Mohsen, Raoofian Naeeni, Mehdi, Flury, Jakob
• Format: Article in Journal/Newspaper
• Language: English
• Published: Basel : MDPI 2023
• Subjects: LGD; SCHA; time-variable gravity model; GFO; L2 JPL; Dewey Decimal Classification600 | Technik620 | Ingenieurwissenschaften und Maschinenbau; Antarctic; Dewey; Laplace; Antarc*; Antarctica
• Online Access: https://dx.doi.org/10.15488/14718; https://www.repo.uni-hannover.de/handle/123456789/14836

This study focuses on the development of a time-variable regional geo-potential model for Antarctica using the spherical cap harmonic analysis (SCHA) basis functions. The model is derived from line-of-sight gravity difference (LGD) measurements obtained from the GRACE-Follow-On (GFO) mission. The solution of a Laplace equation for the boundary values over a spherical cap is used to expand the geo-potential coefficients in terms of Legendre functions with a real degree and integer order suitable for regional modelling, which is used to constrain the geo-potential coefficients using LGD measurements. To validate the performance of the SCHA, it is first utilized with LGD data derived from a L2 JPL (Level 2 product of the Jet Propulsion Laboratory). The obtained LGD data are used to compute the local geo-potential model up to Kmax = 20, corresponding to the SH degree and order up to 60. The comparison of the radial gravity on the Earth’s surface map across Antarctica with the corresponding radial gravity ...