Local Oceanic Vertical Deflection Determination with Gravity Data Along a Profile

ABSTRACT

Deflections of the vertical (DOVs) over oceans cannot be directly measured, which restricts their applications. A local covariance function of anomalous potential is put forward in this paper in conjunction with the least-squares collocation (LSC) method to compute the oceanic DOVs utilization of oceanic gravity data along a profile. The covariance functions of gravity field quantities have been derived directly as functions of x, y and z without the need to introduce coordinate transformations corresponding to along- or cross-profile components. In the proposed methodology, gravity data along a profile were used to calculate the residual gravity anomaly using the remove-compute-restore technique. The residual gravity anomaly was used to calculate the parameters of the proposed covariance function of the local anomalous gravity field, which was used in the LSC to compute the residual DOVs along the profile. The residual DOVs added model DOVs to recover the DOVs along the profile. The results of a simulation experiment prove that the proposed methodology is feasible and effective.

KEYWORDS:

• Deflections of the vertical
• gravity data
• local covariance function of anomalous potential
• least-squares collocation

Acknowledgements

We thank the editor and anonymous reviewers for their helpful comments.

Additional information

Funding

This study is supported by the National Natural Science Foundation of China (Grant No. 41374009 and 41774001), the Shandong Natural Science Foundation of China (Grant No. ZR2013DM009), the Basic Science and Technology Project of China (Grant No. 2015FY310200), and the SDUST Research Fund (Grant No. 2014TDJH101).