Gravity acceleration at the sea surface derived from satellite altimetry data using harmonic splines


Gravity acceleration data have grand pursuit for marine applications. Due to environmental effects, marine gravity observations always hold a high noise level. In this paper, we propose an approach to produce marine gravity data using satellite altimetry, high-resolution geopotential models and harmonic splines. On the one hand, harmonic spline functions have great capability for local gravity field modeling. On the other hand, the information from satellite altimetry is a viable source of information for the marine gravimetry in the high-frequency gravity field modeling. Marine geoid from satellite altimetry observations can be converted to disturbing potential via ellipsoidal Bruns’s formula. The reference gravity field’s contribution is removed and restored after solving Dirichlet Boundary Value Problem. Finally, the results are downward continued to the sea surface using free air scheme. Computation of gravity acceleration in the Persian Gulf and its compatibility with the shipborne data shows reasonable performance of this methodology.