A modified method for recovering bathymetry from altimeter data

At present, there exist two types of methods to recover the bathymetry from altimeter data, i.e. the deterministic method and the stochastic one. This paper first reviews the general principles of the two aforementioned methods in order to form the basis for the development of the new approach. Then, based on the theory of least-squares collocation, a modified statistical model for recovering bathymetry from altimeter data is proposed. The new model is used to compute the ocean depth in the South China Sea from altimetry-derived gravity anomalies. Finally the predicted depths are compared to the shipborne ones. The results show that the achievable agreement is very good. Taking into account the existence of errors in the shipborne depths, it can be believed that the relative error of altimetry-derived depths reaches the level of about 7%.