A Novel Approach for Estimating Sea Surface Currents From Numerical Models and Satellite Images: Validation and Application

Ocean surface currents play a crucial role in understanding air-sea interactions, multiscale dynamics, and biogeochemical processes. Satellite remote sensing has become a powerful tool for global surface current mapping. In the past, the maximum cross correlation (MCC) method has been commonly used to estimate high-resolution surface currents over large areas. However, it has limitations in resolving finer, rotational, and deformational motions, producing erroneous and incoherent vectors. This study evaluates the reliability and robustness of a state-of-the-art window deformation iterative multigrid (WIDIM) approach in deriving high-resolution surface currents from realistic numerical model outputs. Comparisons with the “perfect” model currents show that the WIDIM method significantly outperforms the MCC method, especially in resolving strong rotational and deformation eddy velocity fields. The WIDIM method produces more accurate and coherent surface current estimates, with higher spatial resolution and fewer biases and errors. The application of the WIDIM method to satellite imagery also indicates that the WIDIM method provides remarkable improvement over the MCC method. Our findings highlight the potential of the WIDIM approach for advancing oceanographic research and practical applications.