A General Method For Sea Surface Velocity Retrieval From SAR Doppler Centroid

Retrieving two-dimensional sea surface velocity field in the open ocean remains an unresolved challenge in satellite remote sensing. Our analysis demonstrates that the gradients of the sea surface velocity field exhibit a linear correlation with the gradient fields of the eastward and northward velocity components in two dimensions; however, this relationship is not strictly unimodal. Based on this linear correlation, we developed an integral approximation method to retrieve the two-dimensional sea surface velocity field from the gradient of the sea surface speed field which is retrieved from satellite data. The effectiveness of this method was thoroughly validated. Additionally, we devised a technique to decompose the sea surface current field into distinct components, including the geostrophic and Ekman currents, offering a robust framework for independent analysis of different current components across various spatial and temporal scales.