The Xiamen Symposium on Marine Environmental Sciences (XMAS 2025)

Simultaneous direct measurements of ocean surface currents over a broad spatial area are technically unfeasible nowadays. Alternatively, successive high-resolution satellite images have become essential resources for retrieving ocean surface currents. This study aims to retrieve accuracy of ocean surface currents with high accuracy using a hybrid method (HM) that combines the window deformation iterative multigrid method (WIDIMM) with the optical flow method (OFM). Compared to the traditional maximum cross-correlation method, the WIDIMM has already demonstrated significant advantages in handling rotational and deformational flow fields. However, it ends up obtaining coarser-resolution flow fields compared to the resolution of used satellite images. By integrating the WIDIMM with OFM, we find that compared to the retrieval results based on WIDIMM, the HM not only improves the spatial resolution of the retrieved flow field but also significantly enhances its accuracy, as evidenced by both idealized experiments and realistic applications. In addition, the HM exhibits higher kinetic energy levels since it can resolve smaller-scale processes. This study demonstrates the potential of applying HM to obtain ocean surface currents with high resolution and accuracy, which might play an essential role in the study of oceanic submesoscale processes.