Chuanyin Wang (Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), China)

The recently launched Surface Water and Ocean Topography (SWOT) satellite provides an unprecedented two-dimensional measurement of the sea surface height down to the oceanic submesoscale of 1–10 km. Using this measurement to make substantial progress requires the separation of vortical and wavy motions owing to their contrasting ramifications for the energy transfer; however, the separation is extremely challenging due to the long-repeat period of the SWOT satellite. Here we propose a dynamics-based separation inspired by the initialization technique in numerical weather prediction. This separation utilizes the fundamental property that wavy motions induce no potential vorticity anomaly, and requires velocity data in addition to sea surface height. With concurrent measurements of sea surface height and velocity respectively from SWOT and the offshore high-frequency radar system, the proposed separation proves valid and useful. This study is expected to stimulate new discoveries associated with oceanic multiscale interactions and energy transfers.