Chang, J.-X., and Arbic, B.K. (2026)
Presented at:
Ocean Sciences Meeting 2026The Surface Water and Ocean Topography (SWOT) satellite provides two-dimensional sea surface height (SSH) measurements at sub-10 km resolution. We use SWOT Level 3 1-day SSH data in the Kuroshio region to investigate surface kinetic energy transfers and the validity of balance assumptions at submesoscales. The SSH field is separated into wave and eddy components using a recent method. The eddy component is used to compute velocities under both geostrophic and cyclogeostrophic assumptions, allowing us to assess how balance choices affect inferred flows. From the filtered SSH, we compute relative vorticity and the Jacobian of streamfunction and vorticity, forming the basis for spectral flux diagnostics. Spectral energy transfers are quantified using both the Fourier-based method of Arbic et al. (2013, JPO) and the coarse-graining framework of Aluie et al. (2018, JPO). These complementary approaches allow us to identify the direction of kinetic energy cascades—both inverse and forward—based on SWOT observations. Results from SWOT will be compared with AVISO altimetry and MITgcm LLC simulations to evaluate the consistency of observed and modeled energy transfers.
