Assessment of the Performance of SWOT for Observing the Static Ocean Topography

Marine geodetic references, such as the mean sea surface (MSS), are currently limited by the spatial resolution of conventional satellite altimeters. We analyze the new swath-altimetry data from the Surface Water and Ocean Topography (SWOT) satellite, to determine the performance of SWOT for mapping the static ocean topography, and possible benefit of inclusion in future reference models. By determining how well SWOT observes the static features in the ocean surface during SWOTs fast-sampling phase, we have determined the expected performance during the science phase of the mission. We observe a 50% reduction in variability of the static surface compared with Sentinel-3, whilst resolving up to 36% shorter wavelengths (down to $\sim$8 km) compared to the current state-of-the-art Hybrid23 MSS reference model. Comparisons with Sentinel-3 show that SWOT will benefit the current altimetry record.