8c961685-cecb-41d9-b2d9-2a22cdd3d0c2

The SWOT L3_LR_SSH product provides ocean topography measurements obtained from the SWOT KaRIn and nadir altimeter instruments, merged into a single variable. The dataset includes measurements from KaRIn swaths on both sides of the image, while the measurements from the nadir altimeter are located in the central columns. In the areas between the nadir track and the two KaRIn swaths, as well as on the outer edges of each swath (restricted to cross-track distances ranging from 10 to 60 km), default values are expected. SWOT L3_LR_SSH is a cross-calibrated product from multiple missions that contains only the ocean topography content necessary for thematic research (e.g., oceanography, geodesy) and related applications. This product is designed to be simple and ready-to-use, and can be combined with other altimetry missions. The SWOT L3_LR_SSH product is a research-orientated extension of the L2_LR_SSH product, distributed by the SWOT project (NASA/JPL and CNES). SWOT L3_LR_SSH is managed by the SWOT Science Team project DESMOS. The "Expert" version of SWOT L3_LR_SSH (the "Basic" version is the subject of a separate metadata sheet) includes each algorithm, correction, or external model incorporated into the SWOT L3_LR_SSH product as a separate layer. In addition to the SSH anomalies, this "Expert" version also includes mean dynamic topography (as in the "Basic" version), backscatter coefficient (sigma0), mean sea surface and geostrophic currents (absolute and anomalies). References Dibarboure, G., Anadon, C., Briol, F., Cadier, E., Chevrier, R., Delepoulle, A., Faugère, Y., Laloue, A., Morrow, R., Picot, N., Prandi, P., Pujol, M.-I., Raynal, M., Tréboutte, A., and Ubelmann, C.: Blending 2D topography images from the Surface Water and Ocean Topography (SWOT) mission into the altimeter constellation with the Level-3 multi-mission Data Unification and Altimeter Combination System (DUACS), Ocean Sci., 21, 283–323, https://doi.org/10.5194/os-21-283-2025.