TY - JOUR T1 - Global Observations of Fine-Scale Ocean Surface Topography With the Surface Water and Ocean Topography (SWOT) Mission A1 - Morrow,Rosemary A1 - Fu,Lee-Lueng A1 - Ardhuin,Fabrice A1 - Benkiran,Mounir A1 - Chapron,Bertrand A1 - Cosme,Emmanuel A1 - D’ovidio,Francesco A1 - Farrar,J. Thomas A1 - Gille,Sarah T. A1 - Lapeyre,Guillaume A1 - Le Traon,Pierre-Yves A1 - Pascual,Ananda A1 - Ponte,Aurelien A1 - Qiu,Bo A1 - Rascle,Nicolas A1 - Ubelmann,Clement A1 - Wang,Jinbo A1 - Zaron,Edward D. AD - Centre de Topographie des Océans et de l’Hydrosphère, Laboratoire d’Etudes en Géophysique et Océanographie Spatiale, CNRS, CNES, IRD, Université Toulouse III, Toulouse, France AD - Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA, United States AD - Laboratoire d’Océanographie Physique et Spatiale, Centre National de la Recherche Scientifique – Ifremer, Plouzané, France AD - Mercator Ocean, Ramonville-Saint-Agne, France AD - Institut des Géosciences de l’Environnement, Université Grenoble Alpes, Grenoble, France AD - Sorbonne Université, CNRS, IRD, MNHN, Laboratoire d’Océanographie et du Climat: Expérimentations et Approches Numériques (LOCEAN-IPSL), Paris, France AD - Woods Hole Oceanographic Institution, Woods Hole, MA, United States AD - Scripps Institution of Oceanography, University of California, San Diego, La Jolla, CA, United States AD - Laboratoire de Météorologie Dynamique (LMD-IPSL), CNRS, Ecole Normale Supérieure, Paris, France AD - IMEDEA (CSIC-UIB), Instituto Mediterráneo de Estudios Avanzados, Esporles, Spain AD - Department of Oceanography, University of Hawaii, Honolulu, HI, United States AD - Centro de Investigación Científica y de Educación Superior de Ensenada, Ensenada, Mexico AD - CLS Space Oceanography, Collecte Localisation Satellites, Toulouse, France AD - Department of Civil and Environmental Engineering, Portland State University, Portland, OR, United States AD - UR - https://archimer.ifremer.fr/doc/00495/60685/ DO - 10.3389/fmars.2019.00232 KW - ocean mesoscale circulation KW - satellite altimetry KW - SAR-interferometry KW - tides and internal tides KW - calibration-validation N2 - The future international Surface Water and Ocean Topography (SWOT) Mission, planned for launch in 2021, will make high-resolution 2D observations of sea-surface height using SAR radar interferometric techniques. SWOT will map the global and coastal oceans up to 77.6∘ latitude every 21 days over a swath of 120 km (20 km nadir gap). Today’s 2D mapped altimeter data can resolve ocean scales of 150 km wavelength whereas the SWOT measurement will extend our 2D observations down to 15–30 km, depending on sea state. SWOT will offer new opportunities to observe the oceanic dynamic processes at scales that are important in the generation and dissipation of kinetic energy in the ocean, and that facilitate the exchange of energy between the ocean interior and the upper layer. The active vertical exchanges linked to these scales have impacts on the local and global budgets of heat and carbon, and on nutrients for biogeochemical cycles. This review paper highlights the issues being addressed by the SWOT science community to understand SWOT’s very precise sea surface height (SSH)/surface pressure observations, and it explores how SWOT data will be combined with other satellite and in situ data and models to better understand the upper ocean 4D circulation (x, y, z, t) over the next decade. SWOT will provide unprecedented 2D ocean SSH observations down to 15–30 km in wavelength, which encompasses the scales of “balanced” geostrophic eddy motions, high-frequency internal tides and internal waves. This presents both a challenge in reconstructing the 4D upper ocean circulation, or in the assimilation of SSH in models, but also an opportunity to have global observations of the 2D structure of these phenomena, and to learn more about their interactions. At these small scales, ocean dynamics evolve rapidly, and combining SWOT 2D SSH data with other satellite or in situ data with different space-time coverage is also a challenge. SWOT’s new technology will be a forerunner for the future altimetric observing system, and so advancing on these issues today will pave the way for our future. Y1 - 2019/05 PB - Frontiers Media SA JF - Frontiers In Marine Science SN - 2296-7745 VL - 6 IS - 232 ID - 60685 ER -