Ocean Circulation from Space

Abstract This paper reviews the recent progress in our estimation of ocean dynamic topography and derived surface geostrophic currents, mainly based on multiple nadir radar altimeter missions. These altimetric observations provide cornerstone circulation observing system from space. The largest signal sea is mean dominated by marine geoid, we will discuss altimetry, once geoid other corrections have been estimated removed. We then address advances large-scale mesoscale space, particular challenges opportunities for new polar regions. active research barotropic tides internal tidal also presented. addresses how networks global multi-satellite situ are being combined assimilated to characterize four-dimensional circulation, climate forecasting systems. For future need continuity current crucial, exciting enhancement come with wide-swath extension into coastal high-latitude regions, proposals direct total satellites 2030 period.