海洋科学学术讲座预告第493期：Roles of Tidesand MesoscaleEddies/Wavesin AntarcticBottomWater Formation

Antarctic Bottom Water (AABW) formation involves complex processes, from dense shelf water (DSW) production in coastal polynyas to its downslope transport into the deep ocean. The intrinsic instability of DSW export and tidal effects may play key roles, yet these processes remain poorly understood due to limited observations. Using new-generation SWOT satellite altimetry, in-situ observations, and numerical models, we examine the roles of tides and mesoscale eddies/waves in AABW formation. Our main results show that DSW export over the continental shelf generates abundant mesoscale eddies, which are clearly detectable by SWOT. The instability of DSW over the continental slope excites topographic Rossby waves (TRWs), which act to accelerate DSW downslope transport. Tides can suppress DSW mixing over steep continental slopes, favoring the formation of colder and denser AABW. We further classify the dynamical regimes of dense overflows around Antarctica based on the relative importance of TRWs and tides.