The exchange of properties between the ocean and atmosphere, including heat, carbon, and oxygen, is affected by subduction, which is the transport of water from the surface mixed layer into the stratified pycnocline. Subduction ventilates the pycnocline, affects the water mass characteristics of the interior, and impacts the ocean's biogeochemistry. The seasonal transformation of the mixed layer and the large-scale circulation (Lévy et al., 2013;Nurser & Marshall, 1991) leads to subduction through diabatic processes. In addition, subduction occurs along sloping isopycnals at fronts, where mixed-layer enhanced submesoscale processes enhance vertical advection on horizontal scales of 0.1-10 km (