Abstract
Mixed-layer depth (MLD) exhibits significant variability, which is important for atmosphere-ocean exchanges of heat and atmospheric gases. Origins of the MLD variability at the oceanic mesoscale in the Southern Ocean are studied here in an idealized Regional Ocean-Atmosphere Model (ROAM). The main conclusion from the analysis of the upper-ocean buoyancy budget is that, while the atmospheric forcing and oceanic vertical mixing induce the MLD variability on average, the oceanic advection of buoyancy counteracts and partially balances these atmospheric effects. The relative importance of advection changes with season and large-scale MLD. This study emphasizes the importance of oceanic advection and intrinsic ocean dynamics in driving mesoscale MLD variability, and demonstrates the importance of MLD in modulating the effects of advection in the upper-ocean dynamics. This dataset describes how to re-create the results in Gao et al. (2022). The data in this collection is based on numerical simulations and sensitivity experiments in Regional Ocean–Atmosphere Model (ROAM, Perlin et al 2020.).