Capturing Oceanic Submesoscales, Stirring and Mixing with Sound and Simulations

Capturing Oceanic Submesoscales, Stirring, and Mixing with Sound and Simulations (COSSMoSS) will tackle one of the most pressing questions in oceanography: what processes drive energy transfer and property distributions within the interior ocean? The global oceans underpin our climate and biosphere by distributing and storing tracers such as heat, carbon and nutrients. Yet, little is known about the submesoscale currents (SMCs) that both stir and mix these fundamental properties, and bridge large scale flows with microscale dissipation. Characterised by spatial scales of 10 m to 100 km, and timescales of hours to weeks, SMCs are inherently difficult to observe and model.

COSSMoSS presents a pioneering experiment that will capture these unresolved interior phenomena at a global hotspot of ocean-basin interchange: the Brazil-Malvinas Confluence (BMC). Here Atlantic and Southern Ocean waters collide and exchange heat, salt, oxygen, carbon and nutrients. Sharp lateral gradients, energetic flows, and sloping topography are highly conducive to SMC generation, stirring, and mixing. Active acoustics will be combined for the first time with autonomous and vessel-based instrumentation to sample the BMC at unprecedented resolutions that capture SMCs. In parallel, observations will validate and advance cutting-edge simulations, to quantify SMC initiation, ubiquity and interactions. By revealing interior ocean dynamics in unparalleled detail, COSSMoSS will shed light on the pathways of oceanic tracer and energy exchange, leading to an improved understanding of our future biosphere and climate.

My unique combination of expertise in ocean acoustics, dynamics, and research at sea, make me the ideal leader for COSSMoSS. While driving forward a new international collaboration with project partner Prof. J. McWilliams (University of California Los Angeles), I will use my demonstrated research independence, global profile, and leadership skills to ensure its success.