[12-Feb-2018] Drushka, K., Asher, B., Thompson, E.J., Iyer, S., Jessup, A.T., and Clark, D.
Presented at the 2018 Ocean Sciences MeetingA major objective of the SPURS-2 project is to understand the processes by which the patchy, shallow layers of fresher water created by rainfall on the ocean surface are transformed into the observed large-scale ocean salinity structures. Here, we focus on the specific question of the role played by turbulence in the upper meter of the ocean in mixing rain-induced fresh lenses. During the SPURS-2 cruises in 2016 and 2017, turbulence dissipation rates in the upper meter of the ocean were measured at multiple depths from the surface to one meter using the ship-based controlled flux technique and multiple turbulence sensors mounted on a towed surface-following platform, the surface salinity profiler. Along with these data, meteorological forcing and near-surface stratification in both salinity and temperature were measured. In this paper, we synthesize these observations in conjunction with the results from a 1-dimensional turbulence closure model to provide a mechanistic understanding of how turbulence controls near-surface mixing as it relates to the formation and evolution of rain-generated stratification.