2025/04/01 by Kenneth Larrieu, Oscar Sepúlveda Steiner, Drew M. Friedrichs +3 · 1 voice
Earth and Planetary Sciences · #Meteorological Phenomena and Simulations #Arctic and Antarctic ice dynamics #Oceanographic and Atmospheric Processes
paper · pdf · doi:10.1029/2024gl112607
Abstract This study examines data collected with an autonomous underwater glider during a period of vigorous radiatively driven convection (RDC) and low winds in deep, unstratified Lake Superior. Conductivity, temperature and depth (CTD) measurements reveal distinct convective plumes of warm downwelling water with temperature anomalies of C and width scales on the order of m, consistent with theoretical scalings for the unstratified convective regime. Shear and temperature microstructure measurements indicate turbulent kinetic energy (TKE) dissipation and temperature variance dissipation rates orders of magnitude greater in thermal plumes than laterally adjacent waters. Decay timescales of indicate highly efficient mixing is sustained throughout the night. Energetics, mixing efficiency, and constraints on convective plume scales are also discussed. These observations demonstrate that RDC can dominate vertical mixing dynamics even in deep ice‐free systems, and these systems can serve as a real‐scale laboratory for investigation of convective dynamics.