Glider-Based Microstructure Measurements of Enhanced Diapycnal Mixing along the Continental Slope of the Western Gulf of Mexico

Abstract

Glider-based microstructure observations combined with ship-based conductivity–temperature–depth profiles were collected on the western part of the Gulf of Mexico (GoM), within the steep continental slope region in November 2017. Dynamical processes associated with bathymetry were observed, and enhanced mixing along the continental slope was detected, with diffusivity values as high as 10−3 m2/s. Recent studies proposed a conceptual model of deep GoM circulation where deep water entering the GoM sinks and fills the deep GoM through the Yucatan Channel. We hypothesize that to retain mass balance, this continuously supplied deep water has to upwell and create intermediate water, which forms the outflow of the GoM, ventilating the deep GoM on time scales of ~100 years. The western GoM has areas with steep continental slopes, where enhanced mixing likely results in the transformation and upwelling of deep water.