Vertical turbulent exchange in the Black Sea pycnocline and its relation to water dynamics

Abstract

Estimates of vertical turbulent diffusion coefficient (K_t) in the Black Sea pycnohalocline have been obtained from data of simultaneous observations of seawater temperature, salinity, density, and horizontal current velocity, obtained in the northeastern part of the Black Sea during 2013–2014 with a moored Aqualog profiler. A Munk and Andersson (1948) type parameterization, adapted for the Black Sea environment, is proposed for calculating K_t. Strong short-period (several days) variability of turbulent exchange is revealed, induced by vertical shear variations of the current velocity.