Presenter: Jonathan Nash (Oregon State University)

Description:
In an effort to expand our global database of ocean turbulence observations, sensors to directly measure microscale temperature gradient have been deployed on most GO-SHIP repeat hydrography cruises over the past eight years, providing surface to bottom cross ocean observations.  These sensors (which we call chi-pods) permit the dissipation rate of temperature variance to be computed, from which the turbulent diffusivity of heat can be estimated.  Here we present an assortment of observations from more than 10 cruises that span all major ocean basins (Atlantic, Pacific, Indian, Arctic and Southern Ocean) to demonstrate the richness of this new data set.  Patterns of mixing roughly correspond to regions of enhanced finescale strain and shear, consistent with internal wave parameterizations of mixing.  However, notable exceptions exist, and these may help us to identify dynamics that are not properly taken into account in both regional studies and climate-scale models.  Our hope is that these data will provide new insights for the community.