Estimation of Basin-scale turbulence distribution in the North Pacific Ocean using CTD-attached thermistor measurements

Abstract

AbstractA recently developed technique for microstructure measurement based on a fast-response thermistor mounted on a conductivity-temperature-depth equipment was used on eight cruises to obtain 438 profiles. Thus, the spatial distribution of turbulent dissipation rates across the North Pacific sea floor was illustrated, and was found out to be related to results obtained using tide-induced energy dissipation and density stratification. The observed turbulence distribution was then compared with the dissipation rate based on a high-resolution numerical ocean model with tidal forcing, and discrepancies and similarities between the observed and modelled distributions were described. The turbulence intensity from observation showed that the numerical model was overestimated, and could be refined by comparing it with the observed basin-scale dissipation rate. This new method makes turbulence observations much easier and wider, significantly improving our knowledge regarding ocean mixing.