Dissipation Rate Estimates from Microstructure and Finescale Internal Wave Observations along the A25 Greenland–Portugal OVIDE Line

AbstractA total of 96 finestructure and 30 microstructure full-depth vertical profiles were collected along the A25 Greenland–Portugal Observatoire de la Variabilite Interannuelle et Decennale en Atlantique Nord (OVIDE) hydrographic line in 2008. The microstructure of the horizontal velocity was used to calculate turbulent kinetic energy dissipation rates evmp, where vmp refers to the vertical microstructure profiler. The lowest dissipation values (evmp 5 × 10−10 W kg−1) are found in the main thermocline, around the Reykjanes Ridge, and in a 1000-m-thick layer above the bottom near 48°N. The finestructure of density was used to estimate isopycnal strain and that of the lowered acoustic Doppler current profiler to estimate the vertical shear of horizontal velocities. Strain and shear were used to estimate dissipation rates eG03 (Gregg et al.) associated with the internal w...

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