Turbulent mixing in the Indonesian throughflow exit passages, the Lesser
Sunda waters
Abstract
Turbulent kinetic energy dissipation rates in the Indonesian throughflow
(ITF) exit passages to the Indian Ocean, the Lesser Sunda waters, are
inferred from archived CTD measurements and recent high-resolution time
series data sets. Dissipation rates from archived data sets are inferred
using an improved Thorpe scale method validated against microstructure
measurements. Elevated dissipation rates
~[10-6-10-7] m2s-3 were observed in the straits,
where internal tides are generated. Tidal variations seemingly influence
the dissipation rates and diffusivities as has been suggested from the
yoyo profiling data sets. The spatial pattern of dissipation rates
inferred from the high-resolution 3D hydrodynamics model output of Nagai
et al (2015) shows a general agreement with the observations in the
location of the mixing hot spots and suggests that the M2 internal tide
is the dominant factor driving the turbulent kinetic dissipation rates
in this region. The bias in the model is possible due to the lack of
representation of the ITF and mesoscale circulation in the model.