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Lake Iseo Field Experiment. Leticia Chamelete de Vilhena. Energy transfer. Basin-scale internal waves decay at a higher rate than can be accounted for simply by internal dissipation Other mechanisms must act to transfer energy from these basin-scale waves to turbulent scales.
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Lake Iseo Field Experiment Leticia Chamelete de Vilhena
Energy transfer • Basin-scale internal waves decay at a higher rate than can be accounted for simply by internal dissipation • Other mechanisms must act to transfer energy from these basin-scale waves to turbulent scales
High frequency waves • Ubiquitous to lakes and oceans • Exist in narrow but discrete frequency bands approaching the buoyancy frequency, N • Important in the cascade of energy to turbulent scales • Enhance dissipation and mixing, bringing significant implications to mass fluxes and bioproductivity
Nonlinear waves • 2 groups: waves described by linear stability models, and waves described by nonlinear models • Steepening timescale (Horn et al. 2001) determines when nonlinear effects are important • Moderate forcing • Layer depth ratio
Objectives • Role of nonlinear waves on the transfer of energy and resulting mixing is still incomplete • The breaking of high frequency waves and the resulting mixing may be a significant way of maintaining the lake’s productivity and the health of the ecosystem
Objectives • Document the generation of nonlinear waves in the Southern embayment of Lake Iseo • Document breaking of high frequency waves and resulting mixing • Calculate the energy flux going into high frequency waves and the dissipation in the water column
Methods • F-probe + Microstructure data • Non-hydrostatic ELCOM