Dinora Noelia Garcia Santacruz

Spatiotemporal characteristics of the internal wave field and its parameterization in global ocean models

Small-scale turbulent mixing affects large-scale ocean processes such as the global overturning circulation but remains unresolved in ocean models. Since the breaking of internal gravity waves is a major source of this mixing, consistent parameterizations take internal wave energetics into account. The IDEMIX (Internal Wave Dissipation, Energy and Mixing) model links internal gravity wave (IGW) energy sources and dissipation and thereby provides an energetically consistent representation of wave-induced mixing and drag in ocean and atmosphere general circulation models. 

During my PhD project I will identify regional differences in the IGW spectrum, and their causes based on energy levels, spectral slopes, wavenumber scales, and energy dissipation rates from full-depth profiles of horizontal currents and stratification in combination with the shear-strain finestructure method. The hydrographic profiles come from three dynamically different regions: the subpolar North Atlantic with energetic wind-induced near- inertial waves, the western subtropical Atlantic where the strong Deep Western Boundary Current interacts with the continental slope and produces lee waves, and an area of energetic internal tides in the eastern North Atlantic. 

Further, I will analyze spatiotemporal variability in the internal wavefield and deviations from the GM (Garrett and Munk, 1972) model due to mesoscale variability, wind forcing, internal tides, swell, and wave-wave interactions inferred from mooring time series in the same regions as the full-depth hydrographic profiles. 

My PhD project is part of the TRR181 “Energy Transfers in Atmosphere and Ocean“ in the subproject dealing with gravity waves in the ocean (W4).