High-frequency surface kinetic energy in global high-resolution models
Event: 2020 Ocean Surface Topography Science Team Meeting (virtual)
Session: Tides, internal tides and high-frequency processes
Presentation type: Type Forum only
Kinetic energy (KE) at the sea surface (0 m) and 15 m is compared between high-resolution global simulations (the HYbrid Coordinate Ocean Model (HYCOM) and the Massachusetts Institute of Technology general circulation model; MITgcm) and observations from undrogued and drogued drifters. Kinetic energy is divided into low-frequency (<0.5 cpd), diurnal, semi-diurnal, and near-inertial bands. In the semi-diurnal band, KE from MITgcm is too high, while that from HYCOM lies closer to the drifters due to the inclusion of a parameterized topographic internal wave drag. In the near-inertial band, KE from MITgcm is too low, while the HYCOM simulations lie closer to observations due to more frequently updated atmospheric forcing fields. Both models display slightly greater energy at 0 m than at 15 m in the near-inertial, diurnal, and low-frequency bands, and little difference in the semi-diurnal band, in qualitative agreement with the undrogued and drogued drifter results.