Atmosphere Ocean Science Colloquium

Analytical Model for Internal Wave Generation Using the Characteristic Method

Speaker: Leo Maas, Stony Brook University

Location: Warren Weaver Hall 1302

Date: Wednesday, November 18, 2015, 3:30 p.m.


In a stratified sea, internal tides are supposedly generated when tides pass over irregular topography. For any given frequency in the internal wave band, however, an infinite number of exceptional topographies exist for which there is no conversion of the surface tide. This "stealth-like" property of the topography is due to a subtle annihilation of the internal waves generated during the surface tide's passage over such exceptional bottoms. A lab-experiment confirms this property. However, for any such 'conversionless' topographies, changing the surface tide's frequency subsequently does lead to tidal conversion. The upshot of this is that tides passing over an irregular bottom are for a substantial part trapped to this irregularity, and only partly converted into freely propagating internal tides. An analytical model, employing characteristics, can be used to compute the trapped and freely propagating parts.