Internal tide mapping and predictability in an idealized configuration

Aurelien Ponte, CNRS-IFREMER-IRD-UBO, LOPS, Plouzané, France, Noe Lahaye, LOPS, IUEM, University of Brest, Brest, France, Zoé Caspar-Cohen, Ifremer, Plouzané, France and Sylvie Le Gentil, Laboratoire de Physique des Océans, Brest, France
We address our ability to map and predict low-mode internal tides in the ocean. Improving our ability to do so is relevant to wide-swath altimetry (SWOT 2021). Within idealized numerical simulations where we propagate a low-mode internal tide in a turbulent eddy field, we first quantify the sensitivity of low-mode internal pathways to the knowledge of the low-frequency flow. This quantification is a first step in order to decide whether one can hope to estimate the distribution of internal tides (stationary and non-stationary parts) operationally. We also propose a method that allows to map the distribution of the internal tide stationary part. The method relies on a dynamical model for the propagation of a low-mode coherent internal tide combined with observations of sea level and currents. Above mentioned numerical simulations are analyzed in order to assess the relevance of this method.