The breaking of internal waves results in diapycnal mixing which plays an important role in different climate relevant processes such as the transport of heat, freshwater, nutrients, pollutants, and dissolved gases. Thus, it is necessary to study the physics that drives diapycnal mixing to adequately represent the ocean's role in the climate system and to construct realistic climate models. Approximately 2 TW are needed to maintain the abyssal stratification of which internal tides contribute the main share, about 0.5-1.5 TW

Internal gravity waves are disturbances that occur in the stratified ocean and can travel hundreds to thousands of kilometers away from their generation sites (e.g., Alford, 2003b). Internal wave breaking leads to turbulent diapycnal mixing, which plays an important role in different climate relevant processes, such as the transport of heat, freshwater, nutrients, pollutants, and dissolved gases (e.g., MacKinnon et al., 2017). Diapycnal mixing is thought to provide considerable energy to maintain the abyssal stratification and is a major driver of the global meridional overturning circulation (MOC) (Munk & Wunsch, 1998;Wunsch & Ferrari, 2004). It has been demonstrated that the global MOC is sensitive to the strength and spatial distribu-

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<p>Low mode internal waves in the stratified ocean are generated by the interaction between barotropic tides and seafloor topography and by the wind field in the near-inertial range. They are crucial for interior mixing and for the oceanic energy pathways, since they carry a large portion of the energy of the entire internal wave field. Long-term observations of energy fluxes of internal waves are sparse. The aim of this work is to study the temporal variability of wind generated low mode near-inertial internal waves inside an internal tide beam emanating from seamounts south of the Azores. For this, 20 months of consecutive mooring observations are used to calculate the mode 1 and mode 2 near-inertial energy fluxes as well as kinetic and potential energies. The gathered time series of near-inertial internal wave energy flux is not steady due to its intermittent forcing and is neither dominated by either mode 1 or mode 2. It shows a peak induced by a distinct strong wind event which is directly linked to wind-power input into the mixed layer north-east of the mooring location, and allows a comparison between the wind event and a background state. Furthermore, indications of non-linear interactions of the near-inertial waves with the internal tides in the form of resonant triad interaction and non-linear self-interaction have been found. This study provides new insights on the relative importance of single wind events and reinforces the assumption of a global non-uniform distribution of near-inertial energy with emphasis in regions where these events occur often and regularly. It furthermore displays its importance to be adequately incorporated into ocean general circulation models and in generating ocean mixing estimates by near-inertial waves as a similarly important component next to the internal tides.</p>