Breaking internal tides, generated by barotropic tide-topography interactions, are a primary driver of deep-ocean mixing. This study investigates how the barotropic-to-internal tide energy conversion responds to global warming using a linear model applied to coupled global climate model simulations under a high carbon emission scenario. Results project an 8% increase in high-mode internal tide energy conversion by the end of the 21st century, while low-mode conversion remains nearly unchanged. Intensified near-bottom stratification increases energy conversion for both modes, but intensified depth-averaged stratification reduces the modal horizontal wavenumber, leading to increased high-mode and decreased low-mode conversion. This implies stronger mixing over rough topography under global warming, necessitating improved parameterization in climate models for accurate future climate projections.

Zhibin Yang, Zhao Jing, Xiaoming Zhai, Clément Vic, Hui Sun, Casimir de Lavergne, Man Yuan