Orateur
Description
Oceanic and thermal tides exert a profound influence on the long-term rotational evolution of rocky planets. Oceanic tides arise from gravitational tidal forces, whereas thermal tides originate from diurnal contrasts in stellar irradiation. Both types of tide exhibit resonant behaviour, enabling substantial amplification of the induced tidal torques. Notably, tidal resonances have shaped the 4.5-billion-year evolution of Earth’s length of day, with potential implications for palaeoclimates and surface conditions. In this presentation, we examine the analogy between oceanic and atmospheric tidal responses within the framework of linear tidal theory, highlighting how resonantly excited modes depend on a limited set of fundamental physical parameters. We present several analytical results quantifying the thermotidal torque acting on rocky planets, particularly Earth, and demonstrate how coastlines influence tidal dissipation in ocean worlds.