Frequency spectra of tidal quantities and their components for the reference case (Table 2) and the semidiurnal tide. Top: Tidal input power (left panel) and tidally dissipated power (right panel). Bottom: Imaginary part of the quadrupolar Love number (left panel) and tidal torque exerted about the planet’s spin axis (right panel). All quantities are plotted in logarithmic scale (vertical axis) as functions of the normalised semidiurnal tidal frequency χ = (Ω − n_s) /Ω_Ε (horizontal axis). In each plot, the orange, blue and black lines designate the response of the solid part, ocean, and whole planet, respectively. Solid lines indicate decelerating tidal torque ( and 𝒯_z;2 ≤ 0) and positive tidal input power (𝒫_T ≥ 0), while dashed lines indicate accelerating tidal torque and 𝒯_z;2 > 0) and negative tidal input power (𝒫_T < 0). In the plot of the tidal torque, the magenta vertical dashed line and arrow indicate the position of the present day Earth in the spectrum and the direction of evolution of the semidiurnal tidal frequency, respectively. The red dot designates the corresponding tidal torque.