Gravitational tidal waves in Titan's upper atmosphere

Abstract Tidal waves driven by Titan's orbital eccentricity through the time-dependent component of Saturn's gravitational potential attain nonlinear, saturation amplitudes ( | T ′ | > 10 K , | u ′ | > 20 m s −1 , and | w ′ | > 5 cm s −1 ) in the upper atmosphere (⩾500 km) due to the approximate exponential growth as the inverse square root of pressure. The gravitational tides, with vertical wavelengths of ∼100–150 km above 500 km altitude, carry energy fluxes sufficient in magnitude to affect the energy balance of the upper atmosphere with heating rates ⩾ 10 −9 erg cm −3 s −1 in the altitude range of 500–900 km.

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