Planetary Sciences Editors' Highlights

Earth-like Oscillations Detected in Saturn’s Stratosphere

By comparing Cassini observations spanning ten years, Saturn’s equatorial oscillation is shown to have similarities to Earth’s Quasi-Biennial Oscillation and Semi-Annual Oscillation.

Source: Journal of Geophysical Research: Planets


Investigations of planetary atmospheric dynamics are challenging because data must be collected over long time spans to identify oscillation frequencies and forcing mechanisms. Guerlet et al. [2018] use observations by the Cassini/CIRS limb data spanning ten years to study Saturn’s stratospheric equatorial oscillation (SEO). They demonstrate that large scale waves may play an important role in driving the SEO. Similarities are found to Earth’s Quasi-Biennial Oscillation (QBO) and semi-annual oscillation (SAO), a remarkable demonstration of comparative planetology. Because of the slowly evolving dynamical processes involved, only a long time-scale mission like Cassini could accomplish such a feat.

Citation: Guerlet S., T. Fouchet, A. Spiga, F.M. Flasar, L.N Fletcher, B. Hesman, and N. Gorius [2018], Equatorial oscillation and planetary wave activity in Saturn’s stratosphere through the Cassini epoch, Journal of Geophysical Research: Planets, 123

—Sabine Stanley, Editor, JGR: Planets

© 2018. The authors. CC BY-NC-ND 3.0