Infrared Characterisation of Jupiter's Equatorial Disturbance Cycle

Abstract

We use an infrared dataset captured between 1984 and 2017 using several instruments and observatories to report five rare equatorial disturbances that completely altered the appearance of Jupiter's Equatorial Zone (EZ): the clearance of tropospheric clouds revealed a new 5-$\mu$m-bright band encircling the planet at the equator, accompanied by large 5-$\mu$m-bright filaments. Three events were observed in ground-based images in 1973, 1979 and 1992. We report and characterize for the first time the entire evolution of two new episodes of this unusual EZ state that presented their maximum 5-$\mu$m-brightness in December 1999 and February 2007, coinciding with a brown coloration south of the equator and with large bluish filaments and white plumes in the northern EZ at visible wavelengths. We characterize their typical infrared-bright lifetimes of 12-18 months, with possible periodicities of 6-8 or 13-14 years. We predict that a full-scale equatorial disturbance could occur in 2019-21.

References in corpus (4)

• The source of widespread 3-$\mu$m absorption in Jupiter's clouds: Constraints from 2000 Cassini VIMS observations
• Jupiter's North Equatorial Belt expansion and thermal wave activity ahead of Juno's arrival
• Cycles of Activity in the Jovian Atmosphere
• Atmospheric waves and dynamics beneath Jupiter's clouds from radiowavelength observations

Cited by in corpus (4)

• Colour and Tropospheric Cloud Structure of Jupiter from MUSE/VLT: Retrieving a Universal Chromophore
• Jupiter's Equatorial Plumes and Hot Spots: Spectral Mapping from Gemini/TEXES and Juno/MWR
• Vertically-resolved observations of Jupiter's quasi-quadrennial oscillation from 2012 to 2019
• Jupiter's cloud-level variability triggered by torsional oscillations in the interior