Jupiter's North Equatorial Belt expansion and thermal wave activity ahead of Juno's arrival

Abstract

The dark colors of Jupiter's North Equatorial Belt (NEB, $7-17^{\circ }$N) appeared to expand northward into the neighboring zone in 2015, consistent with a 3-5 year cycle of activity in the NEB. Inversions of thermal-IR imaging from the Very Large Telescope revealed a moderate warming and reduction of aerosol opacity at the cloud tops at $17-20^{\circ }$N, suggesting subsidence and drying in the expanded sector. Two new thermal waves were identified during this period: (i) an upper tropospheric thermal wave (wavenumber 16-17, amplitude 2.5 K at 170 mbar) in the mid-NEB that was anti-correlated with haze reflectivity; and (ii) a stratospheric wave (wavenumber 13-14, amplitude 7.3 K at 5 mbar) at $20-30^{\circ }$N. Both were quasi-stationary, confined to regions of eastward zonal flow, and are morphologically similar to waves observed during previous expansion events.

28 pages, 15 figures, published in Geophysical Research Letters

References in corpus (4)

• Moist Convection and the 2010-2011 Revival of Jupiter's South Equatorial Belt
• Jovian Temperature and Cloud Variability during the 2009-2010 Fade of the South Equatorial Belt
• Atmospheric waves and dynamics beneath Jupiter's clouds from radiowavelength observations
• Jupiter's North Equatorial Belt and Jet, I, Cyclic expansions and planetary waves

Cited by in corpus (2)

• Assessing the long-term variability of acetylene and ethane in the stratosphere of Jupiter
• Cycles of Activity in the Jovian Atmosphere