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arXiv · 1707.03356

Jupiter's South Equatorial Belt cycle in 2009-2011: II, The SEB Revival

Abstract

A Revival of the South Equatorial Belt (SEB) is an organised disturbance on a grand scale. It starts with a single vigorous outbreak from which energetic storms and disturbances spread around the planet in the different zonal currents. The Revival that began in 2010 was better observed than any before it. The observations largely validate the historical descriptions of these events: the major features portrayed therein, albeit at lower resolution, are indeed the large structural features described here. Our major conclusions about the 2010 SEB Revival are as follows, and we show that most of them may be typical of SEB Revivals. 1) The Revival started with a bright white plume. 2) The initial plume erupted in a pre-existing cyclonic oval ('barge'). Subsequent white plumes continued to appear on the track of this barge, which was the location of the sub-surface source of the whole Revival. 3) These plumes were extremely bright in the methane absorption band, i.e. thrusting up to very high altitudes, especially when new. 4) Brilliant, methane-bright plumes also appeared along the leading edge of the central branch. Altogether, 7 plumes appeared at the source and at least 6 along the leading edge. 5) The central branch of the outbreak was composed of large convective cells, each initiated by a bright plume, which only occupied a part of each cell, while a very dark streak defined its west edge. 6) The southern branch began with darkening and sudden acceleration of pre-existing faint spots in a slowly retrograding wave-train. 7) Subsequent darker spots in the southern branch were complex structures, not coherent vortices. 8) Dark spots in the southern branch had typical SEBs jetstream speeds but were unusually far south....

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John H. Rogers. 2017-07-11. Jupiter's South Equatorial Belt cycle in 2009-2011: II, The SEB Revival. https://arxiv.org/abs/1707.03356

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