气候变化领域集成服务门户(CCPortal): Sustained eruptions on Enceladus explained by turbulent dissipation in tiger stripes

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DOI	10.1073/pnas.1520507113
	Sustained eruptions on Enceladus explained by turbulent dissipation in tiger stripes
	Kite E.S.; Rubin A.M.
发表日期	2016
ISSN	0027-8424
起始页码	3972
结束页码	3975
卷号	113 期号:15
英文摘要	Spacecraft observations suggest that the plumes of Saturn's moon Enceladus draw water from a subsurface ocean, but the sustainability of conduits linking ocean and surface is not understood. Observations show eruptions from "tiger stripe" fissures that are sustained (although tidally modulated) throughout each orbit, and since the 2005 discovery of the plumes. Peak plume flux lags peak tidal extension by ∼1 rad, suggestive of resonance. Here, we show that a model of the tiger stripes as tidally flexed slots that puncture the ice shell can simultaneously explain the persistence of the eruptions through the tidal cycle, the phase lag, and the total power output of the tiger stripe terrain, while suggesting that eruptions are maintained over geological timescales. The delay associated with flushing and refilling of O(1)-m-wide slots with ocean water causes erupted flux to lag tidal forcing and helps to buttress slots against closure, while tidally pumped in-slot flow leads to heating and mechanical disruption that staves off slot freezeout. Much narrower and much wider slots cannot be sustained. In the presence of long-lived slots, the 106-y average power output of the tiger stripes is buffered by a feedback between ice melt-back and subsidence to O(1010) W, which is similar to observed power output, suggesting long-term stability. Turbulent dissipation makes testable predictions for the final flybys of Enceladus by Cassini. Our model shows how open connections to an ocean can be reconciled with, and sustain, long-lived eruptions. Turbulent dissipation in long-lived slots helps maintain the ocean against freezing, maintains access by future Enceladus missions to ocean materials, and is plausibly the major energy source for tiger stripe activity.
英文关键词	Astrobiology; Icy moons; Outer Solar System; Saturn; Volcanism
语种	英语
scopus关键词	sea water; Article; astronomy; energy resource; geological time; moon; plume; priority journal; sea; space flight; water vapor
来源期刊	Proceedings of the National Academy of Sciences of the United States of America
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/159077
作者单位	Kite, E.S., Department of Geophysical Sciences, University of Chicago, Chicago, IL 60637, United States; Rubin, A.M., Department of Geosciences, Princeton University, Princeton, NJ 08544, United States
推荐引用方式 GB/T 7714	Kite E.S.,Rubin A.M.. Sustained eruptions on Enceladus explained by turbulent dissipation in tiger stripes[J],2016,113(15).
APA	Kite E.S.,&Rubin A.M..(2016).Sustained eruptions on Enceladus explained by turbulent dissipation in tiger stripes.Proceedings of the National Academy of Sciences of the United States of America,113(15).
MLA	Kite E.S.,et al."Sustained eruptions on Enceladus explained by turbulent dissipation in tiger stripes".Proceedings of the National Academy of Sciences of the United States of America 113.15(2016).