气候变化领域集成服务门户(CCPortal): A Mechanism for the STEVE Continuum Emission

CCPortal

DOI	10.1029/2020GL087102
	A Mechanism for the STEVE Continuum Emission
	Harding B.J.; Mende S.B.; Triplett C.C.; Wu Y.-J.J.
发表日期	2020
ISSN	0094-8276
卷号	47 期号:7
英文摘要	We describe a mechanism to explain the subauroral emission feature called STEVE (Strong Thermal Emission Velocity Enhancement), with a focus on its continuum spectrum. Spacecraft observations show that emissions co-occur with typically invisible plasma flows known as subauroral ion drifts. If these flows are fast enough, nitrogen molecules are vibrationally excited by collisions with ions, overcoming the activation energy of the N2+O→NO+N reaction. The resulting NO combines with ambient O, producing NO2 and spectrally broad light. Importantly, this mechanism also produces N, which reduces the lifetime of NO from hours to seconds and thus explains why the emission is confined to a discrete arc. The predicted emission altitude ((Formula presented.) 130 km) and occurrence conditions ((Formula presented.) 4-km/s flows) match well with observations. We simulate this mechanism using a simple photochemical model to demonstrate its validity. This mechanism is initiated by fast ion flows and is thus distinct from auroral and airglow processes. ©2020. American Geophysical Union. All Rights Reserved.
英文关键词	Ions; Continuum emission; Continuum spectra; Occurrence conditions; Photochemical modeling; Subauroral ion drifts; Thermal emissions; Velocity enhancement; Vibrationally excited; Activation energy; activation energy; airglow; altitude; aurora; collision; emission; model validation; nitrogen; simulation; spacecraft
语种	英语
来源期刊	Geophysical Research Letters
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/170508
作者单位	Space Sciences Laboratory, University of California, Berkeley, CA, United States
推荐引用方式 GB/T 7714	Harding B.J.,Mende S.B.,Triplett C.C.,et al. A Mechanism for the STEVE Continuum Emission[J],2020,47(7).
APA	Harding B.J.,Mende S.B.,Triplett C.C.,&Wu Y.-J.J..(2020).A Mechanism for the STEVE Continuum Emission.Geophysical Research Letters,47(7).
MLA	Harding B.J.,et al."A Mechanism for the STEVE Continuum Emission".Geophysical Research Letters 47.7(2020).