Variations of the 630.0 nm airglow emission with meridional neutral wind and neutral temperature around midnight

Chih Yu Chiang, Sunny Wing-Yee Tam, Tzu Fang Chang

Research output: Contribution to journalArticle

Abstract

The ISUAL payload onboard the FORMOSAT-2 satellite has often observed airglow bright spots around midnight at equatorial latitudes. Such features had been suggested as the signature of the thermospheric midnight temperature maximum (MTM) effect, which was associated with temperature and meridional neutral winds. This study investigates the influence of neutral temperature and meridional neutral wind on the volume emission rates of the 630.0 nm nightglow. We utilize the SAMI2 model to simulate the charged and neutral species at the 630.0 nm nightglow emission layer under different temperatures with and without the effect of neutral wind. The results show that the neutral wind is more efficient than temperature variation in affecting the nightglow emission rates. For example, based on our estimation, it would require a temperature change of 145 K to produce a change in the integrated emission rate by 9.8 km-photons cm-3 s-1, while it only needs the neutral wind velocity to change by 1.85 m-1 s-1 to cause the same change in the integrated emission rate. However, the emission rate features a local maximum in its variation with the temperature. Two kinds of tendencies can be seen regarding the temperature that corresponds to the turning point, which is named the turning temperature (Tt) in this study: firstly, Tt decreases with the emission rate for the same altitude; secondly, for approximately the same emission rate, Tt increases with the altitude.

Original languageEnglish
Pages (from-to)1471-1481
Number of pages11
JournalAnnales Geophysicae
Volume36
Issue number5
DOIs
Publication statusPublished - 2018 Oct 26

Fingerprint

airglow
temperature
nightglow
wind velocity
rate
payloads
tendencies
signatures

All Science Journal Classification (ASJC) codes

  • Astronomy and Astrophysics
  • Geology
  • Atmospheric Science
  • Earth and Planetary Sciences (miscellaneous)
  • Space and Planetary Science

Cite this

@article{50b2bc335e66432b8b022e72beb6e815,
title = "Variations of the 630.0 nm airglow emission with meridional neutral wind and neutral temperature around midnight",
abstract = "The ISUAL payload onboard the FORMOSAT-2 satellite has often observed airglow bright spots around midnight at equatorial latitudes. Such features had been suggested as the signature of the thermospheric midnight temperature maximum (MTM) effect, which was associated with temperature and meridional neutral winds. This study investigates the influence of neutral temperature and meridional neutral wind on the volume emission rates of the 630.0 nm nightglow. We utilize the SAMI2 model to simulate the charged and neutral species at the 630.0 nm nightglow emission layer under different temperatures with and without the effect of neutral wind. The results show that the neutral wind is more efficient than temperature variation in affecting the nightglow emission rates. For example, based on our estimation, it would require a temperature change of 145 K to produce a change in the integrated emission rate by 9.8 km-photons cm-3 s-1, while it only needs the neutral wind velocity to change by 1.85 m-1 s-1 to cause the same change in the integrated emission rate. However, the emission rate features a local maximum in its variation with the temperature. Two kinds of tendencies can be seen regarding the temperature that corresponds to the turning point, which is named the turning temperature (Tt) in this study: firstly, Tt decreases with the emission rate for the same altitude; secondly, for approximately the same emission rate, Tt increases with the altitude.",
author = "Chiang, {Chih Yu} and {Wing-Yee Tam}, Sunny and Chang, {Tzu Fang}",
year = "2018",
month = "10",
day = "26",
doi = "10.5194/angeo-36-1471-2018",
language = "English",
volume = "36",
pages = "1471--1481",
journal = "Annales Geophysicae",
issn = "0992-7689",
publisher = "European Geosciences Union",
number = "5",

}

Variations of the 630.0 nm airglow emission with meridional neutral wind and neutral temperature around midnight. / Chiang, Chih Yu; Wing-Yee Tam, Sunny; Chang, Tzu Fang.

In: Annales Geophysicae, Vol. 36, No. 5, 26.10.2018, p. 1471-1481.

Research output: Contribution to journalArticle

TY - JOUR

T1 - Variations of the 630.0 nm airglow emission with meridional neutral wind and neutral temperature around midnight

AU - Chiang, Chih Yu

AU - Wing-Yee Tam, Sunny

AU - Chang, Tzu Fang

PY - 2018/10/26

Y1 - 2018/10/26

N2 - The ISUAL payload onboard the FORMOSAT-2 satellite has often observed airglow bright spots around midnight at equatorial latitudes. Such features had been suggested as the signature of the thermospheric midnight temperature maximum (MTM) effect, which was associated with temperature and meridional neutral winds. This study investigates the influence of neutral temperature and meridional neutral wind on the volume emission rates of the 630.0 nm nightglow. We utilize the SAMI2 model to simulate the charged and neutral species at the 630.0 nm nightglow emission layer under different temperatures with and without the effect of neutral wind. The results show that the neutral wind is more efficient than temperature variation in affecting the nightglow emission rates. For example, based on our estimation, it would require a temperature change of 145 K to produce a change in the integrated emission rate by 9.8 km-photons cm-3 s-1, while it only needs the neutral wind velocity to change by 1.85 m-1 s-1 to cause the same change in the integrated emission rate. However, the emission rate features a local maximum in its variation with the temperature. Two kinds of tendencies can be seen regarding the temperature that corresponds to the turning point, which is named the turning temperature (Tt) in this study: firstly, Tt decreases with the emission rate for the same altitude; secondly, for approximately the same emission rate, Tt increases with the altitude.

AB - The ISUAL payload onboard the FORMOSAT-2 satellite has often observed airglow bright spots around midnight at equatorial latitudes. Such features had been suggested as the signature of the thermospheric midnight temperature maximum (MTM) effect, which was associated with temperature and meridional neutral winds. This study investigates the influence of neutral temperature and meridional neutral wind on the volume emission rates of the 630.0 nm nightglow. We utilize the SAMI2 model to simulate the charged and neutral species at the 630.0 nm nightglow emission layer under different temperatures with and without the effect of neutral wind. The results show that the neutral wind is more efficient than temperature variation in affecting the nightglow emission rates. For example, based on our estimation, it would require a temperature change of 145 K to produce a change in the integrated emission rate by 9.8 km-photons cm-3 s-1, while it only needs the neutral wind velocity to change by 1.85 m-1 s-1 to cause the same change in the integrated emission rate. However, the emission rate features a local maximum in its variation with the temperature. Two kinds of tendencies can be seen regarding the temperature that corresponds to the turning point, which is named the turning temperature (Tt) in this study: firstly, Tt decreases with the emission rate for the same altitude; secondly, for approximately the same emission rate, Tt increases with the altitude.

UR - http://www.scopus.com/inward/record.url?scp=85055817804&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=85055817804&partnerID=8YFLogxK

U2 - 10.5194/angeo-36-1471-2018

DO - 10.5194/angeo-36-1471-2018

M3 - Article

AN - SCOPUS:85055817804

VL - 36

SP - 1471

EP - 1481

JO - Annales Geophysicae

JF - Annales Geophysicae

SN - 0992-7689

IS - 5

ER -