Bibliography



Notice:

  • Clicking on the title will open a new window with all details of the bibliographic entry.
  • Clicking on the DOI link will open a new window with the original bibliographic entry from the publisher.
  • Clicking on a single author will show all publications by the selected author.
  • Clicking on a single keyword, will show all publications by the selected keyword.



Found 2 entries in the Bibliography.


Showing entries from 1 through 2


2022

Seasonal Variation of Thermospheric Composition Observed by NASA GOLD

We examine characteristics of the seasonal variation of thermospheric composition using column number density ratio ∑O/N2 observed by the NASA Global Observations of Limb and Disk (GOLD) mission from low-mid to mid-high latitudes. We also use ∑O/N2 derived from the Global Ultraviolet Imager (GUVI) limb measurements onboard the Thermosphere Ionosphere Mesosphere Energetics and Dynamics (TIMED) satellite and estimated by the NRLMSISE-00 empirical model to aid our investigation. We found that the ∑O/N2 seasonal variation is hemispherically asymmetric: in the southern hemisphere, it exhibits the well-known annual and semiannual pattern, with highs near the equinoxes, and primary and secondary lows near the solstices. In the northern hemisphere, it is dominated by an annual variation, with a minor semiannual component with the highs shifting toward the wintertime. We also found that the durations of the December and June solstice seasons in terms of ∑O/N2 are highly variable with longitude. Our hypothesis is that ion-neutral collisional heating in the equatorial ionization anomaly region, ion drag, and auroral Joule heating play substantial roles in this longitudinal dependency. Finally, the rate of change in ∑O/N2 from one solstice season to the other is dependent on latitude, with more dramatic changes at higher latitudes.

Qian, Liying; Gan, Quan; Wang, Wenbin; Cai, Xuguang; Eastes, Richard; Yue, Jia;

Published by: Journal of Geophysical Research: Space Physics      Published on:

YEAR: 2022     DOI: 10.1029/2022JA030496

annual variation; GOLD observation; MSIS; seasonal variation; semiannual variation; thermosphere composition

2016

Effects of the Equatorial Ionosphere Anomaly on the Inter-Hemispheric Circulation in the Thermosphere

We investigate the interhemispheric circulation at the solstices, in order to understand why O/N2\ is larger in the northern hemisphere winter than in the southern hemisphere winter. Our studies reveal that the equatorial ionosphere anomaly (EIA) significantly impacts the summer-to-winter wind through plasma-neutral collisional heating, which changes the summer-to-winter pressure gradient, and ion drag. Consequently, the wind is suppressed in the summer hemisphere as it encounters the EIA but accelerates after it passes the EIA in the winter hemisphere. The wind then converges due to an opposing pressure gradient driven by Joule heating in auroral regions and produces large O/N2\ at subauroral latitudes. This EIA effect is stronger near the December solstice than near the June solstice because the ionospheric annual asymmetry creates greater meridional wind convergence near the December solstice, which in turn produces larger O/N2\ in the northern hemisphere winter than in the southern hemisphere winter.

Qian, Liying; Burns, Alan; Wang, Wenbin; Solomon, Stanley; Zhang, Yongliang; Hsu, V.;

Published by: Journal of Geophysical Research: Space Physics      Published on: 02/2016

YEAR: 2016     DOI: 10.1002/2015JA022169

Equatorial ionization anomaly; interhemispheric circulation; ionosphere winter anomaly; plasma-neutral collisional heating; thermosphere composition; vertical advection



  1