Open AccessA model of odd nitrogen in the aurorally dosed nighttime terrestrial thermosphere
Author(s) -
Dothe H.,
Duff J. W.,
Sharma R. D.,
Wheeler N. B.
Publication year - 2002
Publication title -
journal of geophysical research: space physics
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.67
H-Index - 298
eISSN - 2156-2202
pISSN - 0148-0227
DOI - 10.1029/2001ja000143
Subject(s) - radiance , thermosphere , physics , overtone , radiometer , mesosphere , atmospheric sciences , computational physics , remote sensing , environmental science , optics , spectral line , stratosphere , ionosphere , astronomy , geology
A model of the production and loss of odd nitrogen species (mainly, N( 4 S ), N( 2 D ), NO, and NO + ) and the enhanced vibration‐rotation band emission from NO in the infrared from the aurorally dosed terrestrial nighttime thermosphere is described. This model is assessed by analyzing the observations of the fundamental (Δ v = −1, ∼5.3 μm) and overtone (Δ v = −2, ∼2.7 μm) NO vibration‐rotation band limb emissions made by a Michelson interferometer and radiometer, respectively, aboard the Cryogenic Infrared Radiance Instrumentation for Shuttle (CIRRIS‐1A) experiment on the space shuttle Discovery during an auroral event. The auroral dosing along the line of sight is inferred from the 2.7‐μm radiance profiles using a self‐consistent procedure. The dosing obtained is then used in the model to predict the spectrally resolved emission in the 5.3‐μm region. The calculated overtone radiance profiles agree with the measured ones at lower tangent altitudes, where the signal‐to‐noise ratio is large. The calculation, however, underpredicts the observed radiance, both fundamental and overtone, at higher tangent altitudes by a factor of ∼3 and gives a colder rotational temperature for the rotationally hot component of the spectrally resolved emission from nascent NO. The causes of this discrepancy and its impact on the densities of the odd N species are discussed.