All Physics Faculty Publications

Title

Long-period Wave Signatures in Mesospheric OH Meinel (6,2) Band Intensity and Rotational Temperature at Mid-latitudes

Document Type

Article

Journal/Book Title/Conference

Advances in Space Research

Volume

27

Issue

6-7

Publisher

Elsevier

Publication Date

10-2001

First Page

1171

Last Page

1179

DOI

10.1016/S0273-1177(01)00153-3

Abstract

A high performance imaging system has been used to investigate the signature of long-period, ∼8-hr, wave-like oscillations evident in the OH Meinel (6,2) band emission (peak altitude ∼87 km) during the fall and early winter months. The measurements were made from two mid-latitude sites in the western USA during 1996/7. Previous investigations of the induced temperature perturbations (amplitude and phase) suggest that many of these events exhibit characteristics akin to the mid-latitude terdiurnal tide (Pendleton, 2000). To further investigate the origin of these waves we have performed an initial investigation using the Krassovsky ratio (η) method, to determine the amplitude ratio of the induced perturbations in the zenith OH emission intensity and rotational temperature and to study their phase relationship (φ). A range of values for the magnitude and phase of η were found with a mean value of |η| = 6 ± 2 (range ∼2–10), and φ = −51° ± 21° (range −11° to −94°) with the temperature perturbation always leading the intensity wave. These results are in good agreement with existing high-latitude studies of distinct 8-hr oscillations in the literature. However, comparison with realistic gravity wave and terdiurnal tidal model computations reveal a conflicting situation where the observed negative phase results point more towards a long-period gravity wave interpretation rather than a terdiurnal tide.

Comments

Published by Elsevier in Advances in Space Research.


http://www.sciencedirect.com/science/article/pii/S0273117701001533

Publisher PDF is available for download through the link above.

http://www.sciencedirect.com/science/article/pii/S0273117701001533