Nightglow behavior during the 16–18 November 2001 passage of the Leonids meteor stream Original Research Article

An analysis is made of the nightglow behavior in the atomic oxygen 558 and 630 nm lines and in the spectral band of 360–410 nm over the region of East Siberia (52°N, 103°E) during the 16–18 November 2001 passage of the Leonids meteor stream. The spectral, cross-correlation and wavelet methods were used in analyzing the airglow variations. During the maximum phase of the 18 November 2001 Leonids meteor stream’s passage, time spectra of airglow variations (558 and 630 nm emissions) exhibited a change in the form of the spectral distribution function of oscillations, and an increase of the number and amplitudes of discrete frequency components in the range of short periods (5–100 min) as against the preceding days. Values of cross-correlation functions for time series of 558 and 630 nm emissions during separate time periods of 18 November 2001 were as high as ∼0.7–0.8, with time lags of 30–50 min. The characteristics of the oscillations identified in upper atmospheric emissions (amplitudes, periods, vertical phase velocities of wave disturbances) correspond to acoustic-gravity waves in the upper atmosphere. It is suggested that the enhancement of the acoustic-gravity wave amplitudes on 18 November 2001 could be caused by the Leonids meteor stream.