[PEM18-P03] Long-term statistical analysis of phase velocity distribution of mesospheric and ionospheric waves in airglow images obtained in Japan and Canada
Keywords:Airglow, Atmospheric gravity wave, Medium-scale traveling ionospheric disturbance
A new spectral analysis technique has been developed to obtain power spectra in the horizontal phase velocity of these waves seen in airglow images by using the 3-D FFT technique [Matsuda et al., JGR, 2014]. Takeo et al. [JGR, 2017] studied horizontal parameters of AGWs and MSTIDs over 16 years by using airglow images at wavelengths of 557.7 nm and 630.0 nm obtained at Shigaraki, Japan (34.8N, 136.1E). We have applied the same spectral analysis technique to the airglow images obtained at Rikubetsu (43.5N, 143.8E), Japan [Tsuchiya et al., JpGU Meeting, 2017].
In this study, we have also applied the 3D FFT spectral analysis technique to the 557.7 nm and 630.0 nm airglow images obtained from 2005 to 2017 at Athabasca, Canada (54.7N, 246.7E before 25 September, 2012 and 54.6N, 246.3E after 27 September, 2012). We examined similarities and differences of horizontal wave spectra between Shigaraki, Rikubetsu and Athabasca over ten years to see their dependence on locations. The propagation direction of AGWs is north and northeastward in summer and southward and westward in winter at all the three stations. This seasonal variation of zonal (east-west) AGW propagation direction is probably caused by the wind filtering of the AGWs by the mesospheric jet. We also discuss the possible cause of the common seasonal variation of meridional (north-south) AGW propagation direction in the presentation.