@article{oai:nipr.repo.nii.ac.jp:00004036,
 author = {Nomura, Akio and Iwasaka, Yasunobu and Fukunishi, Hiroshi and Hirasawa, Takeo and Kawaguchi, Sadao and Kano, Tetsuo},
 journal = {Proceedings of the NIPR Symposium on Upper Atmosphere Physics},
 month = {Feb},
 note = {P(論文), Lidar measurements of the mesospheric sodium layer were made on 42 nights from April to October in 1985 during the wintering period of the 26th Japanese Antarctic Research Expedition (JARE-26) at Syowa Station, Antarctica (69°00'S, 39°35'E). This work was carried out as a part of the Middle Atmosphere Program (MAP). There were no significant seasonal variations in sodium abundance. Especially, the enhancement of abundance in winter was not observed. These results differ from those obtained at midlatitudes in the northern hemisphere. However, it is interesting that the sodium abundance oscillated with a period of about 36 days. As for the nocturnal variations of the sodium layer, the semidiurnal oscillation in the abundance was not detectable, but the wavelike structure due to gravity wave activity was frequently observed in the sodium vertical profile. Moreover, it was found that the sodium layer was perturbed during an auroral breakup event.},
 pages = {75--83},
 title = {Dynamics of the mesospheric sodium layer in Antarctica: Lidar measurements at Syowa Station, 1985},
 volume = {1},
 year = {1988}
}