38 research outputs found
Horizontal phase velocity distributions of Antarctic mesospheric gravity waves observed by airglow imager network (ANGWIN)
第6回極域科学シンポジウム分野横断型セッション:[IM] 横断 中層大気・熱圏11月17日(火) 統計数理研究所 セミナー室2(D304
Characteristics of mesospheric gravity waves over Antarctica observed by Antarctic Gravity Wave Instrument Network imagers using 3-D spectral analyses
We have obtained horizontal phase velocity distributions of the gravity waves around 90 km from four Antarctic airglow imagers, which belong to an international airglow imager/instrument network known as ANGWIN (Antarctic Gravity Wave Instrument Network). Results from the airglow imagers at Syowa (69°S, 40°E), Halley (76°S, 27°W), Davis (69°S, 78°E) and McMurdo (78°S, 167°E) were compared, using a new statistical analysis method based on 3-D Fourier transform [Matsuda et al., 2014] for the observation period between 7 April and 21 May 2013. Significant day-to-day and site-to-site differences were found. The averaged phase velocity spectrum during the observation period showed preferential westward direction at Syowa, McMurdo and Halley, but no preferential direction at Davis. Gravity wave energy estimated by I’/I was ~5 times larger at Davis and Syowa than at McMurdo and Halley. We also compared the phase velocity spectrum at Syowa and Davis with the background wind field and found that the directionality only over Syowa could be explained by critical level filtering of the waves. This suggests that the eastward propagating gravity waves over Davis could have been generated above the polar night jet. Comparison of nighttime variations of the phase velocity spectra with background wind measurements suggested that the effect of critical level filtering could not explain the temporal variation of gravity wave directionality well, and other reasons such as variation of wave sources should be taken into account. Directionality was determined to be dependent on the gravity wave periods
Seasonal variation of temperature and gravity wave activities in the upper stratosphere - lower mesosphere observed by Rayleigh lidar at Syowa in 2011-2012
第3回極域科学シンポジウム 横断セッション「中層大気・熱圏」 11月26日(月)、27日(火) 国立極地研究所 2階ラウン
昭和基地高機能ライダーの機能拡張のための波長可変共鳴散乱ライダー開発の現状
第6回極域科学シンポジウム分野横断型セッション:[IM] 横断 中層大気・熱圏11月17日(火) 国立極地研究所1階交流アトリウ
昭和基地レイリー/ラマンライダーライダーで観測された高度15-70kmの重力波活動度
第6回極域科学シンポジウム分野横断型セッション:[IM] 横断 中層大気・熱圏11月17日(火) 統計数理研究所 セミナー室2(D304
Development of multi-wavelength resonance scattering lidar for the observations of the middle-and the upper-atmosphere interactions
第2回極域科学シンポジウム/第35回極域宙空圏シンポジウム 11月15日(火) 国立極地研究所 2階大会議室前フロ
2011-2015年の昭和基地レイリー/ラマンライダーを用いた大気温度鉛直構造の観測
第6回極域科学シンポジウム分野横断型セッション:[IM] 横断 中層大気・熱圏11月17日(火) 国立極地研究所1階交流アトリウ
Status of developing a new multi-wavelength resonance scatter lidar - improvement of Syowa lidar system -
第3回極域科学シンポジウム/第36回極域宙空圏シンポジウム 11月26日(月) 国立極地研究所 2階大会議
Seasonal variations of NO observed with a microwave radiometer at Syowa Station
第3回極域科学シンポジウム 横断セッション「中層大気・熱圏」 11月26日(月) 国立極地研究所 2階大会議