Design of the NIPR trajectory model

Kinematic and isentropic trajectory models developed at the National Institute of Polar Research(NIPR) are compared with METEX developed at the Center for Global Environmental Research, National Institute for Environmental Studies(CGER/NIES). The NIPR model shows good agreement with METEX both in the kinematic and isentropic trajectories. An intercomparison between the tra-jectories computed with different datasets is also performed using the NIPR model, and shows that the accuracy of the trajectory is far more sensitive to the difference of the dataset used than to the difference of trajectory model

Dynamical response of the middle atmosphere to energetic particle precipitations in the latest reanalysis data

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

A diagnostic study of waves on the tropopause

The spatial structure and phase velocity of tropopause disturbances localized around the subpolar jet in the Southern Hemisphere are investigated using 6-hourly European Centre for Medium-Range Weather Forecasts reanalysis data covering 15 yr (1979–93). The phase velocity and phase structure of the tropopause disturbances are in good agreement with those of an edge wave vertically trapped at the tropopause. However, the vertical distribution of the ratio of potential to kinetic energy exhibits maxima above and below the tropopause and a minimum around the tropopause, in contradiction to edge wave theory for which the ratio is unity throughout the troposphere and stratosphere. This difference in vertical structure between the observed tropopause disturbances and edge wave theory is attributed to the effects of a finite-depth tropopause together with the next-order corrections in Rossby number to quasigeostrophic dynamic

リカレント形ニューラルネットワークの収束制御方法とパターン写像への応用

取得学位：博士(工学)，学位授与番号：博甲第228号，学位授与年月日：平成9年9月30日,学位授与年：199

Ion temperature and velocity variations in the D- and E-region polar ionosphere during stratospheric sudden warming

The Tenth Symposium on Polar Science/Ordinary sessions: [OS] Space and upper atmospheric sciences, Wed. 4 Dec. /Entrance Hall (1st floor) at National Institute of Polar Research (NIPR

An analysis on tropospheric horizontal wind variability over Syowa Station, Antarctica using radiosonde observation data

第6回極域科学シンポジウム[OM] 極域気水圏11月16日（月）　統計数理研究所 セミナー室2（D304

Current status and future plan of the Program of the Antarctic Syowa MST/IS radar (PANSY)

The Tenth Symposium on Polar Science/Special session: [S] Future plan of Antarctic research: Towards phase X of the Japanese Antarctic Research Project (2022-2028) and beyond, Tue. 3 Dec. / 2F Auditorium, National Institute of Polar Researc

ナンキョク オゾンホール カイフク ジ ノ ユソウ コンゴウ カテイ

第44次日本南極地域観測隊は,南極オゾンホールの形成過程に加え,その消滅過程の時間発展とメカニズムを明らかにすることを目的として,2003年6月～ 2004年1月にかけて南極昭和基地(69.0゜S,39.6゜E)でオゾンゾンデ集中観測を行った.上記オゾンゾンデデータと衛星観測データを用いた解析から,極渦崩壊前からブリューワー・ドブソン循環の下降流と中緯度との大気交換による極渦内のオゾン回復が始まっていることがわかった.また,波数1の準停滞性プラネタリー波の活動により,極渦内のオゾン回復の様相が経度によって大きく異なることがわかった.さらに,オゾンホール内に見られるオゾン増大層の解析から,極渦境界領域起源の空気塊が頻繁にオゾンホール内に流入していたことも明らかとなった.The 44th Japanese Antarctic Research Expedition (JARE-44) performed intensive ozonesonde observations at Syowa Station (69.0゜S, 39.6゜E) from June 2003 through January 2004 to clarify the time evolution and mechanism of the Antarctic ozone hole dissipation as well as its formation. From analysis of the ozonesonde and satellite observational data, it was found that ozone concentration inside the Antarctic ozone hole began to increase due to the Brewer-Dobson circulation and the lateral mixing between inside and outside the polar vortex even before its breakup. In addition, the ozone increase was dependent on longitude because of the zonal wavenumber 1 quasi-stationary planetary waves. It is also reported that the ozone enhanced layers frequently observed inside the Antarctic ozone hole mostly originated from the vortex boundary region

A new method to estimate total momentum fluxes

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14日（月） 国立極地研究所 2階大会議