Study of veritcal coupling in the polar atmosphere by using multi instruments

2015 Fiscal Year Final Research Report

• Project/Area Number: 25287126
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Partial Multi-year Fund
• Section: 一般
• Research Field: Space and upper atmospheric physics
• Research Institution: Nagoya University
• Principal Investigator: NOZAWA Satonori 名古屋大学, 宇宙地球環境研究所, 准教授 (60212130)
• Co-Investigator(Kenkyū-buntansha): OGAWA YASUNOBU 国立極地研究所, 国際北極環境研究センター, 准教授 (00362210) ; FUJIWARA HITOSHI 成蹊大学, 理工学部, 教授 (50298741) ; TSUTSUMI MASAKI 国立極地研究所, 研究教育系, 准教授 (80280535)
• Co-Investigator(Renkei-kenkyūsha): SAITO NORIHITO 国立研究開発法人理化学研究所, 光量子工学研究領域, 上級研究員 (90333327)
• Project Period (FY): 2013-04-01 – 2016-03-31
• Keywords: 大気上下結合 / 成層圏突然昇温 / 大気重力波 / 大気潮汐波 / スポラディックナトリウム層 / ナトリウムライダー / EISCATレーダー / トロムソ

Outline of Final Research Achievements

We have studied the vertical coupling processes between atmospheres as well as between magnetosphere-ionosphere-thermosphere, mainly, based on observational data obtained with multi-instruments operated at Tromsoe (69.6N, 19.2E), Norway. Results are summarized as follows: (1) we investigated a dissipation process of a gravity wave, and proposed that the background temperature structure played a role, (2) we evaluated generation mechanisms of a sporadic sodium layer, and proposed a new generation mechanism that a normal sodium ion layer is a source for sodium atoms and the south-westward electric field played a role to transport sodium ions downward, (3) we derived a zonal wave number of semidiurnal tide during an SSW event, and pointed out discrepancy with model predictions, (4) we evaluated the derivation method of joule heating, and showed a care is needed for the derivation way by IS radar data, (5) we found sodium atom depletion due to auroral particle precipitations.

Free Research Field

超高層大気物理