[A-AS03] [EE] 最新の大気科学：海大陸研究強化年－YMC

[AAS03-11] MJO上陸・QBO変調期における海大陸西岸対流圏・成層圏波動の活動状況

*山中 大学¹、荻野 慎也²、伍 培明²、浜田 純一³、横井 覚²、清木 亜矢子²、Bellenger Hugo²、井上 知栄³、森 修一²、耿 驃⁴、茂木 耕作²、勝俣 昌己⁴、米山 邦夫²、Sulistyowati Reni⁵、Lestari Sopia⁵、Syamsudin Fadli⁵ (1.海洋研究開発機構・大気海洋相互作用研究分野／神戸大学名誉教授、2.海洋研究開発機構・大気海洋相互作用研究分野、3.首都大学東京・都市環境学部・地理環境コース、4.海洋研究開発機構・地球環境観測研究開発センター、5.インドネシア技術評価応用庁)

キーワード：Indonesian maritime continent, tropo-stratosphere, atmospheric gravity-wave class , convective clouds

"Pre-Years of the Maritime Continent" 3-hourly radiosonde and weather radar observations were carried out both at and off Bengkulu in the southwestern coast of Sumatera in November-December 2015. The station on the sea side was the R/V Mirai staying at a 50 km distance from the coastline. Frequency and vertical wavenumber spectra of radiosonde wind and temperature showed generally-known red noise-like features. There were four types of disturbances categorized as the gravity-wave class: (i) lower-tropospheric sea-land breeze circulations (land- and sea-ward propagating cells composed of up- and down-ward waves); (ii) taller circulations with middle/upper-tropospheric nodes; (iii) few-day-period tropopausal Kelvin waves (only in zonal wind and temperature); and (iv) thinner lower-stratospheric inertio-gravity waves (with elliptic polarizations of horizontal winds). When an MJO landed around December 13, radar-observed diurnal-cycle rainfall associated with (i) was modified, and amplifications of (iii) and (iv) produced a strong vertical shear between the upper-tropopsheric easterly and the whole lower-to -middle stratospheric westerly. The middle-stratospheric zonal wind remains westerly since early 2015 even now (January 2017) with a modification of QBO. Subsequent observations might be discussed, upon the budgetary situation in after Japanese FY2017.