日本地球惑星科学連合2018年大会

講演情報

[EJ] Eveningポスター発表

セッション記号 A (大気水圏科学) » A-AS 大気科学・気象学・大気環境

[A-AS06] 大気化学

2018年5月23日(水) 17:15 〜 18:30 ポスター会場 (幕張メッセ国際展示場 7ホール)

コンビーナ:岩本 洋子(広島大学 生物圏科学研究科)、中山 智喜(長崎大学 大学院水産・環境科学総合研究科)、豊田 栄(東京工業大学物質理工学院、共同)、江口 菜穂(Kyushu University)

[AAS06-P01] Forward and backward model analyses on high CH4 events observed over the western North Pacific

*丹羽 洋介1町田 敏暢2澤 庸介1梅澤 拓2坪井 一寛1齊籐 和幸3松枝 秀和1三枝 信子2 (1.気象研究所、2.国立環境研究所、3.気象庁)

キーワード:メタン、航空機、モデル

Methane (CH4) is one of important greenhouse gases and a large part of the global total CH4 emission exists in Asia. Over the western North Pacific, which locates at the downwind side of the Asia continent, enhanced CH4 concentrations are frequently observed not only at surface stations but also by aircraft in the mid- to upper-troposphere. Especially, high CH4 events observed by aircraft during summer are noteworthy because they are likely emitted through highly uncertain biogenic processes and such observational data could provide valuable constraints on biogenic CH4 emission estimates in inverse modeling. However, its transport mechanism and the model uncertainty should be investigated for an effective use of those observational data. In this study, we have conducted forward and backward model analyses using the atmospheric transport model NICAM-TM and its adjoint mode in order to evaluate the transport model uncertainties and also to investigate the detailed transport pathway from the continent to the western North Pacific. The aircraft observational data we use are from the research project of Comprehensive Observation Network for Trace gases by Airliner (CONTRAIL) and from the operational observation program by Japan Meteorological Agency (JMA). The CONTRAIL project uses commercial airliners connecting Japan and Australia/Bangkok, and the JMA aircraft observation is conducted with the C-130 aircraft connecting the Japan main island and Minamitorishima.