[A-AS11] 成層圏・対流圏過程とその気候への影響

[AAS11-11] インドネシア上空成層圏におけるCO₂とSF₆の濃度

*菅原 敏¹、青木 周司²、森本 真司²、石戸谷 重之³、中澤 高清²、豊田 栄⁴、池田 忠作⁵、本田 秀之⁵、稲飯 洋一⁶、長谷部 文雄⁶、Putri Fanny⁷、後藤 大輔⁸ (1.宮城教育大学教育学部、2.東北大学、3.産業技術総合研究所、4.東京工業大学、5.宇宙科学研究所、6.北海道大学、7.インドネシア国立航空宇宙研究所、8.国立極地研究所)

キーワード：CO2、SF6、大気年代

Stratospheric air collections were carried out at Biak, Indonesia in February 2015, by using the compact cryogenic air sampler (J-T sampler). Eight sets of air sampler were launched from the experiment field in LAPAN observatory (001°10'32" S, 136° 06'02" E) using 4 large plastic balloons. The data obtained at 8 different altitudes will be used for elucidating the vertical structures of GHGs and their chemical processes in the TTL and the tropical stratosphere, with an average vertical resolution better than 2km. Air samples were analyzed for concentrations of CO2, CH4, N2O, and SF6 at Tohoku University and Miyagi University of Education. The concentrations of CO2 and SF6 at 29 km altitude were 392.9 ppmv and 7.5 pptv, respectively. Stratospheric CO2 and SF6 are known as the ‘clock tracer’. In this study, we estimated the mean age of air in the tropical stratosphere over Biak, and compared them with the results obtained from the previous experiments at Japan, Kiruna, and Syowa station. The CO2 concentration data was corrected for the airborne production by methane oxidation. CO2- and SF6-age were estimated by comparing the observed concentrations with the CONTRAIL data records in the tropical upper troposphere. As a result, the mean age of air was estimated to be about 3 years at 29km altitude. This value was significantly lower than those obtained from the satellite SF6 measurements.