日本地球惑星科学連合2019年大会

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[J] ポスター発表

セッション記号 A (大気水圏科学) » A-CG 大気海洋・環境科学複合領域・一般

[A-CG37] 北極域の科学

2019年5月30日(木) 13:45 〜 15:15 ポスター会場 (幕張メッセ国際展示場 8ホール)

コンビーナ:漢那 直也(北海道大学北極域研究センター)、庭野 匡思(気象研究所)、中村 哲(北海道大学大学院地球環境科学研究院)、鄭 峻介(北海道大学 北極域研究センター)

[ACG37-P10] Mass concertation and particle number of black carbon on glaciers in the eastern Alaskan Range, Alaska USA

*紺屋 恵子1Miyakawa Takuma1Takigawa Masayuki1Yamaguchi Masahiro1O'neel Shad2Truffer Martin3 (1.Japan Agency for Marine-Earth Science and Technology、2.USGS、3.University of Alaska, Fairbanks)

キーワード:black carbon、snow、glacier、Arctic、Alaska、aerosol

Black Carbon (BC) on snow reduces albedo lower and accelerates ablation. The Arctic demonstrates susceptibility to albedo feedbacks from non-local sources. We have estimated BC mass concentrations in snow from glacier surfaces (0-2 cm depth) and at subsurface (2-10 cm depth) in the Alaska range.
During April 2017, snow sampling was conducted on Gulkana, Black Rapids and Jarvis glaciers, which are all located within 50 km of each other. Between one and four sampling sites were selected at each glacier, at approximately 1500 m elevations. BC mass concentrations and particle size distributions was measured with a Single Particle Soot Photometer (SP2).
Measured BC mass concentrations are similar but less than previous studies. The mean value was about 6 µg/L and size distribution shows two modes around 0.3 and 0.7 µm. We have also measured the number of all aerosols by coulter counter and revealed that BC particles are about 1% of all aerosols.
We compared our measurements results to simulated BC deposition using the Weather Research and Forecasting model coupled to Chemistry (WRF-Chem). The simulated BC mass concentration agreed well with observed. We also reveaed by model result that contribution rate of biomass burning in Siberia was about 25 %. We will also estimate increase of surface melt rate caused by BC deposition.