ストラトスフィアの火山噴火における質量独立の硫黄同位体組成
Mélanie Baroni1, Mark H Thiemens, Robert J Delmas
1Laboratoire de Glaciologie et Géophysique de l'Environnement, CNRS/Université Joseph Fourier, 38400 St. Martin d'Hères, France. baroni@lgge.obs.ujf-grenoble.fr
まとめ
南極の雪の中の質量独立硫黄同位体 (Delta33S) は,火山による平流層の現象を明らかにしている. この信頼性の高いトレーサーは,時間の経過とともに,素早く光化学的二酸化硫黄の酸化を追跡します.
科学分野:
- 地質化学 地質化学
- 大気科学 大気科学
- イソトープ地球化学 イソトープ地球化学
背景:
- 火山噴火は二酸化硫黄を平流層に注入し,大気化学に影響を与えます.
- 硫黄のイソトープ,特に質量独立分離 (Delta33S) は,大気中の過程の洞察を提供します.
研究 の 目的:
- ストラトスフィアの火山イベントのトレーサーとして,南極の雪の中でDelta33Sの有用性を調査するために.
- 火山の羽根の進化過程におけるデルタ33Sの形成の時間スケールとメカニズムを理解するために.
主な方法:
- 南極の雪層における火山硫酸塩の分析.
- 硫黄の同位体成分,特にデルタ33Sの測定.
主要な成果:
- アグング (1963) とピナトゥボ (1991) の噴火から観測されたデルタ33S信号は,南極の雪の中で観測された.
- Delta33Sのサインがポジティブからネガティブにタイムシフトしていることが示されました.
- 硫黄二酸化物を硫酸に光化学的に酸化することによって,毎月のスケールで急速なDelta33S形成が示されています.
結論:
- 南極の雪の中のデルタ33Sは,平流圏の火山の出来事を記録するための信頼できるトレーサーです.
- 観測されたデルタ33Sの変異は,大気中の急速な光化学的プロセスを確認しています.
- 再現可能なDelta33Sの結果は,火山の大気中のプロセスを特定するためにその使用を検証します.
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