まとめ
1982年,エル・チホン火山の噴火により,平流層の塩化水素 (HCl) が40%増加した. この研究では,火山の発生後にフッ化水素 (HF) レベルが同様の上昇していないことが観察されました.
科学分野:
- 大気化学 大気化学
- 火山学 火山学とは
- スペクトル顕微鏡検査です.
背景:
- El Chichón火山は1982年3月~4月に噴火し,大気圏にエアロゾールを注入しました.
- 火山噴火は,ハロゲン濃度を含む大気組成を変更することができます.
研究 の 目的:
- エル・チホン噴火前と後の塩化水素 (HCl) とフッ化水素 (HF) の総列量を測定する.
- ストラトスフィアのHClとHFレベルに対する火山噴出剤の影響を評価する.
主な方法:
- スペクトル観測は北緯度20~40度範囲で行われました.
- 測定は,エル・チコンの噴火の前と,噴火後3~6ヶ月間に行われました.
- データ分析は,HCl.の年間5%の世界的な世俗的な増加を説明しました.
主要な成果:
- 噴火後,塩化水素 (HCl) の総コラム量で約40%の大幅な増加が観察されました.
- このHClの上昇は,火山の噴霧によって影響を受けた地域で観察された.
- コラムに含まれるフッ化水素 (HF) の量において,同様の増加は検出されなかった.
結論:
- El Chichónの火山のエアロゾール雲は,平流層の塩化水素 (HCl) の濃度を大幅に高めました.
- 火山噴火のエアロゾールは,平流圏でのHClの放出または輸送に役割を果たしているようです.
- フッ化水素 (HF) の濃度は,火山活動によって同様の影響を受けなかった.
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