セントヘレンズ山の噴火からのエアロゾールの特徴付け
Science (New York, N.Y.)
|February 20, 1981
まとめ
マウント・セント・ヘレンズ (Mount St. Helens) とは
科学分野:
- 地質化学 地質化学
- 大気科学 大気科学
- 火山学 火山学とは
背景:
- 火山噴火は,大気中にエアロゾルを放出します.
- エアロゾールの組成と大きさを理解することは,気候と大気の研究において極めて重要です.
研究 の 目的:
- セントヘレンズ山噴火からのエアロゾールの質量濃度,サイズ分布,形態学,元素組成を分析する.
- エアロゾールの特徴をフレーティック,フレートマグマティック,および主要な平流層の噴火から区別するために.
主な方法:
- エアロゾールの質量濃度とサイズ分布のインシト測定.
- 採取したエアロゾールサンプルの形態学および元素分析.
- 試料採取は,噴出口の近くや平流圏の羽根で実施された.
主要な成果:
- フレーティック噴火のエアロゾールは単体であり,大型のシリケート粒子が (>10マイクロメートル) 主要でした.
- フレアトマグマティックエアロゾールは,シリケート粒子と硫酸-シリケート混合物を含むマルチモダルであった.
- 大規模な噴火からのストラトスフィアのエアロゾールは,ユニモダル (<1マイクロメートル) で,主に硫酸の滴であった.
結論:
- 噴火の種類は,エアロゾールの特性に大きな影響を与えます.
- 大規模な噴火の後,硫酸エアロゾルは平流圏を支配した.
- エアロゾールの組成は噴火スタイルと大気への注入高度によって異なります.
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