ストラトスフィアの水蒸気の変化は,セントヘレンズ山の噴火に関連しています
Science (New York, N.Y.)
|February 20, 1981
まとめ
航空機による測定により,セントヘレンズ山のエアロゾール羽根の中に,高い水蒸気濃度があることが明らかになった. この発見は,火山のエアロゾールと大気中の水蒸気との密接な関連を強調しています.
科学分野:
- 大気化学 大気化学
- 火山学 火山学とは
- エアロゾール科学は,
背景:
- 火山の噴火は,大気中に大量のエアロゾールやガスを放出します.
- 火山の噴火の組成を理解することは,大気の研究にとって極めて重要です.
- 水蒸気は,エアロゾール形成と大気中のプロセスにおいて重要な役割を果たします.
研究 の 目的:
- 航空機に搭載された計器を使用して,セントヘレンズ山の火山脈内の水蒸気濃度を測定する.
- 火山のエアロゾールと水蒸気との関係を調査する.
- 水蒸気混合比をプーム内およびその周辺で定量化するために.
主な方法:
- 機体の操作のために特別に設計された凍結点湿度計を使用しました.
- セントヘレンズ山の羽根を通過したNASAのU-2飛行中に測定を行った.
- 水蒸気混合比を質量で決定するためにデータを分析した.
主要な成果:
- 水蒸気とエアロゾールの羽根との強い関連が観察されました.
- 計測されたピーク水蒸気混合比率は,羽根の中で40 x 10^-6まで高かった.
- 水蒸気混合比率 (2-3 x 10^-6) は,羽根の外側において著しく低いことが判明した.
結論:
- 火山のエアロゾルの羽根は,地元の大気中の水蒸気濃度を大幅に高めることができます.
- 水蒸気は,火山の羽根の組成と行動と密接に関連しています.
- これらの発見は,大気中の輸送と火山の出来事に関連する化学を理解するための意味を持っています.
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