1991-1992年の北極圏対流層探査飛行中のオゾンとエアロゾールの変化
Science (New York, N.Y.)
|August 27, 1993
まとめ
1992年の北極の渦中の空中型ライダー測定は,ピナトゥボ山の噴火からの異なったエアロゾール分布を明らかにし,渦のダイナミクスを示しました. ヴォルテックス内で,最大23%の大きなオゾン層の減少が観察されました.
科学分野:
- 大気化学 大気化学
- ストラトスフィアの科学
- リモートセンシング (リモートセンサー)
背景:
- 1992年の空中輸送北極層ストラトスフィア探検 (AASE II) は,ピナトゥボ山噴火の影響を受けた期間に北極層のストラトスフィアを調査した.
- ストラトスフィアのエアロゾールとオゾンの相互作用を理解することは,大気の健康と気候の影響を評価するために不可欠です.
研究 の 目的:
- 1992年の冬,北極の渦の中で平流層のオゾンとエアロゾールの分布を測定するために.
- ピナトゥボ山のエアロゾールが北極の渦の動態とオゾンレベルに与える影響を分析する.
主な方法:
- エアロゾールとオゾンをインシットで測定するために,空中型ライダーシステムを利用しました.
- 1992年1月から3月にかけて北極の渦の中で観測を行った.
主要な成果:
- ピナトゥボ山のエアロゾールの分布は渦の内外ではっきりと観察され,渦のダイナミクスを強調した.
- 16 km 以下の渦に空気が誘導されている証拠は,エアロゾールの変化から推測されました.
- 渦の中で,極地層の平流層の雲や凍結した火山のエアロゾールは検出されなかった.
- 1992年1月から3月までの間,渦の内部でオゾン層の大幅な減少が観測されました (18km近くでは23%まで).
結論:
- この研究では,ピナトゥボ山のエアロゾール分布を用いて,渦のダイナミクスを成功裏に微分化しました.
- アークティック・ヴォルテックス内では,高層圏の条件と火山のエアロゾールの影響で,大きなオゾン損失が発生しました.
- 極地層の平流層雲や凍った火山のエアロゾールの欠如は,観測期間中に渦の中の特定の条件を示唆しています.
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