南極の渦中のフリーラジカル:南極のオゾン損失におけるCFCの役割
まとめ
世界のクロロフルオロ炭素の放出は,南極のオゾンホールの形成と強く関連しています. 証拠には,高塩素一酸化物 (ClO) レベルと,春の間に増加したClOと相関するオゾン層の減少が観察されています.
科学分野:
- 大気化学 大気化学
- ストラトスフィアの科学
- オゾン層の研究 オゾン層の研究
背景:
- 南極のオゾンホールは,平流層のオゾン層の断続的な枯渇です.
- クロロフルオロ炭化物 (CFC) は,オゾン層の破壊に寄与すると疑われています.
研究 の 目的:
- クロロフルオロ炭素の放出と南極のオゾンホールの間のリンクの強さを評価する.
- オゾン層の破壊における特定の化学反応の役割を裏付ける証拠を提示する.
主な方法:
- 南極の渦の中で,航空機のインシトゥー測定の分析.
- 観測されたオゾン喪失率とモデル予測の比較.
- 塩素一酸化物 (ClO) とブロミン一酸化物 (BrO) の濃度測定.
主要な成果:
- 極地渦の中で,通常より2桁高いクロリン一酸化物 (ClO) の濃度が観測された.
- オゾンホールの形成中にClO濃度の上昇と並行してオゾン濃度の減少を示したin-situ航空機データ.
- 測定されたClOおよびBrO濃度を用いた観測されたおよび予測されたオゾン損失率の間の合意.
結論:
- 証拠は,クロロフルオロ炭素の放出と南極のオゾン層の減少との関連を強く支持しています.
- 反応動力学,光化学,および激素濃度に関する理解の進歩は,このリンクを確認するために不可欠です.
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