人為的なクロロフッロメタンによってストラトスフィアのオゾン層が破壊される
Science (New York, N.Y.)
|September 27, 1974
まとめ
人造のクロロフッロメタン (Chlorofluoromethanes) は,平流層のオゾンレベルに大きな影響を与える可能性があります. これらの化合物からの塩素の放出により,オゾン層の破壊率は1990年までに自然過程を上回る可能性がある.
科学分野:
- 大気化学 大気化学
- オゾン層のダイナミクス
- 環境科学 環境科学
背景:
- ストラトスフィアのオゾンは,地球上の生命を有害な紫外線から守る上で重要な役割を果たしています.
- クロロフルオロメタン (Chlorofluoromethanes,CFMs) は,様々な産業および消費者の用途で使用される合成化合物です.
- ストラトスフィアのCFMからの塩素の放出は,オゾン層の破壊の既知のメカニズムです.
研究 の 目的:
- 将来の平流層オゾン濃度に対するクロロフルオロメタンの潜在的な影響を計算する.
- 塩素触媒によるオゾン破壊の速度を評価する.
- 予測されるオゾン破壊率と天然のオゾンシンクを比較する.
主な方法:
- 大気中の化学反応をシミュレートするために計算モデルを使用した.
- ストラトスフィアのクロロフルオロメタンから塩素の放出を分析した.
- 現在のCFM使用レベルに基づいてオゾン破壊の割合を推定しました.
主要な成果:
- 計算によると,クロロフローロメタンによる平流層オゾンの大幅な将来の減少が予測されています.
- 塩素触媒によるオゾン破壊率は,天然のオゾンシンクを上回ると予測されています.
- 現在の使用シナリオでは,この値が1985年から1990年の間に到達すると予想されています.
結論:
- 人為的なクロロフッロメタン (Chlorofluoromethanes) は,平流層のオゾン層に重大な脅威をもたらす.
- 産業用化学物質によって加速されたオゾン層の破壊は,短期的な環境問題です.
- 将来のオゾン層の損傷を軽減するために,CFMの使用を緊急に検討することが正当化されています.
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