高層圏のハロゲンの濃度が高い場合,オゾンの減少
M J Prather1, M B McElroy, S C Wofsy
1Center for Earth and Planetary Physics, Harvard University, Cambridge, Massachusetts 02138, USA.
Nature
|November 15, 1984
まとめ
無機塩素濃度の上昇は,平流層のオゾン層を15%以上大幅に枯渇させる可能性があります. このオゾン層の減少は,クロロカーボン排出量の年間3%の増加とともに,世紀半ばまでに起こり,ブロモカーボン放出によって悪化する可能性が高い.
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:
- ストラトスフィアの化学バランスは,反応性ハロゲン化合物に対して敏感です.
- オゾン層の枯渇は地球上の生命にリスクをもたらす.
- 人為的な排出は,大気中にオゾン層を破壊する物質を導入します.
研究 の 目的:
- 低層平流層の化学構造に対する無機塩素の増加の潜在的影響を調査する.
- 塩素炭素排出によるオゾン柱密度の潜在的減少を定量化するために.
- ブロモカーボン放出がオゾン層に与える追加の影響を評価する.
主な方法:
- 下層平流圏の化学モデリング.
- 様々な排出シナリオの下でのオゾン柱密度の予測.
- ハロゲン化学の相互作用の分析.
主要な成果:
- 低層平流層の化学的性質の大きな変化は,高濃度の無機塩素で予測されています.
- オゾン柱の密度は,特定の排出条件下では15%以上減少する可能性があります.
- 産業用ブロモカーボン放出は,オゾン層の劣化を悪化させる可能性がある.
結論:
- 無機塩素濃度の上昇は,オゾン層に重大な脅威をもたらす.
- 予想されるクロロカーボン排出量の増加は,21世紀半ばまでにオゾン層の大幅な損失につながる可能性がある.
- クロロ炭化水素とブロモ炭化水素の結合効果は,平流層のオゾン回復に深刻な影響を与える可能性があります.
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