酸化窒素 (N2O):21世紀に排出されたオゾン層を蝕む主たる物質
A R Ravishankara1, John S Daniel, Robert W Portmann
1Chemical Sciences Division, Earth System Research Laboratory, National Oceanic and Atmospheric Administration, 325 Broadway, Boulder, CO 80305, USA. A.R.Ravishankara@noaa.gov
まとめ
酸化窒素 (N2O) は,現在,最も大きなオゾン層を破壊する排出物であり,規制されていない. N2Oの排出量を制限することで,オゾン層の回復と気候変動の緩和の両方に利益があります.
科学分野:
- 大気化学 大気化学
- オゾン層のダイナミクス
- 気候科学 気候科学
背景:
- モントリオール議定書は,オゾン層を破壊する主要物質の段階的な廃止に成功した.
- 人為的な排出は,平流層のオゾン回復に影響を及ぼし続けています.
- 酸化窒素 (N2O) は強力な温室効果ガスであり,オゾン層を破壊する物質である.
研究 の 目的:
- オゾン層を蝕む可能性 (ODP) に加重されたN2Oの排出量を,他のオゾン層を蝕む物質と比較する.
- オゾン層の回復に対するN2O排出の将来の影響を評価する.
- オゾンと気候に対するN2Oの軽減による二重の利点を評価する.
主な方法:
- オゾン層の劣化の可能性に加重された排出量計算.
- 規制されたオゾン破壊物質とのN2O排出量の比較分析.
- 21世紀を通してN2Oの影響を予測する.
主要な成果:
- 現在,N2Oはオゾン層を破壊する最も重要な単一の排出物です.
- N2Oの排出量は,21世紀を通して最大にとどまると予測されています.
- N2Oはモントリオール議定書によって規制されていません.
結論:
- 人為的なN2O排出量を制限することは,オゾン層の回復を促進するために不可欠です.
- N2O排出量の削減は,オゾン層の保護と気候変動の緩和の両方に役立つという二重の利益をもたらします.
- N2O排出量に対処することは,環境政策にとって"双赢"のシナリオです.
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