地球の大気の酸化能力:過去と将来の変化の可能性
1National Aeronautics and Space Administration (NASA) Goddard Space Flight Center, Laboratory for Atmospheres, Greenbelt, MD 20771.
まとめ
オゾン (O3),ヒドロキシルラジカル (OH),過酸化水素 (H2O2) によって引き起こされる地球の大気の酸化能力は変化しています. 産業の成長はO3とH2O2を増加させ,将来の予測はO3レベルが上昇することを示しています.
科学分野:
- 大気化学 大気化学
- 環境科学 環境科学
背景:
- 下層大気の主要な酸化物質はオゾン (O3),ヒドロキシル基 (OH),過酸化水素 (H2O2) です.
- 大気化学にとって極めて重要な地球の酸化能力は,これらの酸化物質のグローバルな負荷によって影響を受けます.
- 工業化と人口増加は,工業化以前の時代から大気中のO3前駆者を増加させた.
研究 の 目的:
- 地球の酸化能力の変化を評価するために.
- 大気中の酸化物質に対するO3前駆体排出量の増加の影響を理解する.
- オキシダントの傾向に関する現在の証拠とモデル予測をレビューする.
主な方法:
- 大気中の酸化物質に関する既存の観測データのレビュー.
- オゾン (O3),ヒドロキシルラジカル (OH),過酸化水素 (H2O2) の将来の傾向に関するモデル予測の分析.
主要な成果:
- オゾン (O3) の濃度が地域的に増加しており,過酸化水素 (H2O2) の増加も考えられます.
- モデルは,今後50年間,毎年0.31%のトロポスフィアのO3増加を継続すると予測しています.
- ヒドロキシルラジカル (OH) と過酸化水素 (H2O2) の傾向は依然として不確実であり,ポジティブとネガティブの両方の変化の可能性があります.
結論:
- 証拠は,特にオゾン (O3) に関する大気の酸化能力の変化を示唆しています.
- O3前駆体における継続的な増加は,大気中の酸化物質の継続的なモニタリングとモデリングを必要とします.
- グローバルな大気モデルの検証は,将来の研究にとって重要な分野であり続けています.
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