"大気中の黒炭素の混合状態による放射線吸収の強化"に関するコメント
1Department of Civil and Environmental Engineering, Stanford University, Stanford, CA 94305-4020, USA. jacobson@stanford.edu
まとめ
混合物における黒炭 (BC) の光吸収は過小評価されている可能性があります. 気候モデルは,特に湿度が高い場合,見過ごされた光学効果のために,BC温暖化を過大評価する可能性があります.
科学分野:
- 大気科学 大気科学
- 気候モデリング
- エアロゾール光学
背景:
- ブラック・カーボン (BC) は,気候変動を大きく影響するエアロゾールである.
- 以前の研究では,BC混合物は,蒸発混合物よりもわずかにより多くの太陽光を吸収することを示唆しています.
- BCの温暖化効果を予測する気候モデルの正確性について懸念があります.
研究 の 目的:
- 混合物における黒炭 (BC) の光吸収特性を再評価する.
- 気候モデルにおけるBC温暖化の潜在的過大評価に対処するために.
- BCの放射力強迫に対する光学的焦点と湿度の影響を調査する.
主な方法:
- 異なる混合物におけるBCの光学特性の分析.
- 実験結果と気候モデルの出力との比較.
- 高い相対湿度で光学的フォーカシング効果を含める.
主要な成果:
- この研究は,Cappa et al.の発見に異議を唱える. 混合物におけるBCの光吸収についてです.
- 高い相対湿度での光学的な焦点効果と,不動の部品は,以前の解釈で省略されました.
- 気候モデルがBC温暖化を過大評価しているという結論は,この分析によって支持されていません.
結論:
- 混合物中の黒炭の光吸収は,以前から考えられていたよりも顕著である可能性があります.
- 気候モデルは,特定の光学現象が無視されたため,BCまでに温暖化を過大評価する必要はありません.
- さまざまな大気条件を考慮して,BCの放射線強制を正確に定量化するには,さらなる研究が必要です.
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