酸素化された有機化合物の世界的な大きな源である太平洋のトロポスフィアの証拠
1NASA Ames Research Center, Moffett Field, California 94035, USA. hsingh@mail.arc.nasa.gov
Nature
|April 27, 2001
まとめ
酸素化された有機化合物は,南半球では非常に豊富に存在します.
科学分野:
- 大気化学 大気化学
- トロポスフィアの成分 トロポスフィアの構成
背景:
- 酸素化された有機化合物は,反応性窒素輸送,急性生成,エアロゾール形成を含む大気中のプロセスに影響を与えます.
- これらの化合物の分布と発生源,特に南半球に関する知識は限られている.
研究 の 目的:
- 熱帯太平洋上空の有酸素有機種の熱帯圏組成を特徴づけるために.
- 南半球における酸化有機化合物の豊富性と分布を調査する.
主な方法:
- 熱帯太平洋 (30°Nから30°S) 上の空中調査データ収集.
- 十数種類の酸素化化学物質 (例えば,カルボニル,アルコール,有機窒素,過酸化物) とC2-C8炭化水素の測定.
主要な成果:
- 酸素化された有機物種は,熱帯圏で非常に豊富に見られます.
- 全体として,南半球では,酸素化された種は非メタン炭化水素の5倍近く豊富である.
- 現在の大気モデルでは,これらの観測された豊富さを正確にシミュレートすることはできません.
結論:
- 酸素化された有機化合物の以前未知であった重要な源が存在する可能性が高い.
- 潜在的な源には,大気中の炭化水素の酸化,海洋の光化学的劣化,陸上の植物の排出が含まれます.
- これらの源を特定し,定量化するためにさらなる研究が必要である.
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