生物源性排放导致海洋气溶的形成
Colin D O'Dowd1, Jose L Jimenez, Roya Bahreini
1Department of Physics, National University of Ireland, Galway, Ireland.colin.odowd@cmas.demon.co.uk
Nature
|June 7, 2002
概括
海洋藻类对碳的排放产生了对云形成至关重要的新颗粒. 这种化学物质显著影响海洋气溶和气候调节,挑战了以前关于硫酸的理论.
科学领域:
- 大气化学 大气化学
- 气候科学 气候科学
- 海洋生物学 海洋生物学
背景情况:
- 海洋气溶和云层影响地球的辐射预算,在气候调节中发挥关键作用.
- 这些粒子的形成对于海洋边界层中的云凝聚核 (CCN) 是必不可少的.
- 以前的研究表明,由海洋藻类氧化二甲基硫化物 (DMS) 产生的硫酸是主要来源,但这仍然没有得到证实.
研究的目的:
- 研究海洋新粒子形成 (NPF) 的替代途径.
- 确定来自海洋藻类的生物源性碳化合物在NPF中的作用.
- 评估化学对海洋气溶和全球辐射强迫的潜在影响.
主要方法:
- 进行了模拟沿海大气条件的雾室实验.
- 分析了海洋藻所排放的生物性碳的光解产物.
- 利用气溶形成模型来量化含蒸汽的影响.
主要成果:
- 证明了可以从可凝结的含蒸气中形成新的粒子.
- 确定这些蒸气是海洋藻所排放的碳化合物的光解产物.
- 模拟结果表明,这些蒸气在公海中的度足以影响海洋颗粒的形成.
结论:
- 海洋碳排放是海洋气溶的重要,以前被低估的来源.
- 基化学在海洋新粒子形成和云冷凝核生产中起着至关重要的作用.
- 海洋碳排放可能对全球辐射强迫和气候调节产生重大影响.
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