森林中的新颗粒物形成受到异二烯排放的抑制
Astrid Kiendler-Scharr1, Jürgen Wildt, Miikka Dal Maso
1Institut ICG-2, Troposphäre. a.kiendler-scharr@fz-juelich.de
Nature
|September 18, 2009
概括
异烯是一种常见的植物排放物,通过与基基发生反应,显著抑制新颗粒的形成. 这一发现有助于解释气溶事件的季节性变化,并可能影响气候模型.
科学领域:
- 大气化学 大气化学
- 气候科学 气候科学
- 环境科学 环境科学
背景情况:
- 来自植物的挥发性有机化合物 (VOC) 影响有机气溶的形成和气候辐射强迫.
- 在北极地区的单二烯排放与新的粒子形成和负辐射强迫有关.
- 气溶增长率的季节性变化与单二烯排放相关,夏季达到峰值.
研究的目的:
- 调查异二烯对新颗粒形成的影响.
- 了解异烯对粒子核形成的影响背后的机制.
- 评估异烯对气候建模和气溶辐射强迫作用的影响.
主要方法:
- 使用植物室进行模拟实验.
- 控制异烯度和VOC混合物的变化.
- 分析颗粒数度和与OH基反应性的相关性.
主要成果:
- 异烯显著抑制新颗粒的形成,在较高度下抑制增加.
- 这种抑制主要是由于异二烯与基基 (OH) 的高反应性.
- 观察到的抑制模式与气溶核化事件的季节性变化一致,解释了夏季发生的事件较少.
结论:
- 异烯与OH的反应性在抑制新粒子形成方面发挥着至关重要的作用.
- 这些发现表明,由于气候变化而增加的异烯丰度可能会降低新的粒子形成潜力.
- 这种减少可能会减轻气溶的负辐射强迫效应,影响气候预测.
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