在有机气溶上形成云滴的界面机制
Christopher R Ruehl1, James F Davies2, Kevin R Wilson1
1Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA. chris.ruehl@arb.ca.gov krwilson@lbl.gov.
概括
有机气溶通过改变水活动影响云形成. 新的研究表明,这些气溶形成的云滴比预测更大,这表明需要压缩膜模型来解释云凝聚核的活动.
科学领域:
- 大气化学
- 云物理
- 气溶科学
背景情况:
- 精确的气溶云相互作用模型需要精确的云凝聚核 (CCN) 活动参数.
- 目前的模型通常假设有机气溶溶解,降低水活动以影响CCN形成.
研究的目的:
- 研究有机气溶的CCN活动,并确定控制云滴形成的机制.
- 确定现有的模型是否准确地预测有机气溶颗粒的液滴激活直径.
主要方法:
- 在CCN激活时测量二碳酸和二次有机气溶与硫酸混合的滴径.
- 观察到的激活直径与假设有机物种大量溶解的模型的预测进行比较.
主要成果:
- 观察到的液滴激活直径比预测的大量溶解模型大4060%.
- 这种差异表明需要修改云滴形成模型的机制.
结论:
- 一个压缩膜模型,考虑表面张力压缩的界面有机分子,准确地解释了观察到的更大的滴滴激活直径.
- 这种新的理解提高了气溶与云相互作用的物理准确性.
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