作为冰核的固体硫酸盐气溶:为雪花云形成的途径
J P D Abbatt1, S Benz, D J Cziczo
1Department of Chemistry, University of Toronto, Toronto, ON M5S 3H6, Canada. jabbatt@chem.utoronto.ca
概括
固体硫酸气溶通过异质冰核形成,促进云的形成. 这一途径受农业氨排放的影响,通过改变云的特性和辐射强迫影响气候.
科学领域:
- 大气化学 大气化学
- 云物理 云物理
- 气候科学 气候科学
背景情况:
- 圆柱状云在地球的辐射平衡中起着至关重要的作用.
- 圆云的形成机制,特别是大陆圆云,尚未完全理解.
- 云形成中的半球间不对称性表明特定的形成路径.
研究的目的:
- 为了研究固体硫酸气溶在云形成中的作用.
- 确定这些气溶的异质冰核化是否解释了观测到的雪花云特性.
- 评估这一拟议的树形成途径对气候的影响.
主要方法:
- 在固体硫酸气溶上测量冰核的实验室测量.
- 分析形成冰的条件 (冰和度比).
- 将该机制纳入气候模型.
主要成果:
- 实验室数据支持通过固体硫酸盐喷雾剂进行异质冰核化.
- 冰的形成发生在低冰和率下,与大陆的冰形成是一致的.
- 气候模型模拟显示,这种途径产生较少,较大的冰晶,减少云的白色和长波加热.
- 该机制解释了云出现时的半球间不对称性.
结论:
- 固体硫酸盐气溶提供了重要的冰核来源,用于形成.
- 这一途径将农业氨排放与气候系统变化联系起来.
- 这种机制影响云的辐射特性,影响全球气候.
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