人为NH3排放对上层热层气溶形成的全球影响
Christos Xenofontos1, Matthias Kohl2, Samuel Ruhl2
1Climate and Atmosphere Research Center, The Cyprus Institute, Nicosia 1645, Cyprus.
概括
人类产生的氨排放大大促进了上层大气中的颗粒形成,增加了气溶和云冷凝核. 这会影响空气质量和气候.
科学领域:
- 大气化学和物理大气化学和物理
- 气候科学 气候科学
- 气溶科学 气溶科学
背景情况:
- 农业产生的人为氨 (NH) 排放量不断增加,影响全球空气质量.
- NH3对上热层-下层平流层 (UTLS) 粒子动态和气溶效应的影响尚不清楚.
- 通过对流,NH3可以被运送到UTLS,这可能会增强新粒子形成 (NPF).
研究的目的:
- 评估人为NH3对UTLS粒子形成的全球影响.
- 量化NH3对UTLS气溶载荷和云凝聚核 (CCN) 丰度的影响.
- 评估NH3对气溶光学深度 (AOD) 和组成的影响.
主要方法:
- 使用EMAC地球系统模型进行全球模拟.
- 集成的多元组件NPF参数化来自于CERN CLOUD实验.
- 与人为NH3排放和没有人为NH3排放的比较模拟.
主要成果:
- 在UTLS中,NH3驱动的NPF由于对流运输而增加了一到三个数量级.
- 在高排放地区,气溶数量翻了一番,导致上层热层CCN度增加2.5倍.
- 人为NH3增加了总列AOD高达80%,水溶性无机离子对UTLSAOD的贡献增加了20%.
结论:
- 人为NH3显著增强UTLS粒子形成,气溶载荷和CCN生产.
- NH3排放改变了UTLS气溶成分,降低了酸和气溶中的水含量,导致气溶质量度下降.
- 这些发现凸显了人为NH3对UTLS气溶的全球实质性影响,对云形成和气候产生影响.
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