在海洋边界层中反应性的快速循环
Chunxiang Ye1, Xianliang Zhou1,2, Dennis Pu2
1Wadsworth Center, New York State Department of Health, Albany, New York, USA.
Nature
|April 12, 2016
概括
在海洋大气中,颗粒酸光解迅速将酸转化为氧化物. 这一过程在海洋上特别重要,作为大气氧化剂和气溶的关键来源.
科学领域:
- 大气化学
- 环境科学
- 地质化学
背景情况:
- 氧化 (NOx) 对于大气中的氧化剂和气溶至关重要.
- 酸 (HNO3) 被认为是NOx的永久沉积物,但观察结果显示与模型存在差异.
- 为了解释NOx回收,提出了一种"再毒化"过程,但机制尚不清楚.
研究的目的:
- 研究热带层中酸回收成氧化的机制.
- 量化颗粒酸盐光解对NOx再生的贡献.
- 评估这一回收过程在海洋地区的全球意义.
主要方法:
- 在北大西洋上空进行飞机测量以收集大气数据.
- 实验室实验研究颗粒酸盐的光解速率.
- 使用主化学机制模拟化学过程的盒式计算.
主要成果:
- 通过海洋边界层的颗粒酸光解,酸迅速回收为酸 (HONO) 和氧化物 (NOx).
- 颗粒酸的光解速率明显高于气态酸 (超过两倍).
- 模型计算表明,颗粒酸盐光解在海洋环境中维持了午间观察到的HONO和NOx水平.
结论:
- 颗粒酸盐光解是热层氧化的重要来源,特别是在海洋上.
- 这种回收机制可以增强大气氧化剂和二次气溶的形成.
- 这些发现挑战了酸作为永久NOx沉积物的传统观点.
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