严重的光化学污染形成与强烈的HONO排放与露水和化蒸发蒸发相关
Wanyun Xu1, Ye Kuang2, Chang Liu1
1State Key Laboratory of Severe Weather, Key Laboratory for Atmospheric Chemistry, Institute of Atmospheric Composition, Chinese Academy of Meteorological Sciences, Beijing 100081, China.
The Science of the total environment
|December 16, 2023
概括
白天酸 (HONO) 的增加与小麦叶上的露水和化有关. 这种自然过程释放储存的HONO和氨 (NH3),影响大气化学和污染,特别是在寒冷的季节.
科学领域:
- 大气化学 大气化学
- 环境科学 环境科学
- 生物地质化学生物地质化学
背景情况:
- 白天的酸来源 (HONO) 仍然不太清楚,导致大气氧化能力偏差,特别是在寒冷的月份.
- 现有的HONO在北中国平原 (NCP) 的预算研究没有考虑自然沉积和释放机制.
研究的目的:
- 调查小麦叶上的露水和水作为NCP中大气HONO和氨 (NH3) 的来源的作用.
- 了解这些自然过程如何影响白天HONO度以及随后的大气光化学.
主要方法:
- 在一个农村NCP地点对大气HONO,水蒸气和NH3度的现场观测.
- 从小麦叶中收集和化学分析露水和水.
- 在叶面水中的HONO和NH3度的量化.
主要成果:
- 观察到大气中HONO和NH3的突然上升,与水蒸气含量相关.
- 叶子表面水样本显示出大量的溶解HONO (高达1.4毫克L-1) 和NH3 (高达23毫克L-1).
- 这些过程导致大气中HONO (平均为186%) 和NH3 (平均为233%) 的上午大幅增加.
结论:
- 和NH3在夜间沉积到叶子表面的水中,然后在白天释放,是这些化合物的重要,以前未知的来源.
- 这种自然机制在夜间储存大气氧化能力,并在阳光下迅速释放,加速白天的光化学和二次污染.
- 全球生态系统,通过露水和化,在大气光化学中发挥着至关重要的作用.
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