在中国西班纳地区对甲和糖的地面MAX-DOAS观测
Yu Zhang1, Xingwei Man1, Sanbao Zhang2
1School of Earth Sciences, Yunnan University, Kunming 650500, China.
Journal of environmental sciences (China)
|December 1, 2024
概括
生物质燃烧显著增加了Xishuangbanna的甲和glyoxal. 在大气中,甲的含量高于glyoxal,这表明大气中的寿命和来源不同.
科学领域:
- 大气化学 大气化学
- 空气污染研究研究
- 遥感 遥感 遥感 遥感
背景情况:
- 甲 (HCHO) 和糖 (CHOCHO) 是影响空气质量和气候的关键挥发性有机化合物 (VOC).
- 了解它们的垂直分布和来源对于大气建模和污染控制至关重要.
研究的目的:
- 为了确定HCHO和CHOCHO在中国西班纳的垂直分布.
- 研究生物质燃烧对HCHO和CHOCHO度及其垂直形状的影响.
- 要区分生物质燃烧和生物/人类来源的VOCs.
主要方法:
- 多轴差光学吸收光谱 (MAX-DOAS) 测量从2021年11月到2022年6月进行.
- 分析了HCHO和CHOCHO的垂直柱密度 (VCD) 和体积混合比率 (VMR).
- 为了进行比较,使用了来自卫星的TROPOMI数据.
- 草甘与甲 (R_GF) 的比率被用来识别VOC来源.
主要成果:
- 在生物质燃烧事件中,HCHO和CHOCHO度显著增加.
- MAX-DOAS测量结果与TROPOMI VCD显示出很好的一致性 (HCHO的R2=0.71,CHO的R2=0.70).
- 在燃烧过程中,HCHO主要存在于上层大气层 (400-800米),而CHOCHO则集中在下层 (0-200米).
- 这两种化合物每天在9:00和13:00达到峰值,与夜间积累和中午氧化有关.
- R_GF比率表明,在燃烧期间,生物质燃烧是主要来源,否则生物源和人为源占主导地位.
结论:
- 生物质燃烧是该地区HCHO和CHOCHO污染的主要原因,影响了它们的垂直分布.
- 似乎HCHO在大气中的寿命比CHO更长,这影响了它们各自的高度.
- 每天的变化表明积累和光化学过程的结合.
- R_GF比率有效地区分了大气层中不同的VOC排放来源.
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