卫星异烯检索限制了排放和大气氧化
Kelley C Wells1, Dylan B Millet2, Vivienne H Payne3
1Department of Soil, Water, and Climate, University of Minnesota, St Paul, MN, USA.
Nature
|September 10, 2020
概括
全球卫星测量显示出异二烯排放和大气氧化模式. 这些发现挑战了现有的模型, 突出了亚马逊地区低估的氧化物排放量和非洲南部不可预测的热点.
科学领域:
- 大气化学
- 遥感技术
- 生物地化学循环
背景情况:
- 异烯是大气中主要的挥发性有机化合物,影响臭氧和气溶的形成.
- 准确量化异烯排放及其化学反应对于气候建模至关重要.
- 目前对异烯排放及其对大气影响的估计存在重大不确定性.
研究的目的:
- 使用跨轨红外探测器 (CRIS) 来呈现全球异烯测量结果.
- 通过结合异烯和甲卫星观测来限制异烯排放和大气氧化.
- 根据卫星数据评估当前的化学模型,并确定异热点的差异.
主要方法:
- 利用跨轨红外探测器 (CRIS) 的卫星数据进行全球异烯测量.
- 将异烯与甲 (一种氧化产物) 的测量结合起来,以推断排放和化学性质.
- 分析了关键的异烯排放区域的数据,并与模型预测进行了比较.
主要成果:
- 卫星衍生的异烯-甲关系与当前的异烯-基 (OH) 化学反应一致.
- 在低氧化物度下没有发现OH回收的证据.
- 在亚马逊地区鉴定出因低估自然氧化排放导致OH和异的差异.
- 在非洲南部发现了重要的异热点.
- 多年分析表明厄尔尼诺/南方振荡对跨年异烯变性的影响.
结论:
- 卫星观测为量化大气中异二烯排放和化学物质提供了强大的工具.
- 目前的模型需要改进,特别是在氧化物排放及其对异烯的影响方面.
- 确定了以前未知的异烯排放源和区域差异,改善了全球大气模型.
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