从IAGOS-CARIBIC飞行实验室观察到的航行高度的航空废气气溶的特性和处理
Christoph Mahnke1, Rita Gomes1, Ulrich Bundke1
1Forschungszentrum Jülich GmbH (FZJ), Institute of Energy and Climate Research: Troposphere (IEK-8), Jülich 52428, Germany.
Environmental science & technology
|April 8, 2024
概括
航空废气气溶的特性保持一致,即使在老化的羽毛中. 这表明当前的全球模型准确地反映了飞机的颗粒数排放指数.
科学领域:
- 大气化学和物理大气化学和物理
- 航空对气候的影响.
- 气溶科学是一门气溶科学.
背景情况:
- 关于航空产生的气溶,其加工以及对云和气候的影响,仍然存在不确定性.
- 航空产生的气溶的精确性质对于评估航空业对气候的影响至关重要.
研究的目的:
- 为了描述飞机羽毛中的航空诱导的气溶特性.
- 将观察到的气溶特性与现有的排放指数数据和全球模型参数进行比较.
主要方法:
- 使用IAGOS-CARIBIC飞行实验室 (2018年7月 - 2020年3月) 分析了1100多架飞机遇到的羽毛.
- 测量气溶的特性 (混合状态,颗粒大小) 在各种高度的羽毛.
- 从老化羽毛观测中减去颗粒数排放指数 (EIs).
主要成果:
- 飞机羽毛中的气溶属性在不同高度上是一致的.
- 排气气溶仍然在外部混合,与内部混合的背景气溶不同,即使在1-3小时后.
- 在羽毛中没有观察到积累模式粒子 (>250 nm) 的增加.
- 观察到的粒子数排放指数与发动机认证值保持一致,并且在全球模型中使用的范围内.
结论:
- 航空废气气溶在羽毛膨胀期间在很大程度上保持其排放状态.
- 全球气候模型中使用的颗粒数排放指数得到了这些对老化羽毛的观测的支持.
- 进一步的研究可以通过这些验证的气溶特性来完善气候影响评估.
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