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创纪录的野火的辐射影响从综合地面数据的记录
Evgueni Kassianov1, Connor J Flynn2, James C Barnard3
1Pacific Northwest National Laboratory, Richland, WA, USA. Evgueni.Kassianov@pnnl.gov.
Scientific reports
|March 11, 2025
概括
野火烟雾显著减少太阳表面辐射,影响气候模型. 新的地面测量为评估这些密集的气溶效应提供了关键数据.
科学领域:
- 大气科学 大气科学
- 遥感 遥感 遥感 遥感
- 气候科学 气候科学
背景情况:
- 传统的野火辐射效应估计依赖于模型和有限的观测数据.
- 密集的野火羽毛,特别是来自强烈事件,由于数据缺口,对准确的辐射影响评估构成挑战.
研究的目的:
- 引入一种用于评估野火辐射效应的新方法,使用地面辐射和气溶光学深度 (AOD) 测量.
- 量化2020年美国西部野火产生的密集羽毛的辐射影响.
主要方法:
- 利用地面测量短波和光谱分辨率的辐射.
- 嵌入的气溶光学深度 (AOD) 数据在可见和近红外光谱范围.
- 应用了被新型观测数据所限制的辐射转移计算.
主要成果:
- 证明密集的野火羽毛大大降低了太阳表面辐射 (高达70%).
- 观察到极高的AOD值 (在500nm处超过10),遮蔽了太阳.
- 量化辐射影响相当于主要的火山爆发和大陆云.
结论:
- 这种新的方法提高了来自密的野火羽毛的辐射效应的评估.
- 基于地面的辐射和AOD数据为气候模型验证提供了关键约束.
- 野火烟雾带来了相当大的辐射力,与其他主要大气事件相美.
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