Cold Smoke: smoke-induced density currents cause unexpected smoke transport near large wildfires
Cold Smoke: smoke-induced density currents cause unexpected smoke transport near large wildfires
复制标题
冷烟雾：烟雾引起的密度流导致大型野火附近出现意外的烟雾输送
DOI：
10.5194/acp-15-11513-2015
复制
发表时间：
2015
影响因子：
6.3
通讯作者：
C. Clements
中科院分区：
文献类型：
--
作者：
N. Lareau;C. Clements
抽象的。首次观测到由大火引起的烟雾致密度流。利用一台新的移动多普勒激光雷达和附加的现场测量，我们记录了一股深(~2公里)充满烟雾的密度流，它以4.5m的速度传播超过25公里，位于加利福尼亚州北部的一场森林大火附近。在这些观测的基础上，我们发现控制烟层扩散的动力学是大气边界层中有烟和无烟部分之间的差异太阳加热的结果。理论密度流速度的计算与观测传播速度符合得很好。对其他烟雾密度流的其他激光雷达和摄影记录表明，这些以前未知的现象在大型野火附近相对常见，可能导致人口稠密地区严重和意外的烟雾泛滥。
Abstract. The first observations of smoke-induced density currents originating from large wildfires are presented. Using a novel mobile Doppler lidar and additional in situ measurements, we document a deep (~ 2 km) smoke-filled density current that propagates more than 25 km at speeds up to 4.5 m s−1 near a large forest fire in northern California. Based on these observations we show that the dynamics governing the spread of the smoke layer result from differential solar heating between the smoke-filled and smoke-free portions of the atmospheric boundary layer. A calculation of the theoretical density current speed agrees well with the observed propagation speed. Additional lidar and photographic documentation of other smoke-filled density currents demonstrate that these previously unknown phenomena are relatively common near large wildfires and can cause severe and unexpected smoke inundation of populated areas.