Long-wave radiative flux divergence and nocturnal cooling of the urban atmosphere
Long-wave radiative flux divergence and nocturnal cooling of the urban atmosphere
复制标题
长波辐射通量发散和城市大气夜间冷却
DOI：
10.1007/bf00229280
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发表时间：
1976
期刊：
影响因子：
--
通讯作者：
T. Oke
中科院分区：
文献类型：
--
作者：
M. Nuñez;T. Oke
本文给出了在城市峡谷内的平静无云的夜晚长波辐射通量发散的测量结果。结果表明，在峡谷-空气系统中存在三维（体积）辐射发散。结果与空气温度冷却率（能量存储变化）在峡谷。在无风无云的情况下，辐射发散是控制气温变化的主要机制。在夜晚的早期，这导致空气冷却，但通常在午夜后观察到辐射变暖。空气体积辐射发散被认为是大大低于以前观察到的屋顶以上的水平，并在农村地区。在峡谷测量的冷却速率是很差的预测表面导向的冷却方法。这再次表明了大气辐射平衡的重要性。
Results from measurements of long-wave radiative flux divergence on calm, cloudless nights from within an urban canyon are presented. Results show the existence of three-dimensional (volume) radiative divergence in the canyon-air system. The results are compared with air temperature cooling rates (energy storage change) in the canyon. With calm, cloudless conditions, radiative divergence is the dominant mechanism controlling air temperature changes. In the early part of the night this results in air cooling, but radiative warming was commonly observed after midnight. Canyon-air volume radiative divergence is found to be considerably less than that observed previously above roof-level, and in rural areas. Measured cooling rates in the canyon are poorly predicted by a surface-oriented cooling approach. This again points to the importance of the atmospheric radiation balance.