Urban nocturnal cooling mediated by bluespace
Urban nocturnal cooling mediated by bluespace
复制标题
DOI：
10.1007/s00704-021-03727-5
复制
发表时间：
2021-08-05
影响因子：
3.4
通讯作者：
Li, Qi
中科院分区：
文献类型：
--
作者：
Cui, Yuanfeng;Hu, Leiqiu;Li, Qi
利用密集的美国中型城市气候观测网络、计算流体动力学和分析建模方法，研究了城市蓝色空间介导的空气温度和湿度的时空特征。数值模拟和观测结果均表明，城市3.5 m逐日平均气温和湿度的变化速率在日落后2 h达到峰值，而绿地逐日平均气温和湿度的变化速率随时间单调降低，表明城市湖泊的存在对城市的影响不同。由于近岸湿度较高，市区视温随距离湖泊而降低。这表明，靠近市中心的城市湖泊会因湿度升高而导致夜间降温效果恶化。最后，提出了两个分析模型来解释城市湖泊附近地表温度与大气温度的联系以及大气温度和湿度的空间变化。这些从测量网络中推断参数的简化模型与观测结果相比具有相当好的性能。与其他复杂的数值模拟相比，这些分析模型提供了另一种方法，可以很容易地评估蓝色空间对城市夜间降温的功效。
The spatiotemporal characteristics of air temperature and humidity mediated by urban bluespace are investigated using a combination of dense network of climatological observations in a medium-sized US city, computational fluid dynamics, and analytical modeling approaches. Both numerical simulation and observational results show that the rate of change of hourly averaged air temperature and humidity at 3.5 m over urban areas peaks 2 h after sunset, while it decreases with time monotonically over greenspace, indicating different impacts due to presence of urban lakes. The apparent temperature decreases with distance to lakes in urban area due to higher near-shore humidity. This highlights that urban lakes located near city center can deteriorate the nighttime cooling effects due to elevated humidity. Finally, two analytical models are presented to explain the connection between the surface and air temperature as well as the spatial variation of air temperature and humidity adjacent to the urban lakes. These simplified models with parameters being inferred from the network of measurements have reasonably good performance compared to the observations. Compared to other sophisticated numerical simulations, these analytical models offer an alternative means that is easily accessible for evaluating the efficacy of bluespace on urban nocturnal cooling.