无人机热红外支持下的城市微尺度热环境模拟

随着人们对生活舒适度、身体健康要求的进一步提高，微小尺度的热环境状况日益受到关注.地表温度场模拟是研究城市微小尺度热环境的关键，采用地面有限实测资料很难满足不同下垫面地表温度模拟的精度需求.针对这一问题，本研究利用无人机搭载热红外成像仪获取南京市江宁区某大学校园内典型区域夏秋两季的地表温度数据，通过ENVI-met和PALM-4U两个数值模拟模型模拟研究区地表温度，并结合实测数据对不同地表类型及阴影遮挡下的模拟精度进行误差分析.结果表明，数值模拟结果与真实结果较为接近，能够用于高空间精度的城市微热环境研究中；模型对人造地表的模拟效果均优于自然地表，对空旷处地表的模拟效果优于非空旷处地表；两个模型均能较好模拟存在建筑物遮挡下的地表温度，但在植被遮挡下PALM-4U则无法达到ENVI-met的效果，综合模拟结果显示ENVI-met在城市微热环境模拟上的适用性优于PLAM-4U.本研究可为城市微尺度热环境高分辨率遥感研究提供参考.

Urban Micro-Scale Thermal Environment Simulation Supported by UAV Thermal Infrared Data

With further improvements to meet social requirements for healthy and comfortable living, the research of micro-scale thermal environments has been received increasing attention. The key to micro-scale thermal environment study is the underlying surface temperature field simulation, which requires high precision results. Taking a typical area of the Jiangning District, Nanjing City, as a study area, this study used a UAV equipped with a thermal infrared imager to obtain surface temperature data in summer and autumn because of the limitation of the traditional ground measurements. Then, the numerical simulation software of ENVI-met and PALM-4U were utilized to conduct the surface temperature filed simulation. The simulation results were further analyzed combined with measured data. The modeling results indicated that the numerical simulation has high spatial accuracy, which can be applied to the study of the urban micro-thermal environment. Furthermore, the simulation effect of the model on the artificial surface is better than that of the natural surface, and the simulation effect of the open surface is better than that of the non-open surface. The study also found that the simulation effect of ENVI-met under the influence of occlusion was better than that of PALM-4U. The vegetation occlusion PALM-4U was less effective than that of ENVI-met, although both models correctly predicted the ground temperature under the occlusion of buildings. The overall conclusion indicates that the applicability of ENVI-met is superior to that of PLAM-4U for urban micro-thermal environment simulation. The study can provide a reference for the high-resolution remote sensing research of urban micro-scale thermal environments.