基于landsat8数据京沪穗地表热环境评估研究

STUDY ON THE SURFACE THERMAL ENVIRONMENTAL ASSESSMENT IN BEIJING-SHANGHAI-GUANGZHOU BASED ON LANDSAT8 DATA

为了揭示快速城市化地区热环境的特点,以京沪穗为研究区,利用landsat8和GDEM数据,分别对3个城市的热环境进行分析,并对北京市进行下垫面分类,分析了不同下垫面对地表温度的影响,研究了北京市DEM和归一化植被指数与地表温度的关系。结果表明:地表温度与归一化植被指数和海拔高度均表现为明显的负相关关系,R2分别为0.651和0.580。北京、上海和广州均存在不同程度的热岛效应,热岛主要存在于城市建成区,并由市辖区向外辐散。上海市强热岛面积比例最大,广州市强热岛面积比例最小,热环境优劣顺序为广州、北京、上海。

In order to reveal the characteristics of rapid urbanization areas thermal environment,Beijing,Shanghai and guangzhou were selected as the study areas. We used the data of GDEM and landsat 8 to analyze the thermal environment of three cities respectively,classified the underlying surface in Beijing,analyzed the influence of different underlying surface on land surface temperature,and studied the relationship between DEM of Beijing and normalized difference vegetation index and surface temperature. The results showed that： The surface temperature and normalized difference vegetation index or altitude showed a significant negative correlation,R2 was 0. 651 and 0. 580 respectiveby. Beijing,Shanghai and Guangzhou showed varying degrees of heat island effect,and heat island exisited mainly in the urban area and municipal area divergence out wards. Strong heat island area in Shanghai accounted for the largest proportion,strong heat island area in Guangzhou accounted for the smallest proportion. The order of the thermal environment was Guangzhou,Beijing,Shanghai.