基于ECOSTRESS的城市热环境昼夜空间特征分析

Spatial characteristics analysis of urban thermal diurnal environment based on ECOSTRESS

地表温度是表征城市热环境变化的重要指标,其分布信息对监测城市热环境具有重要意义。本文首先基于2018—2023年6—8月ECOSTRESS数据,通过地表温度修正得到沈阳市四环内的昼夜地表温度;然后利用均值-标准差法和空间自相关分析法对地表温度昼夜空间特征进行提取;最后结合土地利用数据,分析不同地类对地表温度空间分布的贡献度。结果表明,沈阳市四环内地表温度呈北高南低、西高东低的形式,日间和夜间地表温度差异较大。高温区主要集中在皇姑区、大东区、沈河区西部和铁西区东部,低温区和次中温区主要集中在四环边缘;人工地表类别的地表温度大多高于自然地表类别的地表温度,建筑用地类别高温区占比最多,这是地表升温的主要因素,自然地表类别是降温的主要因素;沈阳市四环内的地表温度呈空间正相关,夜间地表温度聚集程度高于日间,且具有显著性的冷热点,地表温度昼夜变化与地表温度聚集性分布特征一致。

Land surface temperature(LST)is an important index to characterize the change of urban thermal environment,and its distribution information is of great significance for monitoring urban thermal environment.Based on ECOSTRESS data from June to August from 2018 to 2023,diurnal LST in the fourth ring road of Shenyang is obtained through the correction of LST.Mean-standard deviation method and spatial autocorrelation analysis are used to extract diurnal spatial characteristics of LST,and combined with land use data,the contribution degree of different land types to the spatial distribution of land surface temperature is analyzed.As indicated by the results,the LST in the fourth ring road of Shenyang is high in the north and low in the south,and high in the west and low in the east.There is a large difference in LST between day and night.The high temperature area is mainly concentrated in Huanggu district,Dadong district,western Shenhe district and eastern Tiexi district,while the low temperature area and the middle temperature area are mainly concentrated at the edge of the fourth ring road,the artificial LST is mostly higher than the natural LST,and the high temperature area of building land category accounted for the largest proportion,which is the main factor for the warming of LST,while the natural LST is the main factor for the cooling of LST.There are significant clustering and hot spots in the fourth ring road of Shenyang,and the diurnal variation of LST is consistent with the aggregation distribution characteristics of LST.