基于遥感数据的城市热岛效应研究
Study on Urban Heat Island Effect Based on Remote Sensing Data

本研究以中分辨率成像光谱仪(Moderate-Resolution Imaging Spectroradiometer，简称MODIS)逐日数据反演的地表温度产品为数据基础，基于GEE平台对地表温度数据进行单位变换、逐月均值计算等处理，采用密度分割法对地表温度进行热岛强度划分，在季节尺度上通过对地表温度进行统计分析，分析研究区热岛强度空间分布特征及其演变规律，结合土地利用数据将海口市划分为建成区–近郊区–远郊区三个典型区域，分析热岛强度的区域差异，采用相关分析方法，探讨了下垫面因素对热岛效应的影响。研究结果表明：(1) 海口市城市热岛效应2~8月逐步增强，9~1月逐步减弱，在8月达到最强，在1与12月达到最低，但在冬季城市热岛中心并不明显；(2) 海口市区温度比近郊和远郊地区温度更高，但差异不大(建成区与近郊区月均温度相差0.76℃，建成区与远郊区月均温度相差0.22℃)，热岛中心出现在市区；(3) 海口市植被覆盖度和水体指数均与热岛效应呈正相关关系。
This study is based on the daily data inversion of surface temperature products from Moderate Resolution Imaging Spectroradiometer (MODIS), and uses the GEE platform to process the surface temperature data through unit transformation and monthly mean calculation. The density segmentation method is used to divide the surface temperature into heat island intensity categories. At the seasonal scale, statistical analysis is conducted on the surface temperature to analyze the spatial distribution characteristics and evolution laws of heat island intensity in the study area. Combined with land use data, Haikou City is divided into three typical areas: built-up area, suburban area, and outer suburban area. The regional differences in heat island intensity are analyzed, and the impact of underlying surface factors on the heat island effect is explored using relevant analysis methods. The research results show that: (1) The urban heat island effect in Haikou gradually increases from February to August, gradually decreases from September to January, reaches its strongest point in August, and reaches its lowest point in January and December, but is not significant in the urban heat island center during winter; (2) The temperature in the urban area of Haikou is higher than that in the suburban and outer suburban areas, but the difference is not significant (the monthly average temperature difference between the built-up area and the suburban area is 0.76？C, and the monthly average temperature difference between the built-up area and the outer suburban area is 0.22？C). The center of the heat island appears in the urban area; (3) The vegetation coverage and water index in Haikou City are positively correlated with the heat island effect.