基于Landsat8卫星影像的地表温度反演及福州春季城市热岛效应分析

Land Surface Temperature Retrieval and Urban Heat Island Effect Based on Landsat8 Image in Fuzhou City

为研究福州春季城市热岛空间分布特征,利用2018年3月11日Landsat8卫星影像,运用辐射传导方程法和普适性单通道算法对研究区进行地表温度反演,采用地面气象监测站实测的气温对2种方法的反演精度进行比较,并统计分析不同行政区地表温度等级特征。结果表明,这2种方法反演的地表温度的空间分布特征基本一致,辐射传导方程法精度优于普适性单通道算法。福州存在明显的城市热岛现象,高温区及次高温区为城市热岛效应影响区域,该区域为老城区及城市扩张的城市建设区,其中高温区主要分布于福州滨海新城、闽侯县(上街镇、南屿镇、南通镇)和仓山区等新近开发建设的建筑物密集区和裸地区域,低温和次低温区主要分布于森林和水体。为缓解城市热岛现象,城市开发建设中应保持一定面积的绿地和水体。

In order to research the spatial features of urban heat island in Fuzhou City,the land surface temperature (LST) retrieval was conducted from remote sensing Landsat8 images acquired on March 11,2018 based on radioactive transfer equation algorithm and single channel method.The results were compared with the measured temperature of some meteorological stations in the study area.The levels of LST in different administrative districts were statistically analyzed.The research results showed that the spatial distribution features of LSTs from two algorithms were basically identical.However,the radioactive transfer equation algorithm was better than the single channel method.It was found that there existed obvious heat island effect in Fuzhou City.The areas with high and subhigh LSTs were located in old city zones and newly expanded city zones,which were dominant areas for heat island effect.In the view of administrative districts,areas with high LST were in Binhaixincheng,some townships of Minhou County (Shangjie,Nanyu,Nantong) and Cangshan.Areas with low LST were distributed in forest zones and water bodies,indicating that it is very important to maintain a certain area of green land and water body during city development to alleviate the phenomenon of urban heat island.