基于MODIS数据的盐城市热岛效应特征分析

Characteristic Analysis of Heat Island Effect in Yancheng Based on MODIS Data

根据盐城市2017年MOD11A2地表温度数据,结合FROM-GLC10地表覆盖类型数据以及MOD15A2叶面积指数LAI数据对其热岛效应的特性进行具体分析。结果表明:(1)白天城市用地的平均地表温度高于其他地表覆盖类型,并且无季节性差异,其中夏季为33.2℃,而河流区域平均地表温度最低,其中冬季为9.1℃。(2)不同地表覆盖类型对缓解城市热岛效应的能力存在一定差异,其中河流起主导的降温作用。(3)热岛强度在夏季表现最明显,春季其次,秋冬两季不够显著,另外夜间城市热岛效应基本消失。(4)地表温度与LAI呈负相关,夏季时植被对盐城市区的降温效果最明显,其次是春季,相关系数分别为0.579和0.528。

Combining MODIS surface temperature data,FROM-GLC10 surface cover type data,and MODIS leaf area index(LAI)data,the heat island effect characteristics in Yancheng area were studied.The results showed that:(1)The average surface temperature over urban land during the day is higher than that of other land cover types,and there is no seasonal difference.The highest average surface temperature is 33.2 ℃ in urban area in summer,while the lowest average surface temperature is 9.1 ℃over river in winter.(2) There are certain differences in the ability of different land cover types to alleviate the urban heat island effect,and rivers play a dominant role in cooling effect.(3)The intensity of heat island is the most obvious in summer,followed by spring,the autumn and winter are not significant.In addition,the urban heat island effect basically disappears at night.(4) The surface temperature is negatively correlated with LAI,among which vegetation in summer has the most obvious cooling effect on Yancheng City,followed by spring,with correlation coefficients of 0.579 and 0.528,respectively.