Analysis Of Urban Heat Island Effect And Influencing Factors Based On Landsat Image

This paper analyzes the research status of urban heat island effect at home and abroad,and summarizes the research methods and achievements of urban heat island effect.Monitoring urban heat island effect mainly includes meteorological data comparison method,numerical simulation method and remote sensing monitoring method.Since the first observation of urban heat island effect by satellite in 1972,inversion of surface temperature by remote sensing image has gradually become the mainstream method for analyzing urban heat island effect.The research results of urban heat island effect can provide effective reference for urban planning and design,urban transformation,industrial site selection,urban green space construction,etc.This article uses the method of radiative transfer equation inversion of Tangshan city in 2000,2005,2010,2015 and 2015 as well as the surface temperature of the four seasons in 2015.Then use use the mean-standard deviation method to divide the surface temperature into low temperature,sublow medium temperature,medium temperature,subhigh temperature,high temperature and then analyze the space-time evolution of Tangshan urban heat island effect,the characteristics of the seasonal changes and land surface temperature profile structure.The results of the analysis of Tangshan urban heat island effect show that Tangshan has a very significant heat island effect,and the surface temperature fluctuates greatly with the change of the underlying surface.During the study period,the area of Tangshan heat island effect area decreased and the proportion index of urban heat island increased.On the other hand,the heat island effect of Tangshan city has seasonal regularity,which is the strongest in summer and the most obvious in winter.In order to analyze the reasons for the strengthening of Tangshan heat island,the factors affecting the heat island effect were analyzed from the underlay surface and the artificial heat.To analyze the impact of the undercoat on the urban heat island,we used the ENVI5.3random forest classification method to classify the land use status of Tangshan images at different periods.The spatial analysis tool of Arc GIS10.2 was used to superimpose land use classification map and surface temperature inversion map in space,and the size of different land temperature was statistically analyzed.The influence of human heat on the heat island effect is analyzed from two aspects of population density and per capita GDP.The population density and per capita GDP in 2015 were fitted to the area ratio of regions with different temperature levels respectively.The fitting model was selected by fitting the size of the determination coefficient R2,and the accuracy of the fitting model was evaluated.Finally,through the analysis of the factors affecting the urban heat island effect,some methods to alleviate the urban heat island effect in Tangshan city are proposed.