Temporal And Spatial Variation Of Heat Island Effect In Chengdu Based On MODIS Data

With the large-scale urbanization process in China, the urban heat island effect has become an important factor affecting the urban environment, and has the harm to the urban environment and human health. With the development of remote sensing technology, especially the MODIS data unique advantages can be retrieved land surface temperature, and according to the surface temperature division of heat island area, a comprehensive analysis of the heat island effect.Firstly, through the split window algorithm to construct the model inversion of Chengdu City in 2012 July 4, the surface temperature, and on this basis, combined with MODIS temperature product, in 2003 to 2014 years of MODIS data for land surface temperature retrieval, according to Chengdu City heat island area, calculate the proportion, and according to the evaluation index of heat island, on 12 years of data were heat island area of Chengdu City, the interannual and seasonal distribution rules and heat island effect evaluation. The spatial distribution of annual and seasonal heat island in Chengdu city is analyzed by the combination of the regional map of Chengdu city and the area of heat island area of Chengdu city. The value, Chengdu city class diagram and heat island area overlay, and select economy, energy consumption and other factors and heat island area value to establish a regression model to analyze the influencing factors of urban heat island effect in Chengdu City, Chengdu City DEM map, Chengdu City rainfall statistics. At last, by studying the annual heat island of Chengdu and the change of the transfer matrix of every two years, the development of the heat island in Chengdu is forecasted.Combined with the temporal and spatial variation of heat island effect of Chengdu, the influence factor of heat island effect of Chengdu, and the change of heat island effect of Chengdu city and forecast of the three aspects of the results, the countermeasures are proposed. Through the research, the concrete conclusions are as follows:(1)The heat island intensity of Chengdu from 2003 to 2014 has been reduced, but the development of the heat island is still strengthening. The autumn and winter are the key season of the development of the heat island effect in Chengdu city.(2) The heat island of Chengdu has the tendency of the transfer and diffusion. The distribution of heat island in Chengdu tends to concentrate on the breaking trend.(3) Of urban heat island effect in Chengdu City, the relative concentration of place at lower altitudes, gentle slope, the concentrated in the southeast slope, semi sunny slope, and heat island development in places where the precipitation is greater. Economic factors on the impact of the most significant, followed by energy consumption, construction land is an important factor that can influence the development of urban heat island effect in Chengdu City, green coverage has important influence to alleviate the urban heat island effect in Chengdu City.(4) The change of the heat island effect in Chengdu is mitigated and continues to mitigate the trend of the absolute measure.