Influence Of Impervious Surface On Land Surface Temperature

Impervious surface is a more important part of the city sutface.With the fast development of the urbanization, the scale of the impervious surface will also change, thus bring a series of questions to even threaten. Land surface temperature (LST) is a more important parameter in studying the material exchange and energy exchange between the land and the atmosphere, a key parameter of physical course of the earth top layer in the area or global scale, an important index of monitoring the earth resource and studying the Ecological environment system of the earth's surface, it has very important function in many aspects, such as climate, hydrology, ecology, environment and military affairs.The study on the impervious surface is little in our country, it mainly concentrates on its having influence on land surface overseas.These threats includes increased stormwater runoff, reduced water quality and quantity, higher maximum summer temperatures, energy balances and microclimatic impacts, degraded and destroyed aquatic and terrestrial habitats, and the diminished aesthetic appeal of streams and landscapes, habitat degradation, loss, and fragmentation.The study on the retrieving of land surface temperature has been already quite ripe, but there is almost no study on the connection between impervious surface and land surface temperature. This paper regards Zhengzhou region as studies areas, LandsatTM/ETM+ image as main data source, other geographical information data as assistant data source, firstly manages normalized linearity spectral mixture analysis model to build end member scale image, thus gains the scale image of the impervious surface in 1988/2001.Secondly it manages mono-window algorithm to retrieve land surface temperature based on the LandsatTM/ETM+ hot infrared image, thus gains the land surface temperature image of Zhengzhou region in 1988/2001. Then it analyses the connection between impervious surface and land surface temperature, at last receives the conclusion: impervious surface and land surface temperature are the positive correlation, but the correlation coefficient is reversely small. Impervious surface has effect on land surface temperature, but the relation is indeterminate, which is difficult to express with maths model. This paper is divided into six parts altogether:In the first part, it is the part of introduction; it defines the concept of impervious surface and land surface temperature, describes the study status of the calculating impervious surface scale and retrieving land surface temperature in home and abroad.In the second part, this paper introduces the overview of studying area; through pretreating the remote sensing image, change the space precision of the pixel, and turn the pixel value into the reflectance in the top layer of aerosphere.In the third part, it describes how to build the scale image of impervious surface. Choice and drawing of the end member is the focal point in this chapter, after done that, manages normalized linearity spectral mixture analysis model to analyze the mix-pixel, builds the end member scale image, thus receives the scale image of the impervious surface.In the fourth part, introduce the relevant contents of retrieving land surface temperature emphatically. This chapter explains the principle and method of retrieving land surface temperature with hot infrared remote sensing systematically, and the retrieving algorithm based on Landsat data especially. The parameter which the mono-window algorithm needs is a key point in this chapter; combine the situation of the studying area, retrieve the land surface temperature of Zhengzhou region in 1988/2001 with mono-window algorithm.In the fifth part, analyse the influence of impervious surface on land surface temperature emphatically. Through analyzing receive conclusion: Impervious surface has effect on land surface temperature, but the relation is indeterminate; impervious surface and land surface temperature are the positive correlation, but the correlation coefficient is rather small, which is 0.416456 in 1988, 0.157147/0.158316 in 2001.In the sixth part, it reviews and summarizes mainly this paper, and pointes out the shortage and the question to be pondered further.