Impact Of Urbanization And Land-use Change On The Variations Of Air Temperature In Yangtze River Delta Region

Yangtze River Delta is one of the regions with the highest level of urbanization in China, and study of urbanization and land use change of temperature change has important scientific and practical significance. The data include temperature data of42meteorological stations during1960-2009, NECP/NCAR R1reanalysis surface air temperature monthly data during1979-2009, and urban development statistics during1986-2009in Yangtze River Delta region. Analysis of regional temporal and spatial variation of temperature characteristics; the OMR methods to analyze the impact of urbanization and land-use change on urban air temperature change and contribution rate; analysis relationship between typical urban temperature factors and urban development data, and used principal component method to establishment urban development Composite Index, comparative analysis of different cities and Urban Development Composite Index What are the similarities and differences. The results show that:(1) Annual average temperature, annual mean maximum temperature, annual mean minimum temperature showed an increasing trend, and annual average low temperature increased fastest with annual average high temperature increased slowest. after80years of the20th century warming trend is obvious; The annual average temperature decreased from south to north, but the coastland is slower than the inland. The annual average temperature in Shanghai and Hangzhou bay area increased rapidly, but the southern Zhejiang increased relatively slow.(2)The annual average temperature, annual mean maximum temperature, annual mean minimum temperature OMR trends were0.197℃/10a,0.045℃/10a,0.308℃/10a of the past31years in Yangtze River Delta region. The contribution rates were34.71%,7.94%and50.5%to observed temperature warming. OMR warming trend increased obvious in winter then summer; and the OMR contribution rate is biggest in winter.(3) Annual mean temperature and annual mean minimum temperature characterization OMR variability is proportional to the size of the city, and the annual mean maximum temperature of the large cities OMR value is bigger than metropolis and medium-sized cities. The cubic regression model between urban temperature factors and Urban Development Index is the best.(4) Affect the cities of Shanghai, Hangzhou and Changzhou temperature changes development Indicators mainly urban population, type of land use, energy consumption and urban development efforts level, the common interpretation of the rate of up to91.39%,92.12%and87.6%.