An analysis on the effects of urbanization on the local climate of three inland developing cites in East China

Abstract

Most studies on the impact of China’s urbanization on local climate focus on developed coastal cities, with little attention paid to inland developing cities. In the present study, we selected three representative and neighboring developing cities (Nanchang, Jiujiang and De’an) in East China to examine, through comparative analyses, local climate changes in inland developing cities with varying sizes during the past 45 years, based on homogenized datasets (1967-2012) released by the National Ground Meteorological Station, taking local economic, demographic, etc. factors into account. Our findings are as follows: The speed of urbanization in these three inland developing cities is correlated to their respective status and sizes - the bigger the city, the faster the urbanization occurring in said city. The pace of the urbanization has a clear impact on the local temperature variability. For the past 45 years, the warming rate in Nanchang (large city) was approximately 0.27 /decade while that in Jiujiang (middle-size city) was approximately  0.23 /decade and that in De’an (small town) was approximately 0.20 /decade. The warming rate was observed to rise in line with city size. The number of high temperature days (HTDs) increased significantly in all three cities over the course of the past 45 years. During the period of 2003 to 2012, HTDs in Nanchang, Jiujiang and De’an increased by 9.8, 5.1 and 1.3 days, respectively, compared with the period of 1967-1976. The larger the city, the more significant the increase in HTDs was observed.