近50年秦岭南北不均匀增温及对城市化响应

根据1961—2012年陕西省均一化气温数据分析了秦岭南北两侧平均气温、最高气温、最低气温的年、季节变化特征，结果表明:秦岭南北两侧年平均气温、最高气温和最低气温均呈增加趋势，增加幅度南北分布不均，北麓温度增幅较南麓显著；气温季节变化存在一定差异，平均气温在春季和冬季增温显著，最高气温在春季增温显著，最低气温在冬季增温显著，秦岭南北两侧春季、秋季气温日较差变大，冬季和夏季气温日较差变小。为了进一步明确气温变化的原因，结合DMSP (defense mete-orological satellite program)/OLS (operational lines-can system) 数据将秦岭南北两侧分为5个区域，分别计算每个区域内城市化对气温变化的影响以及城市化影响的贡献率表明:秦岭北麓城市化过程较秦岭南麓快，城市化发展的差异，导致了城市化对秦岭南北两侧温度影响的不均匀性，秦岭北麓气温变化受城市化影响程度明显高于秦岭南麓，影响主要以平均气温和最低气温为主，城市化发展的差异加剧了秦岭南北两侧气温变化的非均匀性。

Effects of Urbanization on Temperatures over the Qinling Mountains in the Past 50 Years

Based on the normalized temperature datasets of China Meteorological Administration from 1961 to 2012, inter-annual and seasonal varying characteristics of maximum, minimum and mean temperatures over the Qinling Mountains are analyzed.The result shows that average increment of annual average temperature, annual maximum and minimum temperatures in the northern regions are greater than those in southern regions of the Qinling Mountains. The seasonal variation of temperature is different, for average temperature, there is an increase in spring and winter, while the maximum temperature increases obviously in summer, and minimum temperature increases remarkably in winter. There is an obvious increase of diurnal temperature range in spring and autumn while there is a decrease in summer and winter. Mean and maximum temperatures declines remarkably while minimum temperature increasing in summer are the direct cause of summer diurnal temperature range reducing. In order to understand the factor of temperature variation, the DMSP (defense meteorological satellite program)/OLS (operational linescan system) data are used to calculate effects of urbanization and their contributions on air temperature for 5 typical zones. The increase of minimum temperature and average temperature of urban station is found remarkably higher than that of rural station, while the increase of maximum temperature is almost the same. This result shows that effects of urbanization are significant on the increasing of average temperature and minimum temperature. While the variation of maximum temperature is mainly caused by climate change itself. Urbanization development is not at the same pace, the northern part of the Qinling Mountains develops much faster than the southern part. The process of urbanization enhances the warming trend of average and minimum temperature in northern part of the Qinling Mountains, especially in spring and winter. And for the maximum temperature, the process of urbanization weakens the increasing trend in southern part but enhances the warming trend in the northern part. That means the impact of urbanization on temperature may show different characteristics at different climatic zones. The difference of the development of urbanization over the Qinling Mountains enhanced the inhomogeneity of temperature changes.