长江三角洲城市带扩展对区域温度变化的影响

利用DMSP/OLS夜间灯光数据、土地利用统计数据和气象站常规观测资料,结合NOAA/AVHRR、MODIS反演的月地表温度数据,定量考察了长江三角洲城市群热岛增温效应对区域温度气候趋势的贡献,结果表明:①1992-2003年长江三角洲城市化经历了一个快速的空间扩展过程,宁镇扬、苏锡常、上海大城市区、杭州湾4个城市群构成了一个"之"字形城市带,城市群之间出现城市化连片趋势,城市带区域内1961-2005年年平均气温增温速率为0.28～0.44 ℃/10a,显著高于非城市带区域.②城市热岛效应对区域平均温度的影响以夏秋季最强,春季次之,冬季最弱.③长江三角洲城市带热岛强度和城市总人口对数呈线性正相关关系.④城市带增温效应使得区域的年平均气温在1961-2005年间增加了0.072℃,其中1991-2005年间增温幅度为0.047℃;年最高气温升高了0.162℃,其中1991-2005年间增温幅度为0.083℃,表明1991-2005年间长江三角洲城市带的空间扩展正在改变区域温度变化趋势,且这种增温趋势显著.

Impact of Urbanization on Regional Temper atur e Change in the Yangtze River Delta

Based on non-radiance-calibrated DMSP/OLS nighttime light imagery from 1992 to 2003,urban land area statistical data,meteorological data and land surface temperature data retrieved by MODIS and NOAA/AVHRR data,the influence of urbanization on regional climate trend of temperature in the Yangtze River Delta was analyzed.Conclusions are as follows:(1)There is a significant urbanization process from 1992 to 2003 in the Yangtze River Delta,and the annual mean air temperature increased at a rate of 0.28-0.44 oC/10a in mega city.(2)The urban heat island(UHI)effect on regional mean air temperature in different seasons is summer > autumn > spring > winter.(3)The UHI intensity and the urban total population logarithm are creditable correlated.(4)The UHI effect made the regional annual mean air temperature increased 0.072 oC from 1961 to 2005 and 0.047 oC from 1991 to 2005,and the annual maximum air temperature increased 0.162 oC and 0.083 oC from 1991 to 2005,all indicating that the urban expansion in the Yangtze River Delta from 1991 to 2005 may be regarded as a serious climate signal.