太湖湖陆风背景下的苏州城市化对城市热岛特征的影响  

The impact of urbanization on the urban heat island in Suzhou under the influence of Taihu lake-land breeze

作　　者：杨健博[1] 刘红年[1] 费松[2] 张宁[1] 蒋维楣[1] 

机构地区：[1]南京大学大气科学学院,南京210093 [2]江苏省气象局气象探测中心,南京210009

出　　处：《气象科学》2013年第5期473-484,共12页Journal of the Meteorological Sciences

基　　金：国家重点基础研究发展规划(973计划)项目(2010CB428501);公益性行业(气象)科研专项(GYHY201206011);江苏高校优势学科建设工程资助项目

摘　　要：利用南京大学区域边界层模式,选取苏州地区2006年8月12日晴天小风的天气作为背景天气条件进行算例的模拟。分析了该地区在湖陆风环流背景下的城市化进程对热岛特征的影响。结果表明:苏州地区的风场受大尺度系统、湖陆风环流和城市热岛环流系统的共同影响,且湖陆风环流的强度大于热岛环流。苏州地区的城市热岛影响高度可达400 m左右,且在背景风场的影响下,该地区的温度分布会体现出比较明显的下游效应特征,下游效应的距离可达10 km左右。这种下游效应在400 m高度以下比较明显,随高度的升高而逐渐减弱。20 a的城市化进程(1986—2006年)导致苏州城区地表感热通量增加了200 W/m2、潜热通量减少了200 W/m2、湍能增加了0.045 m2/s2、日平均热岛强度增加了0.4℃;热岛环流加强,并使白天混合层最大高度升高了400 m,但对夜间逆温层发展的影响较小。太湖湖陆风,使靠近太湖的苏州市郊的混合层、逆温层高度明显下降,但对距离较远的苏州市区的混合层、逆温层高度影响不大。且太湖的存在对于城市化进程导致的苏州地区热岛强度增加、地表湍流动能增加、感热通量增加、潜热通量减少的趋势有比较明显的缓解作用。To study the impact of urbanization on the urban heat island（UHI） in Suzhou under the circumstance of Taihu lake-land breeze, sunny weather with gentle wind on August 12, 2006 was taken as background synoptic condition, and a series of numerical experiment was conducted with the use of a regional boundary layer model developed by Nanjing University. Results indicated that the wind field over Suzhou area was dominated by the combined influence of large scale system, lake-land and UHI circulation. Additionally, the intensity of lake-land circulation was stronger than that of UHI circulation. The influence of UHI can extend to about 400 m altitude in Suzhou area. Furthermore, under the influence of such wind field configuration, the temperature distribution in this area showed a significant feature ofdownwind effect, whose range was approximately 10 kin. This kind of downwind effect, weakened with the height increased, was obvious at the level below 400 m. With the urbanization process in Suzhou for recent 20 years（ 1986 -2006） , the flux of sensitive heat increased to 200 W/hi2 ; the flux of latent heat to 200 W/m2 ; the turbulent kinetic energy to 0. 045 m2/s2 ; the daily average UHI intensity to 0.4 ℃. The UHI circulation strengthened, and the mixing layer depth during daytime rose to 400 m, but the inversion layer depth changed a little. Moreover, the increase of surface sensitive heat flux, turbulent ki netic energy, UHI intensity and the decrease of latent heat flux resulted from the urbanization were slightly offset by the Taihu Lake effects.

关 键 词：湖陆风 城市热岛 城市化 

分 类 号：P461.8[天文地球—大气科学及气象学]