城市非均匀性对城市地表能量平衡和风温特性的影响  

The influence of urban heterogeneity on the surface energy balance and characters of temperature and wind

作　　者：宋玉强[1,2] 刘红年[1] 王学远[1] 张宁[1] 孙鉴泞[1] 

机构地区：[1]南京大学大气科学学院,南京210023 [2]大连市气象台,大连116000

出　　处：《南京大学学报（自然科学版）》2014年第6期810-819,共10页Journal of Nanjing University（Natural Science）

基　　金：国家重点基础研究发展规划(973)项目(2010CB428501;2014CB441203);公益性行业科研专项(GYHY201206011)

摘　　要：为了研究城市的非均匀性对城市气象特征的影响,根据南京市landsat卫星资料的建筑密度分布特征,将南京市不同区域的城市分成:商业型城市、高密度城市、低密度城市.利用天气预报模式(WRF)模式针对南京地区非均匀城市类型分布进行了1年的高分辨率模拟,研究了城市非均匀性对城市地表能量平衡和城市热岛等气象特征的影响.研究结果表明:城市地表能量平衡和城市热岛等气象特征对城市非均匀性比较敏感,城市非均匀性导致平均城市感热、净辐射、热岛强度、城市郊区风速差减弱,而潜热增加.考虑城市的非均匀性之后,地表能量平衡各项以及温度、湿度、风场在城市区域的分布更加复杂,空间分布的方差和极值明显增加.如非均匀城市使平均感热、热岛强度和城市风速衰减分别下降了9.3 W·m-2、0.18℃和0.14m·s-1,潜热增加11.2 W·m-2;但非均匀城市使热岛强度、风速衰减、净辐射的最大值增加了0.28℃、0.28m·s-1和5.7·m-2.城市对于风速的衰减,会导致低空急流带的强度变小、厚度变薄.For the purpose to research the influence of urban heterogeneity on urban meteorological characters,dividing the city into 3 types according the building density data of landset satellite：Commercial,Hi-dens Res（High intensity residential）,Low-dens Res （Low intensity residential）.High resolution numerical simulations for one year were made by using the weather research forcast （WRF）to study the influence of urban heterogeneity on the surface energy balance and characters of temperature and wind.The results showed tha,the urban surface energy balance and urban meteorological characteristic are sensitive about urban heterogeneity.Compared to uniform urban,heterogeneous urban can reduce the average sensible heat,net radiation,urban heat island and the decay of wind speed in urban area,but increase the latent heat.After considering the urban heterogeneity,the surface energy balance,the temperature,the relative humidity,and the wind speed fields exhibit more complex spatial distribution.Variances and extreme values of these meteorological elements in heterogeneity urban are larger than in uniform urban.Compared to uniform urban,the reduction of sensible heat,urban heat island and the decay of wind speed caused by heterogeneous urban are 9.3 W·m-2、0.18 ℃ and 0.14 m·s-1 ,respectively,with the 11.2 W·m-2 increase of latent heat. On the contrary,urban heat island,urban wind speed decay,and net radiation of heterogeneous urban increases by the values of 0.28 ℃,0.28 m·s-1 ,and 5.7·m-2 .In addition,urban can reduce the intensity and thickness of lower-level jet.

关 键 词：城市非均匀性 城市热岛 城市地表能量平衡 

分 类 号：P237[天文地球—摄影测量与遥感]