次网格非均匀性对区域气象环境模拟的影响研究——以长三角城市群为例  

The influence of sub-grid heterogeneity on regional meteorological environment simulation:A case of the Yangtze River Delta urban agglomeration

作　　者：束梓建 马红云[1,2] 张弥 刘勇洪 吉蒙 徐永明 SHU ZiJian;MA HongYun;ZHANG Mi;LIU YongHong;JI Meng;XU YongMing(Key Laboratory of Meteorological Disaster,Ministry of Education(KLME)/Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters(CIC-FEMD)/Joint International Research Laboratory of Climate and Environmental Change(ILCEC),Nanjing University of Information Science and Technology,Nanjing 210044,China;School of Atmospheric Sciences,Nanjing University of Information Science and Technology,Nanjing 210044,China;School of Atmospheric Sciences,Nanjing University,Nanjing 210023,China;CMA Earth System Modeling and Prediction Centre,Beijing 100081,China;School of Remote Sensing&Geomatics Engineering,Nanjing University of Information Science and Technology,Nanjing 210044,China)

机构地区：[1]南京信息工程大学气象灾害预报预警与评估协同创新中心/气象灾害教育部重点实验室,南京210044 [2]南京信息工程大学大气科学学院,南京210044 [3]南京大学大气科学学院,南京210023 [4]中国气象局地球系统数值预报中心,北京100081 [5]南京信息工程大学遥感与测绘工程学院,南京210044

出　　处：《地球物理学报》2024年第8期2909-2925,共17页Chinese Journal of Geophysics

基　　金：国家自然科学基金面上项目(42175032,42271351)资助。

摘　　要：长三角地区是我国城镇化程度最高的地区之一,下垫面存在典型的非均匀性特征,复杂下垫面结构甚至体现在亚公里级尺度.为了探讨城镇化背景下土地利用精细化对气象环境的影响,本文利用高分辨率土地利用数据探讨了次网格非均匀性对长三角地区气象环境模拟的影响.在基于WRF(Weather Research and Forecasting model)模式对2020和2022年夏季的数值模拟过程中,分别采用Noah_mosaic/Noah陆面方案开展是否考虑次网格非均匀性的高分辨率敏感性试验.结果表明,相比Noah方案,Noah_mosaic方案模拟结果与观测的相关性更高,误差更小,说明其能更好地反映城市群区域复杂下垫面物理过程.考虑次网格非均匀性后,城区变冷变湿,郊区变暖变干,这种变化在夜间更为显著,尤其是温度场,白天城区/郊区平均温度变化为-0.04℃/0.05℃,夜间城区/郊区平均温度变化为-0.14℃/0.53℃.非均匀性对模拟结果的影响可达到400 m高空,特别是在夜间增加了郊区大气的不稳定性.同时,夜间几乎整个陆地区域内的体感温度增加约0.27℃.此外,研究还发现当格点中建筑占比小于50%时,除了日最低温T_(min)以外,气象要素随着建筑占比的增加变化幅度较大,T_(mean)和T_(max)增率分别达到0.29℃/10%和0.55℃/10%,反之,则T_(mean)和T_(max)增率仅为0.1℃/10%和0.06℃/10%,这说明低建筑密度区域的小城镇未来发展将对气象环境产生更大的影响.The Yangtze River Delta(YRD)region is one of China's most urbanized areas,which has typical non-uniformity features of the underlying surface and complicated underlying surface structures that even manifest at the sub-kilometer scale.This research investigates the influence of subgrid nonuniformity on the simulation of the meteorological environment in the YRD region utilizing high-resolution land use data.The Noah_mosaic/Noah land surface scheme is used to perform a high-resolution sensitivity test with or without taking subgrid nonuniformity into account during the numerical simulation of summer 2020 and 2022 based on the WRF(Weather Research and Forecasting model)model,respectively.Results demonstrate that,in contrast to the Noah scheme,the Noah_mosaic scheme's simulation results have a stronger correlation with observations and a smaller inaccuracy,suggesting that it is more capable of accurately representing the intricate physical processes that occur beneath the surface of the urban agglomeration region.The suburban area becomes warmer and drier and the urban area gets colder and wetter after taking into account the subgrid nonuniformity.This difference is more pronounced at night,particularly in the temperature field,where the average temperature change is -0.14℃/0.53℃ during the night and -0.04℃/0.05℃during the day in the urban/suburban area.Non-uniformity in simulation results can reach up to 400 m altitude,resulting in an increase in instability in the suburban atmosphere,particularly at night.At the same time,the body temperature rises by approximately 0.27℃ in almost all areas of land at night.In addition,it is found that when the proportion of buildings in the grid is less than 50%,except the daily minimum temperature Tmin,the meteorological elements change greatly with the increase of the proportion of buildings,and the growth rates of Tmean and Tmax reach 0.29℃/10% and 0.55℃/10% respectively,whereas the growth rates of Tmean and Tmax are only 0.1℃/10% and 0.06℃/10%,which suggests

关 键 词：次网格 非均匀性 数值模拟 气象环境 

分 类 号：P401[天文地球—大气物理学与大气环境]