THE IMPACT OF URBANIZATION-INDUCED LAND USE/LAND COVER CHANGES ON NUMERICAL SIMULATION OF AN EXTREME HEAT EVENT IN FUZHOU CITY
-
摘要: 地表种类的城市化对城市区域的热力结构和局地环流都会产生巨大的影响。利用地面、高空观测资料和MODIS地表覆盖资料,使用耦合城市冠层模式(UCM)的区域中尺度数值模式(WRF),对2013年8月8日福州地区的一次极端高温天气过程进行数值模拟,研究地表利用变化对福州城市热岛效应及其对福州城市区域局地环流的影响。结果表明:地表利用的城市化使得午后城市热岛现象更加明显而夜间热岛效应呈现出减小的趋势;地表利用城市化后,中心城区的近地面风速减小,但城区与山区以及城区与海洋之间的局地热力环流明显加强,促进了山谷风和海陆风环流的发展;同时地表加热效应增强,促进了垂直运动的发展。Abstract: Urbanization-induced land use/land cover (LULC) changes have a great influence on the thermal structure and local circulation in urban areas. In this paper, observation data, the MODIS data and the simulated results of the WRF model coupled with the urban canopy model (UCM) are used to investigate the impacts of LULC changes in Fuzhou urban area and discuss the urban heat island effect and the local urban circulation closely related to urbanization-induced LULC changes during an extreme heat event on August 8, 2013 in Fuzhou city. The results show that urbanization-induced LULC changes make the urban heat island effect more obvious in the afternoon, while the nocturnal heat island effect tends to decrease. The near-surface wind gradually reduces after urbanization-induced LULC changes in Fuzhou city. On the contrary, the local thermal circulation between urban area and mountainous area and between urban area and ocean is strengthened obviously, facilitating the development of valley wind, sea wind and land wind circulation. Meanwhile, the surface heating effect of urban area is enhanced, promoting the development of vertical movement.
-
Key words:
- urban heat island /
- land use/land cover /
- MODIS /
- WRF /
- land-sea breeze circulation
-
表 1 数值试验各区域和物理参数化方案
模式参数 D01 D02 D03 D04 分辨率/m 25000 5000 1000 200 格点数(东西) 100 181 271 291 格点数(南北) 104 191 281 291 垂直层数 43 短波辐射 Dudhia 长波辐射 RRTM 微物理过程 WSM6 地面层参数 Eta similarity 陆面过程 Noah 行星边界层 MYJ 长波辐射 Kain-Fritsch None 表 2 数值试验方案
数值试验 C1992 C2005 C2015(CTL) 数据分辨率/km 1.0 1.0 0.5 地表资料时间/年份 1992 2005 2015 表 3 数值模拟结果与实况探空观测的平均绝对误差
时间 2013年8月8日00时 2013年8月8日12时 500 hPa 700 hPa 850 hPa 500 hPa 700 hPa 850 hPa 平均绝对误差 高度/gpm 0.78 0.67 0.53 0.51 0.59 0.56 东西风速/(m/s) 1.66 1.76 1.81 1.67 1.47 1.90 南北风速/(m/s) 1.74 1.78 1.57 1.62 1.73 2.04 表 4 数值试验与观测地面气温的平均值、相关系数和均方根误差 相关系数达到99%置信度水平。
结果评估 区域 观测 C1992 C2005 C2015 平均值 城市 32.83 31.97 32.60 32.59 郊区 30.77 30.34 30.67 31.01 相关系数 城市 0.95 0.95 0.96 郊区 0.96 0.93 0.95 均方根误差 城市 1.76 1.62 1.56 郊区 2.37 2.62 2.34 表 5 数值试验与观测地面风的平均值和均方根误差
结果评估 区域 观测 C1992 C2005 C2015 平均值 城市 1.39 2.18 2.17 1.45 郊区 1.00 2.57 2.27 1.63 均方根误差 城市 1.76 1.71 1.46 郊区 2.29 2.15 1.83 -
[1] OKE T R. The energetic basis of the urban heat island[J]. Quart J Roy Meteor Soc, 1982, 108(455): 1-24. [2] GRIMMOND C S B, OKE T R. Comparison of heat fluxes summertime observations in the suburbs of four North American cities[J]. J Appl Meteor, 1995, 34(4): 873-889. [3] PIELKE R A. Influence of the spatial distribution of vegetation and soils on the prediction of cumulus convective rainfall[J]. Rev Geophys, 2001, 39(2): 151-177. [4] FOY B D, MOLINA L T, MOLINA M J. Satellite-derived land surface parameters for mesoscale modelling of the Mexico City basin[J]. Atmos Chem Phys, 2006, 6(5): 1315-1330. [5] FAN S J, FAN Q, YU W, et al. Atmospheric boundary layer characteristics over the Pearl River Delta, China, during the summer of 2006: Measurement and model results[J]. Atmos Chem Phys, 2011, 11(13): 6297-6310. [6] WAN H C, ZHONG Z, YANG X Q, et al. Impact of city belt in Yangtze River Delta in China on a precipitation process in summer: A case study[J]. Atmos Res, 2013, 125(1): 63-75. [7] CHEN F, KUSAKA H, TEWARI M, et al. Utilizing the coupled WRF/LSM/Urban modeling system with detailed urban classification to simulate the urban heat island phenomena over the Greater Houston area[C]. Vancouver: AMS Fifth Urban Environment Conference, 2004: 23-27. [8] HOLT T, PULLEN J. Urban canopy modeling of the New York City metropolitan area: A comparison and validation of single-and multilayer parameterizations[J]. Mon Wea Rev, 2007, 135(5): 1906-1930. [9] YU M, CARMICHAEL G R, ZHU T, et al. Sensitivity of predicted pollutant levels to urbanization in China[J]. Atmos Environ, 2012, 60(2): 544-554. [10] WANG W G. The influence of thermally-induced mesoscale circulations on turbulence statistics over an idealized urban area under a zero background wind[J]. Bound Layer Meteor, 2009, 131(3): 403-423. [11] 蒙伟光, 郑艳萍, 王宝民, 等.热岛与海风相互作用对珠三角午后强降水影响的观测和模拟研究[J].热带气象学报, 2014, 30(6):1011- 1026. [12] 张赟程, 王晓峰, 张蕾, 等.海风与热岛耦合对上海强对流天气影响的数值模拟[J].高原气象, 2017, 36(3):705-717. [13] 何林宴, 简茂球.广西贵港地区极端高温日的时间变化特征及其环流背景[J].热带气象学报, 2019, 35(5):694-708. [14] 王可心, 陈粲, 包云轩, 等.福建省晋江市城市热岛强度时空变化特征分析[J].热带气象学报, 2019, 35(6):852-864. [15] 张朝林, 苗世光, 李青春, 等.北京精细下垫面信息引入对暴雨模拟的影响[J].地球物理学报, 2007, 50 (5): 1373-1382. [16] MIAO S G, CHEN F, LEMONE M A, et al. An observational and modeling study of characteristics of urban heat island and boundary layer structures in Beijing[J]. J Appl Meteor, 2009, 48(3): 484-501. [17] 何建军, 余晔, 刘娜, 等.复杂地形区陆面资料对WRF模式模拟性能的影响[J].大气科学, 2014, 38 (3): 484-498. [18] 寿亦萱, 张大林.城市热岛效应的研究进展与展望[J].气象学报, 2012, 70(3):338-353. [19] FRIEDL M A, SULLA-MENASHE D, TAN B, et al. MODIS Collection 5 global land cover: Algorithm refinements and characterization of new datasets[J]. Remote Sensing of Environment, 2010, 114(1):168-182. [20] DEE D P, UPPALA S M, SIMMONS A J, et al. The ERA-interim reanalysis: configuration and performance of the data assimilation system [J]. Q J R Meteorol Soc, 2011, 137(656): 553-597. [21] SHIN H H, HONG S Y. Analysis of resolved and parameterized vertical transports in convective boundary layers at gray-zone resolutions [J]. J Atmos Sci, 2013, 70(10): 3248-3261. [22] SHIN H H, HONG S Y. Intercomparison of planetary boundary-layer parametrizations in the WRF model for a single day from CASES-99 [J]. Bound Layer Meteor, 2011, 139(2): 261-281. [23] 黄文彦, 沈新勇, 王卫国, 等.边界层参数化方案对边界层热力和动力结构特征影响的比较[J].地球物理学报, 2014, 57(5): 1399-1414.