珠江三角洲城市尺度规划对大气环境的影响效应

Impacts of Urban Planning on Atmospheric Environment over the Pearl River Delta Region

为探讨城市尺度规划对局地气象环境的影响,以珠江三角洲不同时期的下垫面为例,选取2001年3月的气象条件,采用数值模拟手段,模拟并分析比较该地区城市群的发展对城市气象环境的影响。结果表明,珠江三角洲城市化发展过程带来热岛强度和范围的扩大,城市区域风速减小,小风面积增大。利用城市尺度规划大气环境评估体系,对广州城市发展规划进行评估,给出影响和优劣比较的定量结果,城市发展对气象环境影响较明显的是城市热岛强度、小风区分布、大气自净能力3个指标,即城市热岛增强,风速减小,大气的自净能力下降。综合评价指数表明在不利天气条件下,城市化过程带来的大气环境影响较大。

The data collected from the Pearl River Delta were used to study the impact of urban planning on local meteorology. The results show that urban heat island became stronger and the influenced area was larger compared with pre-urban situation. Wind speed decreased and light wind speed area increased. The influence of Guangzhou urban planning was assessed based on atmospheric environmental assessment indices. The apparent influencing indices are urban heat island intense, distribution of light wind speed and atmospheric self-clear capability. With urban expansion, urban heat island became stronger, wind speed decreased and atmospheric self-clear capability decreased. The integrated analysis shows that urban expansion has obvious influence on atmospheric environment.