Fontes Tânia, Li Peilin, Barros Nelson, Zhao Pengjun
Centre for Urban Planning and Transport Studies, Peking University, Beijing, China; CIAGEB - Global Change, Energy, Environment and Bioengineering Center, University Fernando Pessoa, Porto, Portugal; INESC TEC - INESC Technology and Science and FEUP- Faculty of Engineering, University of Porto, Porto, Portugal.
Centre for Urban Planning and Transport Studies, Peking University, Beijing, China.
J Environ Manage. 2017 Jul 1;196:719-732. doi: 10.1016/j.jenvman.2017.03.074. Epub 2017 Mar 31.
The fast economic growth of China along the last two decades has created a strong impact on the environment. The occurrence of heavy haze pollution days is the most visible effect. Although many researchers have studied such problem, a high number of spatio-temporal limitations in the recent studies were identified. From our best knowledge the long trends of PM concentrations were not fully investigated in China, in particular the year-to-year trends and the seasonal and daily cycles. Therefore, in this work the PM concentrations collected from automatic monitors from five urban sites located in megacities with different climatic zones in China were analysed: Beijing (40°N), Chengdu (31°N), Guangzhou (23°N), Shanghai (31°N) and Shenyang (43°N). For an inter-comparison a meta-analysis was carried out. An evaluation conducted since 1999 demonstrates that PM concentrations have been reduced until 2008, period which match with the occurrence of the Olympic Games. However, a seasonal analysis highlight that such decrease occurs mostly during warmer seasons than cold seasons. During winter PM concentrations are typically 1.3 to 2.7 higher than in summer. The average daily cycle shows that the lowest and highest PM concentrations often occurs in the afternoon and evening hours respectively. Such daily variations are mostly driven by the daily variation of the boundary layer depth and emissions. Although the PM levels have showing signs of improvement, even during the warming season the values are still too high in comparison with the annual environmental standards of China (35 μg m). Moreover, during cold seasons the north regions have values twice higher than this limit. Thus, to fulfil these standards the governmental mitigation measures need to be strongly reinforced in order to optimize the daily living energy consumption, primarily in the north regions of China and during the winter periods.
在过去二十年里，中国经济的快速增长对环境产生了巨大影响。重度雾霾污染天气的出现就是最明显的影响。尽管许多研究人员已经对这类问题进行了研究，但近期研究中仍存在大量时空限制。据我们所知，中国尚未充分研究PM浓度的长期趋势，尤其是逐年趋势以及季节和日周期。因此，在这项工作中，我们分析了从中国不同气候区的五个大城市的自动监测站收集到的PM浓度数据，这些城市分别是北京（北纬40°）、成都（北纬31°）、广州（北纬23°）、上海（北纬31°）和沈阳（北纬43°）。为了进行相互比较，我们进行了荟萃分析。自1999年以来的一项评估表明，直到2008年PM浓度一直在下降，这一时期恰逢奥运会举办。然而，季节性分析表明，这种下降主要发生在温暖季节而非寒冷季节。冬季的PM浓度通常比夏季高1.3至2.7倍。平均日周期表明，PM浓度最低值和最高值通常分别出现在下午和晚上。这种日变化主要受边界层深度和排放的日变化驱动。尽管PM水平已显示出改善迹象，但即使在温暖季节，与中国的年度环境标准（35μg/m）相比，其数值仍然过高。此外，在寒冷季节，北方地区的数值比这个限值高出两倍。因此，为了达到这些标准，需要大力加强政府的减排措施，以优化日常生活能源消耗，主要是在中国北方地区和冬季。
