• 关键词：PM_2.5  北京  红色预警  重污染

• 基金项目：国家科技支撑计划（No.2016YFC0208902）；河南省高校科技创新团队支持计划项目（No.16IRTSTHN012）

• 李涛
• 河南大学环境与规划学院, 开封 475004

• 程兵芬
• 2. 北京师范大学水科学研究院, 北京 100875;3. 中国环境科学研究院, 北京 100012

• 陈云波
• 中国环境科学研究院, 北京 100012

• 高尚银
• 北京清控人居环境研究院, 北京 100083

• 谢晓明
• 2. 北京师范大学水科学研究院, 北京 100875;3. 中国环境科学研究院, 北京 100012

• 党鸿雁
• 中国环境科学研究院, 北京 100012

• 王继康
• 国家气象中心, 北京 100081

• 张凯
• 中国环境科学研究院, 北京 100012

• 摘要：综合利用监测数据并结合数值模型，分析了2015年北京市第2次空气重污染红色预警期间PM_2.5浓度变化特征并初步评估了减排措施对PM_2.5浓度的影响.结果表明：污染初期北京市南部地区PM_2.5浓度明显偏高，且PM_2.5极端高值往往出现在北京南部站点.污染输送阶段，北京市PM_2.5小时浓度在短时内呈爆发式增长，浓度积累速率可达5~10 μg·m^-3·h^-1.污染缓解阶段，偏北风作用，空气质量转好.预警期间北京市空气质量南北差异较大.应急措施实施后，北京市PM_2.5环境浓度下降约20%~25%. PM_2.5累积速率呈现出交通站>城区站>背景站的特征，与重污染日平均值相比交通站下降幅度最大，表明减排措施在交通站更加显著.气象条件对重污染的形成和结束起着决定性作用，为了更好的做好空气质量预警预报工作，应加强对小尺度天气系统的研究，同时关注不同方位PM_2.5浓度峰值及重污染持续时间的变化，形成北京市分区预报预警的经验.

• Abstract：Variations of PM_2.5 concentrations and effects of pollution control measures during the second red alert for air pollution in 2015 in Beijing were analyzed based on atmospheric pollutant monitoring data and numerical simulations. Results showed that in the early period of the red alert, PM_2.5 concentrations were significantly higher with the highest record in the southern area of Beijing. In the air pollution transport phase, PM_2.5 concentrations appeared to be in an explosive growth and the PM_2.5 accumulation rate could reach up to 5~10 μg·m^-3·h^-1. In the alleviated pollution stage, the PM_2.5 concentrations significantly decreased due to northerly winds. The PM_2.5 concentrations decreased by 20%~25% after the implementation of emergency response measures. The accumulation speed of PM_2.5 was the highest at traffic sites and lowest at background sites. The accumulation speed of PM_2.5 decreased significantly at traffic sites compared to their average values from all heavily polluted days due to even and odd-numbered license plate restriction on motor vehicles. Regional weather conditions played a critical role in the formation of air pollution. In order to improve air quality forecasting and early warnings, we should strengthen investigation of small-scale weather systems and pay attention to the changes of PM_2.5 peaks and duration of heavy air pollution in different directions, thereby accumulating experiences in air quality forecasting and early warning in different districts of Beijing.

• Key words：PM_2.5  Beijing  red alert  heavy air pollution

• 
  摘要点击次数： 1119 全文下载次数： 1412