Impacts of mountains on black carbon aerosol under different synoptic meteorology conditions in the Guanzhong region, China
Impacts of mountains on black carbon aerosol under different synoptic meteorology conditions in the Guanzhong region, China
复制标题
关中地区不同天气气象条件下山体对黑碳气溶胶的影响
DOI：
10.1016/j.atmosres.2015.05.016
复制
发表时间：
2015
影响因子：
5.5
通讯作者：
Zhang Qiang
中科院分区：
文献类型：
--
作者：
Zhao Shuyu;Tie Xuexi;Cao Junji;Zhang Qiang
针对西安市及其周边地区（关中-广州地区）近年来冬季空气污染严重的问题，利用现场黑碳（BC）观测和区域动力化学模式（WRF-Chem模式）对2013年1月3日至13日发生的一次灰霾天气过程进行了研究。结果表明，测得的BC浓度表现出很大的日常变化。研究了天气系统、局地气象参数和地形效应对BC变率的影响。由于广州地区北为黄土高原，南为秦岭山脉，特别是海拔3000 m以上的秦岭山脉，因此本文重点分析了秦岭山脉对BC污染的影响。分析表明，西安市和广州地区的BC污染受天气系统、局地气象风场和秦岭山脉的强烈影响。在典型的东北风条件下，风被秦岭阻挡，BC颗粒被困在山脚下，导致西安市的BC浓度很高。在典型的东风条件下，BC粒子沿沿着和秦岭山麓输送。在这种情况下，山河谷起到了加速东风的作用，从而减少了BC污染。在典型的静风条件下，BC粒子从其源区扩散较少，且从秦岭到西安市有山风，BC粒子在城市中积累，特别是在城市的北侧。研究结果表明，在地处复杂地形条件的广州地区，山区对灰霾的形成起着重要作用。
The Xi'an City and the surrounding area (the Guan-Zhong—GZ region) in western China have been suffering severe air pollutions during wintertime in recent years.In-situblack carbon (BC) measurement combined with a regional dynamical and chemical model (WRF-Chem model) is used to investigate the formation of a haze episode occurred from Jan. 3rd to Jan. 13th 2013. The results show that the measured BC concentrations exhibit a large day-to-day variability. The impacts of synoptic weather systems, local meteorological parameters and mountain effect on the BC variability are studied. Because the GZ region is surrounded by two major mountains, the Loess Plateau in the north and the Qinling Mountains in the south, especially the peak of the Qinling Mountains higher than 3000 m, we particularly analyze the effects of the Qinling Mountains on the BC pollution. The analysis shows that the BC pollution in Xi'an City and the GZ region is strongly affected by the synoptic weather systems, local meteorological winds and the Qinling Mountains. Under a typical northeast wind condition, winds are blocked by the Qinling Mountains, and BC particles are trapped at the foothill of the mountains, resulting in high BC concentrations in the city of Xi'an. Under a typical east wind condition, BC particles are transported along a river valley and the foothill of the Qinling Mountains. In this case, the mountain-river valley plays a role to accelerate the east wind, resulting in a reduction of the BC pollution. Under a typical calm wind condition, the BC particles are less diffused from their source region, and there is a mountain breeze from the Qinling Mountains to the city of Xi'an, and BC particles accumulate in the city, especially in the north side of the city. This study illustrates that while locating between complicated terrain conditions, such as the GZ region, the mountains play very important roles for the formation of hazes in the region.