Articles | Volume 17, issue 23
Atmos. Chem. Phys., 17, 14579–14591, 2017

Special issue: Regional transport and transformation of air pollution in...

Atmos. Chem. Phys., 17, 14579–14591, 2017

Research article 07 Dec 2017

Research article | 07 Dec 2017

Impacts of meteorological uncertainties on the haze formation in Beijing–Tianjin–Hebei (BTH) during wintertime: a case study

Naifang Bei1, Jiarui Wu2, Miriam Elser3, Tian Feng2, Junji Cao2, Imad El-Haddad3, Xia Li2, Rujin Huang2, Zhengqiang Li4, Xin Long2, Li Xing2, Shuyu Zhao2, Xuexi Tie2, André S. H. Prévôt3, and Guohui Li2 Naifang Bei et al.
  • 1School of Human Settlements and Civil Engineering, Xi'an Jiaotong University, Xi'an, Shaanxi, China
  • 2Key Lab of Aerosol Chemistry and Physics, SKLLQG, Institute of Earth Environment, Chinese Academy of Sciences, Xi'an, China
  • 3Laboratory of Atmospheric Chemistry, Paul Scherrer Institute, 5232 Villigen, Switzerland
  • 4State Environmental Protection Key Laboratory of Satellite Remote Sensing, Institute of Remote Sensing and Digital Earth, Chinese Academy of Sciences, Beijing, China

Abstract. In the present study, a persistent heavy haze episode from 13 to 20 January 2014 in Beijing–Tianjin–Hebei (BTH) is simulated using the WRF-CHEM model through ensemble simulations to investigate impacts of meteorological uncertainties on the haze formation. Model results show that uncertainties in meteorological conditions substantially influence the aerosol constituent simulations at an observation site in Beijing, and the ratio of the ensemble spread to the ensemble mean (RESM) exceeds 50 %. The ensemble mean generally preforms well in reproducing the fine particles' (PM2.5) temporal variations and spatial distributions against measurements in BTH. The meteorological uncertainties do not alter the PM2.5 distribution pattern in BTH principally or dominate the haze formation and development, but remarkably affect the simulated PM2.5 level, and the RESM for the simulated PM2.5 concentrations can be up to 30 % at the regional scale. In addition, the rather large RESM in PM2.5 simulations at the city scale also causes difficulties in evaluation of the control strategies. Therefore, our results suggest that the ensemble simulation is imperative to take into account the impact of the meteorological uncertainties on the haze prediction.

Final-revised paper