Diurnal haze variations over the North China plain using measurements from Himawari-8/AHI

Huazhe Shang , Husi Letu , Xiaole Pan , Ziming Wang , Run Ma , Chao Liu , Tie Dai , Shenshen Li , Liangfu Chen , Cheng Chen (1) , Qiaoyun Hu (1)

1 LOA - Laboratoire d’Optique Atmosphérique - UMR 8518

The diurnal variations of haze properties are essential in understanding the haze pollution formation and its environmental impact. Ground-based measurements can provide this information with high temporal resolution, but the haze measurements are not spatially continuous. The Advanced Himawari Imager (AHI) sensor onboard the next-generation geostationary satellite Himawari-8 can provide haze properties with high spatial and temporal resolution. In this study, the diurnal variations of haze frequency, haze properties [aerosol optical depth (AOD), Angstrom exponent (AE) and fine-particle ratio (RF)] and cloud cover are jointly analyzed over the North China Plain (NCP) for summer and winter seasons during 2015-2017. Both the haze and cloud scheme and the haze properties are well validated. The results reveal that the haze frequency in winter (33.51%) is much higher than that in summer (6.34%), and the diurnal variations of AOD values in winter (0.2-0.9) are stronger than those in summer (0.5-0.9). The diurnal maximum haze frequency values in summer (16:00 p.m.) occur 3 h later than the most severe pollution (13:00 p.m.), with AOD values of 0.7-0.9, AE values of 1.1-1.2 and RF values of 0.5-0.6. In winter, the haze frequency increases from 9:00 to 15:00. However, no typical diurnal variations of AOD, AE and RF are shown. It is also found that haze frequency exhibits opposite diurnal variations compared with those of clouds.

Domains: Sciences of the Universe [physics]

Huazhe Shang, Husi Letu, Xiaole Pan, Ziming Wang, Run Ma, et al.. Diurnal haze variations over the North China plain using measurements from Himawari-8/AHI. Atmospheric Environment, 2019, 210, pp.100-109. ⟨10.1016/j.atmosenv.2019.04.036⟩. ⟨insu-03686275⟩