Study on a Large-Scale Persistent Strong Dense Fog Event in Central and Eastern China

Abstract

A large-scale persistent strong dense fog (SDF) event that occurred from December 30, 2016, to January 5, 2017, in central and eastern China is analyzed by using a variety of data, including high-resolution satellite and surface observations, meteorological tower observations, fine-resolution sounding observations, and NCEP/NCAR reanalysis data. The results show the following: (1) The SDF event has the characteristics of long duration, wide influence range, large intensity, and serious air pollution. During the study period, there are 531 stations with SDF events, covering an area of over 360,000 km2. There were five stations in Hebei province where the fog lasted for more than 77 hours, and even some stations did not dissipate during the day. (2) Radiation fog and advection fog alternate in this SDF event, namely, radiation fog (20:00 BT on December 30 to 14:00 on January 1), advection radiation fog (20:00 on January 1 to 08:00 on January 2), radiation fog (night on January 2 to daytime on January 3), and advection radiation fog (night on January 3 to January 5). The characteristic of radiation fog is that the central and eastern part of China was controlled by “L” type high pressure. In the stage of advection radiation fog, the combined effect of weak cold advection and radiation cooling leads to the occurrence of SDF. (3) Regarding the duration of the fog event, the inversion structure is continuously maintained at night and in the morning near the stratum, and when the fog intensity is strong, the inversion intensity is correspondingly large, the fog top is lower than the inversion layer top, and the top of the SDF is between 80 and 400 meters.

Estimating Hourly Surface Shortwave Radiation over the Tibetan Plateau by Assimilating Himawari-8 Cloud Optical Thickness

“…The vigorous and rapid cloud convective activities and intense solar radiation over the Tibetan Plateau have challenged the accurate estimation of cloud and surface shortwave radiation (SSR) (Hu et al, 2019;Tang et al, 2019;Wang et al, 2020). The accurate simulation of clouds is di cult using numerical weather models, but they directly affect SSR, especially in summer (Li et al, 2019;Tang et al, 2020;Tsyrulnikov et al, 2003;Yang et al, 2020).…”

A Movable Fog-Haze Boundary Layer Conceptual Model Over Jianghuai Area, China

“…East China is a region with frequent fog and haze (Chen et al, 2021;Wang et al, 2020;Zhang et al, 2018;Zong et al, 2020). Local emissions, pollutants transported from the North China Plain, and boundary layer change can all affect the intensity and duration of the fog-haze episode (Liang et al, 2017;Wang et al, 2016;Yu et al, 2016).…”