Simulation and analysis of a winter advection fog in Beijing Area;

The micro-meteorological elements of an advection fog, which occurred in Feb.

The physical mechanism and boundary layer structures of the advection fog are studied thoroughly,and the results are as follows.

It is found in practice that the probability increases for the appearance of sea advection fog in dusk or the next day when radar has detected the existence of evaporation duct, This article is for purpose to explain the relationship between evaporation duct and advection fog and provides a new way to forecast sea advection fog from evaporation duct.

It is found in practice that the probability increases for the appearance of sea advection fog in dusk or the next day where radar has detected the existence of evaporation duct, This article is for purpose to explain the relationship between evaporation duct and advection fog and provide a new way to forecast sea advection fog from evaporation duct.

It is an advection-radiation fog.

So almost all available observational data are used to analyze the evolutionary process of the fog from it’s formation to dissipation, and it’s concluded that it’s a typical advection-radiation fog occurred over the sea-land interface in winter.

Based on the chemical analyses of the fogwater samples,the chemical characteristics and differences in the ion composition of fogwater between radiation and advection-radiation fog episodes are studied.