Some characteristics of ozone concentrations and their relations with meteorological factors in Shanghai

Abstract

Observations of O3NOx, in the winter of 1990 and 1991, the summer of 1991, and the spring of 1993 have been made in Shanghai. We analyze the variations of O3NOx, day by day, the diurnal variations of O3NOx, as well as the relation between O3 and NOx concentrations. Emphasis is put on the variations of O3 with the meteorological factors. We find that correspondent relations, more or less, existed between meteorological factors and O3 concentrations both in maximum and daily average. High O3 concentrations were related to high pressure weather system, low relative humidity, low cloudiness, light wind speed, and fog formation as well. The local circulation on certain situations also affected the ozone concentration. Preliminary statistics of the occurrence frequencies of high ozone concentration days corresponding to some meteorological indexes are given in this paper.