贵阳市臭氧夜间高值现象的初步分析

A preliminary analysis on the high value of ozone at night in Guiyang City

根据贵阳市近地面臭氧浓度及相关气象因子的观测资料,重点分析了城市臭氧夜间浓度高值典型日的时空分布规律、对应典型日的天气系统以及相关气象因子的变化情况。结果表明,臭氧夜间浓度高值典型日臭氧高值站点具有主城中心区域出现频率低,城郊地区靠近高压输变电设施站点出现频率高的空间分布特征;臭氧夜间高值典型日的臭氧浓度日变化呈"双峰型",最高小时质量浓度出现在凌晨5时左右;夜间臭氧高浓度易出现在锋面天气系统中,占全部个例的73.2%,多为相对湿度较高、气温相对较低且风速较大的天气条件下。

Based on the observation data of near - surface ozone concentration and related meteoro-logical factors in Guiyang City, the article focuses on the analysis of temporal and spatial distribution regularities of typical nighttime high ozone concentrations vs the corresponding weather conditions and the variation of the related meteorological factors during those typical days. The results show that the spatial distribution of typical days with nighttime high ozone concentration may be characterized by the fact that their frequency of occurrence was found to be lower in downtown Guiyang than that in the suburb area where high - voltage power transmission facilities are located. The daily variation of o-zone concentration during typical days with nighttime high ozone concentrations shows an typical ＂ bi-modal＂ pattern, where the highest hourly mass concentration was found at around 5 am; nighttime high ozone concentration was likely to appear in the frontal weather system, accounting for 73. 2% of the total cases, mostly being under relatively high humidity, low temperature and high wind speed conditions.