南阳市大气能见度变化趋势及影响因子分析

Analysis of Variation Trend of Atmospheric Visibility and Its Effect Factor in Nanyang

利用南阳市1995-2005年大气能见度和地面气象要素的观测资料及南阳市环境检测站提供的近3 a空气污染物监测数据,统计分析了近10 a南阳市大气能见度变化特征及其与气象要素和空气污染物的关系,结果表明:南阳市能见度年际变化呈缓慢波动上升趋势,夏秋季节2001年之后呈波动下降趋势;冬季能见度最低,春季最高;能见度月变化呈双峰型,第一个峰值在5月份,第二个峰值在9月份;一日之中,08时能见度最差,14时最好。能见度与同期气象要素及污染物浓度的相关分析表明,能见度与相对湿度、空气污染物PM10浓度呈显著性负相关,与NO2、SO2浓度负相关性较弱,与风速和气压呈弱的正相关,与温度的相关性较为复杂,雾是影响能见度的主要天气现象之一。

Using atmospheric visibility and the meteorological observation data of ground elements in Nanyang from 1995 to 2005 and the air pollutants monitoring data from Nanyang Environmental Monitoring Station of the past three years, change characteristic of atmospheric visibility and the relationship between air pollutants and meteorological elements in the past 10 years in Nanyang were statistical analyzed. The results showed that the interannual change of visibility in Nanyang was slowly upward in volatility. After 2001 was in a downward trend in summer and autumn ; the minimum visibility was in winter and the highest was in spring; visibility on monthly change was bimodal, the first peak was in May, the second peak was in September; in a day, visibility was the worst at 08：00, the best at 14：00. Correlation analysis about visibility with the same period meteorological factors and the pollutant concentration showed that there were significantly negatively correlated between the visibility with relative humidity and PM10 concentration; with NO2, SO2 concentration, the negative correlation was weak; with wind speed and pressure were weakly positive correlation; with temperature, the correlations was more complex; fog is one of the major weather phenomena affected visibility.