贵州省能见度自动观测与人工观测低能见度特征对比分析

Comparative Analysis of Automatic and Manual Observed Low-Visibility Characteristics in Guizhou

摘要: 为考察能见度自动监测前后低能见度在贵州时空分布的新特征、对交通的影响等，本文选取2008~2022年贵州84个气象站能见度观测资料，进行了分观测时段、分低能见度等级、分影响天气类型的分析和比较。发现自动观测提高了观测频次和观测精度，但出现了气候突变，抽取与人工观测相同时次的观测数据可提高跨越自动观测前后的低能见度分析资料的连续性。定时观测能见度数据发现，自动观测后，贵州各站的站点雾日变化较大，多雾中心更强、更多；各时次自动观测前后年均低能见度变化不一致，占比最多的8时低能见度差异最大。进一步分析区域雾日，发现自动观测后年均区域雾日增加了22.4 d，按照天气影响系统划分的锋面雾日显著增加，而辐射雾日减少；对区域雾日计算能见度系数计算，发现自动观测后低能见度强度增加，对交通影响增加，其中锋面雾日的影响大于辐射雾日；两类雾日中3级低能见度站次都有所增加，说明自动观测更易捕捉到能见度低的天气。总之，分类雾在能见度自动观测中呈现出的新特点值得进步一深入研究。

Abstract: In this paper, in order to investigate the new characteristics of low visibility in spatial and temporal distribution and its impact on traffic before and after the automatic visibility observation in Guizhou, a comparative analysis of visibility observation data from 84 meteorological stations in Guizhou from 2008 to 2022 is carried out in terms of observation period, low-visibility level, and influence weather type. It was found that automatic observation improved the observation frequency and accuracy, but there was a sudden change in climate. Extracting the observation data at the same time as manual observation can improve the continuity of low-visibility analysis data across automatic observation. The visibility data of periodic observation show that after automatic observation, the fog days of each station in Guizhou have great changes, and the foggy centers are stronger and more; change of annual low visibility before and after automatic observation is inconsistent, and the difference of low visibility at 8 hours is the largest. Further analysis of regional fog days shows that the annual average regional fog days increased by 22.4 d after automatic observation, with a significant increase in the frontal type days and a decrease in the radiation type days according to weather influence system; the visibility coefficient of regional fog days is calculated, and it is found that the intensity of low visibility increases and the impact on traffic increases after automatic observation, and the impact of frontal fog days is greater than that of radiation fog days; the number of level 3 low-visibility stations in both types of fog days has increased, indicating that low-visibility weather would be more easily captured by the automatic observation. In short, the new characteristics of classification fog in automatic visibility observation are worth further study.