1961—2014年济南市雾日数变化特征分析

Variation Characteristics of Fog Days in Jinan from 1961 to 2014

为了提高雾预测预报水平,利用济南市区国家级地面气象观测站1961—2014年的逐日观测资料,采用线性倾向估计方法拟合雾日数的变化趋势对其进行分析,并使用设定的雾日数异常评价标准对雾日数异常情况进行评价。结果显示:1961—2014年济南雾日数年际变化和四季变化均呈变少的趋势,济南雾日数变化线性倾向率为-1.362 d/10 a;年平均雾日数为16天;年最少雾日数5天,分别出现在1969年、2008年和2010年;最多雾日数39天,出现在1964年;显著偏少年数为1年,偏少年数为5年,正常年数为41年,偏多年数为2年,显著偏多年数为2年,异常偏多年数为3年。秋季变化线性倾向率为-0.444 d/10 a,在雾日数四季变化中最为明显;济南雾日数冬季变化线性倾向率为-0.211 d/10 a,在雾日数四季变化中最为缓慢。济南春季平均雾日数为1.5天,冬季平均雾日数为6.5天;在四季平均雾日数中,春季是最少的季节,冬季是最多的季节。济南春季雾日数正常年数为50年,是异常年份最少的季节;济南秋季雾日数正常年数为34年,是异常年份最多的季节。

The paper aims to improve the forecast level of fog. Based on the daily observation data from Jinan National Surface Meteorological Observation Station during 1961-2014, the authors analyzed the variation trend of fog days by using the linear trend estimation method and assessed the abnormal conditions of fog days by using the anomaly evaluation criterion. The results showed that： there were decreasing trends for both annual and seasonal variation from 1961 to 2014 with a linear tendency rate of-1.362 d/10 a; the annual average fog days was 16 days, the minimum value was 5 days appeared in 1969, 2008 and 2010, and the maximum value was 39 days in 1964; there was 1 year which was significantly less than others, there were 5 years which were less than others, there were 41 years which were normal; there were 2 years which were more than others, there were 2 years which were significantly more than others, there were 3 years which were obviously more than others; for the seasonal variation linear tendency rate, the peak value was -0.444 d/10 a in autumn, and the lowest value was -0.211 d/10 a in winter. It was 1.5 and 6.5 days for the mean seasonal fog days in spring and winter, respectively, which were the minimum and maximum date in the four seasons; the number of normal years was 50 for the fog days in spring, and spring was the season with the least number of abnormal years; while it was 34 for the number of normal years in winter, and winter was the season with the biggest number of abnormal years.