郑州机场2004-2012年能见度的变化特征

利用郑州机场近9 a（2004-2012年）地面气象观测资料,分析了能见度的年、季节和日变化特征,并统计了低能见度出现的天数。结果表明：郑州机场年平均能见度仅为4 219 m,平均每年上升约69 m,秋季上升速率最快,冬季最慢,出现小于1500 m、800 m和600 m能见度的天数均呈下降趋势;能见度月际变化特征十分明显,春季平均能见度最好,秋季和冬季较差,低能见度出现的天数以秋、冬季较多,春、夏季较少;日变化特征除夏季外,春、秋、冬季能见度都呈现双峰双谷型变化,能见度16时最佳,凌晨4时最差。

Variation Characteristics of Visibility at Zhengzhou Airport During 2004-20 1 2

The interannual,seasonal and diurnal variation of visibility and low visibility days were analyzed based on the observed meteorological data from 2004 to 2012 at Zhengzhou Airport.Results show that the annual average visibility was only 4 219 m,which presented a rising trend with the rate of 69 meters per year,and in fall it increased most and least in winter.The days of visibility less than1 500 m,800 m and 600 m showed a downward trend at the airport.Monthly variation of visibility was very obvious,and the average visibility in spring was best and then in summer,low visibility days appeared more in autumn and winter but less in spring and summer.Diurnal variation of visibility appeared two peak and two valley in spring,autumn and winter,and at 16 ：00 the visibility was best and worst at 04：00.