北京两机场四年降雪情况对比及一次典型降雪过程分析
Comparison of Snowfall Situation between Two Airports in Beijing over the Past Four Years and Analysis of a Typical Snowfall Process

本文利用2019年11月~2023年3月大兴机场、首都机场两场的常规地面、高空气象观测资料以及地面自动观测资料，通过数理统计的方法对大兴机场及首都机场四年的降雪情况进行分析并对比，另利用欧洲中心ERA5再分析资料等，对2022年1月20日的典型降雪过程进行天气分析。结果表明：1) 大兴、首都两机场降雪具有明显月际分布特征，主要集中在1月~2月，且以1月份最为明显，没有明显的年变化和日变化特征。2) 由于地理位置、气候特点的差异，首都机场降雪次数明显多于大兴机场。3) 两机场同过程降雪时长没有明显差异，降雪时长主要受系统影响。4) 由于2月降雪次数多且雨雪混合过程比例增多，两机场均2月累积降水量最多，首都机场过程平均降水量略高于大兴机场。5) 1月、2月积雪概率大，积雪深度有明显的月际分布特征，2月积雪深度最大，12月积雪深度最小。6) 首都机场降雪时期较大兴机场更长。
This article uses conventional ground and high-altitude meteorological observation data, as well as automatic ground observation data, from November 2019 to March 2023 at Daxing Airport and Capital Airport to analyze and compare the snowfall situation at Daxing Airport and Capital Airport over the past four years through mathematical statistics, and the typical snowfall process on January 20, 2022 by using the ERA5 reanalysis data of the European Center. The results show that: 1) The snowfall at Daxing and Capital airports has obvious monthly distribution characteristics, mainly concentrated in January to February, and is most obvious in January, without obvious annual or daily changes. 2) Due to differences in geographical location and climate characteristics, the number of snowfalls at Capital Airport is significantly higher than that at Daxing Airport. 3) There is no significant difference in snowfall duration between the two airports during the same process, and the snowfall duration is mainly affected by the system. 4) Due to the frequent snowfall in February and the increasing proportion of mixed rain and snow processes, both airports have the highest cumulative precipitation in February, with the average precipitation during the process at Capital Airport slightly higher than that at Daxing Airport. 5) The probability of snow cover in January and February is high, and the depth of snow cover has obvious inter month distribution characteristics. The depth of snow cover in February is the highest, and the depth of snow cover in December is the smallest. 6) The snowfall period at Capital Airport is longer than that at Daxing Airport.