2018~2022年淮河航道强风的时空特征及聚类分析

Studies on Temporal and Spatial Characteristics and Cluster Analysis of Strong Winds in Huai River Channel from 2018 to 2022

强风,特别是区域性强风天气严重影响淮河通航安全,因此研究淮河航道强风的时空分布特征及其变化规律,分析区域性强风发生的天气环流背景十分重要,可以为及时发布预报预警、做好气象防灾减灾工作提供重要参考。利用安徽省气象信息中心提供的2018~2022年淮河航道93个气象站的小时观测资料,结合业务规定和预警需求,筛选出5a来淮河航道出现的所有强风事件,分析淮河航道强风的时空变化特征及其对航运安全的影响,并对区域性强风天气过程的环流背景进行分类。结果显示:淮河航道强风年平均日数33 d,年强风日数最多为103 d,最少为5 d;淮河航道强风年平均小时数110 h,年小时数最多为524 h,最少为10 h;淮河航道日强风风险概率大部分在20%以下,有78.5%的站点日强风风险概率在5%~15%之间,最大值为28%,最小值为1%。结果表明:淮河航道强风次数的时间变化整体趋势较为一致,春、冬季多,秋季最少,3月最多,9月最少,夜间多,白天少,峰值一般出现早晨;淮河航道每月都有影响航运安全的强风发生,强风以瞬时风为主,风速的极大值多出现在夏季;淮河航道北岸、下游出现强风的概率较大,风向以偏北风为主,其中大多是偏北横向风;淮南港与蚌埠港之间强风盛行风向存在东、西方向的突变,3月和7月是港口发生强风的高峰期;淮河航道区域性强风过程主要由强冷空气和强盛偏南季风引起的,分为东北冷涡型(Ⅰ)、西南强风型(Ⅱ)、冷空气大风型(Ⅲ) 3类。

Strong winds, particularly those of regional nature, have serious influence on Huai River navigation safety. Therefore, it is very important to study the temporal and spatial distribution of strong winds in the Huai River channel and analyze the synoptic situation of regional strong winds. The study provides important reference for issuing forecast and warning in time, likewise for prevention and mitigation of meteorological disaster. In this paper, based on the hourly wind observation data including 93 stations in the Huai River channel provided by Anhui Meteorological Information Center from 2018 to 2022, combining with business rules and early warning requirements, all strong wind events occurred in the Huai River channel in past 5 years have been screened out, the temporal and spatial variation characteristics of strong winds in the Huai River channel and its influence on ship-ping safety have been analyzed, the circulation background of regional strong wind weather process has been classified. The analysis shows that the average year of strong wind days in the Huai River channel is 33 days, with a maximum of 103 days and a minimum of 5 days. Average year of strong wind hours in Huai River channel is 110 h, with a maximum of 524 hours and a minimum of 10 hours. The risk probability of daily strong wind in the Huai River channel is mostly below 20%, primarily between 5% and 15% in 78.5 percent stations, the maximum probability is 28% and the minimum probability is 1%. The results show that the general trend of strong wind frequency for the time variation in the Huai River channel is consistent, which is more in spring and winter than in autumn, the most in March, the least in September, more at night and less during the day, and the peak value usually occurs in morning. The strong winds that affect shipping safety in the Huai River Waterway keep happening every month. The majority of strong wind is instantaneous wind, and extreme wind speed often appears in summer. The strong wind appears in the north bank and lower reaches of Huai River channel with more probability. The strong wind is usually in a northern direction, which is mainly attributed to northerly crosswind. The strong wind prevails between Huainan and Bengbu ports, which has a sudden change in the East-west direction. The peak period of strong winds arise in March and July at the ports. The regional strong wind in Huai River channel mainly because of strong cold air and southerly monsoon, which can be divided into three types: northeast cold vortex type (Ⅰ), southwest strong wind type (Ⅱ) and cold air strong wind type (Ⅲ).