厦门机场秋冬季地面风速突变特征及原因初析

Preliminary Analysis of the Characteristics and Causes of Sudden Ground Wind Speed Changes at Xiamen Airport in Autumn and Winter

摘要: 为提高厦门机场秋冬季飞行安全保障能力，本文基于2019~2024年9月~次年2月厦门机场气象观测及MICAPS数据，统计分析了地面风速突变(2小时内变化≥5 m/s)特征及成因。结果表明：(1) 突变事件年际波动无显著趋势，年均26次，A型(风速骤增)占比67.3%；(2) 月分布呈三峰型(12月主峰、2/9月次峰)，日变化集中于06~09时(峰值07时)；(3) A型突变主导日间(关联海陆风及湍流发展)，B型(风速骤减)偏好夜间(联系辐射冷却及系统衰减)；(4) 成因上，地面高压底前部(44.4%)和500 hPa短波槽(62.7%占比)通过气压梯度增强触发A型突变；冬季强垂直风切变(1月28.3 m/s)及高低空急流耦合(如12月双急流)促进动量下传；强逆温(≥3℃)在冬季(尤其12月)强化A型突变，逆温对湍流发展的阶段性抑制可能加剧风速跃升，弱逆温环境下动力因子作用凸显。本研究为机场风速突变预报提供了物理机制支撑。

Abstract: To enhance the flight safety guarantee capacity of Xiamen Airport during autumn and winter, this paper, based on the meteorological observations and MICAPS data of Xiamen Airport from September 2019 to February 2024, statistically analyzed the characteristics and causes of sudden changes in ground wind speed (changes of ≥5 m/s within 2 hours). The results show that: (1) There is no significant trend in the interannual fluctuations of mutation events, with an average of 26 times per year, and type A (sudden increase in wind speed) accounts for 67.3%; (2) The monthly distribution shows a three-peak pattern (with a main peak in December and secondary peaks in February and September), and the daily variation is concentrated from June to September (with a peak at July). (3) Type A mutations dominate during the day (associated with the development of sea and land winds and turbulence), while type B (sudden drop in wind speed) prefers at night (associated with radiative cooling and system attenuation). (4) In terms of causes, the front part of the ground high-pressure bottom (44.4%) and the 500hPa shortwave trough (62.7%) trigger type A mutations through enhanced pressure gradient. Strong vertical wind shear in winter (28.3 m/s in January) and the coupling of high-altitude jet streams (such as double jet streams in December) promote the downward transfer of momentum. Strong inversion (≥3˚C) intensifies type A mutations in winter, especially in December. The phased inhibition of turbulence development by inversion may exacerbate the rise in wind speed, and the role of dynamic factors becomes more prominent in a weak inversion environment. This study provides physical mechanism support for the prediction of sudden changes in wind speed at airports.