沙漠与绿洲气象2025，Vol.19Issue(1)：1-12,12.DOI:10.12057/j.issn.1002-0799.2406.20006
乌鲁木齐东南风时空分布及层结稳定度特征分析
Spatial and temporal Distribution and Stratification Stability Characteristics of Southeast Wind in Urumqi
摘要
Abstract
This study analyzes the spatio-temporal distribution of southeast winds under Beaufort scale 3 and 6 wind thresholds,climate change at representative stations,and the stability characteristics of the atmospheric stratification during strong wind events.It also explores the atmospheric circulation responsible for the seasonal variation of southeast winds.The results show that:(1)The Tianshan Grand Canyon is the primary airflow channel for the southeast wind in Urumqi.Two areas with large values extend from the northern end of the Canyon to the northwest and northeast.The wind thresholds are strongest in winter,followed by spring and autumn,and weakest in summer.Large value centers are found at both the north and south ends of the Canyon,with the larger threshold consistently stronger at the north end than the south end throughout the year,except in winter.(2)The inter-monthly distribution characteristics show the highest frequency of southeast winds in winter and the lowest in summer within the Tianshan Grand Canyon.Wind frequency peaks in spring and autumn at the Canyon exit,the main urban area,and the northeast branch,while the highest frequency in the northwest branch occurs in spring,autumn,and winter.The diurnal variation shows a higher incidence in the morning along the northwest and northeast branches,while other areas experience peak occurrences in the afternoon.(3)The inter-annual variation characteristics at representative stations indicate that the annual accumulated wind in Urumqi and Dabancheng has decreased over the past 50 years,with the decline rate in Dabancheng being faster than in Urumqi.From 2000 onward,Urumqi experienced a rapid decline before 2000,followed by a slower decline after 2000,whereas Dabancheng showed the opposite trend.The variation cycles are as follows:Urumqi exhibits 12-year and 5-7 year cycles,with the 12-year cycle being the most prominent,while Dabancheng shows a 6-8 year cycle before 2000.(4)During strong wind events,a stable stratification zone is observed at a height of 1 900 m on the windward slope,and another stable stratification zone is present at 500 m on the leeward slope.At the end of the wind event,the stable stratification height on the windward slope decreases,while the stable stratification height on the leeward slope increases,and wind intensity weakens.(5)Although the frequency of southeast winds is relatively low in the main urban area and the exit of the Canyon,the wind speed is higher than that of other wind directions.The frequency and wind speed of low-level southeast winds in the Tianshan Grand Canyon and Urumqi are stronger in autumn and winter than in other seasons.(6)In spring,the mid-latitude frontal zone is active,leading to a situation of south-high and north-low pressure fields on both sides of the Tianshan Mountains.The resulting significant pressure differences contribute to the high frequency of southeast gales in the urban area.In autumn and winter,the backflow caused by the Mongolian high and the mid-low level anticyclone circulation contribute to the normal low-level southeast wind in the Tianshan Grand Canyon and Urumqi.关键词
乌鲁木齐/东南风/时空分布/层结稳定度/环流归因Key words
Urumqi/southeast wind/spatio-temporal distribution/stratification stability/circulation attribution分类
天文与地球科学引用本文复制引用
汤浩,周雅蔓,李晨,蒋慧敏..乌鲁木齐东南风时空分布及层结稳定度特征分析[J].沙漠与绿洲气象,2025,19(1):1-12,12.基金项目
国家自然科学基金项目(42165002) （42165002）
新疆维吾尔自治区重点基金项目(2024D01D33) （2024D01D33）
