Temporal Characteristics and Formation Mechanism Analysis of Surface Gales at Lijiang Airport 

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  • 1. College of Atmospheric SciencesChengdu University of Information TechnologyChengdu 610225SichuanChina
    2. Yunnan Airport Group Co. Ltd. Lijiang AirportLijiang 674100YunnanChina

Online published: 2025-05-20

Abstract

With the rapid development of China's air transportationthe special meteorological conditions of plateau airports have increasingly highlighted the impact on flight safety. In particulargales represent a critical meteorological factor that significantly impact both flight safety and operational efficiency in aviation systems. Utilizing ground observation data of Lijiang Airport from 2021 to 2023along with ERA5 reanalysis datawe con‐ ducted an analysis on the temporal characteristics and formation mechanisms of surface gales at Lijiang Airport. The results show:(1surface gales predominantly occur during the dry seasonwhich spans from January to April each year. These gales tend to be concentrated between 0500UTCthe same as afterand 1100 am on a daily basis. Notablythe peak period for strong winds occurs between 0700 and 0900 amaccounting for 54% of the total number of gales events.2The occurrence of gale events was usually accompanied by a significant change in wind directionespecially around 0300 when the wind direction rapidly shifts from northerly to southerlyand the wind speed increases significantly thereafter. Thereforeairports should be prepared for run‐ way switching before 0300 am to avoid overshooting the tailwind due to sudden changes in wind directionwhich would affect flight safety. During surface galeseven though the positive crosswind speed might not reach the threshold that restricts aircraft takeoff and landingsome extreme eventswhere the positive crosswind speed exceeds 10 m·s-1could still pose a threat to flight safety.3The analysis of physical quantity and circulation background fields revealed that the convergence of variable pressure windsdriven by the afternoon thermal lowsenhanced the vertical convective activity and destroyed the stable laminar knots in the lower atmosphereand then induced the downward transmission of 500 hPa westerly jet momentum to form the surface gale through turbulent mixing. Furthermoreprior to the outbreak of the cold wavethe northern cold vortex accelerated the 500 hPa westerly airflowfurther intensifying the surface gales. By analyzing the thermal and dynamic driving mechanisms of extreme surface galeswe had constructed a conceptual model of surface gales. This model pro‐ vides a theoretical foundation for further enhancing the accuracy of wind warnings and improving flight safety assurance capabilities.4The wind shear characteristics exhibit distinct spatiotemporal patternsduring the phase of decreasing surface wind speedwind shear weakens at 450~550 hPa while strengthening at 550~650 hPa. This variable feature provides an important reference for early warning of wind shear.

Cite this article

ZHAO Yuanfeng, XIAO Tiangui, WEI Xiang, SHI Yiwen . Temporal Characteristics and Formation Mechanism Analysis of Surface Gales at Lijiang Airport [J]. Plateau Meteorology, 0 : 1 . DOI: 10.7522/j.issn.1000-0534.2025.00063

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