Analysis of Four Meteorological Factors Affecting Aviation Safety in Yunnan

In order to investigate the four key meteorological factors affecting aviation safety and their regional variations in Yunnan， research employed daily and hourly ground observation data from 125 meteorological stations across Yunnan from 2010 to 2021， as well as airport ground observation data from Tengchong Tuofeng Airport during 2013 -2019.Initially， an analysis was conducted on the primary seasonal variations of key meteorological elements in Yunnan.Subsequently， a spatiotemporal evolution analysis was performed for short-duration heavy precipitation and strong wind events during typical seasons at 15 airports.Furthermore， select observational data from typical plateau mountain airports-Tengchong Tuofeng Airport， and compare it with observation data from the Tengchong meteorological station.Analyze the annual frequency of short-duration heavy precipitation events during summer and the daily occurrence periods of spring strong wind events.Ultimately， a complex interrelation analysis among the four categories of meteorological elements was undertaken， followed by an exploration of the spatial distribution patterns of safe and dangerous aviation days in the Yunnan region.The findings revealed the following outcomes： （1） Short-duration heavy precipitation was most pronounced during summer， with areas spanning from Baoshan through Lincang to Puer experiencing heightened occurrences.Spring was characterized by prominent strong wind occurrences， particularly in Ninglang and Kunming， both exhibiting an increasing trend in the frequency of windy days.Notably significant was the occurrence of low visibility during autumn， predominantly observed in the southwestern region of Yunnan， encompassing Lincang， Cangyuan， Puer， and Xishuangbanna， with an escalating tendency.The spatial distribution of low clouds remained relatively similar across all seasons， with higher occurrence frequencies and distribution areas noted during summer and autumn， as opposed to winter and spring.（2） The occurrence of short-duration heavy precipitation events in summer exhibited a distinct positive correlation with precipitation amount， and the timing of occurrences aligned well with the primary operational periods of the airports.Variances in springtime strong wind events were noticeable among airports， predominantly transpiring between 14:00 and 23:00 （Beijing time）.（3） The localized nature of weather systems results in frequency disparities in weather phenomena occurring at airport locations compared to their surrounding areas， while maintaining a correlation in their patterns of variability.（4） Notably elevated were the average numbers of safe aviation days in the northern region along the Dali-Kunming alignment， compared to the southern areas of Yunnan.The majority of Yunnan's locales exhibited a declining trend in safe aviation days， whereas dangerous days were concentrated along the eastern vicinity of Puer to the western border of Wenshan， presenting an increasing trend along the Diqing-Lijiang-Kunming westward direction.