关键词: 四季划分标准, 气温阈值, 物候频率分布型, 经向风

Abstract: Based on daily temperature data from 61 stations in Liaoning province from 1981 to 2020,referring to national standards (GB/T 42074—2022) and combining with agricultural production characteristics,the temperature indicators for seasonal division in Liaoning province were adjusted using a 5-d moving average method.A new temperature index was proposed,with a 5 d running average temperature >20 ℃ for spring and autumn,≥20 ℃ for summer,and<6 ℃ for winter.Based on national standard and local standard (new temperature index),the four seasons of Liaoning province were divided,and the phenological characteristics of Shenyang,the ecological landscape,and ecological tourism activities were analyzed.The above analysis indicates that using the national standard to divide the four seasons in Liaoning province is not suitable to the local climate,phenology and social activities,and the local temperature index is more suitable for seasonal division than the national standard.Analysis of ERA5 300 hPa meridional wind revealed that the transition time of meridional wind of westerly jet is basically consistent with the seasonal transition time obtained from localtemperature index in Liaoning province.

Key words: Seasonal division standards, Air-temperature thresholds, Phenological phenomena frequency distribution pattern, Meridional wind