汉中茶区倒春寒时空特征及致灾气象指标研究OA

Based on daily temperature data from March to May from 1965 to 2025 and records of low temperature frost damage to tea gardens from 1995 to 2025 in eight tea-producing counties and districts in Hanzhong City,this study adopted the"Meteorological Indicators for Late Spring Cold"(GB/T 34816-2017)to identify late spring cold processes,and systematically analyzed the spatial distribution,temporal variation,and disaster-causing characteristics of late spring cold in the Hanzhong tea region.On this basis,a disaster-causing meteorological indicator system suitable for the local tea region was constructed.The results show that the average annual occurrence of late spring cold in the Hanzhong tea region from 1995 to 2025 was 0.57 times,with a spatial distribution characterized by high occurrence in shallow mountain and plain areas and low occurrence in mountainous areas.Nanzheng,Mian County,and Chenggu are the main high-occurrence areas.Temporally,it was concentrated in the first half of April,highly coinciding with the budding and leaf expansion period of spring tea.The interannual variation shows significant fluctuations,with high occurrence years in 2000,2006,2011,and 2023.The lowest temperature during the disaster-causing process mainly ranges from 0 to 4℃,accounting for 73％of the total.This article proposed a comprehensive identification index based on three elements:minimum temperature(Tmin),process average temperature anomaly(ΔT),and duration(L).For mild late spring cold,Tmin ranges from 2 to 4℃,ΔTranges from-4 to-2℃,and L≤3 d.For moderate late spring cold,Tmin ranges from 0 to 2℃,ΔTranges from-6 to-4℃,and Lranges from 3 to 6 d.For severe late spring cold,Tmin<0℃,ΔT<-6℃,L>6 d.This index system provided valuable guidance for monitoring and warning,risk identification,disaster prevention and mitigation,and tea garden layout in Hanzhong tea regions.