遂宁市倒春寒时空演变特征分析

Analysis of Spatiotemporal Evolution Characteristics of Late Spring Coldness in Suining

利用1960—2022年遂宁市3个国家基本气象站逐日气象资料,依据《倒春寒气象指标》(GB/T34816-2017),通过统计遂宁市倒春寒个例并计算其气象指标k值,对近60 a遂宁市倒春寒的时空演变、成因及影响进行分析。结果表明:1960—2022年遂宁市几乎每年3—5月都有倒春寒发生,多为轻度倒春寒;倒春寒气象指标k值在空间上整体呈西高东低的分布特征,在时间上存在30~35 a、12~15 a及8~10 a共3种不同尺度的周期变化;贝加尔湖附近强冷空气东移南下,其底部冷平流结合高原槽或南支槽共同影响遂宁市,产生剧烈降温,导致重度倒春寒气象灾害发生;当春季出现超过4℃以上的降温且后期温度回升缓慢时,需重点关注倒春寒气象灾害对农业的影响。

Based on the daily meteorological data of 3 national basic weather stations in Suining from 1960 to 2022,according to the“Meteorological Index of Late Spring Coldness”(GB/T34816-2017),the spatial and temporal evolution,causes and effects of late spring coldness in Suining City in the past 60 years were analyzed by counting the cases of late spring coldness in Suining City and calculating the meteorological index k value.The results showed that from 1960 to 2022,the late spring coldness occurred almost every March to May in Suining City,mostly mild late spring coldness.In Suining,the overall distribution of meteorological index k value was high in the west and low in the east.From the perspective of wavelet analysis,the meteorological index k value had three different scale periodic changes of 30~35a,12~15a and 8~10a.The strong cold air near Lake Baikal moved eastward and southward,and its cold advection at the bottom combined with the plateau trough or the south trough jointly affected Suining,resulting in severe late spring coldness weather disaster.When the temperature drops more than 4℃in spring,and the temperature rises slowly in the later period,it is necessary to pay more attention to the impact of cold weather disasters on agricultural meteorological services.