| 摘要: |
| 【 目的】为探寻毕节市夏季(6—8 月）降水的气候及非均匀性特征。【方法】选取毕节市 8 个国家气象站 1961 — 2020 年夏季逐日降水资料，结合降水集中度(PCD)与集中期(PCP) 参数指标，统计分析该地区夏季降水量的时空变化特征。 【结果】毕节市夏季平均降水量为 526 . 8 mm , 单站最大和最小降水量为织金站和威宁站，黔西站、赫章站、纳雍站、大方站、金 沙站、威宁站夏季降水量呈右偏态分布，毕节站和织金站呈左偏态分布。各站逐候降水量均值整体经历了 “上升—下降—持 平—下降—上升 ”阶段，候降水量达到峰值的时段有所差异。候降水量变化相关分析显示各站呈显著的正相关关系，以毕节 站相关性最强。降水集中度与集中期的变化率表明了候降水逐渐往集中趋势发展且最大候降水量出现时段提前。整个地区 候降水量总体分布均匀，相对而言，织金县出现最大候降水量的时段最早，赫章县最晚。Morlet 小波周期特征显示降水集中度 与集中期的第 1 、2 、3 、4 主周期分别为 28 a、23 a、14 a、5 a 和 32 a、16 a、24 a、6 a。【结论】毕节市不同区域夏季降水量区别较 大，整体呈南多北少，东早西晚的特点，夏季降水集中度与集中期仅第 1 主周期在整个时域内表现出显著的振荡周期变化，其 余 3 个主周期显著的振荡周期变化则具有局域性。 |
| 关键词: 毕节市；夏季降水量；集中度；集中期；时空特征 |
| DOI： |
| 投稿时间：2024-02-27修订日期：2024-08-05 |
| 基金项目:贵州省气象局科研业务登记项目（黔气科登〔2022〕12 - 05 号、黔气科登〔2022〕12 - 06 号 |
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| Spatio-temporal Characteristics of Summer Rainfall in Bijie City from 1961 to 2020 |
| CAI Jun,ZHANG Yukui,YU Lyu,YANG Chengmei,GUN Yi,NI Ni |
| (Weining Yi , Hui and Miao Autonomous County Meteorological Station of Guizhou Province;Dafang Meteorological Station of Guizhou Province) |
| Abstract: |
| To explore the climatic and non-uniform characteristics of summer (June to August ) precipitation in Bijie City , this article uses the daily precipitation data from eight national meteorological stations in Bijie City from 1961 to 2020 to statistically analyze the spatio-temporal variation characteristics of summer precipitation in the region combining the parameters of precipitation concentration degree (PCD) and concentration period (PCP) . It is found that the average summer precipitation in Bijie City is 526 . 8 mm. The stations with maximum and minimum precipitation amounts are Zhijin Station and Weining Station . The summer precipitation at the stations of Qianxi , Hezhang , Nayong , Dafang , Jinsha and Weining shows a right skewed distribution , while that at Bijie Station and Zhijin Station is in a left skewed distribution . The pentad precipitation of each station has gone through a stage of " rising-falling-flat-falling-rising " , and there are differences in the time period when the pentad precipitation reaches its peak . The correlation analysis of the changes in the amount of pentad rainfall reveals a significant positive correlation among all stations , with Bijie Station having the strongest correlation . The concentration degree of precipitation and the change rate of concentration period indicate that the pentad precipitation is developing in a gradual concentration trend and the maximum pentad precipitation occurs earlier. The general distribution of precipitation in the entire region is uniform , with Zhijin County having the earliest period of maximum pentad precipitation and Hezhang County having the latest. The Morlet wavelet period characteristics show that the first , second , third and fourth main periods of precipitation concentration degree and concentration period are 28 years , 23 years , 14 years , 5 years and 32 years , 16 years , 24 years and 6 years , respectively. Overall , there are significant differences in summer precipitation in different regions of Bijie City , with an overall trend of " more in the south and less in the north , and earlier in the east and later in the west " . The concentration degree and concentration period of summer precipitation only show significant oscillation period changes in the first main period throughout the time domain , while the significant oscillation period changes in the other three main periods are localized . |
| Key words: Bijie City; summer rainfall; concentration degree; concentration period; spatio-temporal charac- teristics |
