干旱气象 ›› 2021, Vol. 39 ›› Issue (4): 554-562.

• 论文 • 上一篇    下一篇

湖南省汛期降水结构演变特征分析

蒋元华,曾向红,段丽洁,汤亦豪,吴浩#br#

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  1. (湖南省气候中心,湖南 长沙 410118)
  • 出版日期:2021-08-31 发布日期:2021-09-13
  • 通讯作者: 曾向红(1962— ),女,硕士,高级工程师,主要从事气候应用服务研究. Email: 627694002@qq.com。
  • 作者简介:蒋元华(1987— ),男,硕士,工程师,主要从事气候与气候变化研究. Email: 474674090@qq.com。
  • 基金资助:
    湖南省气象局短平快课题(XQKJ21B006)、海绵城市建设集成技术研究及工程应用示范项目(GCCT-KJYF-01)、长沙市雨花区重大科技专项“智慧型海绵城市建设管控平台的研究与应用”(YHKJ-2018-ZDG-02) 和中国气象局干旱气象科学研究基金项目(IAM201708)共同资助

Variation Characteristics of Precipitation Structure During Flood Season in Hunan Province

JIANG Yuanhua, ZENG Xianghong, DUAN Lijie, TANG Yihao, WU Hao   

  1. Hunan Climate Center, Changsha 410118, Hunan
  • Online:2021-08-31 Published:2021-09-13

摘要: 摘要:利用1980—2018年湖南省汛期96个地面气象观测站逐小时降水资料,以降水事件发生频率和降水量贡献率作为重要指标,分析湖南省汛期降水结构的时空演变特征。结果表明:(1)随历时增长,降水事件发生频率呈幂函数规律减小,降水量贡献率则呈线性增加趋势。短历时降水事件发生频率高,降水量贡献率低;长历时降水事件发生频率低,但降水量贡献率高,是汛期降水主体。短历时降水事件发生频率和降水量贡献率湘南高于湘北,而长历时降水事件发生频率和降水量贡献率湘北高于湘南。(2)近10 a短历时降水事件发生频率和降水量贡献率都呈线性增加趋势,而长历时降水事件发生频率和降水量贡献率则呈下降趋势。(3)各量级降水事件发生频率随降水量等级增加呈幂函数规律减小,降水量贡献率则随降水量等级增加呈线性上升趋势。暴雨虽然发生频率低,但是汛期降水的贡献主体。小到中雨降水事件发生频率和降水量贡献率大致表现为湘南高于湘北;而大到暴雨降水事件发生频率和降水量贡献率湘北高于湘南。(4)小到大雨降水事件发生频率年际变化不显著,暴雨等级降水事件发生频率呈显著增加趋势。小雨降水事件降水量贡献率年际变化不显著,但是中雨和大雨等级降水事件降水量贡献率呈显著下降趋势,暴雨等级降水事件降水量贡献率呈显著上升趋势。

关键词: 降水结构, 降水历时, 降水量等级, 降水量贡献率

Abstract: Based on hourly precipitation data from 96 meteorological stations during the flood season from 1980 to 2018 in Hunan Province, the occurrence frequency and contribution rate to the total precipitation amount were used as important indicators, and the spatialtemporal evolution characteristics of precipitation structure in Hunan Province during the flood season were analyzed. The results are as follows: (1) The occurrence frequency of rainfall events decreased by power function with increasing durations, while its contribution rate to the total precipitation amount of rainfall events increased linearly with increasing duration. The occurrence frequency of short duration rainfall event was high, while its contribution rate to the total precipitation amount was low. The occurrence frequency of long duration rainfall event was low, but contribution rate to the total precipitation amount was high and long duration rainfall event was the main body of precipitation in flood seasons. Both the occurrence frequency and contribution rate to the total precipitation amount of short duration rainfall events  were higher in southern Hunan than in northern Hunan, while the occurrence frequency and contribution rate to the total precipitation amount of long duration rainfall events were higher in northern Hunan than in southern Hunan. (2) In the past 10 years, both the occurrence frequency and contribution rate to the total precipitation amount of short duration rainfall events increased linearly, while the occurrence frequency and contribution rate to the total precipitation amount of long duration rainfall events decreased linearly. (3) Occurrence frequency of all rainfall events decreased by power function with increasing precipitation levels, while contribution rate to the total precipitation amount increased linearly with increasing precipitation levels. Although the occurrence frequency of torrential rainfall event was low, while it was the main contributor to precipitation during the flood season. The occurrence frequency and contribution rate to the total precipitation amount of light to moderate rainfall events were generally higher in southern Hunan than in northern Hunan, while the occurrence frequency and contribution rate to the total precipitation amount of heavy to torrential rainfall events were higher in northern Hunan than in southern Hunan.  (4) The interannual variation of occurrence frequency of light to heavy rainfall events was not significant, but the occurrence frequency of the torrential rain event increased significantly, while the interannual variation of contribution rate to the total precipitation amount of light rainfall events was not significant, but for moderate rain to heavy rainfall event it showed a significant downward trend, and contribution rate to the total precipitation amount of torrential rainfall events showed a significant upward trend.

Key words: precipitation structure, duration of precipitation, precipitation level, precipitation contribution rate

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