1972—2022年茂名市“龙舟水”的特征分析

Analysis of the Characteristics of“Dragon Boat Rain”in Maoming from 1972 to 2022

基于茂名市所辖5个国家气象观测站1972—2022年逐日降水资料,采用线性趋势分析、M-K检验、Morlet小波分析等方法,分析茂名市“龙舟水”的时空分布特征,结果表明:茂名市“龙舟水”的空间分布呈北多南少,突显3个降水中心且均位于山脉的南坡或高海拔山峰南麓,并与地形作用密切相关;“龙舟水”具有明显的年际变化特征,雨量异常偏多年有8年,异常偏少年有7年,但变化趋势不明显;“龙舟水”年代际变化明显,存在准5年、准12年和准30年的周期变化。当副热带高压偏强、偏西时,茂名市“龙舟水”将明显偏少;反之则偏多。

Based on the daily precipitation data of five national meteorological observation stations under the jurisdiction of Maoming from 1972 to 2022,the spatial and temporal distribution characteristics of“Dragon Boat Rain”in the city were analyzed by means of linear trend analysis,Mann-Kendall test and Morlet wavelet analysis.The results are shown as follows.The spatial distribution of“Dragon Boat Rain”in Maoming was more in the north and less in the south,highlighting three precipitation centers that were all located on the southern slope of mountains or the southern foot of high altitude peaks,and were closely related to the terrain.“Dragon Boat Rain”had obvious inter-annual characteristics,and eight of the study years had anomalously more rainfall and seven had anomalously less rainfall,though the change trend was not obvious.“Dragon Boat Rain”changed significantly on the decadal scale,with periodic change of quasi-5,-12,and-30 years.When the subtropical high was strong and westward,the“Dragon Boat Rain”in Maoming would be significantly less and otherwise was true.