摘要
采用广西逐日和逐小时降雨数据,统计分析广西十万大山南侧雨窝的时空分布特征和变化趋势,并采用实况、云图雷达、NCEP再分析格点资料,选取弱强迫天气形势下典型的雨窝暴雨个例,进行个例分析和合成分析,对广西雨窝暴雨的成因进行初步探讨。结果表明:(1)十万大山南麓为广西的雨窝,与周边区域对比,广西十万大山南侧为降雨中心,也是中国大陆年降雨量最大、年暴雨日数最多的地方。(2)作为雨窝的代表站,东兴市雨量丰沛,降雨集中,降雨的月季变化为单峰型,7月为降雨量的高峰月,东兴市年降雨量、四季雨量的变化趋势不明显,但汛期的雨量呈减少的趋势;雨日出现时间较分散,雨日逐月变化呈现出多峰结构,年雨日、四季雨日、汛期雨日均呈减少趋势。暴雨频繁,暴雨和短时暴雨均集中出现在6-8月,7月达到高峰,短时暴雨出现在05-08时的可能性最大,12时到次日00时是低谷,暴雨和短时暴雨的时间趋势变化特征均不显著。(3)广西雨窝位于低纬地区,来自北部湾海洋的暖湿气流把源源不断的水汽和不稳定能量输送到广西沿海上空,遇到十万大山地形抬升和水汽辐合,产生的雷暴雨团沿山脉走向移动,产生“列车效应”而形成,广西雨窝的成因和北部湾及十万大山的地形密切相关。
Using daily and hourly precipitation data of Guangxi Province,the spatio-temporal distribution characteristics and changing trend of the rain nest in the south side of Shiwan Mountain of Guangxi are statistically analyzed.In addition,based on the observation data,cloud image,radar,NCEP reanalysis grid data and the selected typical rainstorm cases under weak forcing weather conditions,the case analysis and synthetic analysis are carried out and the causes of the rain nest in Guangxi are preliminarily discussed.The results show that:(1)The southern foot of Shiwan Mountain is the rain nest in Guangxi.Compared with the surrounding areas,the south side of Shiwan Mountain is the center of rainfall,and also the place with the largest amount of annual precipitation and the largest number of rainstorm days in China's Mainland.(2)As the representative station of“rain nest”,Dongxing station usually has abundant and concentrated precipitation.The monthly and seasonal variations of rainfall are of single-peak pattern,and July is the peak month of rainfall.The change trends of annual rainfall and seasonal rainfall at Dongxing station are not obvious,but the rainfall in the flood season shows a decreasing trend.The occurrence frequency of rainy days is relatively scattered,and the monthly variation of rainy days presents a multi-peak structure.The annual rainy days,rainy days in four seasons,and rainy days in the flood season all show the decreasing trend.Torrential rains occur frequently in Dongxing.Torrential rain and short-time rainstorms are concentrated in June to August,reaching the peak in July.The short-time rainstorms are most likely to occur between 05:00 and 08:00,with the lowest possibility from 12:00 at noon to 00:00 at midnight.The change characteristics of the temporal trend of heavy rain and short-time rainstorm are not significant.(3)The rain nest of Guangxi is located in area of low latitudes.The warm humid air from the Beibu Gulf Ocean transports steady streams of moisture and unstable energy to the coast
作者
黄滢
黄小燕
林文桦
何立
刘金裕
莫权芳
Huang Ying;Huang Xiaoyan;Lin Wenhua;He Li;Liu Jinyu;Mo Quanfang(Fangchenggang Meteorological Office of Guangxi Province,Fangchenggang 538001,China;Guangxi Institute of Meteorological Sciences,Nanning 530000,China)
出处
《气象与环境科学》
2023年第3期47-54,共8页
Meteorological and Environmental Sciences
基金
广西自然科学基金项目(2018GXNSFAA281281)
中国预报员专项(CMAYBY2020-099)
中国气象局风云卫星应用先行计划项目(FY-APP-2021.0112)
防城港市科学研究与技术开发计划(防科AB21014037)。
关键词
雨窝
十万大山
降雨特征
成因
rain nest
Shiwan Mountain
precipitation characteristics
causes
