MJO对西藏东部夏季降水的影响
Impact of Madden-Julian Oscillation Activities on Precipitation in Summer over the Eastern Tibet
罗布 1列杰班宗 2黄晓清 3普次仁 4顿玉多吉3
作者信息
- 1. 西藏自治区气象局应急与减灾处 西藏拉萨 850000
- 2. 西藏自治区气象服务中心 西藏拉萨 850000
- 3. 西藏自治区气候中心 西藏拉萨 850000
- 4. 西藏自治区气象台 西藏拉萨 850000
- 折叠
摘要
为解决西藏延伸期降水预报方法少、可预报性低等问题,文章采用带通滤波、时滞相关、合成分析以及基于拉格朗日方法的HYSPLIT模式对MJO与西藏东部夏季降水之间的关系进行了研究.结果表明:首先,MJO对西藏东部夏季降水有显著的影响;其次,MJO第4位相后西藏东部降水有明显的"准20天"低频振荡特征,即在前20天偏低,第20天起降水概率呈指数式增加;最后,对MJO事件和西藏东部个别站夏季降水事件统计关系的个例诊断分析,及后向轨迹追踪模式的模拟证实了降水事件的水汽源头均来自MJO第4位相主体对流区域,进一步验证了MJO活动与西藏东部夏季降水之间存在显著的季节内相关.
Abstract
To solve the problem of few precipitation forecasting methods and low predictability of precipitation during the extended period in Tibet.the relationship between MJO and summer precipitation on the Tibet Pla-teau is studied in this study using the band-pass filtering,the lead-lag(time-delay)correlation,composite(syn-thetic)analysis,and the HYSPLIT model based on the Lagrangian method.The results show that MJO has a sig-nificant impact on summer precipitation on the eastern Tibet(east of 90°E)and the precipitation probability on the eastern Tibet increases exponentially from the 20th day after the fourth phase of MJO,with the highest value appeared on the 28th day.Moreover,through the diagnostic analysis of the statistical relationship between the MJO events and precipitation events at certain stations in particular years using the backward trajectory tracking model simulation,it is confirmed that the water vapor sources of those precipitation events came from the main convection region of the fourth phase of MJO,which further verified the significant intraseasonal correlation be-tween the activity of MJO and summer precipitation on the eastern Tibet.
关键词
MJO/西藏东部/夏季降水Key words
MJO/eastern Tibet/summer precipitation引用本文复制引用
基金项目
西藏自治区科技厅中央引导地方项目(ZYYD2020000036)
中国气象科学研究院青藏高原与极地气象研究所开放项目(ITPP2021K02)
国家自然科学基金项目(41765012)
出版年
2024
NETL
NSTL
维普
万方数据