摘要
利用1961—2018年湖北省68站逐日降水资料和美国国家海洋和大气管理局(NCEP/NCAR)环流、海温资料,分析了湖北省春季降水低频特征,并讨论了其年际变化与海温的联系。结果表明:(1)湖北省春季降水存在显著的准双周低频周期。春季涝(旱)年,准双周活动活跃(不活跃)。(2)春季印度洋和黑潮海温分别通过影响中低纬、日本海附近不同区域上空的环流,进而影响湖北省春季降水的低频活动。(3)2018年受黑潮海温异常偏暖的影响,日本海附近500 hPa高度场呈正距平,具有明显的低频振荡特征,其后部东南气流和华南上空的西南气流构成了暖切,从而给湖北省带来低频降水,造成当年春季降水准双周活动指数异常。
Using the daily precipitation data of 68 stations in Hubei and NCEP/NCAR circulation reanalysis data,the low-frequency characteristics of spring rainfall and its relationship with SST are studied.The results indicate that the quasi-biweekly oscillation of precipitation is obviously in spring over Hubei.Biweekly activity strengthens in the spring flood years while weakens in the spring drought years.The sea surface temperature anomalies(SSTA)of the Indian Ocean and Kuroshio in spring can cause circulation anomaly over the mid-low latitudes and Japan Sea,and then affect the low-frequency activity of spring precipitation in Hubei Province.Under the background of anomaly warmer SSTA of Kuroshio in the 2018 spring,there existed a positive anomaly of 500 hPa height field over the Japan Sea.This anomaly had significant low-frequency oscillation.The southeast flow in the rear part of this anomaly constituted the warm shear with the southwest flow from South China,causing low-frequency rainfall over Hubei.All these resulted in biweekly active abnormality.
作者
李程
肖莺
任永建
LI Cheng;XIAO Ying;REN Yongjian(Huanggang Meteorology Service Center,Hubei,Huanggang 438000;Wuhan Reginal Climate Center,Wuhan 430074;Hubei Meteorology Service Center,Wuhan 430074)
出处
《气象科技》
2022年第3期361-368,共8页
Meteorological Science and Technology
基金
湖北省烟草公司科技项目(027Y2021-021)
湖北省气象局科技项目(2021Y17)
国家重点研发计划CMME(2017YFC1502306)
中国长江电力股份有限公司项目(2417020001)资助。
关键词
春季降水
低频特征
印度洋海温
黑潮海温
low-frequency characteristics
spring rainfall
Indian Ocean SST
Kuroshio SST
