太阳风对流效应对CME渡越时间的影响  

Influence of Convection Effects of Solar Wind Speed on CME Transit Time

作　　者：孙路远 SUN Luyuan(State Key Laboratory of Space Weather, National Space Science Center Chinese Academy of Sciences, Beijing 100190 University of Chinese Academy of Sciences, Beijing 100049)

机构地区：[1]中国科学院国家空间科学中心空间天气学国家重点实验室,北京100190 [2]中国科学院大学,北京100049

出　　处：《空间科学学报》2016年第6期828-836,共9页Chinese Journal of Space Science

基　　金：国家自然科学基金项目资助(40874078)

摘　　要：基于Gopalswamy预报日冕物质抛射(CME)渡越时间的经验模型,选取1996—2007年间52个与地磁效应Dst<-50nT相关的CME事件以及10个引起特大磁暴(Dst<-200nT)的CME事件,结合ACE卫星在1 AU处的太阳风观测资料,分析背景太阳风对流效应对CME到达1 AU处渡越时间预报的影响.对于52个CME事件,考虑太阳风对流效应的影响后,预报的标准偏差由16.5 h降为11.4 h,修正后的误差分布趋向于高斯分布,并且68%事件的预报误差小于15 h.对于10个引起特大磁暴的CME事件,考虑太阳风对流效应的影响后,预报的标准偏差由10.6 h降低到6.5 h,其中6个事件的预报误差小于5 h.研究结果表明,对于CME事件,考虑背景太阳风对流效应的影响可以降低预报CME渡越时间的标准偏差,说明太阳风对流效应对预报CME事件渡越时间具有重要作用.Based on the experiential predicting model,52 CME events which cause geomagnetic storms Dst〈-50 nT,and 10 CME events which cause significant geomagnetic storms（Dst〈-200 nT）in 1996-2007 are selected,and mix with the observation data of interplanetary solar wind and ICME that are collected by ACE satellite at 1 AU,convection effects of ambient solar wind speed on the CME transit time from the Sun to the Earth are analyzed.The results show that significant improvement on the predicting transit time of CME events after taking the convection effects into account has been obtained.For the 52 CME events of Dst-50 nT,the prediction standard difference is reduced from 16.5 to 11.4 hours,and the prediction error is less than 15 hours for 68%of these events.For the 10 CME events（Dst 〈- 200 nT）,the prediction standard difference is reduced from 10.6 to 6.5 hours.Furthermore,the prediction error of 6 events among these 10 events is less than 5 hours.The study identifies the importance of convection effects of solar wind speed on the prediction of CME transit time.

关 键 词：日冕物质抛射 磁暴 背景太阳风速度 

分 类 号：P353.8[天文地球—空间物理学]