Classification of solar wind structures and intense geomagnetic storm   alarms with self-organizing maps

doi:10.1016/j.asr.2004.06.017

CORC > 北京大学 > 地球与空间科学学院

	Classification of solar wind structures and intense geomagnetic storm alarms with self-organizing maps
	Tian, JH ; Zhang, JC ; Pu, ZY
刊名	space weather
	2005
关键词	space weather solar wind structures intense geomagnetic storms self-organizing maps NEURAL-NETWORKS PREDICTION
DOI	10.1016/j.asr.2004.06.017
英文摘要	Intense geomagnetic storms (D-st <-100nT) usually occur when a large interplanetary duskward-electric field (with Ey > 5 mV m(-1)) lasts for more than 3 h. In this article, a self-organizing map (SOM) neural network is used to recognize different patterns in the temporal variation of hourly averaged Ey data and to predict intense storms. The input parameters of SOM are the hourly averaged Ey data over 3 h. The output layer of the SOM has a total of 400 neurons. The hourly Ey data are calculated from solar wind data, which are provided by NSSDC OMNIWeb and ACE spacecraft and contain information on 143 intense storms and a fair number of moderate storms, weak storms and quiet periods between September 3, 1966 and June 30, 2002. Our results show that SOM is able to classify solar wind structures and therefore to give timely intense storm alarms. In our SOM, 21 neurons out of 400 are identified to be closely associated with the intense storms and they successfully predict 134 intense storms out of the 143 ones selected. In particular, there are 14 neurons for which, if one or more of them are present, the occurrence probability of intense storms is about 90%. In addition, several of these 14 neurons can predict big magnetic storm (D-st <= - 180 nT). In summary, our method achieves high accuracy in predicting intense geomagnetic storms and could be applied in space environment prediction. (c) 2005 COSPAR. Published by Elsevier Ltd. All rights reserved.; Engineering, Aerospace; Astronomy & Astrophysics; Geosciences, Multidisciplinary; Meteorology & Atmospheric Sciences; SCI(E); EI; 1; ARTICLE; 12,2005; 2372-2377; 36
语种	英语
内容类型	期刊论文
源URL	[http://ir.pku.edu.cn/handle/20.500.11897/254212]
专题	地球与空间科学学院
推荐引用方式 GB/T 7714	Tian, JH,Zhang, JC,Pu, ZY. Classification of solar wind structures and intense geomagnetic storm alarms with self-organizing maps[J]. space weather,2005.
APA	Tian, JH,Zhang, JC,&Pu, ZY.(2005).Classification of solar wind structures and intense geomagnetic storm alarms with self-organizing maps.space weather.
MLA	Tian, JH,et al."Classification of solar wind structures and intense geomagnetic storm alarms with self-organizing maps".space weather (2005).