Mursula, K., & Holappa, L. (2017). Principal Component Analysis of Geomagnetic Activity: New Information on Solar Wind. Proceedings of the International Astronomical Union, 13(S335), 197-200. doi:10.1017/S1743921317010146
Principal component analysis of geomagnetic activity : new information on solar wind
|Author:||Mursula, Kalevi1; Holappa, Lauri1|
1ReSoLVE Centre of Excellence, Space Climate Research Unit, University of Oulu, Finland
|Online Access:||PDF Full Text (PDF, )|
|Persistent link:|| http://urn.fi/urn:nbn:fi-fe2018091135460
Cambridge University Press,
|Publish Date:|| 2019-01-24
We use the principal component analysis to study geomagnetic activity at annual resolution using a network of 26 magnetic stations in 1966-2015, and an extended network of 40 stations in 1980-2015. The first principal component describes the long-term evolution of global geomagnetic activity, and has an excellent correlation with indices like the Kp/Ap index. The two networks give identical results for the first principal component. The second principal component is highly correlated with the annual percentage of high-speed streams (HSS). The extended network has a slightly higher sensitivity to HSSs. We verify the non-trivial latitudinal distribution of the second empirical orthogonal function. We find that the amplitude of the 22-year variation of geomagnetic activity has a closely similar latitudinal distribution as the second empirical orthogonal function. This verifies that the 22-year variation of geomagnetic activity is related to HSSs. The most likely cause is the Russell-McPherron mechanism.
Proceedings of the International Astronomical Union
|Pages:||197 - 200|
Proceedings IAU Symposium No. 335, 2017. Space Weather of the Heliosphere: Processes and Forecasts. 17-21 July, University of Exeter, United Kindom
|Host publication editor:||
Malandraki, O. E.
Symposium of the international astronomical union (IAUS)
|Type of Publication:||
A4 Article in conference proceedings
|Field of Science:||
115 Astronomy and space science
We acknowledge the financial support by the Academy of Finland to the ReSoLVE
Centre of Excellence (project no. 272157).
|Academy of Finland Grant Number:||
272157 (Academy of Finland Funding decision)
© International Astronomical Union 2018