Statistical Study of the Effect of Different Solar Wind Types on Magnetic Storm Generation During 1995–2016

Abstract

This paper is a continuation of the research conducted by Nikolaeva et al. (2015, 2017), in which the possible difference in the generation of magnetic storms induced by different large-scale types of solar wind (SW) streams (corotating interaction regions (CIRs), sheaths, magnetic clouds (MCs), and ejecta) were discussed. It was shown in these works that sheath- and CIR-induced magnetic storms demonstrate the greatest geoeffectiveness for the period 1976–2000 with the coupling function introduced by Burton et al. (1975), which couples the integral electric field of the SW Ey = VBz to the Dst and Dst* indices. The use of 12 other coupling functions with different interplanetary parameters and magnetosphere states available in the literature has shown that their efficiency for each type of SW streams depends on the type of function used. In this paper, we study the generation efficiency of the main storm phase for the same four stream types (CIR, sheath, MC, and ejecta) based on OMNI data for the period 1995–2016, which contains a more complete set of data on SW parameters. The results confirm that magnetic storm generation depends on the type of interplanetary source and the high efficiency of the coupling function in the form of an integral of Ey for sheath and CIR streams. The problems of the applicability of the coupling functions used to predict magnetic storms are discussed.