Comment on "Geoeffectiveness of halo coronal mass ejections" by N. Gopalswamy, S. Yashiro, and S. Akiyama

TL;DR

This paper comments on previous studies of halo coronal mass ejections' geoeffectiveness, discussing discrepancies in reported effectiveness rates and providing insights into the reasons behind these differences.

Contribution

It offers a critical perspective on the varying reported geoeffectiveness of halo CMEs and clarifies potential causes for the conflicting results.

Findings

Reported geoeffectiveness varies from 35% to over 80%.

Differences may stem from definitions of halo CMEs and geoeffectiveness.

The paper emphasizes the need for standardized criteria.

Abstract

Comment on paper: Gopalswamy, N., S. Yashiro, and S. Akiyama (2007), Geoeffectiveness of halo coronal mass ejections, J. Geophys. Res., 112, A06112, doi:10.1029/2006JA012149 Gopalswamy et al. [2007] studied the geoeffectiveness of halo coronal mass ejections (CMEs) on the basis of solar observations during 1996-2005 and found that the geoeffectiveness of 229 frontside halo CMEs was 71%. Recently for observations of 305 frontside halo CMEs during 1997-2003 the geoeffectiveness was found to be 40% [Kim et al., 2005]. Complex analysis of both solar and interplanetary measurements showed that the geoeffectiveness of frontside halo CMEs is likely to be about 50% [Yermolaev et al., 2005; Yermolaev and Yermolaev, 2006]. Gopalswamy et al. [2007] did not discuss possible causes of this difference and were limited only to the general words: "The reason for the conflicting results (geoeffectiveness of CMEs ranging from 35% to more than 80%) may be attributed to the different definition of halo CMEs and geoeffectiveness." So, here we shall present our point of view on high geoeffectivenees of CME obtained in paper by Gopalswamy et al. [2007].