Reply to comment on “Coronal mass ejections, interplanetary ejecta and geomagnetic storms” by Gopalswamy et al

• Published in: Geophysical research letters Vol. 30; no. 24; pp. 2233 - n/a
• Main Authors: Cane, H. V., Richardson, I. G.
• Format: Journal Article
• Language: English
• Published: Goddard Space Flight Center American Geophysical Union 01.12.2003; Blackwell Publishing Ltd; AGU
• Subjects: Coronal mass ejections; Ejecta, driver gases, and magnetic clouds; Interplanetary Physics; Interplanetary shocks; Solar Physics; Solar Physics, Astrophysics, and Astronomy
• ISSN: 0094-8276; 1944-8007
• DOI: 10.1029/2003GL017685

The comment of Gopalswamy et al. (thereafter GMY) relates to a letter discussing coronal mass ejections (CMEs), interplanetary ejecta and geomagnetic storms. GMY contend that Cane et al. incorrectly identified ejecta (interplanetary CMEs) and hypothesize that this is because Cane et al. fail to understand how to separate ejecta from "shock sheaths" when interpreting solar wind and energetic particle data sets. They (GMY) are wrong be cause the relevant section of the paper was concerned with the propagation time to 1 AU of any potentially geoeffective structures caused by CMEs, i.e. upstream compression regions with or without shocks, or ejecta. In other words, the travel times used by Cane et al. were purposefully and deliberately distinct from ejecta travel times (except for those slow ejecta, approx. 30% of their events, which generated no upstream features), and no error in identification was involved. The confusion of GMY stems from the description did not characterize the observations sufficiently clearly.