The Global Solar Magnetic Field and the Magnetic Cloud Structure

N. Gopalswamy, P. Makela, and S. Yashiro

NASA Goddard Space Flight Center, Code 695, Greenbelt, MD 20771, USA

A close connection between the magnetic field of the Sun and the magnetic field in interplanetary coronal mass ejections (ICMEs) is expected based on source location, CME kinematics, and the eruption process (magnetic reconnection). This is especially true when one considers ICMEs with flux-rope structures, viz., the magnetic clouds. While the internal structure of the magnetic clouds is related to the active region magnetic structure, the magnetic field in the sheath (the region between the magnetic cloud and the shock) is expected to be related to the heliospheric field overlying the source active region. We use the data from solar cycle 23 and previous cycles to show that the 22-year magnetic cycle is revealed in the distribution of various types of magnetic clouds (unipolar and bipolar).