Introduction to violent Sun-Earth connection events of October\textendashNovember 2003

<p>The solar-terrestrial events of late October and early November 2003, popularly referred to as the Halloween storms, represent the best observed cases of extreme space weather activity observed to date and have generated research covering multiple aspects of solar eruptions and their space weather effects. In the following article, which serves as an abstract for this collective research, we present highlights taken from 61 of the 74 papers from the <em>Journal of Geophysical Research</em>, <em>Geophysical Research Letters</em>, and <em>Space Weather</em> which are linked under this special issue. (An overview of the 13 associated papers published in <em>Geophysics Research Letters</em> is given in the work of Gopalswamy et al. (2005a)).</p>