• ionosphere;
  • space weather;
  • radio propagation

[1] The 12th International Ionospheric Effects Symposium (IES2008) was held at the Crowne Plaza Hotel, Old Town, Alexandria, Virginia, 13–15 May 2008. There were ∼150 papers and posters accepted. For those interested, hard copy and electronic versions of the Proceedings of IES2008 can be obtained by contacting the IES manager through the web sites ( or The Proceedings may also be obtained through NTIS book store, Springfield, Virginia.

[2] IES2008 maintained the tradition of the eleven previous symposia that have been held in the Washington, D. C., area since 1975 in that primary sponsorship was from the DOD, notably the Office of Naval Research, ONR. Besides ONR, sponsors for IES2008 included the Air Force Office of Scientific Research, AFOSR, and URSI. IES2008 would not have been successful without the support of a host of cooperating agencies. Special thanks go to Robert McCoy (ONR) for his support over the years.

[3] This special issue is devoted to a selection of IES2008 contributions that introduced new information pertinent to ionospheric radio and space system performance. This includes specification of new techniques, experimental methods, novel data sets, and models of system impairment to name a few items. A major component throughout is the relationship between ionospheric effects and space weather, although contribution to radio science is central. There are thirty papers in the issue, and readers will note a wide variety of topics representative of current issues in ionospheric research, space weather interactions, and system effects. I would like to thank all the reviewers involved in this issue and especially T. Habashy (outgoing Radio Science Editor) and Paul Cannon, who is the current Editor of Radio Science.

[4] The next IES will be convened in the spring of 2011, and we anticipate considerable growth in interest in many of the same topics that are contained in the current special issue, which represents experience largely obtained during solar minimum conditions. As the next solar cycle expands and begins to impact emergent telecommunication systems, it is anticipated that new issues and challenges will be identified (see