*************************** ** THE GEM MESSENGER ** *************************** Volume 16, Number 22 August 30, 2006 ---------------------------------------------------------------------------- Session Summaries for the Inner Magnetosphere/Storms Campaign At the GEM 2006 Summer Workshop, Snowmass, CO, June 26-30 ---------------------------------------------------------------------------- From: Mike Liemohn This was the final year for the Inner Magnetosphere/Storms Campaign at the GEM Workshop. It was a lively and active year, nonetheless, and the IM/S Campaign held 8 breakout sessions and sponsored 2 plenary session tutorials. All of the sessions were held jointly by the three IM/S Working Groups (Plasmasphere and Ring Current, Radiation Belts, and ULF Waves) with no parallel IM/S sessions, allowing everyone to participate in all of the IM/S discussions. The two plenary session tutorial presentations were Kazue Takahashi of Johns Hopkins University's Applied Physics Laboratory and Mike Liemohn of the University of Michigan. Takahashi gave a review of magnetoseismology, a technique of extracting magnetospheric mass density by analyzing the transit times for ULF pulsations to propagate from the magnetopause to the ground along various paths. Liemohn presented highlights of research results during the IM/S campaign regarding the plasmasphere and ring current. In addition to these two plenary session tutorials, Richard Thorne gave the student-sponsored tutorial on the physical processes governing the radiation belts, in particular focusing on the advancements during the IM/S campaign. Regarding the IM/S Assessment Challenge, 20 papers were submitted to the special section of the Journal of Geophysical Research. Online publication of these papers should begin any time now, and the print version of the special section will appear in the November 2006 issue. Please have a read through these papers as they appear online and in print with JGR. Below are individual summaries for each of the 8 sessions held at the GEM Workshop. A big thanks of gratitude is extended to all of the conveners, who devoted time to the organization, running, and summarizing of their sessions. The IM/s Campaign is now officially over, but the inner magnetospheric research community hopes to remain an integral and active part of the GEM program, and we hope to continue to have a presence at future GEM Workshops. Session 1: Inner magnetospheric M-I Coupling (joint with MIC Campaign) Conveners: Dennis Gallagher and Jeff Hughes IM/S breakout #1 was a joint session between working group 1 and the Magnetosphere-Ionosphere Campaign (MIC) on the topic of inner magnetosphere coupling. Only a few talks were presented, however there was considerable discussion. A new theoretical treatment of Alfvèn wave propagation was presented by Bob Lysak and Jesse Woodroffe. This represents a new opportunity for using more sophisticated tools to interpret mixed mode coupling of low frequency waves to the ground. Local time dependent plasma sheet injection and the coupling between region 1 and 2 current systems were shown to be unresolved issues by Yihua Zheng, who presented a detailed region 2-ring current modeling discussion, involving strong polar cap potential, ionospheric conductivity, and plasma sheet density dependencies. A connection between energetic precipitating particles and the formation of nitric oxide and its possible influence on lower altitude ozone and atmospheric climatology was discussed by Dan Baker. While this magnetospheric-atmospheric connection is not new, the discussion emphasized the need to pursue this unresolved relationship. Observations from the IMAGE spacecraft instrumentation are still providing new results in spite of its December 2005 "failure to communicate". One such new tentative result is the ability to determine two-dimensional thermal plasma flow velocities from the extreme ultraviolet imager (EUV), discussed by Dennis Gallagher. If the analysis technique proves out, it will be possible to determine flows and hence electric fields broadly throughout the inner magnetosphere whenever a series of good EUV observations are available. The assembled group discussed at length whether is s desirable to continue to discuss mid-latitude/inner magnetosphere MI coupling within GEM and if so how to do this. The MIC campaign has not focused on this region because until now it has been covered by the IM/S campaign. Since the IM/S campaign is ending, the group expressed a strong interest in extending the MIC to include inner magnetosphere-ionosphere coupling. No clear preference was given on how to do that, but adding a new working group to MIC and making use of focused discussion groups were both considered viable options. Session 2: Inner-outer magnetosphere coupling (joint with GI Campaign) Conveners: Margaret Chen and David Sibeck The main consensus of this session was that the connection between the inner magnetosphere and the plasma sheet and its sources is very important. There were talks on the relationship between the plasma sheet and ring current (B. Lavraud, M.-C. Fok, V. Jordanova). Plasma sheet characteristics such as density, temperature, and their variation with magnetic local time (MLT) affect the strength and morphology of the ring current. For example, it was shown that a cold dense plasma sheet tends to produce a more intense ring current. There were a few speakers (G. Reeves, M.-C. Fok, Y. Shprits) who elucidated the relationship between the plasma sheet and the radiation belt. Substorm injections, MLT-variations of the plasma sheet distribution, and field-line stretching affect radiation-belt dynamics. The relationships between the solar wind, plasma sheet ions, and the ring current was discussed by C.-P. Wang who summarized his statistical analysis of GEOTAIL data. It was found that high solar wind density leads to higher density in the two flanks and a lower temperature. It is expected that this would lead to an enhancement of the ring current plasma pressure in the post midnight sector. On the other hand, high solar wind speed leads to a higher plasmasheet temperature and lower density. One would expect that this would lead to an enhancement of the ring current in the pre-midnight sector. E. Burin des Roziers talked about the relationships between the solar wind, plasma sheet electrons, and the radiation belt from analysis of Cluster data. He found no correlation between solar wind density and the density of 10’s keV plasmasheet electrons. However, he found a positive correlation between solar wind velocity and density of 10’s keV plasma sheet electrons. Finally, the role of global fields on the inner magnetospheric dynamics was discussed (P. Toivanen, M.-C. Fok). The ring current tends to more sensitive to the electric field and its variation while the radiation belt tends to be more responsive to the magnetic field and its variation. Session 3: ULF Wave Index for Inner Magnetospheric Studies Conveners: Brian Fraser and Ian Mann Recent studies have highlighted the role of ULF waves in inner magnetosphere dynamics, including the response of the MeV electrons in the outer radiation belt. This session was devoted to discussion of ULF wave studies that are contributing to the development of ULF wave indices that may be used to describe the wave state of the inner magnetosphere and radiation belt environment. Of particular interest in this session were ULF wave studies which provide information about the characteristics of ULF waves with a strong radiation belt response. The ultimate aim is to arrive at indices that may be used in statistical or space weather studies, for example, relating to the energisation of electrons to MeV energies by ULF wave processes. Informal presentations of recent results from data analysis or theoretical modeling of the ULF wave-MeV electron interaction, or of prototype ULF indices, were given. Session 4: Plasmaspheric density from ULF wave observations Conveners: Mark Moldwin and Dennis Gallagher The session described highlights of recent results that use ULF resonance techniques and other complementary techniques that have contributed to our understanding of the distribution of heavy ions and mass density in the magnetosphere. Emphasis was placed on combining the ULF resonance estimates of mass density with other independent measurements (TEC, radio sounding, IMAGE EUV, in situ observations) to both validate the technique and extend the observations to provide information on the mass composition of the inner magnetosphere. Reports from new arrays (McMAC and SAMBA) and the effect of including the most recent magnetic field models were also discussed. Session 5: Radiation Belt Source Processes Conveners: Richard Thorne and Brian Fraser This session was devoted to a discussion of the relative contribution of various source processes for the radiation belts, including radial diffusion and local stochastic acceleration. Informal presentations of recent results were presented of both theoretical modeling and data analysis. Session 6: Radiation Belt Losses Session Conveners: Geoff Reeves and Paul O'Brien Radiation belt losses have been an important topic throughout the IM/S campaign and this session tried to capture and summarize what has been learned through the campaign, what the current cutting edge science questions are, and how research on radiation belt losses might be kept vibrant over the next few years. Lively discussion occurred regarding radiation belt losses in the contexts of sources, acceleration, magnetosphere/ionosphere/atmosphere coupling, wave-particle interactions, measurement techniques, and other related areas. Results were presented from theory, modeling, and observations from satellite, balloon, rocket, and ground-based instruments. Session 7: IM/S Challenge Results and GGCM Coupling Issues (joint with GGCM) Conveners: Mike Liemohn and Jimmy Raeder Results for the two phases (WG1 and WG2 storm selections) of the IM/S Assessment Challenge (IMSAC) were presented in this session by numerous contributors to the JGR special section. Rather than standard presentations of findings, however, the discussion was focused on scientific and numerical issues relating to inner magnetospheric modules within the context of a larger Geospace General Circulation Model (GGCM). Presentations were given on science results that highlight the need for and difficulties of code coupling. Session 8: Diagnosis and prognosis of the IM/S Campaign Conveners: Mike Liemohn and the WG chairs This session was the final official IM/S session of GEM. Discussions were held about where we have been, where we are going, and the near- and long-term future of inner magnetospheric research. A few recap presentations were given, but most of the time was spent discussing how to continue the momentum and cohesion of the IM/S Campaign now that it is ending as a formal campaign within the GEM program. The debate of Focus Groups vs. Campaigns was extensively discussed, and opinions differed among the crowd about how to proceed. Many good ideas for follow-on campaigns or focus groups were mentioned, and hopefully these suggestions will become reality sometime in the near future. The thought of adapting one or more AGU sessions into a GEM-style format was also discussed, and is presently being pursued for the Spring AGU meeting. The concept of our own inner magnetospheric workshop was discussed, but not immediate action items resulted from that idea. It was concluded that we should try to remain within the GEM structure, and either Campaign mode or Focus Group mode will allow us to do that. Final Note from the IM/S Campaign Chair I would like to thank all of those who have served as leaders within the IM/S Campaign structure. Specifically, I thank the present working group chairs (Dennis Gallagher, Margaret Chen, Richard Thorne, Reiner Friedel, Mark Moldwin, and Brian Fraser), the past IM/S Campaign chairs (Mary Hudson and Anthony Chan), and the past working group chairs (Geoff Reeves, Janet Kozyra, Jim Horwitz, and Dan Baker). Finally, I would like to thank the National Science Foundation, and in particular the Magnetospheric Physics program director, Kile Baker, for continued support of the GEM program. Sincerely yours, Mike Liemohn (Former) IM/S Campaign Chair +-------------------------------------------------------------------------+ |To subscribe GEM Messengers, send an e-mail to | | with the following command in the body of your e-mail message: | | subscribe gem | |To remove yourself from the mailing list, the command is: | | unsubscribe gem | | | |To broadcast a message to the GEM community, please contact Peter Chi at | | | |Please use plain text as the format of your submission. | | | |URL of GEM Home Page: http://www-ssc.igpp.ucla.edu/gem/Welcome.html | |Workshop Information: http://gem.rice.edu/~gem | +-------------------------------------------------------------------------+