The GPS ionospheric working group

The first GPS ionospheric working group workshop was held 10–11 November 2003 at the MIT Haystack observatory in Westford, MA. The purpose of this workshop was to foster an environment of collaboration on scientific projects, software development and long-range planning issues involving GPS. A prime motivation of this group is to integrate the use of GPS data more completely within the larger sphere of atmospheric research. For example, a primary goal is a closer coupling of GPS measurements with data from other atmospheric sensors, such as atmospheric imagers and the incoherent scatter radar observations. It is also desirable to make GPS data more accessible to atmospheric researchers. GPS is at the forefront of utilizing information from integrated ground-based atmospheric systems. By combining GPS data from the ground-based and space-based network of receivers, spatial and temporal changes in the global distribution of the total electron content (TEC) can be monitored, providing a new view of the large and meso-scale characteristics and dynamics of the plasmas of the extended ionosphere. GPS observations when processed this way are helping to increase the understanding of the driving forces between the coupled spheres of Earth’s upper atmosphere. The workshop drew participation from approximately 25 ionospheric researchers, including several from the international community. Topics discussed at the workshop included the development of new software receivers, the impact of ionospheric phenomena on operational systems, and GPS observations of ionospheric redistribution and implications for magnetospheric–ionospheric (MI) coupling. The format of this meeting was informal, and a workshop environment was adhered to. Workshop participants included representatives from MIT’s Haystack observatory, the Jet Propulsion Laboratory (JPL), Cornell University, Boston College, the University of Colorado, the Air Force Research Laboratory, the Naval Research Laboratory, and the University of Texas at Austin. International participants included representatives from the University of Calgary, the University of New Brunswick, the Institute for Research on Electromagnetics of the Italian National Research Council (IROE-CNR), the University of Bath, and the Technical University of Catalonia. The workshop began with each of the participants presenting a short summary of their current efforts. These efforts included numerous TEC and scintillation studies using GPS, studies of equatorial anomaly dynamics using multi-instruments, ionospheric storm modeling, ionospheric storm studies using GPS networks, ionospheric tomography, near-real time TEC map generation, ionospheric studies in support of WAAS, data assimilation, scintillation receiver development, Traveling Ionospheric Disturbances (TIDs) studies, data processing, software development, and the development of new receivers. Following the introductions, longer presentations were given. The first was given by Dr. Bruce Tsuratani of the JPL and he discussed the relationship of the ionosphere to interplanetary shock electric fields. He has been analyzing the 5–6 November 2001 interplanetary shock/electric field event using space-borne GPS receiver data and altimeter data from TOPEX/Poseidon. In particular he is interested in the magnetospheric convection electric fields and the convection of ionospheric plasmas by these electric fields. Much discussion ensued on the myriad of unusual effects. Dr. Brent Ledvina of Cornell University gave a brief presentation on Global Navigation Satellite System (GNSS) receivers, which include GPS and Galileo receivers. The Received: 16 March 2004 / Accepted: 26 March 2004 Published online: 14 July 2004 a Springer-Verlag 2004