Radio Science Bulletin 313 - June 2005 - URSI

COMMISSION GThis triennium report was prepared by Prof. ChristianHanuise, Commission G Chair 2002-2005.1. IntroductionDuring the triennium 2002-2005, URSI CommissionG has been active through its Working Groups (WGs) andsponsored symposia and workshops. The Commission hasa website hosted by URSI and an electronic mailing list forcommunicating with people who have expressed an interestin Commission G activities. The address is http://www.ips.gov.au/mailman/listinfo/ursi-commission-g. Themailing list membership is self-managing and theCommission Chair moderates the group. Currently, thereare 709 addresses in the mailing list.2. Working Groups ReportsThe following Working Groups reports have beenprepared by the Working Group Chairs in cooperation withtheir co-chairs.2.1 G1: Ionosonde Network Advisory GroupChair: T. Bullett (USA), Vice-Chair: C Davies (UK),INAG Editor: P. Wilkinson (Australia)Activity within INAG has been low during the lastthree years, according to the relatively few numbers ofarticles in the INAG bulletin and messages in the INAGemail list. This quiet period is likely to end soon, as manyionosouding technical developments are about to becomepublic.The mailing list membership has risen to 247 members.All failed addresses have been purged from this list soalthough the membership is quiet, at least the list is activeand growing at a slow rate.The first INAG Bulletin appeared in September 1969and has proven a useful source of information on ionosondesand ionosonde data and short notes on ionosphericmeasurements and data analysis. For some years now theBulletin has only appeared on the Web. It was decided atthe last Assembly there would be a separate volume per yearand consequently there were three Bulletins issued thistriennium (numbers 64, 65 & 66). Collectively, thisamounted to eight articles. Chris, Phil and I would like tothank the authors of these articles for taking the time tosupport the Bulletin.One further project was commenced during thistriennium but has not yet been completed. During the lasttriennium UAG-23A, the URSI ionogram scalingconventions, was converted to a PDF document and madeavailable through the INAG Bulletin web pages. Currently,John Titheridge’s report on POLAN, UAG-93, is beingconverted to PDF and will be placed on the INAG Websitewhen the conversion is completed.Over the last three years there have been many technicaldevelopments in the ionosonde community. However,most of these are still under development by their respectiveinstitutions, and are not yet ready for announcement or inneed of INAG guidance. One such example is the imminentuse of ionosonde derived electron density profiles by dataassimilation ionosphere models. These models use multipledata types and have optimal estimation algorithms such asthe Kalman filter. These applications require quantifieduncertainty or error estimates in the observations. Once thetechniques for making these error bars are developed andvalidated by the various ionosonde camps, some new dataexchange format is required.Ionosonde owners and operators still practicecommendable levels of data sharing, although internationalfiscal and intellectual property pressures endanger thisfoundation, without which the ionosonde would be relegatedto historical obscurity.Vital data sharing efforts are fundamental to thevarious real time ionosonde data networking efforts. Inaddition to the venerable Digital Ionospheric SoundingSystem network run by the US Air Force, networks ofionosondes are being established or expanded in Europe(DIAS), Australia (IPS), South Africa, and other regions.Data exchange is evolving from a scheme where individualsensors report hourly scaled ionogram characteristics to alocal world data center into a model where sensors reporthigh time resolution ionogram data over the Internet in realtime to regional data or warning centers, with data exchangeoccurring between the regional data centers. Relationaldatabase and web services information technologies arebeing applied to ionosonde networks with greateffectiveness. INAG’s role in this development is one ofsupporting standards of data interchange and advocatingopen and generous exchange of these data.INAG believes it still has a useful role to play andwishes to continue as an URSI Working Group in theforthcoming triennium.2.2 G2: Studies of the ionosphere using beacon satellitesChair: R. Leitinger (Austria), Vice-Chairs: J.A. Klobuchar(USA; until October, 2004); P. Doherty (USA, since October,2004) and P.V.S. Rama Rao (India)The Beacon Satellite Group (BSG) is interdisciplinary,servicing science, research, applications, and engineeringinterests.The Working Group was active in its traditionalfields, namely compilation, exchange and dissemination ofinformation, contact with and exchange of experience withvarious organisations of relevance (ITU-R Study Group 3,the European COST Action 271, Augmentation Systemsfor GPS based satellite navigation, international and nationaladvisory bodies, GPS data retrieval and archivingorganisations, and others), providing advise on request.TheRadio Science Bulletin No 313 (June, 2005) 61