GPS Ionospheric Scintillations Monitoring at INGV: Scientific Aims and Space Weather Applications
De Franceschi, G.; Alfonsi, L.; Romano, V.
Istituto Nazionale di Geofisica e Vulcanologia

A specially modify GPS receiver for Ionospheric Scintillation and TEC Monitoring (GISTM) was deployed in September 2003 by Istituto Nazionale di Geofisica e Vulcanologia (INGV) at the Italian Arctic station “Dirigibile Italia” in Ny Alesund (79.9° N, 11.9° E, Svalbard, Norway), in the frame of the ISACCO (Ionospheric Scintillations Arctic Campaign Coordinated Observation) project (De Franceschi et al., 2006). The receiver computes and records GPS scintillation indices and Total Electron Content (TEC). Phase and amplitude data, either in raw form or detrended (to remove systematic variations), can also be logged at 50-Hz. Nowadays ISACCO counts on three GISTM receivers at Svalbard (Norway), and one in Antarctica at MZS (74.7° S, 164.1° E). Post processed and raw data are available in near real-time at INGV site: www.eswua.ingv.it. Visiting this web site is possible to access the INGV database, realized to organize and manage the large amount of information acquired by the INGV instruments measuring the ionospheric plasma parameters (Romano et al., 2007). The section of the DB designed for the TEC and scintillations data has been thought to address the needs of space weather as well as of scientific users. Through the web tools is possible to visualize, plot, extract and download the data over Northern Europe and Antarctica. The DB has been also designed thinking to the expansion of the observational network as well as to include models to nowcast and forecast the ionospheric scenario over polar latitudes.

The importance and the amount of the data collected by INGV has encouraged original investigations on the formation of the ionospheric irregularities causing scintillations and on the dynamics of the high latitude plasma under disturbed conditions. International collaborations with groups that manage similar experimental observations and experts of irregularities and scintillations modeling gave rise to several opportunities to exchange expertise and data (Coster et al., 2005; Mitchell et al., 2005; Alfonsi et al., 2007; De Franceschi et al., 2007; Wernik et al., 2007). More recently the INGV data have been used to test scintillations models and techniques of mitigation of the position errors due to scintillations (Alfonsi et al., 2006).

This paper gives a general overview on the scintillations and TEC polar observatories, on the organization of the data collected, on the international collaborations and projects in which INGV is currently involved, on the scientific investigations and on the tests of models and mitigation techniques performed with the INGV measurements.

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