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arXiv · 1909.05213

Near-real-time VTEC maps: new contribution for Latin America Space Weather

Luciano Pedro Oscar Mendoza·Amalia Meza·Juan Manuel Aragon Paz
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Abstract

The development of regional services able to provide ionospheric vertical totalelectron content (VTEC) maps and ionospheric indexes with a high spatialresolution, and in near-real-time, are of great importance for both civilianapplications and the research community. We provide here the methodolo-gies, and an assessment, of such a system. It relies on the public GlobalNavigational Satellite Systems (GNSS) infrastructure in South America, in-corporates data from multiple constellations (currently GPS, GLONASS,Galileo and BeiDou), employs multiple frequencies, and produces continen-tal wide VTEC maps with a latency of just a few minutes. To assess theability of our system to model the ionospheric behavior we performed a year-round intercomparison between our near-real-time regional VTEC maps, andVTEC maps of verified quality produced by several referent analysis centers,resulting in mean biases lower than 1 TEC units (TECU). Also, the evalua-tion of our products against direct and independent GNSS-based slant TECmeasurements shows RMS values better than 1 TECU. In turn, ionospheric W-index maps were generated, for calm and disturbed geomagneticscenarios, solely employing our quality verified VTEC maps. The spatial rep-resentation of these W-index maps reflects the state of the ionosphere, with aresolution of 0.5x0.5 degrees. Finally, we conclude that our products, com-puted every 15 minutes, do provide an excellent spatial representation of theregional TEC, and are able to provide the bases for the possible computationof ionospheric W-index maps, also in near-real-time

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Luciano Pedro Oscar Mendoza, Amalia Meza, Juan Manuel Aragon Paz. 2019-09-11. Near-real-time VTEC maps: new contribution for Latin America Space Weather. https://doi.org/10.1016/j.asr.2019.08.045

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