30 research outputs found

    Data ingestion into NeQuick 2

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    NeQuick 2 is the latest version of the NeQuick ionosphere electron density model developed at the Aeronomy and Radiopropagation Laboratory of the Abdus Salam International Centre for Theoretical Physics (ICTP) ‐ Trieste, Italy with the collaboration of the Institute for Geophysics, Astrophysics and Meteorology of the University of Graz, Austria. It is a quick‐run model particularly designed for trans‐ionospheric propagation applications that has been conceived to reproduce the median behavior of the ionosphere. To provide 3‐D specification of the ionosphere electron density for current conditions, different ionosphere electron density retrieval techniques based on the NeQuick adaptation to GPS‐derived Total Electron Content (TEC) data and ionosonde measured peak parameters values have been developed. In the present paper the technique based on the ingestion of global vertical TEC map into NeQuick 2 will be validated and an assessment of the capability of the model to reproduce the ionosphere day‐to‐day variability will also be performed. For this purpose hourly GPS‐derived global vertical TEC maps and hourly foF2 values from about 20 ionosondes corresponding to one month in high solar activity and one month in low solar activity period will be used. Furthermore, the first results concerning the ingestion of space‐based GPS‐derived TEC data will be presented.Fil: Nava, B.. The Abdus Salam. International Centre for Theoretical Physics; ItaliaFil: Radicella, S.M.. The Abdus Salam. International Centre for Theoretical Physics; ItaliaFil: Azpilicueta, Francisco Javier. Universidad Nacional de La Plata. Facultad de Ciencias Astronómicas y Geofísicas; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin

    Comparing TOPEX TEC measurements with IRI predictions

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    TEC values obtained from TOPEX satellite were compared with the International Reference Ionosphere (IRI) 2001 model estimates. The present work also shows results of the IRI model with the option of a new topside electron density distribution (NeQuick model). TOPEX TEC measurements, which include years of high and middle to low solar activity (2000 and 2004), were analyzed by binning the region covered by the satellite (±66°) every five degrees of modip. In general, there is good agreement between IRI predictions and Topex measurements. Cases with large disagreements are observed at low and high latitudes during high solar activity. Comparing the model predictions using the default IRI2001 model and the NeQuick topside option show that the default IRI 2001 version represents the observed data in a more realistic way, but appears to be less reliable at high and low latitudes in some cases.Fil: Migoya Orue, Yenca Olivia. Universidad Tecnológica Nacional; ArgentinaFil: S.M. Radicella. Aeronomy and Radiopropagation Laboratory; ItaliaFil: P. Coïsson. Aeronomy and Radiopropagation Laboratory; ItaliaFil: Ezquer, Rodolfo Gerardo. Universidad Nacional de Tucumán. Facultad de Ciencias Exactas y Tecnología. Departamento de Física. Laboratorio de Ionósfera; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán; ArgentinaFil: Nava, B.. Aeronomy and Radiopropagation Laboratory; Itali

    Middle and low latitude ionosphere response to 2015 St. Patrick's Day geomagnetic storm

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    International audienceThis paper presents a study of the St Patrick's Day storm of 2015, with its ionospheric response at middle and low latitudes. The effects of the storm in each longitudinal sector (Asian, African, American, and Pacific) are characterized using global and regional electron content. At the beginning of the storm, one or two ionospheric positive storm effects are observed depending on the longitudinal zones. After the main phase of the storm, a strong decrease in ionization is observed at all longitudes, lasting several days. The American region exhibits the most remarkable increase in vertical total electron content (vTEC), while in the Asian sector, the largest decrease in vTEC is observed. At low latitudes, using spectral analysis, we were able to separate the effects of the prompt penetration of the magnetospheric convection electric field (PPEF) and of the disturbance dynamo electric field (DDEF) on the basis of ground magnetic data. Concerning the PPEF, Earth's magnetic field oscillations occur simultaneously in the Asian, African, and American sectors, during southward magnetization of the B z component of the interplanetary magnetic field. Concerning the DDEF, diurnal magnetic oscillations in the horizontal component H of the Earth's magnetic field exhibit a behavior that is opposed to the regular one. These diurnal oscillations are recognized to last several days in all longitudinal sectors. The observational data obtained by all sensors used in the present paper can be interpreted on the basis of existing theoretical models

    Proceedings of the IRI Task Force Activity 1996

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    Consiglio Nazionale delle Ricerche - Biblioteca Centrale -. P.le Aldo Moro, 7, Rome / CNR - Consiglio Nazionale delle RichercheSIGLEITItal

    Comparison of Ionospheric Electron Density Profiles from CHAMP Satellite with NeQuick Model

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    In the summer of 2000 the German geo-research satellite CHAMP was launched into orbit. Its innovative payload arrangement and the low initial orbit allow CHAMP to simultaneously collect and almost continuously analyse precise data relating to gravity and magnetic fields at low altitude. In addition, CHAMP also measures the neutral atmosphere and ionosphere using GPS techniques. Three years after launch, more than 200 CHAMP investigators and co-investigators from all over the world met at the GeoForschungsZentrum in Potsdam to present and discuss the results derived from the extensive data sets of the mission. The main outcome of this expert meeting is summarized in this volume. The book offers a comprehensive insight into the present status of the exploitation of CHAMP data for Earth system research and practical applications in geodesy, geophysics and meteorology

    Electron density and height at the F1 region minimum gradient at low solar activity for an equatorial station

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    Consiglio Nazionale delle Ricerche (CNR). Biblioteca Centrale / CNR - Consiglio Nazionale delle RichercheSIGLEITItal
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