Lucilla Alfonsi's research while affiliated with National Institute of Geophysics and Volcanology and other places

Publications (14)

Article
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The Antarctic and Arctic regions are Earth's open windows to outer space. They provide unique opportunities for investigating the troposphere–thermosphere–ionosphere–plasmasphere system at high latitudes, which is not as well understood as the mid- and low-latitude regions mainly due to the paucity of experimental observations. In addition, differe...
Article
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Swarm is the first European Space Agency (ESA) constellation mission for Earth Observation. Three identical Swarm satellites were launched into near-polar orbits on 22 November 2013. Each satellite hosts a range of instruments, including a Langmuir probe, GPS receivers, and magnetometers, from which the ionospheric plasma can be sampled and current...
Article
We investigate the response of the topside ionosphere, auroral and polar sectors, to the forcing of the geospace during September 2017. Specifically, we aim at characterizing such a response in terms of the involved spatial scales and of their intensification during the different auroral and polar cap activity conditions experienced in the selected...
Article
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In this study, we investigate the negative ionospheric response over the European sector during two storms that took place on 8 September 2017, primarily, by exploiting observations over ten European locations. The spatial and temporal variations of TEC, foF2 and hmF2 ionospheric characteristics are examined with the aim to explain the physical mec...
Article
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In this work we address the following question: can we use modern, cutting edge techniques conceived for the analysis of nonlinear non-stationary signals to measure scale-wise lags? To this scope, we propose a novel technique, called Intrinsic Mode Cross Correlation method, which leverages on the decomposition of nonlinear non-stationary signals by...
Article
We estimate the zonal drift velocity of small-scale ionospheric irregularities at low latitude by leveraging the spaced-receivers technique applied to two GNSS receivers for scintillation monitoring installed along the magnetic parallel passing in Presidente Prudente (Brazil, magnetic latitude 12.8°S). The investigated ionospheric sector is ideal t...
Article
Full-text available
The storm onset on 7 September 2017, triggered several variations in the ionospheric electron density, causing severe phase fluctuations at polar latitudes in both hemispheres. In addition, although quite rare at high latitudes, clear amplitude scintillations were recorded by two Global Navigation Satellite System receivers during the main phase of...
Article
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We aim at contributing to the reliability of the phase scintillation index on Global Navigation Satellite System (GNSS) signals at high-latitude. To the scope, we leverage on a recently introduced detrending scheme based on the signal decomposition provided by the fast iterative filtering (FIF) technique. This detrending scheme has been demonstrate...
Article
Full-text available
We contribute to the debate on the identification of phase scintillation induced by the ionosphere on the global navigation satellite system (GNSS) by introducing a phase detrending method able to provide realistic values of the phase scintillation index at high latitude. It is based on the fast iterative filtering signal decomposition technique, w...
Article
Full-text available
The paper presents an unprecedented description of the climatology of ionospheric irregularities over the Arctic derived from the longest Global Navigation Satellite Systems data series ever collected for this specific aim. Two TEC and scintillation receivers are working at Ny-Ålesund (Svalbard, NO), the first of which has been installed in late Se...
Article
Full-text available
We introduce a new information and communication technology (ICT) cloud-based architecture for Global Navigation Satellite System (GNSS) high-accuracy solutions, offering also a commercial overview of GNSS downstream market to show how the developed innovation is thought to fit in the real context. The designed architecture is featured by dynamic s...

Citations

... [28,[36][37][38][39][40][73][74][75][76]. The mathematical analysis of the IF method [36,[41][42][43][44][70][71][72] allows both to guarantee a priori its convergence and to accelerate the algorithm via the Fast Fourier Transform producing the aforementioned FIF technique [41,44]. ...
... The zonal drift velocity at low latitudes using the spaced receiver technique applied to two GNSS receivers installed at Presidente Prudente, Brazil during September 2003 and February 2004. The hourly average zonal drift velocities peaked after sunset and gradually declined in the following hours [5]. The zonal drift velocity is calculated using three single-frequency GPS receivers at the equatorial atmospheric radar facility in Kototabang, Indonesia. ...
... Indeed, some recent papers support the definition of scintillations as due to the sole diffractive (stochastic) effects, claiming that the deterministic contribution to the refractive effects can be mitigated through an adaptive choice of the cut-off frequency. Such a choice would lead to a reduction in the "phasewithout-amplitude scintillation occurrence" (Mushini et al. 2012 Ghobadi et al. (2020) and by Spogli et al. (2021). To assess the scintillations climate, the challenge is to find the "best" cut-off frequency to filter long-term (years) data series. ...
... Indeed, some recent papers support the definition of scintillations as due to the sole diffractive (stochastic) effects, claiming that the deterministic contribution to the refractive effects can be mitigated through an adaptive choice of the cut-off frequency. Such a choice would lead to a reduction in the "phasewithout-amplitude scintillation occurrence" (Mushini et al. 2012 Ghobadi et al. (2020) and by Spogli et al. (2021). To assess the scintillations climate, the challenge is to find the "best" cut-off frequency to filter long-term (years) data series. ...
... Due to the importance of ionospheric scintillation in space weather application, a lot of research works have been carried out on the modeling of ionospheric scintillations (e.g., Grzesiak et al., 2018;Materassi et al., 2020;Priyadarshi, 2015;Rezende et al., 2010;Spogli, Alfonsi, Romano, et al., 2013). de Lima et al. (2015) used the data obtained at São Luís, Brazil together with the neural network technique to build prediction model of ionospheric scintillation. ...
... To assess the scintillations climate, the challenge is to find the "best" cut-off frequency to filter long-term (years) data series. De Franceschi et al. (2019) have demonstrated that this is not an easy task. For scintillation derived from GNSS ionospheric data suitable metrics and even a univocal definition of scintillation have not yet been agreed upon by researchers in the field. ...
... Further studies are needed for the statistical assessment of our results which can enable real-time implementation of the proposed detrending scheme in the next generation of scintillation receivers and dedicated infrastructures [24]. In addition, the technique can be also used on shorter time windows (e.g., 10 s) to account for shorter variations that are driven by sudden events or occurring in the high-latitude ionosphere (see [25], [26]). ...