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Automatic Detection of Large-Scale Traveling Ionospheric Disturbances Using GNSS Data and Image Processing Techniques
No full textLarge-scale traveling ionospheric disturbances (LSTIDs) are wave-like structures propagating through the ionosphere from auroral to lower latitudes, affecting radar-based technologies and satellite navigation. Due to their disruptive effects, timely detection is crucial. This work presents an autonomous detection technique based on travel-time diagrams of detrended Total Electron Content (TEC). Our method employs a network of GNSS receivers across Europe, selected using a K-Means clustering algorithm to ensure comprehensive spatial coverage. Applying image processing techniques, we identify propagating features of positive and negative amplitude in detrended TEC keograms. These features are fitted using the RANdom SAmple Consensus method to estimate propagation speed along the North-South direction. Following feature identification, we refine our results by merging positive and negative perturbations and filtering out false positives based on physical constraints. This methodology allowed us to compile a catalog of LSTID with periods ranging from 30 to 90 min, spanning 2021-2024. To validate our approach, we conducted case studies and statistical analyses, confirming accuracy and reliability. Additionally, testing in North America and Japan demonstrated the algorithm broader applicability. Our findings, obtained with user-defined parameters tailored to examine LSTIDs with periodicities in the 30-90 min range, show an average speed of 629 ± 215 m/s and period of 62 ± 14 min. A direct relation with auroral electrojet indices confirms that stronger auroral currents produce faster, higher amplitude and shorter period LSTIDs. Furthermore, our analysis reveals a link between LSTID occurrences and geomagnetic activity, reinforcing previous findings. Plain Language Summary Large Scale Traveling Ionospheric Disturbances (LSTIDs) are wave-like disturbances in the Earth's upper atmosphere that can disrupt GPS and communication systems. They are mainly caused by solar storms and geomagnetic activity, making their detection crucial for space weather monitoring. This study presents an automated technique to detect LSTIDs using data from GNSS receivers. By analyzing variations in Total Electron Content, we identify LSTIDs through image processing and machine learning techniques. Our method was applied to 2021-2024 data, showing that using user-defined parameters tailored to reproduce previous findings our LSTIDs results in Europe show an average speed of 629 m/s and a period of around one hour. We highlight a strong direct relation between LSTID activity and geomagnetic storms, confirming that intense auroral currents generate faster and more energetic disturbances. Testing on one case event in the United States and Japan demonstrated that the method is reliable across different regions. This fully automated approach improves ionospheric monitoring and could be integrated into real-time space weather forecasting, helping mitigate the effects of ionospheric disturbances on satellite and radar-based technologies.PublishedJCR Journa
Evaluation of Trimble Centerpoint RTX correction service for real-time GNSS monitoring: a field-based comparison with RTK positioning
No full textNowadays, real-time geodetic monitoring has applications in a wide range of areas in the geosciences and beyond, such as monitoring active volcanoes and critical engineering structures, and developing early warning systems for earthquakes, tsunamis and landslides. This study evaluates the effectiveness of Trimble Inc.'s patented CenterPoint Real Time eXtended (RTX) Global Navigation Satellite System (GNSS) correction service through a comparative analysis with the traditional singlebaseline Real-Time Kinematics (RTK) approach, using a series of field tests. The tests were specifically designed to assess the applicability of the RTX technique for real-time geodetic monitoring of seismic and volcanic active areas or landslides, and engineering structures, with a focus on the amplitude and rate of displacement. A geodetic GNSS antenna was connected to two receivers operating in RTX and RTK modes. A micrometric sled and a telescopic rod were used to induce 3D controlled displacements of the antenna. A total of 108 measurement sessions were collected, resulting in 286,116 one-second observations. The performance of the RTX and RTK methodologies was assessed in terms of precision and accuracy using various statistical metrics. The RTX service consistently demonstrated performance that was either competitive with or superior to RTK, particularly for vertical displacements ( 1.5 cm for RTK) and rapid deformation scenarios, where precision and accuracy errors remained within a few centimetres. Our field tests demonstrate the reliability and robustness of the RTX technique for precise real-time displacement monitoring, potentially paving the way for its application in geohazard mitigation.PublishedJCR Journa
Corrigendum to "Chemical variability in volcanic gas plumes and fumaroles along the East African Rift System: New insights from the Western Branch" [Chemical Geology 596 (2022) 120811]
No full textPublishedJCR Journa
Geomorphological Evidence of Ice Activity on Mars Surface at Mid-Latitudes
No full textNumerose indagini basate su radar, osservazioni spettrali, modelli geomorfologici e paleoclimatici supportano su Marte la presenza di ghiaccio al suolo anche a latitudini medio-basse. La presenza di ghiaccio e strutture glaciali in prossimità della superficie è stata ipotizzata presso Ismenius Lacus, ma la composizione e l'età del ghiaccio rimangono indeterminate. La nostra analisi stereoscopica ad alta risoluzione rivela particolari e distintive caratteristiche morfologiche indicative di deformazione plastica glaciale. Tra queste, poliedri a spigoli vivi, strutture a chevron e fratture beanti en-echelon. Le attuali condizioni climatiche potrebbero supportare la stabilità del ghiaccio durante tutto l'anno, mentre poliedri a spigoli vivi, fratture aperte e l'assenza di crateri sovrapposti suggeriscono una glaciazione attiva. Il sistema deltizio dell'Ariguani non presenta in realtà dei caratteri fluviali ma è coerente con i processi di erosione e deposizione glaciale. A differenza dei ghiacciai terrestri, l'accumulo di ghiaccio qui è probabilmente alimentato dalla scarpata a causa della fusione stagionale del permafrost sotto la pressione litostatica. Questo processo può generare flussi neoglaciali che alimentano una lingua glaciale. Questo meccanismo può anche spiegare altre caratteristiche regionali, tra cui la subsidenza delle valli a U, le frane gravitazionali, il flusso lobato di materiale a bassa viscosità e i crateri a forma di anello. Pertanto, proponiamo i poliedri a spigoli vivi come marcatori diagnostici per identificare dinamiche glaciali attualmente in corso su Marte, consentendo in futuro il rilevamento automatico di ambienti glaciali attivi.Extensive radar investigations, observed spectral signatures, geomorphological, and paleoclimate modeling support the presence of mid- to low-latitude ground ice on Mars. The presence of near-surface ice and glacial features has been proposed in Ismenius Lacus, but the ice composition and age remain unconstrained. Our high-resolution stereoscopic analysis reveals distinctive landforms, including sharp-edged polyhedra, chevron patterns, and en-echelon open fractures, indicative of plastic glacial deformation. Current climatic conditions may support year-round ice stability, while sharp-edged polyhedra, open fractures, and the absence of superposed craters suggest active glaciation. The Ariguani delta system lacks fluvial signatures but aligns with glacial erosional and depositional processes. Unlike terrestrial glaciers, ice accumulation here is likely driven by escarpment-fed melt from seasonal permafrost thawing under lithostatic pressure, generating neo-glacial flows that sustain the glacial tongue. This mechanism can also explain regional features, including U-shaped valley subsidence, gravitational slides, flow of low-viscosity material lobes, and ring-mold craters. Thus, we propose sharp-edged polyhedra as diagnostic markers for identifying ongoing ice dynamics on Mars, enabling future automated detection of active glacial environments.PublishedOSA3: Climatologia e meteorologia spazialeJCR Journa
COURSE: Cross-scale cOUpling pRocesses in the Solar–tErrestrial system—SCOSTEP’s new program for 2026–2030
No full textPublishedJCR Journa
Italian research and development in space weather and space climate: a state-of-the-art overview
No full textThis article presents a concise overview of research developments and advancements in space weather and space climate, with a specific focus on the significant contributions made by members of the Italian Space Weather Community (SWICo). We highlight their achievements in instrument development, observational techniques, and modeling. Furthermore, we introduce a special collection of papers within this journal, entitled "Frontiers in Italian Studies on Space Weather and Space Climate." This collection features a selection of research articles and presentations from the Second and Third SWICo Congresses, held in Rome in February 2022 and November 2024, respectively, and hosted by the Italian Space Agency.PublishedJCR Journa
Midnight Simultaneous Observations of Spread‐F and Multiple F‐Layer Stratifications During the 11–12 May 2024 Geomagnetic Superstorm
No full textA geomagnetic superstorm occurred from May 10 to 12, 2024, producing significant spatial and
temporal disturbances in the ionosphere. Ground‐based ionosonde and GPS‐TEC data enabled the
identification, analysis, and possible interpretation of a unique event: the simultaneous occurrence of Spread‐F
and multiple F‐layer stratifications during the local midnight hours of May 11. To the best of our knowledge,
this is the first documented case of such a phenomenon occurring at local midnight. This study provides new
insights into the dynamics of the equatorial and low‐latitude ionosphere under extreme geomagnetic conditions
and highlights the critical role of coordinated, multi‐instrument observations in advancing our understanding of
ionospheric electrodynamics.PublishedOSA3: Climatologia e meteorologia spazialeJCR Journa
Seismically induced fault leakage from the Val d'Agri hydrocarbon reservoir (Southern Italy)
No full textThis indicates that temporary seal breaches occurred naturally in the geological past (earlier than oil extraction), likely due to fault-valve action during strong earthquakes. Hydrogeochemical analyses of groundwater indicate that the San Giovanni spring, located near productive oil wells, exhibits negative δ 34 S(SO 4) (− 14.20 ‰) and δ 13 C deep (− 11.8 ‰) values, along with a high CO 2 concentration (5.4 mmol/L). These results indicate methane oxidation in the San Giovanni spring, related to long-term mixing between hydrocarbons, likely released during strong seismic events, and meteoric fluids. These findings highlight the importance of reconstructing preproduction processes to assess environmental hazards more effectively, particularly in seismically active, hydrocarbon-rich regions such as the Val d'Agri Basin.PublishedJCR Journa
Evaluating the effectiveness of quantitative descriptions of Earth Science phenomena during outreach activities
No full textWe present a study aimed at evaluating how
experiment-driven communication, in particular in the field
of volcanology, seismology and tsunami sciences, is effective
in conveying quantitative concepts and increasing the under-
standing of natural phenomena. We conducted two dissem-
ination initiatives dedicated to creating the general public’s
awareness and appreciation of geoscience, each targeting a
different type of audience. The first initiative was a lesson
delivered to high-school students with a humanistic back-
ground as part of the European Researchers’ Night. The sec-
ond was an interactive experiment/activity carried out in a
booth hosted by the Italian Civil Protection Department, fo-
cused on best practices for risk mitigation. It was presented
during an international event dedicated to fandom culture
(Lucca Comics and Games), which was entirely unrelated
to geoscience. The core of both initiatives – focused on vol-
canic conduit dynamics, earthquake localization and magni-
tude calculation, and volcanic landslide-induced tsunami –
consisted of hands-on experiments, corroborated by the de-
termination of parameter values, adding a quantitative di-
mension to the phenomenological experience. We also de-
livered questionnaires to all participants aimed at evaluat-
ing the effectiveness of the conveyed messages. One ques-
tionnaire was delivered to the 62 high-school students dur-
ing the European Researchers’ Night and two questionnaires
(pre- and post-experiment) were delivered to 26 participants
during Lucca Comics and Games. The results of the survey
show that our experiments were well-received and, as a gen-
eral conclusion, underline that geophysical hands-on experi-
ences can successfully foster the engagement of people, even
when providing quantitative evidence. However, it is also
important to adapt the dissemination initiative to the target
audience, by considering the amount of time available and
the background of the attendee. For external instructors who
present experiments to high school classes, we once again as-
sessed the importance of the synergy between school teach-
ers and external communicators before and after the events,
in order to avoid contradictory messages delivered to stu-
dents. We finally underline the importance of finding new
ways to promote a modern and interactive way to communi-
cate geosciencePublishedJCR Journa
Fabrication of new glass-ceramic materials from float glass and slag waste by modulation of the cooling rate
No full textThis study explores an alternative route to recycle waste materials from float glass (FG, 30 wt%) and copper slag (CS, 70 wt%). The FG is a silica-rich glass, while the CS is rich in Fe and Zn. They were melted at 1550 • C to obtain a homogeneous glass that was then re-melted and cooled at 10 (low) and 500 (high) • C/h to produce a glass-ceramic. X-Ray Powder Diffraction, Scanning Electron Microscope and Electron microprobe characterisations show that both products contain spinel crystals within an abundant glassy matrix. At 500 • C/h, unexpectedly, the glass-ceramic contains a higher content (30.0 ± 5.5 area%) of tiny and long dendrites (spinifex) of spinels than at 10 • C/h (13.7 ± 2.2 area%); at the low rate, spinels are skeletal (large crystals) to dendritic (tiny and short) and larger than at high rate. This unveils that the estimated crystal growth rate (10 − 7 cm/s) is higher at 500 • C/h. The crystal-chemistry of spinels results in more enriched Fe and Zn at 10 • C/h than at the high rate. This approach is promising for various applications or for concentrating valuable transition metals (Fe, Zn) as a function of cooling rate and type and quantity of starting waste materials; also, it avoids treatments with additives or fluxing agents and it provides, thanks to the dielectric properties shown, a strong potential for industrial use as a microwave absorber.PublishedJCR Journa