Now showing items 1-20 of 44

    Climatology of the spread F over Roquetes, Spain: Impact of the medium scale traveling ionospheric disturbances 

    Paul, Krishnendu Sekhar; Haralambous, Haris; Altadill Felip, David; Segarra, Antoni; Navas-Portella, Víctor; de Paula Vila, Víctor (Publication date: 2025-11-21)

    Understanding the long-term variability of nighttime Spread F (SF) and its drivers is crucial for improving the knowledge of ionospheric disturbances, which impact radio communication, GNSS positioning, and space weather ...

    Long‐Term Homogeneity of the SSC Series 

    Curto, Juan José; Segarra, Antoni; Torta, Joan Miquel; Marsal, Santiago; Chambodut, Aude; Qvick, Timo; Mursula, Kalevi (Publication date: 2025)

    Geomagnetic storms produce global variations in the geomagnetic field that are measured at magnetic observatories. Roughly one half of magnetic storms are preceded by sudden increases in the horizontal component of the ...

    Assessing Transformer Risk from Geomagnetically Induced Currents in Spain Using Extreme Value Analysis 

    Torta, Joan Miquel; Marsal, Santiago (Publication date: 2025)

    The Lehtinen–Pirjola method modified for efficient modelling of geomagnetically induced currents in multiple voltage levels of a power network 

    Pirjola, Risto; Boteler, David; Tuck, Loughlin; Marsal, Santiago (Publication date: 2022-04-20)

    The need for accurate assessment of the geomagnetic hazard to power systems is driving a requirement to model geomagnetically induced currents (GIC) in multiple voltage levels of a power network. The Lehtinen–Pirjola method ...

    Data‐Driven Transfer Functions From Differential Magnetometer Measurements to Enhance GIC Model Validation Capability: A Case Study in the Spanish Power Grid 

    Marsal, Santiago; Torta, Joan Miquel; Martí, Anna; Hafizi, Raha; Piña-Varas, Perla; Marcuello, Alejandro; Ledo, Juanjo; Curto, Juan José; Queralt, Pilar; cid, Òscar; Ibañez, Miguel (Publication date: 2025-02-16)

    Geomagnetically induced currents (GICs) are unwanted currents flowing in long grounded conductors because of space weather phenomena. Example GICs are those flowing in power transmission lines via grounded transformer ...

    Including the Temporal Dimension in the SECS Technique 

    Marsal, Santiago; Torta, Joan Miquel; Pavón-Carrasco, Francisco Javier; Blake, Sean; Piersanti, Mirko (Publication date: 2020-06-08)

    The equivalent source method of Spherical Elementary Current Systems (SECS) has contributed valuable results for spatial magnetic interpolation purposes where no observations are available, as well as for modeling ...

    Validating GIC Modeling in the Spanish Power Grid by Differential Magnetometry 

    Marsal, Santiago; Torta, Joan Miquel; Curto, Juan José; Cid, Òscar; Ibañez, Miguel; Marcuello, Alejandro (Publication date: 2021-11-12)

    A series of experiences and recommendations are presented concerning the derivation of geomagnetically induced currents (GIC) by use of the differential magnetometry method (DMM) under power lines. This indirect technique, ...

    Pilot Ionosonde Network for Identification of Traveling Ionospheric Disturbances 

    Reinisch, Bodo W.; Galkin, Ivan; Belehaki, Anna; Paznukhov, Vadym; Huang, Xueqin; Altadill Felip, David; Buresova, Dalia; Mielich, Jens; Verhulst, Tobias G. W.; Stankov, Stanimir; Blanch, Estefania; Kouba, Daniel; Hamel, Ryan; Kozlov, Alexander; Tsagouri, Ioanna; Mouzakis, Angelos; Messerotti, Mauro; Parkinson, Murray; Ishii, Mamoru (Publication date: 2018-03-30)

    Traveling ionospheric disturbances (TIDs) are the ionospheric signatures of atmospheric gravity waves. Their identification and tracking is important because the TIDs affect all services that rely on predictable ionospheric ...

    An overview of methodologies for real-time detection, characterisation and tracking of traveling ionospheric disturbances developed in the TechTIDE project 

    Belehaki, Anna; Tsagouri, Ioanna; Altadill Felip, David; Blanch, Estefania; Borries, Claudia; Buresova, Dalia; Chum, Jaroslav; Galkin, Ivan; Juan, José Miguel; Segarra, Antoni; Timoté, Cristhian Camilo; Tziotziou, Kostas; Verhulst, Tobias G. W.; Watermann, Jurgen (Publication date: 2020-09-22)

    The main objective of the TechTIDE project (warning and mitigation technologies for travelling ionospheric disturbances effects) is the development of an identification and tracking system for travelling ionospheric ...

    Improved characterization and modeling of equatorial plasma depletions 

    Blanch, Estefania; Altadill Felip, David; Juan, José Miguel; Camps, Adriano; Basbosa, José; González-Casado, Guillermo; Riba, Jaume; Sanz, Jaume; Vazquez, Gregori; Orús-Pérez, Raúl (Publication date: 2018-08-22)

    This manuscript presents a method to identify the occurrence of Equatorial Plasma Bubbles (EPBs) with data gathered from receivers of Global Navigation Satellite System (GNSS). This method adapts a previously existing ...

    The International Reference Ionosphere Model: A Review and Description of an Ionospheric Benchmark 

    Bilitza, Dieter; Pezzopane, Michael; Truhlik, Vladimir; Altadill Felip, David; Reinisch, Bodo W.; Pignalberi, Alessio (Publication date: 2022-12)

    This paper is a review of the International Reference Ionosphere (IRI) project and model. IRI is recognized as the official standard for the Earth's ionosphere by the International Standardization Organization, the ...

    Multi-instrument detection in Europe of ionospheric disturbances caused by the 15 January 2022 eruption of the Hunga volcano 

    Verhulst, Tobias G. W.; Altadill Felip, David; Barta, Veronika; Belehaki, Anna; Buresova, Dalia; Cesaroni, Claudio; Galkin, Ivan; Guerra, Marco; Ippolito, Alessandro; Herekakis, Themosticles; Kouba, Daniel; Mielich, Jens; Segarra, Antoni; Spogli, Luca; Tsagouri, Ioanna (Publication date: 2022-10-21)

    The 15 January 2022 eruption of the Hunga volcano provides a unique opportunity to study the reaction of the ionosphere to large explosive events. In particular, this event allows us to study the global propagation of ...

    Temporal variation and asymmetry of sunspot and solar plage types from 1930 to 1936 

    Seguí, Aleix; Curto, Juan José; de Paula Vila, Víctor; Rodríguez Gasén, Rosa; Vaquero, José Manuel (Publication date: 2019-02-23)

    Using the recently converted to digital format heliophysics catalogues of the Ebro Observatory published in the 1930s, we analyse simultaneously the temporal variation and asymmetry of two different solar structures located ...

    Modelling by Spherical Cap Harmonic Analysis: A Literature Review 

    Torta, Joan Miquel (Publication date: 2019-11-06)

    There is the need for robust alternatives to the widely used spherical harmonic analysis when measurements are restricted to a region, or when high spatial frequency fields with much less parameters are required. Spherical ...

    Improving the modeling of geomagnetically induced currents in Spain 

    Torta, Joan Miquel; Marcuello, Alejandro; Campanyà, Joan; Marsal, Santiago; Queralt, Pilar; Ledo, Juanjo (Publication date: 2017-04-19)

    Vulnerability assessments of the risk posed by geomagnetically induced currents (GICs) to power transmission grids benefit from accurate knowledge of the geomagnetic field variations at each node of the grid, the Earth’s ...

    The Evolution over Time and North–South Asymmetry of Sunspots and Solar Plages for the Period 1910 to 1937 Using Data from Ebro Catalogues 

    de Paula Vila, Víctor; Curto, Juan José (Publication date: 2020-07-23)

    In this work, we analysed both the evolution over time and the north–south (N-S) asymmetry of certain solar features with regards to their morphological type and area. We examined and compared simultaneously 4212 photospheric ...

    Application of the Markov Chain Model to Sunspots and Solar Plages for the Period 1910 to 1937 Using Data fromEbro Catalogues 

    de Paula Vila, Víctor; Curto, Juan José; Sole, T. (Publication date: 2021-06-11)

    In this article, we analyzed the morphological evolution of the sunspot and solar calcium plage groups recorded at the Ebro Observatory in the period 1910–1937 to make predictions about several properties of these solar ...

    The Solar Rotation in the 1930s from the Sunspot and Flocculi Catalogs of the Ebro Observatory 

    de Paula Vila, Víctor; Curto, Juan José; Casas, Ricard (Publication date: 2016-09-06)

    The tables of sunspot and flocculi heliographic positions included in the catalogs published by the Ebro Observatory in the 1930s have recently been recovered and converted into digital format by using optical character ...

    New Detailed Modeling of GICs in the Spanish Power Transmission Grid 

    Torta, Joan Miquel; Marsal, Santiago; Ledo, Juanjo; Queralt, Pilar; Canillas-Pérez, Victoria; Piña-Varas, Perla; Curto, Juan José; Marcuello, Alejandro; Martí, Anna (Publication date: 2021-07-20)

    The threat of Geomagnetically Induced Currents (GICs) driven by severe Space Weather looms over technological systems such as power grids. Assessing their vulnerability is thus vital to avoid damages or even disruption ...

    Automatic detection of sudden commencements using neural networks 

    Segarra, Antoni; Curto, Juan José (Publication date: 2013-08-23)

    The aim of this work is to develop an automatic system to detect sudden commencements (SCs). SCs are produced by a sudden increase of solar wind dynamic pressure and are detected simultaneously everywhere on the ground ...