Ara es mostren els items 61-80 de 91

    • Observations of the relationship between sprite morphology and in-cloud lightning processes 

      Van der Velde, Oscar Arnoud; Mika, Ágnes; Soula, Serge; Haldoupis, Christos; Neubert, Torsten; Inan, Umran S. (2006-08-04)
      Article
      Accés obert
      [1] During a thunderstorm on 23 July 2003, 15 sprites were captured by a LLTV camera mounted at the observatory on Pic du Midi in the French Pyrénées. Simultaneous observations of cloud-to-ground (CG) and intracloud (IC) ...
    • Observations of Western Mediterranean TLE: LS8000 intracloud lightning and high-speed video 

      Van der Velde, Oscar Arnoud; Montañá Puig, Juan; Romero Durán, David; Soula, Serge; Pineda Rüegg, Nicolau; Bech, Joan; Reglero, V. (2009)
      Comunicació de congrés
      Accés restringit per decisió de l'autor
      Transient luminous events (TLE) are electrical phenomena occurring between the ionosphere and the tops of thunderstorms. First discovered in 1989, the family of TLE now consists of different members: sprites, sprite ...
    • On the classification of self-triggered versus other-triggered lightning flashes 

      Sunjerga, A.; Mostajabi, A.; Pineda Rüegg, Nicolau; Romero Durán, David; Van der Velde, Oscar Arnoud; Montanya, Joan; Azadifar, M.; Rubinstein, M.; Diendorfer, Gergard (Institute of Electrical and Electronics Engineers (IEEE), 2018)
      Text en actes de congrés
      Accés obert
      We present in this paper lightning current measurements and LMA (Lightning Mapping Array) data associated with upward flashes observed at the Sàntis Tower during Summer 2017. The LMA network consists of six stations located ...
    • On the TGF/lightning ratio asymmetry 

      Fabró Tàpia, Ferran; Montañá Puig, Juan; Van der Velde, Oscar Arnoud; Pineda Rüegg, Nicolau; Williams, Earle R. (2019-05-14)
      Article
      Accés obert
      Africa is one of the most productive lightning regions on Earth, yet it has a lower TGF-to-lightning ratio especially compared with Central America. In this paper we have analyzed the global distribution of different ...
    • Polarimetric radar characteristics of lightning initiation and propagating channels 

      Figueras i Ventura, Jordi; Pineda Rüegg, Nicolau; Besic, Nikola; Grazioli, Jacopo; Hering, Alessandro; Van der Velde, Oscar Arnoud; Romero Durán, David; Sunjerga, A.; Mostajabi, A.; Azadifar, M.; Rubinstein, M.; Montañá Puig, Juan; Germann, Urs; Rachidi-Haeri, Farhad (2019-05-27)
      Article
      Accés obert
      In this paper we present an analysis of a large dataset of lightning and polarimetric weather radar data collected in the course of a lightning measurement campaign that took place in the summer of 2017 in the area surrounding ...
    • Potential use of space-based lightning detection in electric power systems 

      Montañá Puig, Juan; López Trujillo, Jesús Alberto; Van der Velde, Oscar Arnoud; Solà de las Fuentes, Glòria; Romero Durán, David; Morales Rodríguez, Carlos Augusto; Visacro, Silverio; Saba, Manuel; Goodman, Steven J.; Williams, Earle R.; Peterson, Michael J.; Pineda, Nicolau; Sousa Arcanjo, Marcelo Augusto; Aranguren Fino, Daniel (2022-12)
      Article
      Accés obert
      Information about lightning activity and its parameters is necessary to design and evaluate the lightning protection of an electrical power system. This information can be obtained from ground-based lightning detection ...
    • Registration of X-rays at 2500 m altitude in association with lightning flashes and thunderstorms 

      Montañá Puig, Juan; Fabró Tàpia, Ferran; Van der Velde, Oscar Arnoud; Romero Durán, David; Solà de las Fuentes, Glòria; Hermoso Costa, Juan Ramón; Soula, Serge; Williams, Earle; Pineda Rüegg, Nicolau (2014)
      Article
      Accés obert
      Electric fields and high-energy radiation of natural lightning measured at close range from a mountaintop tower are discussed. In none of the 12 negative cloud-to-ground upward flashes were X-rays observed. Also no energetic ...
    • Relativistic electron beams above thunderclouds 

      Neubert, Torsten; Pasko, V.P.; Bennet, A. J.; Fullekrug, Martin; Roussel Dupré, Robert; Symbalisty, Eugene M. D.; Colman, J.J.; Chanrion, Olivier; Soula, Serge; Van der Velde, Oscar Arnoud; Odzimek, Anna (2011)
      Article
      Accés obert
      Non-luminous relativistic electron beams above thunderclouds have been detected by the radio signals of low frequency ~ 40–400 kHz which they radiate. The electron beams occur ~ 2–9 ms after positive cloud-to-ground lightning ...
    • Small scale simulation of lightning using vertical wires deployed by drones: on the land and sea peak current asymetry 

      Montañá Puig, Juan; Fontanes Molina, Pol; Arcanjo, Marcelo; Urbani, Michele; Williams, Earle Rolfe; Romero Durán, David; Horta Bernús, Ricard; López Trujillo, Jesús Alberto; Van der Velde, Oscar Arnoud; Pineda Rüegg, Nicolau (2022)
      Text en actes de congrés
      Accés restringit per política de l'editorial
      In this work we simulate lightning by means of vertical wires deployed by a multirotor drone under fair weather conditions. These wires, when isolated from ground, acquire an electric potential by virtue of electrostatic ...
    • Spatio-temporal dimension of lightning flashes based on three-dimensional Lightning Mapping Array 

      López Trujillo, Jesús Alberto; Pineda Rüegg, Nicolau; Montañá Puig, Juan; Van der Velde, Oscar Arnoud; Fabró Tàpia, Ferran; Romero Durán, David (2017-10-15)
      Article
      Accés obert
      3D mapping system like the LMA - Lightning Mapping Array - are a leap forward in lightning observation. LMA measurements has lead to an improvement on the analysis of the fine structure of lightning, allowing to characterize ...
    • Spectroscopy of a mesospheric ghost reveals iron emissions 

      Passas, Maria; Van der Velde, Oscar Arnoud; Gordillo Vázquez, Francisco; Gómez-Martín, Juan Carlos; Sánchez, Justo; Pérez Invernón, Francisco José; Sánchez-Ramírez, Rubén; García Comas, Maia; Montañá Puig, Juan (2023-12-12)
      Article
      Accés obert
      Mesospheric Green emissions from excited Oxygen in Sprite Tops (ghosts) are infrequent and faint greenish transient luminous events that remain for hundreds of milliseconds on top of certain energetic sprites. The main ...
    • Sprites and elves as proxy of energetic lightning flashes in winter: what can we learn from mesospheric discharges for the protection of wind turbines? 

      Montañá Puig, Juan; Fabró Tàpia, Ferran; Van der Velde, Oscar Arnoud; Hermoso, Blas (2011)
      Text en actes de congrés
      Accés obert
      Sprites and Elves are commonly observed in Europe, especially also in winter maritime storms. It is well known that sprites are related to large electric charge positive flashes and elves are related with high amplitude ...
    • Statistics and variability of the altitude of elves 

      Van der Velde, Oscar Arnoud; Montañá Puig, Juan (2016-05-07)
      Article
      Accés obert
      From June 2008 to January 2016 nearly 800 elves have been recorded by a low-light camera in northeastern Spain. Elves occur in this region mainly over the lower-topped cold airmass maritime thunderstorms, peaking from ...
    • Study of the total lightning activity in a hailstorm 

      Montañá Puig, Juan; Soula, Serge; Pineda Rüegg, Nicolau; Van der Velde, Oscar Arnoud; Clapers, Pere; Solà de las Fuentes, Glòria; Bech, Joan; Romero Durán, David (2007)
      Comunicació de congrés
      Accés restringit per decisió de l'autor
      A thunderstorm which developed in North-Eastern region of Spain on 16th June, 2006 is analyzed. This thunderstorm could be severe because it produced hailstones larger than 19 mm. The cell life time was 3h 30 minutes. ...
    • Study of the total lightning activity in a hailstorm 

      Montañá Puig, Juan; Soula, Serge; Pineda, Nicolau; Van der Velde, Oscar Arnoud; Clapers, Pere; Solà de las Fuentes, Glòria; Bech, Joan; Romero Durán, David (2009)
      Article
      Accés restringit per decisió de l'autor
      A thunderstorm that developed over northeastern Spain on 16 June 2006 is analyzed. This severe thunderstorm produced hailstones as large as 40 mm and had a lifetime of 3 h and 30 min. Radar cross-sections show strong ...
    • Temporal and spatial evolution of intracloud lightning associated ith sprite-producing positive cloud-to-ground flashes in Northeastern Spain 

      Van der Velde, Oscar Arnoud; Montañá Puig, Juan; Soula, Serge; Pineda Rüegg, Nicolau; Chanrion, Olivier (2009)
      Comunicació de congrés
      Accés restringit per decisió de l'autor
    • The start of lightning: evidence of bidirectional lightning initiation 

      Montañá Puig, Juan; Van der Velde, Oscar Arnoud; Williams, Earle R. (Macmillan Publishers, 2015-10-18)
      Article
      Accés obert
      Lightning flashes are known to initiate in regions of strong electric fields inside thunderstorms, between layers of positively and negatively charged precipitation particles. For that reason, lightning inception is ...
    • Thunderstorm characteristics favouring downward and upward lightning to wind turbines 

      Pineda, Nicolau; Montañá Puig, Juan; Salvador Yuste, Albert; Van der Velde, Oscar Arnoud; López Trujillo, Jesús Alberto (2018-12-01)
      Article
      Accés obert
      Meteorological conditions and thunderstorm characteristics related to lightning threats to wind turbines are discussed in this paper. Due to the rotating blades, wind turbines may be regarded peculiar tall objects, more ...
    • Time and space correlation between sprites and their parent lightning flashes for a thunderstorm observed during the HyMeX campaign 

      Soula, Serge; Defer, E.; Fullekrug, Martin; Van der Velde, Oscar Arnoud; Montañá Puig, Juan; Bousquet, O.; Mlynarczyk, Janusz; Coquillat, S.; Pinty, J.P.; Rison, William; Krehbiel, P.; Thomas, R.; Pedeboy, S. (American Geophysical Union (AGU), 2015-11-27)
      Article
      Accés obert
    • Total lightning analysis of a tornadic severe weather event 

      Pineda Rüegg, Nicolau; Bech, Joan; Rigo, Tomeu; Montañá Puig, Juan; Van der Velde, Oscar Arnoud (2009)
      Comunicació de congrés
      Accés restringit per decisió de l'autor
      This study presents an analysis of total lightning and radar data of a severe weather event that took place in the early morning of 2nd November 2008 in Catalonia (NE Spain). A general overview of the synoptic framework ...