Articles | Volume 16, issue 2
https://doi.org/10.5194/hgss-16-13-2025
© Author(s) 2025. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/hgss-16-13-2025
© Author(s) 2025. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Aurora records in the Spanish newspaper Extremadura for the period 1923–2017
Constantino Sánchez Romero
Departamento de Física, Universidad de Extremadura, 06006 Badajoz, Spain
Lucía Díaz-Condiño
Departamento de Física, Universidad de Extremadura, 06006 Badajoz, Spain
Irene Tovar Hernández
Departamento de Física, Universidad de Extremadura, 06006 Badajoz, Spain
Alejandro Jesús Pérez Aparicio
Departamento de Física, Universidad de Extremadura, 06006 Badajoz, Spain
Instituto Universitario de Investigación del Agua, Cambio Climático y Sostenibilidad (IACYS), Universidad de Extremadura, 06006 Badajoz, Spain
Earth Remote Sensing Laboratory (EaRSLab) and Center for Sci-Tech Research in EArth sysTem and Energy-CREATE, Instituto de Investigação e Formação Avançada (IIFA), Universidade de Évora, 7000-671 Évora, Portugal
Víctor Manuel Sánchez Carrasco
CORRESPONDING AUTHOR
Departamento de Física, Universidad de Extremadura, 06006 Badajoz, Spain
Instituto Universitario de Investigación del Agua, Cambio Climático y Sostenibilidad (IACYS), Universidad de Extremadura, 06006 Badajoz, Spain
María Cruz Gallego Herrezuelo
Departamento de Física, Universidad de Extremadura, 06006 Badajoz, Spain
Instituto Universitario de Investigación del Agua, Cambio Climático y Sostenibilidad (IACYS), Universidad de Extremadura, 06006 Badajoz, Spain
Departamento de Física, Universidad de Extremadura, 06006 Badajoz, Spain
Instituto Universitario de Investigación del Agua, Cambio Climático y Sostenibilidad (IACYS), Universidad de Extremadura, 06006 Badajoz, Spain
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Maite deCastro, José González-Cao, Nicolás G. deCastro, Juan J. Taboada, José M. Vaquero, and Moncho Gómez-Gesteira
Clim. Past, 21, 593–607, https://doi.org/10.5194/cp-21-593-2025, https://doi.org/10.5194/cp-21-593-2025, 2025
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Persistent rains in the eastern Atlantic during 1768–1769 caused the worst agricultural crisis in Galicia and northern Portugal. Using the EKF400v2 paleo-reanalysis dataset, it was found that the rainfall anomaly was positive in 11 out of 12 months. June 1768 saw the highest positive rain anomaly of the century; September 1768 saw the second-highest. The atmospheric synoptic patterns show negative anomalies in sea level pressure and 500 hPa. These patterns induce surface low-pressure systems.
Francisco Javier Acero, Manuel Antón, Alejandro Jesús Pérez Aparicio, Nieves Bravo-Paredes, Víctor Manuel Sánchez Carrasco, María Cruz Gallego, José Agustín García, Marcelino Núñez, Irene Tovar, Javier Vaquero-Martínez, and José Manuel Vaquero
Nat. Hazards Earth Syst. Sci., 25, 305–320, https://doi.org/10.5194/nhess-25-305-2025, https://doi.org/10.5194/nhess-25-305-2025, 2025
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The month of June 1925 was found to be exceptional in the southwest interior of the Iberian Peninsula due to the large number of thunderstorms and their significant impacts, with serious losses of human lives and material resources. We analyzed this event from different, complementary perspectives: reconstruction of the history of the events from newspapers, study of monthly meteorological variables of the longest series available, and the analysis of the meteorological synoptic situation.
Nieves Bravo-Paredes, María Cruz Gallego, Ricardo M. Trigo, and José Manuel Vaquero
Clim. Past, 19, 1397–1408, https://doi.org/10.5194/cp-19-1397-2023, https://doi.org/10.5194/cp-19-1397-2023, 2023
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We present the earliest records made in San Fernando, very close to Cádiz (SW Spain). Several previous works have already recovered a significant number of meteorological records of interest in these localities. However, more than 40 000 daily meteorological observations recorded at the Royal Observatory of the Spanish Navy (located in San Fernando) were previously unnoticed and remained neither digitized nor studied. We analyze in detail these newly recovered meteorological readings.
Víctor M. S. Carrasco, Enric Aragonès, Jorge Ordaz, and José M. Vaquero
Hist. Geo Space. Sci., 9, 133–139, https://doi.org/10.5194/hgss-9-133-2018, https://doi.org/10.5194/hgss-9-133-2018, 2018
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An analysis is made of the records made by Spanish observers of a notable aurora on 18 January 1770 in order to study the characteristics of this event. The records indicate that the phenomenon was observed in both continental and insular territories of Spain. In general, observers described the aurora as red in colour, from sunset to midnight. Calculations of the geomagnetic latitudes of the observation locations indicate this aurora was observed over a wide range of abnormally low latitudes.
Hisashi Hayakawa, José M. Vaquero, and Yusuke Ebihara
Ann. Geophys., 36, 1153–1160, https://doi.org/10.5194/angeo-36-1153-2018, https://doi.org/10.5194/angeo-36-1153-2018, 2018
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A record has been found of an "aurora" observed on 27 October 1856 in the Philippines, practically at the magnetic equator. An analysis of this report indicates that it could belong to a "sporadic aurora" because of low magnetic activity at that time. We provide a possible physical mechanism that could explain the appearance of this sporadic, low-latitude aurora, according to the analyses on the observational report and magnetic observations at that time.
José M. Vaquero
Hist. Geo Space. Sci., 8, 53–56, https://doi.org/10.5194/hgss-8-53-2017, https://doi.org/10.5194/hgss-8-53-2017, 2017
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An analysis is given of the account of a
globe of fireobserved in Zafra (Spain) in the middle of the 16th century. During a strong storm, Conde Don Pedro observed what he described as a
globe of firethat was directed against the city and abruptly changed course. He attributed the change in course to a miracle. He described neither any damage nor sound.
S. Pereira, A. M. Ramos, J. L. Zêzere, R. M. Trigo, and J. M. Vaquero
Nat. Hazards Earth Syst. Sci., 16, 371–390, https://doi.org/10.5194/nhess-16-371-2016, https://doi.org/10.5194/nhess-16-371-2016, 2016
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This work explores the meteorological conditions of the hydro-geomorphologic event of December 1909 that triggered the highest floods in more than 100 years at the Douro river's mouth and caused important social impacts over the Portuguese and Spanish territories.
The study of this extreme event contributes to a comprehensive and systematic synoptic evaluation of the second most deadly hydro-geomorphologic disaster event occurred in Portugal since 1865.
Related subject area
Research History: External Geophysics (Atmosphere, Ionosphere, Magnetosphere, Aurora)
Lightning and thunder explanations in encyclopedias – from ancient Greece to Wikipedia
Conjugate aurora observations by the Gjøa and Discovery expeditions
Observations of mesospheric clouds in Latvia 1957–1983
The early meteorological network of the Societas Meteorologica Palatina (1781–1792): foundation, organization, and reception
History of EISCAT – Part 6: the participation of Japan in the EISCAT Scientific Association
A pioneering time of discoveries in large-scale tropical meteorology: 1960 through 1972
History of the Tromsø ionosphere heating facility
History of EISCAT – Part 5: Operation and development of the system during the first 2 decades
Kristian Schlegel
Hist. Geo Space. Sci., 15, 71–80, https://doi.org/10.5194/hgss-15-71-2024, https://doi.org/10.5194/hgss-15-71-2024, 2024
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The explanation of thunder and lightning in encyclopedias from ancient times to Wikipedia is described and discussed.
Alv Egeland
Hist. Geo Space. Sci., 15, 27–39, https://doi.org/10.5194/hgss-15-27-2024, https://doi.org/10.5194/hgss-15-27-2024, 2024
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During the Gjøa and Discovery expeditions (1901–1906), weak geomagnetic signatures were observed simultaneously with visual polar cap auroras. Main types are transpolar arcs, poleward-moving substorm arcs, and Sun-aligned arcs. The first two are infrequent, while the last one occurs often. They appear like the regular magnetic solar Sq variation. It is suggested that they are embedded in polar rain and dependent on the density and energy of photoelectrons.
Jānis Kauliņš
Hist. Geo Space. Sci. Discuss., https://doi.org/10.5194/hgss-2024-10, https://doi.org/10.5194/hgss-2024-10, 2024
Revised manuscript accepted for HGSS
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Long-term series of historical observations in Latvia of mesospheric clouds are digitized. Observational data are freely available to researchers. Observation sites, methodology and technical support are described. A brief overview of mesospheric cloud observation statistics 1957–1983.
Peter Winkler
Hist. Geo Space. Sci., 14, 93–120, https://doi.org/10.5194/hgss-14-93-2023, https://doi.org/10.5194/hgss-14-93-2023, 2023
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The foundation of the Societas Meteorologica Palatina was the most important step toward a physical consideration of meteorology. The organization was exemplary for later observational networks. The data were printed in 12 volumes of ephemerides, being for a long time the most important and reliable database for scientific research. This data pool is not only of historical interest, but it is also used in modern research in many fields.
Nobuo Matuura, Ryoichi Fujii, and Satonori Nozawa
Hist. Geo Space. Sci., 14, 61–69, https://doi.org/10.5194/hgss-14-61-2023, https://doi.org/10.5194/hgss-14-61-2023, 2023
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This paper describes the details of the Japan's participation in the EISCAT Radar Scientific Association as the 7th associate country approved in 1995, emphasizing strong collaboration with Norwegian scientists and the EISCAT Radar Scientific Association towards the realization of the Svalbard second antenna. Also described is a brief summary of Japanese EISCAT-related scientific achievement, comprehensive scientific collaborations so far between Japan and Europe, and hopes for EISCAT_3D.
Roland A. Madden
Hist. Geo Space. Sci., 14, 33–41, https://doi.org/10.5194/hgss-14-33-2023, https://doi.org/10.5194/hgss-14-33-2023, 2023
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The Madden–Julian Oscillation (MJO) is an important phenomenon in tropical meteorology first discovered in the early 1970s by Roland Madden and Paul Julian. In this paper, Roland Madden relates the story of developments in theory, observations, and analysis techniques in the 1960s that led to that discovery.
Michael T. Rietveld and Peter Stubbe
Hist. Geo Space. Sci., 13, 71–82, https://doi.org/10.5194/hgss-13-71-2022, https://doi.org/10.5194/hgss-13-71-2022, 2022
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We present the history of how and why a high-power radio wave transmitter facility with large antenna arrays was built in northern Norway in the 1970s with the aim of injecting radio waves into the auroral ionosphere. The facility has conducted fundamental research on plasmas, by heating electrons and exciting plasma waves in the ionosphere; the effects of these experiments have been measured using a host of other instruments, such as incoherent scatter radars, radio receivers, and cameras.
Gudmund Wannberg
Hist. Geo Space. Sci., 13, 1–21, https://doi.org/10.5194/hgss-13-1-2022, https://doi.org/10.5194/hgss-13-1-2022, 2022
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EISCAT, the European Incoherent SCATter system, was an advanced research radar system established in northern Scandinavia in the mid-1970s for studies of the aurora and the earth's plasma environment. This paper describes the operation, development, problems and successes of the system during its first 2 decades, as recalled by its former deputy director.
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Short summary
This article collects and analyzes reports of auroras published in the Extremadura newspaper from 1923 to 2017. We identified 31 news items describing these events, including major auroras in 1926, 1938, 1957, and 1991. This research highlights the value of newspapers in reconstructing past solar activity.
This article collects and analyzes reports of auroras published in the Extremadura newspaper...