Results 51 to 60 of about 1,036 (175)

Characteristics of Post‐Sunset Equatorial Plasma Bubble Occurrences Over Indonesia During a Geomagnetic Storm in August 2024

Journal of Geophysical Research: Space Physics, Volume 131, Issue 7, July 2026.
Abstract We investigated characteristics of post‐sunset equatorial plasma bubbles (EPBs) generated over Indonesia during a geomagnetic storm on 12 August 2024 using Global Navigation Satellite System and ionosonde data. During the August geomagnetic storm, EPBs were generated after sunset over the eastern part of Indonesia (∼120°–130°E) but not over ...
Takuya Sori, Prayitno Abadi, Ihsan Naufal Muafiry, Teguh Nugraha Pratama, Sri Ekawati, Dyah Rahayu Martiningrum, Noersomadi, Edy Maryadi, Febrylian Fahmi Chabibi, Michi Nishioka, Septi Perwitasari, Mamoru Yamamoto   +11 more
wiley   +1 more source

A solar surface dynamo [PDF]

Astronomy & Astrophysics, 2007
Context: Observations indicate that the `quiet' solar photosphere outside active regions contains considerable amounts of magnetic energy and magnetic flux, with mixed polarity on small scales. The origin of this flux is unclear. Aims: We test whether local dynamo action of the near-surface convection (granulation) can generate a significant ...
Vögler, A., Schüssler, M.
openaire   +3 more sources

Global Effect of Long‐Lasting 07–12 October 2024 Geomagnetic Storms During the Transition From a Strong (G3) to a Severe (G4) on the Geomagnetic Field and Ionospheric Parameters Distribution

Space Weather, Volume 24, Issue 7, July 2026.
Abstract This study investigates the co‐evolution of geomagnetic field disturbances with ionospheric parameters and their characteristic latitudinal signatures by conducting a location and time‐dependent analysis of the 07–12 October 2024 events, to fill crucial gaps in understanding the coupled response of the magnetosphere‐ionosphere system. This has
Yekoye Asmare Tariku
wiley   +1 more source

Where is the solar dynamo? [PDF]

Journal of Physics: Conference Series, 2013
In this paper I review results from recent global magnetohydrodynamical numerical simulations of solar convection, as a springboard to address the question "Where is the solar dynamo". I first describe and contrast similarities and differences in the large-scale flows and magnetic fields such simulations can produce, with emphasis on polarity reversals
openaire   +1 more source

Predicting cycle 24 using various dynamo-based tools [PDF]

Annales Geophysicae, 2008
Various dynamo-based techniques have been used to predict the mean solar cycle features, namely the amplitude and the timings of onset and peak. All methods use information from previous cycles, including particularly polar fields, drift-speed of the
M. Dikpati
doaj   +1 more source

The Impact of the May 2024 Geomagnetic Storm on TRISAT Orbital Decay: A TLE‐Based Analysis With a Lifetime Forecast

Space Weather, Volume 24, Issue 7, July 2026.
Abstract The 10–13 May 2024 geomagnetic storm was one of the strongest space‐weather events of Solar Cycle 25 and produced a major expansion of the thermosphere, substantially increasing atmospheric drag on low‐Earth‐orbit spacecraft. In this study, we quantify the storm‐time orbital response of TRISAT, Slovenia's first 3U CubeSat, using publicly ...
N. Kosanič, I. Kramberger
wiley   +1 more source

Connecting mean-field theory with dynamo simulations

Living Reviews in Solar Physics
Mean-field dynamo theory, describing the evolution of large-scale magnetic fields, has been the mainstay of theoretical interpretation of magnetism in astrophysical objects such as the Sun for several decades.
Petri J. Käpylä
doaj   +1 more source

Statistical Properties of Dayside Single‐Crest Structure of the Equatorial Ionization Anomaly Derived From Global Ionospheric Maps

Space Weather, Volume 24, Issue 7, July 2026.
Abstract The classical Equatorial Ionization Anomaly (EIA) is characterized by two separated plasma accumulation regions off the geomagnetic equator and a plasma depletion region in between. Deviations from the typical double‐crest structure, including the single crest and multiple crests, have been observed.
Ping Zhou, Xing Meng, Jiawen Chen, Jiuhou Lei   +3 more
wiley   +1 more source

Impact of Doubled CO2 on the Response of the Mesosphere, Thermosphere, and Ionosphere to the 2008–2009 Sudden Stratospheric Warming

Geophysical Research Letters, Volume 53, Issue 12, 28 June 2026.
Abstract We investigate the impact of the 2008–2009 sudden stratospheric warming (SSW) event on the mesosphere, thermosphere, and ionosphere under conditions of doubled carbon dioxide (CO2). Using the Specified Dynamics Whole Atmosphere Community Climate Model with thermosphere‐ionosphere eXtension model, we perform two simulations for the 2008–2009 ...
Sunil Kumar, Jens Oberheide, B. C. Martinez   +2 more
wiley   +1 more source

Toroidal Magnetic Flux Budget in Mean-field Dynamo Model of Solar Cycles 23 and 24

The Astrophysical Journal
We study the toroidal magnetic flux budget of the axisymmetric part of a data-driven 3D mean-field dynamo model of Solar Cycles 23 and 24. The model simulates the global solar dynamo that includes the effects of the formation and evolution of bipolar ...
Valery V. Pipin, Alexander G. Kosovichev
doaj   +1 more source