Correspondence between the ULF wave power spatial distribution and auroral oval boundaries

Козырева, О. В.; Пилипенко, В. А.; Pilipenko, Vyacheslav; Engebretson, M. J.; Климушкин, Дмитрий; Klimushkin, D. Yu.; Mager, P. N.

doi:10.12737/20999

Cited by 6 publications

(6 citation statements)

References 31 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…This paper studies ULF power in solar wind and on ground over monthly and solar cycle time scales. Ground ULF waves in Pc5 frequency range are known to be driven predominantly by solar wind speed (Tanskanen et al, 2005) and to be related to the Kelvin-Helmholtz mechanism (Nykyri, 2013) and auroral substorm processes (Pilipenko et al, 2001;Kozyreva et al, 2016). ULF waves on ground as well as in solar wind have been examined for decades (Jacobs et al, 1964).…”

Section: Discussionmentioning

confidence: 99%

“…It is not clear, which mechanisms produce the Pc5 wave power in the auroral zone. However, based on studies on some features of storm-time substorms (Pilipenko et al, 2001;Kozyreva et al, 2016), Pc5 wave power variations in that region are connected to the auroral electrojet and fieldaligned currents in a way that is not presently understood. Higher than magn.…”

Section: Discussionmentioning

confidence: 99%

See 1 more Smart Citation

Solar cycle evolution of ULF wave power in solar wind and on ground

Hynönen

Tanskanen

Francia

2020

J. Space Weather Space Clim.

View full text Add to dashboard Cite

The solar cycle evolution of the ultra-low frequency (ULF) power was studied in solar wind and on ground. We aim finding out how the ULF power in interplanetary and on ground magnetic field evolves over the solar cycle 23 (SC23) and how well do they follow each other in monthly time scales. The hourly power of the ULF waves was computed in the Pc5 frequency range 2–7 mHz for years 1998–2008. The highest wave power in SC23 is found to occur in late 2003 and the lowest at the solar minimum. Ground ULF power follows the IMF power and solar wind speed, particularly well during declining phase. The ULF power in winter exceeds the ULF power in other seasons during the declining phase of SC23, while equinoxes dominate in the ascending phase and the solar maximum. The ground ULF power was found to rise with magnetic latitude from 54° to 73°, after which Pc5 power decreases towards the polar cap. The Pc5 power in the auroral zone is larger in the nightside than the dayside due to substorm activity implying that magnetotail processes are an important contributor to the nightside ULF power.

show abstract

Section: Discussionmentioning

confidence: 99%

Section: Discussionmentioning

confidence: 99%

Solar cycle evolution of ULF wave power in solar wind and on ground

Hynönen

Tanskanen

Francia

2020

J. Space Weather Space Clim.

View full text Add to dashboard Cite

show abstract

“…Even when one auroral station is in darkness while the other is in sunlight, rather than differing by an order of magnitude, Σ (N) and Σ (S) are usually much closer to a factor of 2. It is important for the considered problem, because the "epicenters" of the Pc5 power (Kozyreva et al, 2016) and TCV amplitude (Sibeck et al, 1996) are typically located near the equatorward auroral oval boundary.…”

Section: Additional Factors Influencing Ground Magnetometer Observationsmentioning

confidence: 99%

Electromagnetic Fields of Magnetospheric ULF Disturbances in the Ionosphere: Current/Voltage Dichotomy

et al. 2019

View full text Add to dashboard Cite

A circuit analogy for magnetosphere‐ionosphere current systems has two extremes for drivers of ionospheric currents: the “voltage generator” (ionospheric electric fields/voltages are constant, while current varies) and the “current generator” (current is constant, while the electric field varies). Here we indicate another aspect of the magnetosphere‐ionosphere interaction, which should be taken into account when considering the current/voltage dichotomy. We show that nonsteady field‐aligned currents interact with the ionosphere in a different way depending on a forced driving or resonant excitation. A quasi‐DC driving of field‐aligned current corresponds to a voltage generator, when the ground magnetic response is proportional to the ionospheric Hall conductance. The excitation of resonant field line oscillations corresponds to the current generator, when the ground magnetic response only weakly depends on the ionospheric conductance. According to the suggested conception, quasi‐DC nonresonant disturbances correspond to a voltage generator. Such ultralow frequency (ULF) phenomena as traveling convection vortices and Pc5 waves should be considered as the resonant response of magnetospheric field lines, and they correspond to a current generator. However, there are quite a few factors that may obscure the determination of the current/voltage dichotomy.

show abstract

“…For example, in Kozyreva et al. (2016) and Martines‐Bedenko et al. (2018) it was found that a latitudinal maximum of Pc5 pulsations is localized around the equatorward auroral boundary.…”

Section: Discussionmentioning

confidence: 99%

“…This may be important for ULF waves. For example, in Kozyreva et al (2016) and Martines-Bedenko et al (2018) it was found that a latitudinal maximum of Pc5 pulsations is localized around the equatorward auroral boundary. The way to estimate contribution of auroral precipitation into the ionospheric conductance is to combine the IRI model and the OVATION-prime model, which gives information on the location of the auroral oval (Pilipenko et al, 2021).…”

Section: Discussionmentioning

confidence: 99%

Diagnostics of the Ionospheric Conductivity Based on Spacecraft Observations of the Magnetospheric ULF Waves

2023

View full text Add to dashboard Cite

In 27 October 2012 an Alfvén wave of the Pc4 range was observed with Van Allen Probe A. The parallel Poynting flux of the wave was directed toward the Northern ionosphere. Assuming that this may be caused by the asymmetry of the ionospheric conductivity between the Northern and Southern hemispheres, its effect on the standing structure of the Alfvén wave was investigated. For this purpose, the analytical model with straight magnetic field lines was used. As a result, the method for estimation of the Northern and Southern ionospheric conductivity was developed. It allows to reconstruct the parallel structure of Alfvén waves under various conditions of the ionospheric conductivity. With the method developed, the ionospheric conductivity for the 27 October 2012 event was evaluated and compared with ionosphere model IRI‐2016 results.

show abstract

Correspondence between the ULF wave power spatial distribution and auroral oval boundaries

Abstract: waves, but it could be significant for the development of more adequate models.

Cited by 6 publications

References 31 publications

Solar cycle evolution of ULF wave power in solar wind and on ground

Solar cycle evolution of ULF wave power in solar wind and on ground

Electromagnetic Fields of Magnetospheric ULF Disturbances in the Ionosphere: Current/Voltage Dichotomy

Diagnostics of the Ionospheric Conductivity Based on Spacecraft Observations of the Magnetospheric ULF Waves

Contact Info

Product

Resources

About