Space physics and policy for contemporary society

Cassak, P. A.; Emslie, A. G.; Halford, A. J.; Baker, D. N.; Avery, S. K.; Fisk, L. A.

doi:10.1002/2017ja024219

Cited by 17 publications

(14 citation statements)

References 29 publications

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“…Given the importance of the potential serious and widespread problems associated with disruptions to power systems, GICs have been characterized as one of the top space weather hazards by the scientific community and policy makers. This constant and imminent threat has led to regulatory actions not only in the United States but also at an international level (see, e.g., Cassak et al, 2017;Jonas & McCarron, 2015;Knipp, 2015;Pulkkinen et al, 2017). GICs are also a very common subject for modeling studies whose goal corresponds to the improvement of GIC forecasting (Barbosa et al, 2015(Barbosa et al, , 2017Blake et al, 2016;Ngwira et al, 2009;Pulkkinen, 2015;Torta et al, 2017;Zhang et al, 2015Zhang et al, , 2016.…”

Section: Introductionmentioning

confidence: 99%

Geomagnetically Induced Currents Caused by Interplanetary Shocks With Different Impact Angles and Speeds

et al. 2018

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The occurrence of geomagnetically induced currents (GICs) poses serious threats to modern technological infrastructure. Large GICs result from sharp variations of the geomagnetic field (dB/dt) caused by changes of large‐scale magnetospheric and ionospheric currents. Intense dB/dt perturbations are known to occur often in high‐latitude regions as a result of storm time substorms. Magnetospheric compressions usually caused by interplanetary shocks increase the magnetopause current leading to dB/dt perturbations more evident in midlatitude to low‐latitude regions, while they increase the equatorial electrojet current leading to dB/dt perturbations in dayside equatorial regions. We investigate the effects of shock impact angles and speeds on the subsequent dB/dt perturbations with a database of 547 shocks observed at the L1 point. By adopting the threshold of dB/dt = 100 nT/min, identified as a risk factor to power systems, we find that dB/dt generally surpasses this threshold when following impacts of high‐speed and nearly frontal shocks in dayside high‐latitude locations. The same trend occurs at lower latitudes and for all nightside events but with fewer high‐risk events. Particularly, we found nine events in equatorial locations with dB/dt > 100 nT/min. All events were caused by high‐speed and nearly frontal shock impacts and were observed by stations located around noon local time. These high‐risk perturbations were caused by sudden strong and symmetric magnetospheric compressions, more effectively intensifying the equatorial electrojet current, leading to sharp dB/dt perturbations. We suggest that these results may provide insights for GIC forecasting aiming at preventing degradation of power systems due to GICs.

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Section: Introductionmentioning

confidence: 99%

Geomagnetically Induced Currents Caused by Interplanetary Shocks With Different Impact Angles and Speeds

et al. 2018

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“…The primary reason is because of space weather implications (Cassak, ); a number of physical phenomena causing space hazards to our technological infrastructure are discussed in the boxed text. Space weather impacts a staggering array of aspects of public life and public policy (e.g., Cassak, Emslie, et al, ). The potential damage to satellites impacts commerce (space communication), transportation (airlines losing communication during polar routes), the military and homeland security (communication), agriculture (communication), the environment/public works and infrastructure (the power grid), energy (pipeline erosion), and manned space travel (radiation danger for missions to the Moon and/or Mars).…”

Section: Magnetic Reconnection and Its Impactsmentioning

confidence: 99%

Magnetic Reconnection in the Space Sciences: Past, Present, and Future

2020

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Magnetic reconnection converts, often explosively, stored magnetic energy to particle energy in space and in the laboratory. Through processes operating on length scales that are tiny, it facilitates energy conversion over dimensions of, in some cases, hundreds of Earth radii. In addition, it is the mechanism behind large current disruptions in fusion machines, and it can explain eruptive behavior in astrophysics. We have known about the importance of magnetic reconnection for quite some time based on space observations. Theory and modeling employed magnetized fluids, a very simplistic description. While successful at modeling the large‐scale consequences of reconnection, it is ill suited to describe the engine itself. This is because, at its heart, magnetic reconnection in space is kinetic, that is, governed by the intricate interaction of charged particles with the electromagnetic fields they create. This complex interaction occurs in very localized regions and involves very short temporal variations. Researching reconnection requires the ability to measure these processes as well as to express them in models vastly more complex than fluid approaches. Until very recently, neither of these capabilities existed. With the advent of NASA's Magnetospheric Multiscale mission and modern modeling advances, this has now changed, and we have now determined its small‐scale structure in exquisite detail. In this paper, we review recent research results to predict what will be achieved in the future. We discuss how reconnection contributes to the evolution of larger‐scale systems, and its societal impacts in the context of threatening space hazards, customarily referred to as “space weather.”

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“…The magnetic reconnection is driven during the geomagnetic storms that cause heating of the background plasma. The aurora lights at the Earth's poles that result when the accelerated particles penetrate down to Earth's atmosphere could produce also large magnetic disturbances [7]. (ii) the occurrence of magnetic reconnection near the sunspots is the mechanism behind the propagation of billions joules of energy that called solar flares.…”

Section: Introductionmentioning

confidence: 99%

The mechanism that drives electrostatic solitary waves to propagate in the Earth's magnetosphere and solar wind

Afify¹,

Tolba²,

Moslem³

2022

Preprint

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The origin of the solitary waves in the Earth's magnetosphere and the solar wind, particularly close to the magnetic reconnection regions, is still an open question. For that purpose, we used the fluid model to obtain the mechanism behind the formation of solitary waves in space plasmas with a variety of components. Our findings reveal that at the separatrix of the magnetic reconnection in the Earth's magnetotail, the counter-ejected electron beam leads to a broadening of the pulse amplitude. While increasing the electron beam positive velocity causes a bit increase in the soliton amplitude. Moreover, we observed that the soliton profile is very sensitive to the plasma parameters like density and temperature. The calculated electric field using the current model and the measured electric field in the Earth's magnetosphere and solar wind is highlighted.

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Space physics and policy for contemporary society

Cited by 17 publications

References 29 publications

Geomagnetically Induced Currents Caused by Interplanetary Shocks With Different Impact Angles and Speeds

Geomagnetically Induced Currents Caused by Interplanetary Shocks With Different Impact Angles and Speeds

Magnetic Reconnection in the Space Sciences: Past, Present, and Future

The mechanism that drives electrostatic solitary waves to propagate in the Earth's magnetosphere and solar wind

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