scholarly journals Chasing Down the Slow Solar Wind

Eos ◽  
2016 ◽  
Vol 97 ◽  
Author(s):  
Larry Kepko
Keyword(s):  
Solar Wind ◽  
Slow Solar Wind ◽  
Earth’S Magnetosphere ◽  
Earth's Magnetosphere

The Sun's plasma blasts Earth's magnetosphere at more than a million miles per hour. The fastest pours from holes in the corona, but until recently the source of the "slow" solar wind was a mystery.

scholarly journals Space Weather Forecasting: What We Know Now and What Are the Current and Future Challenges?

2019 ◽  
Author(s):  
Bruce T. Tsurutani ◽  
Gurbax S. Lakhina ◽  
Rajkumar Hajra
Keyword(s):  
Solar Wind ◽  
Space Weather ◽  
Energetic Particle ◽  
High Speed ◽  
Weather Forecasting ◽  
Geomagnetic Storms ◽  
Magnetic Clouds ◽  
Slow Solar Wind ◽  
Earth’S Magnetosphere ◽  
Earth's Magnetosphere

Abstract. Geomagnetic storms are caused by solar wind southward magnetic fields that impinge upon the Earth’s magnetosphere (Dungey, 1961). How can we forecast the occurrence of these interplanetary events? We view this as the most important challenge in Space Weather. We discuss the case for magnetic clouds (MCs), interplanetary sheaths upstream of ICMEs, corotating interaction regions (CIRs) and high speed streams (HSSs). The sheath- and CIR-related magnetic storms will be difficult to predict and will require better knowledge of the slow solar wind and modeling to solve. There are challenges for forecasting the fluences and spectra of solar energetic particles. This will require better knowledge of interplanetary shock properties from the Sun to 1 AU (and beyond), the upstream slow solar wind and energetic seed particles. Dayside aurora, triggering of nightside substorms, and formation of new radiation belts can all be caused by shock and interplanetary ram pressure impingements onto the Earth’s magnetosphere. The acceleration and loss of relativistic magnetospheric killer electrons and penetrating electric fields in terms of causing positive and negative ionospheric storms are currently reasonable well understood, but refinements can still be made. The forecasting of extreme events (extreme shocks, extreme solar energetic particle events, and extreme geomagnetic storms (Carrington events or greater)) are also discussed. Energetic particle precipitation and ozone destruction is briefly discussed. For many of the studies, the Parker Solar Probe, Solar Orbiter, Magnetospheric Multiscale Mission (MMS), Arase, and SWARM data will be useful.

scholarly journals The physics of space weather/solar-terrestrial physics (STP): what we know now and what the current and future challenges are

2020 ◽  
Vol 27 (1) ◽  
pp. 75-119 ◽  
Author(s):  
Bruce T. Tsurutani ◽  
Gurbax S. Lakhina ◽  
Rajkumar Hajra
Keyword(s):  
Solar Wind ◽  
Space Weather ◽  
Energetic Particle ◽  
High Speed ◽  
Geomagnetic Storms ◽  
Interplanetary Space ◽  
Magnetic Clouds ◽  
Slow Solar Wind ◽  
Earth’S Magnetosphere ◽  
Earth's Magnetosphere

Abstract. Major geomagnetic storms are caused by unusually intense solar wind southward magnetic fields that impinge upon the Earth's magnetosphere (Dungey, 1961). How can we predict the occurrence of future interplanetary events? Do we currently know enough of the underlying physics and do we have sufficient observations of solar wind phenomena that will impinge upon the Earth's magnetosphere? We view this as the most important challenge in space weather. We discuss the case for magnetic clouds (MCs), interplanetary sheaths upstream of interplanetary coronal mass ejections (ICMEs), corotating interaction regions (CIRs) and solar wind high-speed streams (HSSs). The sheath- and CIR-related magnetic storms will be difficult to predict and will require better knowledge of the slow solar wind and modeling to solve. For interplanetary space weather, there are challenges for understanding the fluences and spectra of solar energetic particles (SEPs). This will require better knowledge of interplanetary shock properties as they propagate and evolve going from the Sun to 1 AU (and beyond), the upstream slow solar wind and energetic “seed” particles. Dayside aurora, triggering of nightside substorms, and formation of new radiation belts can all be caused by shock and interplanetary ram pressure impingements onto the Earth's magnetosphere. The acceleration and loss of relativistic magnetospheric “killer” electrons and prompt penetrating electric fields in terms of causing positive and negative ionospheric storms are reasonably well understood, but refinements are still needed. The forecasting of extreme events (extreme shocks, extreme solar energetic particle events, and extreme geomagnetic storms (Carrington events or greater)) are also discussed. Energetic particle precipitation into the atmosphere and ozone destruction are briefly discussed. For many of the studies, the Parker Solar Probe, Solar Orbiter, Magnetospheric Multiscale Mission (MMS), Arase, and SWARM data will be useful.

scholarly journals DIAMAGNETIC PLASMOIDS AS PART OF DIAMAGNETIC STRUCTURES OF THE SLOW SOLAR WIND AND THEIR IMPACT ON EARTH’S MAGNETOSPHERE

2019 ◽  
Vol 5 (4) ◽  
pp. 42-54
Author(s):  
Vladimir Parhomov ◽  
Viktor Eselevich ◽  
Maxim Eselevich ◽  
Aleksey Dmitriev ◽  
Tatyana Vedernikova
Keyword(s):  
Magnetic Field ◽  
Solar Wind ◽  
Slow Solar Wind ◽  
Small Scale ◽  
Short Term ◽  
Earth’S Magnetosphere ◽  
Earth's Magnetosphere ◽  
The Impact ◽  
Magnetic Disturbances ◽  
Density Plasma

We have shown that diamagnetic structures (DSs), which form the basis of the slow quasi-stationary solar wind (SW), are observed in Earth’s orbit as a sequence of DSs of various scales. The analysis of this phenomenon indicates that diamagnetic plasmoids in SW, whose concept was introduced by Karlsson in 2015, are identical to small-scale DSs. We have found that the impact of a sequence of DSs in the slow SW on Earth’s magnetosphere causes an increase in geomagnetic activity. Isolated DSs generate short-term magnetic disturbances whose duration is approximately equal to the DS duration. Hence, a sequence of DSs can cause sawtooth substorms. We emphasize that the interaction of DS in the slow SW under northward interplanetary magnetic field can be associated with penetration of DS high-density plasma into the magnetosphere.

scholarly journals DIAMAGNETIC PLASMOIDS AS PART OF DIAMAGNETIC STRUCTURES OF THE SLOW SOLAR WIND AND THEIR IMPACT ON EARTH’S MAGNETOSPHERE

2019 ◽  
Vol 5 (4) ◽  
pp. 34-45 ◽  
Author(s):  
Vladimir Parhomov ◽  
Viktor Eselevich ◽  
Maxim Eselevich ◽  
Aleksey Dmitriev ◽  
Tatyana Vedernikova
Keyword(s):  
Magnetic Field ◽  
Solar Wind ◽  
Slow Solar Wind ◽  
Small Scale ◽  
Short Term ◽  
Earth’S Magnetosphere ◽  
Earth's Magnetosphere ◽  
The Impact ◽  
Magnetic Disturbances ◽  
Density Plasma

We have shown that diamagnetic structures (DSs), which form the basis of the slow quasi-stationary solar wind (SW), are observed in Earth’s orbit as a sequence of DSs of various scales. The analysis of this phenomenon indicates that diamagnetic plasmoids in SW, whose concept was introduced by Karlsson in 2015, are identical to small-scale DSs. We have found that the impact of a sequence of DSs in the slow SW on Earth’s magnetosphere causes an increase in geomagnetic activity. Isolated DSs generate short-term magnetic disturbances whose duration is approximately equal to the DS duration. Hence, a sequence of DSs can cause sawtooth substorms. We emphasize that the interaction of DS in the slow SW under northward interplanetary magnetic field can be associated with penetration of DS high-density plasma into the magnetosphere.

scholarly journals Space Weather, SuperDARN and the Tasmanian Tiger

1997 ◽  
Vol 50 (4) ◽  
pp. 773 ◽  
Author(s):  
Raymond A. Greenwald
Keyword(s):  
Solar Wind ◽  
Electric Fields ◽  
Space Weather ◽  
Interplanetary Space ◽  
Rapid Evolution ◽  
Upper Atmosphere ◽  
Global Network ◽  
Pressure Gradients ◽  
Earth’S Magnetosphere ◽  
Earth's Magnetosphere

The plasma environment extending from the solar surface through interplanetary space to the outermost reaches of the Earth’s atmosphere and magnetic field is dynamic, often disturbed, and capable of harming humans and damaging manmade systems. Disturbances in this environment have been identified as space weather disturbances. At the present time there is growing interest in monitoring and predicting space weather disturbances. In this paper we present some of the difficulties involved in achieving this goal by comparing the processes that drive tropospheric-weather systems with those that drive space-weather systems in the upper atmosphere and ionosphere. The former are driven by pressure gradients which result from processes that heat and cool the atmosphere. The latter are driven by electric fields that result from interactions between the streams of ionised gases emerging from the Sun (solar wind) and the Earth’s magnetosphere. Although the dimensions of the Earth’s magnetosphere are vastly greater than those of tropospheric weather systems, the global space-weather response to changes in the solar wind is much more rapid than the response of tropospheric-weather systems to changing conditions. We shall demonstrate the rapid evolution of space-weather systems in the upper atmosphere through measurements with a global network of radars known as SuperDARN. We shall also describe how the SuperDARN network is evolving, including a newly funded Australian component known as the Tasman International Geospace Environmental Radar (TIGER).

A UNIFYING THEORY OF HIGH-LATITUDE GEOPHYSICAL PHENOMENA AND GEOMAGNETIC STORMS

1961 ◽  
Vol 39 (10) ◽  
pp. 1433-1464 ◽  
Author(s):  
W. I. Axford ◽  
C. O. Hines
Keyword(s):  
Solar Wind ◽  
Steady State ◽  
High Latitude ◽  
Geomagnetic Storms ◽  
High Latitudes ◽  
Full Understanding ◽  
Earth’S Magnetosphere ◽  
Trapped Particles ◽  
Outer Portion ◽  
Earth's Magnetosphere

This paper is concerned with the occurrence at high latitudes of a large number of geophysical phenomena, including geomagnetic agitation and bay disturbances, aurorae, and various irregular distributions of ionospheric electrons. It shows that these may all be related in a simple way to a single causal agency, namely, a certain convection system in the outer portion of the earth's magnetosphere. The source of this convection is taken to be a viscous-like interaction between the magnetosphere and an assumed solar wind, though other sources of an equivalent nature may also be available. The model is capable of accounting for many aspects of the phenomena concerned, including the morphology of auroral forms and the occurrence of 'spiral' patterns in the loci of maximum intensities of several features. It also bears directly on the steady state of the magnetosphere, and in particular on the production of trapped particles in the outer Van Allen belt. In short, it provides a new basis on which a full understanding of these several phenomena may in time be built.

scholarly journals Solar wind interaction with the Earth's magnetosphere: the role of reconnection in the presence of a large scale sheared flow

2009 ◽  
Vol 16 (1) ◽  
pp. 1-10 ◽  
Author(s):  
F. Califano ◽  
M. Faganello ◽  
F. Pegoraro ◽  
F. Valentini
Keyword(s):  
Magnetic Field ◽  
Solar Wind ◽  
Magnetic Reconnection ◽  
Large Scale ◽  
Initial Conditions ◽  
Magnetic Layer ◽  
Magnetic Islands ◽  
Solar Wind Interaction ◽  
Earth’S Magnetosphere ◽  
Earth's Magnetosphere

Abstract. The Earth's magnetosphere and solar wind environment is a laboratory of excellence for the study of the physics of collisionless magnetic reconnection. At low latitude magnetopause, magnetic reconnection develops as a secondary instability due to the stretching of magnetic field lines advected by large scale Kelvin-Helmholtz vortices. In particular, reconnection takes place in the sheared magnetic layer that forms between adjacent vortices during vortex pairing. The process generates magnetic islands with typical size of the order of the ion inertial length, much smaller than the MHD scale of the vortices and much larger than the electron inertial length. The process of reconnection and island formation sets up spontaneously, without any need for special boundary conditions or initial conditions, and independently of the initial in-plane magnetic field topology, whether homogeneous or sheared.

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