Dynamics of Magnetosphere-Ionosphere Coupling
Processes, Rates, Impacts
Sun-Earth Connection Theory
Group
Principal Investigator: William
Lotko
Co-Investigators: Richard Denton,
Mary Hudson, John Lyon,
David Murr, Barrett Rogers, Anatoly Streltsov
Collaborators (NCAR): Alan Burns, Wenbin Wang, Michael
Wiltberger
Project
Summary
A synergistic research effort will explore and advance theoretical understanding of the causal agents, regional couplings, scale-interactions, and particle kinetics of magnetospheric and ionospheric variability in the ultra-low-frequency regime (time scales from 1 sec to 30 min). The impacts of magnetotail transients and pulsations (periods of 10-30 min), magnetospheric boundary and dayside merging dynamics (1-10 min), and geomagnetic cavity and fieldline oscillations (0.5-10 min) on low-altitude energy deposition will be investigated via
• global MHD simulation of the solar wind-magnetosphere-ionosphere interaction,
• regional reduced-MHD simulation of auroral and polar-cusp flux tubes, and
• gyrokinetic simulation of collisionless dissipation in thin
Alfvén wave structures and current layers.
The impacts on the magnetosphere of collisionless absorption of energy at low altitude – leading to the production of plasma beams and heat, massive episodic outflows of ionospheric ions, and scale-interactive intensification of auroral resonator oscillations (1-30 sec) – will be investigated by linking the above simulations with models for
• electrodynamic feedback from the ionosphere,
• low-altitude, field-aligned plasma dynamics including transport, and
• large-scale particle kinetics.
A legacy of the project will be a causal, predictive model for time-variable exchange of mass flux, electron energy flux and Poynting flux between the two regions.
The research will address complex, large-scale problems of the magnetosphere-ionosphere interaction such as: the genesis, evolution and fate of polar ionospheric patches and their effects on magnetospheric structure and dynamics; the relationship between substorm-enhanced O+ outflows, plasmasheet reformation and ring current development; and the regulation of interhemispherical asymmetries in auroral precipitation, auroral plasma cavities, and ion outflow.
Relevance
Predictive results derived from this research will be validated using satellite and ground-based data. In areas where existing data analysis techniques are inadequate for validating model results, novel diagnostic techniques will be developed and demonstrated using simulation. The research will significantly advance the theoretical framework for interpreting multi-point, multi-instrument measurements made on high-altitude, magnetospheric, low-altitude, polar-orbiting, and ground-based observational platforms. Synoptic data analysis performed in conjunction with the theory, models and analysis tools to be developed here will provide new capabilities for assessing the energy flow from global-scale ULF dynamics and boundary oscillations to internal magnetospheric and ionospheric processes involving MHD resonance layers, resonant particle energization, auroral activation, and ionospheric dissipation and outflow.
Publications
(2001 – 2004)
Elkington, S.R., M.K. Hudson, M.J. Wiltberger, and
J.G. Lyon, MHD/Particle simulations of radiation belt dynamics, J. Atoms. Solar Terr. Phys. 64, 607-615 doi:10.1016/S1364-6826(02)00018-4, 2003.
Elkington, S.R., M.K. Hudson, A.A. Chan, Resonant
acceleration and
diffusion of outer zone electrons in an asymmetric geomagnetic
field, J. Geophys. Res. 108,1029, 2003.
Hudson, M.K., R.E. Denton, M.R. Lessard, E.G. Miftakhova
and R.R. Anderson, A study of Pc-5 ULF oscillations, Ann. Geophysicae 22, 289-302, 2004..
Hudson, M.K., B.T. Kress, J.E. Mazur, K.L. Perry, and
P.L. Slocum, 3D Modeling of Shock-Induced Trapping of Solar Energetic Particles
in the Earth's Magnetosphere, J. Atmos.
Sol. Terr. Phys., submitted, 2004.
Lessard,
M.R., W. Lotko, W. Peria, and C. Carlson, Characteristics of growth-phase
auroral arcs, J. Geophys. Res., in
preparation, 2003.
Lotko, W.
(contributing author), Auroral Plasma Physics, ed. by Paschmann, G., S.
Haaland and R. Treumann, Kluwer Academic Publishers, Boston/Dordrecht/London,
2003.
Lotko, W., M. Lessard, C.W. Carlson, F.R. Fenrich, W.
Peria and R.C. Elphic, Collisionless dissipation in a field line resonance, J.
Geophys. Res., submitted,
2004.
Lotko, W., Inductive magnetosphere-ionosphere
coupling, J. Atmos. Sol. Terr. Phys.,
accepted, 2004.
Lotko, W., Two-fluid shear Alfvén-slow mode coupling,
to be submitted, 2004.
Pokhotelov, D., Effect of the active auroral
ionosphere on magnetosphere-ionosphere coupling, Ph.D. dissertation, Thayer School
of Engineering, Dartmouth College, Hanover, NH, 2002.
Pokhotelov, D., W. Lotko and A.V.
Streltsov, Diurnal and seasonal control of auroral precipitation, Geophys. Res. Lett. 29(10),
1437, doi:10.1029/2001GL014010, 2002.
Pokhotelov, D.,
Pokhotelov, D., W. Lotko and A.V. Streltsov,
Simulations of resonant Alfvén waves generated by artificial HF heating of the
auroral ionosphere, Annales Geophysicae, submitted, 2003.
Proehl, J., W. Lotko, I. Kouznetsov and
Shepherd, S.G. and F.
Shubitidze, Method of auxiliary sources for calculating the magnetic and
electric fields induced in a layered Earth, J. Atmos. Solar-Terr. Phys. 65(10), 1151-1160,
10.1016/S1364-6826(03)00159-7, 2003.
Streltsov, A.V., W. Lotko, A. Keiling and J.R.
Wygant, Numerical modeling of Alfvén waves observed by POLAR in the plasma
sheet boundary layer, J. Geophys. Res. 107(A8), 1173, doi:10.1029/2001JA000233, 2002.
Streltsov, A.V. and
Streltsov, A.V. and W. Lotko, Small-scale electric
fields in downward auroral current channels, J. Geophys. Res. 108(A7), 1289, doi:10.1029/2002JA009806,
2003.
Streltsov, A.V. and E. V. Mishin, Numerical modeling
of localized electromagnetic waves in the nightside subauroral zone, J. Geophys. Res., 108(A8), 1332, doi:10.1029/2003JA009858, 2003.
Streltsov, A.V. and J.
C. Foster, Field line resonances in the nightside sub-auroral zone, Phys. Plasmas, in press, 2004.
Streltsov, A.V. and W. Lotko,
Multi-scale electrodynamics of the ionosphere-magnetosphere system, J. Geophys. Res., submitted, 2004.
Takahashi, K., R.E. Denton, and D.L. Gallagher,
Toroidal wave frequency at L = 6-10: AMPTE/CCE observation and comparison with
theoretical model, J. Geophys. Res. 107(A2), 1020, doi:10.1029/2001JA000197, 2002.
Takahashi, K., R.E. Denton, R.R. Anderson, and W.J.
Hughes, The frequencies of the harmonics of standing Alfvén waves and their
implication to plasma mass distribution along geomagnetic field lines:
Statistical analysis of CRRES data, J.
Geophys. Res., submitted,
2004.
Wiltberger, M., R. E. Lopez, and J. G. Lyon,
Magnetopause erosion: A global view from MHD simulation, J. Geophys. Res. 108, doi:10.1029/2002JA009564,
2003.
Wiltberger, M., J. G. Lyon, and C. C. Goodrich,
"Results from the Lyon-Fedder-Mobarry global magnetospheric model for the
electrojet challenge, J. Atmos. Solar Terr. Phys., 65, 1213-1222, 2003.
Wiltberger, M., R. E. Lopez, and J. G. Lyon, Results
from magnetospheric Gadanken experiments using the LFM, Adv. Sp. Res.,
submitted, 2002.
Wygant, J.R., A. Keiling, C.A. Cattell, R.L. Lysak,
M. Temerin, F.S. Mozer, C.A. Kletzing, J.D. Scudder, A.V. Streltsov, W. Lotko,
and C.T. Russell, Evidence for kinetic Alfvén waves and parallel electron
energization at the high-latitude plasma sheet, J. Geophys. Res. 107(A8),
doi:10.1029/2001JA900113, 2002.
Project
Descriptions
pdf: 2004
(6.7MB) 2001 (423 kB) 1998 (178 KB)