Project Summary


Project Description



School of




& Astronomy





Dynamics of Magnetosphere-Ionosphere Coupling

Heliophysics Theory Project

Dartmouth College

Sponsored by NASA Heliophysics Science Division


Principal Investigator: William Lotko

Co-Investigators: Richard Denton, John Lyon, Barrett Rogers (all at Dartmouth), Mike Wiltberger (NCAR/HAO)

Collaborators: Allan Burns, Wenbin Wang (both at NCAR/HAO)


Research Highlights


Project Summary


Objectives and Methodology:

This project addresses the challenge to explain, model and predict “how mass and energy flows in the magnetosphere-ionosphere system determine and control their coupled behavior.” It takes a critical step in integrating theoretical and empirical knowledge of the three key agents of dynamic MI coupling – energy deposition, electron precipitation and ion outflows – to improve our ability to predict regional and global dynamics. Our primary research objectives are to determine: 1) how these individual elements interact to regulate their collective behavior; 2) how they determine and control the MI interaction; and 3) how they impact the greater solar wind – magnetosphere - ionosphere interaction over the spectrum of interplanetary driving conditions.

The simulation models and theory to be developed by the project will enable exploration and discovery of integrated system behavior in geospace. Specifically, the effects of solar wind-magnetospheric dynamics on low-altitude energy deposition, and the effects of ionospheric activity on the magnetosphere including scale-interactive transport of magnetic flux, mass and en­ergy, will be investigated via simulation of the 1) global multifluid-magnetohydrody­namics of the solar wind-magnetosphere-ionosphere interaction; 2) global thermosphere-iono­sphere electrodynamics and circulation; and 3) electrodynamic and kinetic linkages involving quasistatic and Alfvén wave dynamics, ionospheric outflows, and electron precipitation in the collisionless “gap region.” The coupled global models will be used to investigate system behavior via controlled numerical experiments, e.g., we have discovered in past experiments, with and without ionospheric outflows, that superfluent outflows have the capacity to modify the solar wind – magnetosphere interaction and the dayside-nightside balance of reconnection. A legacy of the project will be a causal, predictive model for time-variable exchange of mass, electrons and electromagnetic energy fluxes between the magnetosphere and ionosphere.

Roadmap for Heliophysics Science and Technology 2009-2030

Relevance to NASA Strategic Objectives:

By advancing the state-of-the-art in treating the magnetosphere-ionosphere as a single integrated system, this project directly supports NASA Heliophysics Science Plan 2007-2016 to answer the question of how the geospace system responds to solar variability, to understand the fundamental physical processes of the space environment from the Sun to Earth, and to develop the capability to predict extreme and dynamic conditions in space. In providing a global systems perspective on the origins of near earth plasma and dynamic geospace coupling, it is also directly aligned with science targets and future mission planning of the Roadmap for Heliophysics Science and Technology 2009–2030.

Project-Related Publications and Reports (since 2007)

Brambles, O.J., W. Lotko, P.A. Damiano, B. Zhang, M. Wiltberger, J. Lyon (2010), Effects of causally driven cusp O+ outflow on the stormtime M-I system using a multifluid global simulation, J. Geophys. Res. 115, A00J04, doi:10.1029/2010JA015469.

Brambles, O.J., W. Lotko, B. Zhang, M. Wiltberger, J. Lyon, R.J. Strangeway (2011), Magnetosphere sawtooth oscillations induced by ionospheric outflow, Science 332, 1183, doi:10.1126/science.1202869

Brizard, A.J., R.E. Denton, B. Rogers, W. Lotko (2008). Nonlinear finite-Larmor-radius effects in reduced fluid models, Phys. Plasmas 15, 082302, doi:10.1063/1.2965827.

Claudepierre, S.G., M.K. Hudson, W. Lotko, J.G. Lyon, R.E. Denton  (2010), Solar wind driving of magnetospheric ULF waves: Field line resonances driven by dynamic pressure fluctuations, J. Geophys. Res. 115, A11202, doi:10.1029/2010JA015399.

Damiano, P.A., O.J. Brambles, W. Lotko, B. Zhang, M. Wiltberger, J. Lyon (2010), Effects of solar wind dynamic pressure on the ionospheric O+ fluence during the 31 August 2005 storm, J. Geophys. Res. 115, A00J07, doi:10.1029/2010JA015583.

Denton, R.E., B. Rogers, W. Lotko (2007). Reduced MHD equations with coupled Alfvén and sound wave dynamics, Phys. Plasmas 14, 102906, doi:10.1063/1.2786060.

Denton, R.E., B. Rogers, W. Lotko, A.V. Streltsov (2008). Effect of the radial boundary condition on Alfvén wave dynamics in reduced magnetohydrodynamics, Phys. Plasmas 15, 032106, doi:10.1063/1.2898409.

Denton, R.E., Y. Hu (2009), Symmetry boundary conditions, J. Computational Phys. 228(13), 4823–4835, doi:10.1016/

Denton, R.E., M.F. Thomsen, K. Takahashi, R.R. Anderson, H.J. Singer (2011), Solar cycle dependence of bulk ion composition at geosynchronous orbit, J. Geophys. Res. 116, A03212, doi:10.1029/2010JA016027.

Hu, Y., R.E. Denton (2009), Two-dimensional hybrid code simulation of electromagnetic ion cyclotron waves in a dipole magnetic field, J. Geophys. Res. 114, A12217, doi:10.1029/2009JA014570.

Hu, Y., R.E. Denton, J.R. Johnson (2010), Two‐dimensional hybrid code simulation of electromagnetic ion cyclotron waves of multi-ion plasmas in a dipole magnetic field, J. Geophys. Res., 115, A09218, doi:10.1029/2009JA015158.

Hu Y., R.E. Denton, Y. Lin (2010), The effect of heat flux on pressure evolution in the magnetosheath, J. Atmos. Solar Terr. Phys. 72(16), 1155-1162, doi:10.1016/j.jastp.2010.07.007.

Lessard, M.R., W. Lotko, J. LaBelle, W. Peria, C.W. Carlson, F. Creutzberg, D.D. Wallis (2007). Ground and satellite observations of the evolution of growth–phase auroral arcs,J. Geophys. Res. 112, A09304, doi:10.1029/2006JA011794.

Lotko, W. (2007). The magnetosphere–ionosphere system from the perspective of plasma circulation: A tutorial,  J. Atmos. Sol.-Terr. Phys. 69, 191-211, doi:10.1016/j.jastp.2006.08.011.

Lotko, W., M. Lessard, C.W. Carlson, F.R. Fenrich, W. Peria, R.C. Elphic (2011). Collisionless dissipation in a field line resonance, J. Geophys. Res.

Lyon, J. G., V. Merkin (2010). Multifluid equations for magnetohydrodynamics, J. Geophys. Res.

Melanson, P.D., W. Lotko, D.L. Murr, M. Wiltberger, J. G. Lyon (2011). Polar-region distributions of Poynting flux: Global models compared with observations, J. Atmos. Solar-Terr. Phys..

Melanson, P.D. (2007). Magnetosphere-Ionosphere Coupling: Understanding the Consequences of Energy and Mass Transport in the LFM Global MHD Simulation, M.S. Thesis, Dartmouth College.

Murr, D.L., W.J. Hughes (2007). The coherence between the IMF and high-latitude ionospheric flows: The dayside magnetosphere–ionosphere low-pass filter, J. Atmos. Sol.-Terr. Phys. 69, 223-233, doi:10.1016/j.jastp.2006.07.019.

Ouellette, J. E., B. N. Rogers, M. Wiltberger, J. G. Lyon (2010). Magnetic reconnection at the dayside magnetopause in global LFM simulations, J. Geophys. Res., 115, A08222, doi:10.1029/2009JA014886.

Ouellette, J. E., B. N. Rogers, M. Wiltberger, J. G. Lyon (2010). The scaling of magnetic reconnection at the dayside magnetopause, J. Geophys. Res.

Streltsov, A.V. (2007). Narrowing of the discrete auroral arc by the ionosphere, J. Geophys. Res. 112(A10), A10218, doi:10.1029/2007JA012402.

Streltsov, A.V. (2008). Effects of ionospheric heating on feedback-unstable electromagnetic waves, J. Geophys. Res. 113(A9), A09211, doi:10.1029/2008JA013199.

Streltsov, A.V., W. Lotko (2007). Coupling between density structures, electromagnetic waves and ionospheric feedback in the auroral zone,  J. Geophys. Res. 113, A05212, doi:10.1029/2007JA012594.

Streltsov, A.V., T. Karlsson (2008), Small-scale, localized electromagnetic waves observed by Cluster-result of magnetosphere-ionosphere interactions, Geophys. Res. Lett., 35, L22107, doi:10.1029/2008GL035956.

Streltsov, A. V., T. R. Pedersen, E. V. Mishin, A. L. Snyder (2010), Ionospheric feedback instability and substorm development, J. Geophys. Res., 115, A07205, doi:10.1029/2009JA014961.

Takahashi, K., R.E. Denton, H.J. Singer (2010), Solar cycle variation of geosynchronous plasma mass density derived from the frequency of standing Alfvén waves, J. Geophys. Res. 115, A07207, doi:10.1029/2009JA015243.

Watts, J.C. (2009), Multiresonator Dynamics in Regions of Field-Aligned Current, M.S. Thesis, Trustees of Dartmouth College, Hanover, NH.

Watts, J., W. Lotko, A.V. Streltsov (2007). Magnetosphere-ionosphere Alfvén resonator, J. Atmos. Sol.-Terr. Phys.

Wiltberger, M.,  R.S. Weigel, W. Lotko, J.A. Fedder (2009). Modeling seasonal variations in auroral particle precipitation in a global scale magnetosphere - ionosphere model, J. Geophys. Res. 114, A01204, doi:10.1029/2008JA013108.

Wiltberger, M., W. Lotko,  J.G. Lyon, P. Damiano, V. Merkin (2010), Influence of cusp O+ outflow on magnetotail dynamics in a multifluid MHD model of the magnetosphere, J. Geophys. Res. 115, A00J05, doi:10.1029/2010JA015579.

 Zhang, B.,  W. Lotko, M.J. Wiltberger, O.J. Brambles, P.A. Damiano (2011), A statistical study of magnetosphere–ionosphere coupling in the LFM global MHD model, J. Atmos. Sol.-Terr. Phys. 73(5-6), 686-702, doi:10.1016/j.jastp.2010.09.027.