Abstract
The solar wind carries plasma and magnetic fields from the Sun. Being a gas of electrically charged particles, it will interact strongly with the magnetic field of the Earth. The main consequence of the interaction is that most of the solar wind is deflected around the Earth, but a detailed look reveals an abundance of complex processes which may, in extreme cases, affect our infrastructure by interfering with or destroying satellites and power grids. Fortunately, a more commonly observed effect is the generation of light in the upper parts of the atmosphere, known as Aurora. This thesis aims to increase our knowledge of the processes occurring in the boundary layers that connect the solar wind to the near-Earth environment. Of the three papers in this thesis, the first examines the consequences of a seemingly small change in the interplanetary magnetic field, which triggers a cascade of events that seriously disturb the magnetospheric boundary layers. This in turn leads to local disturbances of the magnetic field at the ground level. A large part of the field of space physics is the study of Magnetosphere–Ionosphere coupling (M-I coupling). Through waves, precipitating plasma and electrical currents, the forces applied to the magnetosphere by its interaction with the solar wind are transmitted down to the ionosphere. The second and third papers investigate interactions between the electric field, plasma and currents in the cusp, a region where solar wind plasma precipitates into the upper atmosphere.
List of papers
Paper 1: THEMIS observations of extreme magnetopause motion caused by a hot flow anomaly. K. S. Jacobsen, T. D. Phan, J. P. Eastwood, D. G. Sibeck, J. I. Moen, V. Angelopoulos, J. P. McFadden, M. J. Engebretson, G. Provan, D. Larson, and K.-H. Fornacon JOURNAL OF GEOPHYSICAL RESEARCH, VOL. 114, A08210, 2009 https://doi.org/10.1029/2008JA013873 |
Paper 2: On the correlation between Broad-Band ELF wave power and ion fluxes in the cusp. Manuscript prepared for Ann. Geophys. The paper is not available in DUO. |
Paper 3: Quasistatic electric field structures and field-aligned currents in the polar cusp region. JOURNAL OF GEOPHYSICAL RESEARCH The paper is not available in DUO. |