Solar Wind and Interplanetary Magnetic Field Influences on the Earth's Space Environment: Solar Wind-Magnetosphere-Ionosphere Coupling

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The majority of the energy budget of the Earth's space environment is controlled by the energy transfer between the solar wind and the magnetosphere. The degree to which the highly variable solar wind couples to the magnetosphere controls the access of solar wind particles precipitating along the Earth's magnetic field lines to the upper atmosphere. Since all points in the magnetosphere are linked to the ionosphere by the geomagnetic field lines, the ionosphere acts as a large screen onto which magnetosphere dynamics are projected, allowing the ground-based instruments to remotely sense nearly the entirety of geospace. I will investigate modes of convection in the magnetosphere, which are important to understanding the response of the system to external forcing by the solar wind and interplanetary magnetic field. The magnetosphere can experience three phenomena that have, until now, been classified as physically distinct phenomena: steady magnetospheric convection, substorms, and sawtooth events. Recent work suggests that these response modes may lie more along a continuum of response. The global-scale maps of ionospheric convection that the international array of radars called SuperDARN obtains every minute are ideally suited for this work. I will also investigate the relationship between space weather and climate in the key coupling region between the two-the Earth's ionosphere. In the study of global climate, solar variability has been identified as a possible source of climate change on Earth. The mechanism remains to be identified, and next to nothing is known about how the two regions may be connected. Intriguing studies in the past have shown a correlation between the intensity of weather systems and the orientation of the interplanetary magnetic field. The ionosphere-mesosphere- thermosphere layer that lies between the electrified space environment and the neutral atmosphere holds the key to understanding how solar-terrestrial coupling may affect climate. Initial work suggests that the polar caps, where the solar wind and IMF are directly connected to the geomagnetic field, play an important role.