Study of the Earth's ionosphere with ground-based radars and Swarm satellites

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The Earth's ionosphere is a conductive layer in the upper atmosphere. It is controlled by internal processes such as neutral winds, as well as the interaction between the Earth's magnetic field and the solar wind which carries the embedded interplanetary magnetic field (IMF). The global-scale electric field established in the ionosphere is a critical element in these interactions at the magnetospheric level. In the ionosphere, the electric field in combination with the geomagnetic field redistributes plasma at F region heights (~300 km) and drives strong electric currents at E region heights (~100 km). The proposed research seeks to improve our understanding of the distribution and circulation of ionospheric plasma as a function of solar wind conditions. The focus is on the identification of how ionospheric plasma motions lead to the formation of plasma structures of various scales. This will be achieved through synchronized measurements with several instruments properly positioned on the ground and in space. The research can be categorized into four themes. (1)  Study of meso-scale ionospheric plasma circulation patterns as a function of external drivers with a focus on IMF Bz>0 condition by observing simultaneous data from multiple SuperDARN radars near the North and South Poles. SuperDARN data will be supplemented by electric field measurements from the Swarm satellites and the incoherent scatter radars (ISR) at Resolute Bay. Observations will be tested against theoretical models of magnetospheric plasma flow.   (2) Examination of long-term trends and inter-hemispheric differences in electron density distribution and how this affects the occurrence of SuperDARN echoes. Additional focus will be on the topside ionosphere where a combination of ISR and Swarm measurements would provide new information on the poorly investigated High Arctic ionosphere. (3) Identifying the sources of mesoscale ionospheric structures with enhanced electron density persistent at middle latitudes. These are related to neutral winds and waves resulting from either intense particle precipitation events at high latitudes or atmospheric processes at the edges of the polar vortex. (4) Mechanisms of small-scale (decameter-meter) wave-like electron density irregularity formation at E region heights in the presence of strong electric currents. Joint HF and VHF observations will be tested against recent non-linear theories. The planned research will contribute to the Canadian efforts in forecasting harmful "space weather" events affecting pipelines through excessive corrosion and predictions of HF communication systems' operability at high latitudes critical for the airline operators and air-defense monitoring with over-the-horizon radars. The research program focuses on training undergraduate and graduate students for work in the Canadian satellite, aerospace, and related industries, as well as for agencies performing atmospheric environment monitoring.