Ionospheric irregularities and their coupling with the magnetosphere and radio wave propagation in and emissions from the ionosphere

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This research is to advance understanding of the interaction of the 'atmosphere' of the Sun with the upper atmosphere (above 100 km) of the Earth. Specifically my research interest involves explaining the natural phenomena occurring in the ionosphere portion of the terrestrial upper atmosphere. The composition and dynamics of this ionized medium is dominated by electric and magnetic fields and therefore exhibits significantly different behaviour than the neutral atmosphere we are familiar with on the Earth's surface. Beginning at 100 km altitude, only rockets or satellites can directly observe the ionosphere; however, one method to remotely probe this region is by using radio and radar techniques. As experimentalists, my students and I use these radio techniques and instruments, both ground and satellite based, to measure the composition and dynamics of the ionosphere. We have just developed and deployed a new extremely highly advanced completely digital ground based very high frequency (VHF) radar, known as ICEBEAR, for studying the lower portion, or E-region, of the ionosphere. We also work with an international team of radar physicists who study the upper portion of the ionosphere, the F-region, with a network of high frequency (HF) radars known as SuperDARN. These radars give details about motions and flows in the ionosphere, and the new ICEBEAR radar uses advanced radar techniques to do a much better job of this than in the past. We also use a Canadian space science satellite (ePOP/RRI) to study how radio waves propagate through the ionosphere, giving new insight about its structure. Recently, we started using RRI to observe the naturally occurring radio emissions, such as whistler waves, generated in the near-Earth space environment. Working closely with my students, who will develop advanced data analysis skills and independent research abilities, we will exploit the abilities of these radio instruments to foster a clearer understanding of the dynamics and structure in the ionosphere. Research using the ICEBEAR radar will give new insight and understanding of the coupling between closure currents in the E-region ionosphere, which are sourced from the magnetosphere above, and about the scattering physics itself. Knowing the electron density in the ionosphere is critical for understanding the physics there, but rarely are measurements available. We will refine a technique we have developed which uses SuperDARN observations to calculate electron density measurements over the very large SuperDARN field of view. Thus, giving a new and much needed source of this highly desirable parameter. With similar objectives, the polarisation abilities of the RRI instrument will be used to generate electron density profiles and characterise structures in the ionosphere. The direct outcome of all this research will be student theses and journal papers, and well trained physicists and engineers to work in academia or the Canadian space industry.