Triggered Large-scale Auroral Disturbances and Poleward Boundary Intensifications (PBIs): Polar Lonospheric Convection Evolution and Structure

University Of California-Los Angeles, Los Angeles CA

Investigators

Abstract

In order to understand and predict geomagnetic disturbances, it is necessary to identify the different types of disturbances, how they relate to their ultimate energy source in the solar wind, and what the physical processes are that cause the different disturbance types. Different types of large-scale disturbances are related to different types of discontinuities of the solar wind plasma and interplanetary magnetic field (IMF), and to the resulting changes in plasma flows in the polar-cap ionosphere. This project will be directed toward firmly establishing the relationships between solar wind and IMF changes, the manifestation of these changes in reconnection related ionospheric flows on the dayside, and the resulting types of auroral-zone disturbances. We will also initiate a thorough study of how the solar wind and IMF changes and the auroral-zone disturbances are related to the formation and decay of the nightside Harang electric field reversal. It is particularly timely to now study the relationships between solar wind plasma and IMF changes, polar-cap and Harang region ionospheric flows, and the development of the different types of auroral disturbances because of recent instrument deployments, as well as the recent development and availability of improved techniques for mapping the measurements of the solar wind and IMF conditions made by spacecraft to the point where the interaction with the Earth's magnetosphere takes place. New SuperDARN radars have recently been installed that for the first time will allow good coverage of the Harang region and its evolution with respect to dayside convection, and all-sky imagers are being deployed throughout the Canadian Arctic that will give unprecedented ground coverage of the Canadian portion of the auroral oval. The goal of this research is to take advantage of this unprecedented opportunity to concretely determine the relations between the IMF and solar wind dynamic pressure Pdyn changes, dayside polar-cap convection and Harang region convection, and major disturbances of the magnetosphere-ionosphere system. The project will involve graduate student research, a postdoctoral researcher and a young woman scientist. It will also promote research partnerships between UCLA and the collaborative university, non-profit, and international organizations responsible for the operations of the various instruments and observational data sets that will be used.