Global Energy Flow in the Magnetosphere-Ionosphere System

Abstract

Planning for the OPEN (Origin of Plasmas in the Earth's Neighborhood) program in 1977-1978 was representative of early concepts to obtain a quantitative estimate of the energy flow through the magnetosphere-ionosphere system. The magnetosphere was the focus of those early planning discussions and the OPEN program was defined to address global issues of mass, momentum, and energy flow. The STEP program that we are celebrating at this conference is in many ways a direct evolution of the early work that led to the OPEN program. One of the main characteristics of those early discussions was the desire to obtain a global view of the magnetosphere. This pursuit of a global view not only has persisted through the evolution of OPEN through STEP, but it has been a consistent pursuit of space physics from its very beginnings. In fact, ground-based scientific activities prior to the space age had already recognized the importance of establishing observation networks designed to provide global views of the parameters being observed. In this paper, we review briefly both the early attempts at obtaining a global view of the magnetosphere and the initial arguments for obtaining a global measure of the energy flow through the magnetosphere. We then show, through realistic simulations, what now can be accomplished in the arena of measuring the global energy flow through the magnetosphere and its component parts. We discuss both qualitative and quantitative results, stressing the manner in which global observations play a vital role in furthering our understanding of the magnetosphere and its dynamics. Finally we present an example constructed from a video shown at the symposium that illustrates what might be seen of global magnetosphere dynamics with presently existing instrumentation.