Dartmouth Events

Title: "The Role of High-Power Ionospheric Modification in Advancing
Ionospheric/Thermospheric Research"

Abstract: Ionospheric modification (heating) has been used to explore nonlinear phenomena in space plasmas systematically for about 50 years.  The recent completion of the HAARP facility in Gakona, Alaska, with effective radiated power in the gigawatt range, expanded the range of phenomena accessible to investigators. Not only "artificial" but also natural processes including ionospheric chemistry, energetics, and transport can be studied with heating, sometimes in regimes that otherwise would be inaccessible. True experiments (as opposed to mere observations) can be performed with heating, promoting rapid progress
and even closure of certain key questions in aeronomy. In this seminar, four applications of ionospheric modification will be examined. These include studies of heater-induced E-region field aligned irregularities, electron acceleration and secondary ionization in the F region, neutral atmospheric diagnostics using artificial periodic inhomogeneity (API), and radar imaging of natural sporadic E layers. In each case, ionospheric heating provided incisive information that would have been
difficult to obtain by other means.