Adam Kellerman (UCLA) - The response of cosmic noise absorption to electron precipitation: A new method to infer energy input into the upper atmosphere over daily to climatic time scales.

October 2, 2019 3:30pm
MS 7124

Since the 1950’s, passive radiowave devices known as riometers have been monitoring cosmic noise emanating from distant stars and galaxies. When this radiowave energy enters the ionosphere it is absorbed by free electrons, and the energy is eventually deposited into the upper atmosphere through collisional processes. The presented work utilizes combined empirical and physics-based modeling approaches to investigate the relationship between precipitating electrons and cosmic-noise absorption. Presented is evidence that cosmic noise absorption responds to 10’s to 100’s of keV trapped and precipitating electrons. The presented work demonstrates that riometers may be used to remote sense energy-dependent electron precipitation into the atmosphere during periods of quiet to active geomagnetic activity, over long periods of time, and simultaneously across large spatial regions. The riometer-inferred precipitation may provide an important input to current atmospheric models, as these electrons precipitate to the ionospheric E and D regions, and to the upper mesophere, where they may lead to NOx production.