CEDAR: Sprites as a Manifestation of Intense Electrodynamic Coupling of the Lower Atmosphere with the Ionosphere

Stanford University, Stanford CA

Investigators

Abstract

ATM-9908766 Inan, Umran A three year effort is proposed to theoretically investigate the energetics and potential global effects of the breakdown ionization regions associated with spectacular luminous glows occurring in clear air above thunderstorms (sprites). The purpose of the proposed research is to determine the temporal dynamics of energy transfer from lightning generated quasi-electrostatic fields into rotational, vibrational, electronic, and chemical energy of atmospheric molecules, resulting in optical (ultraviolet to infrared) emission, and to estimate the consequences of this deposited energy on the thermal and chemical balance of the D-region on a global scale. Recent experimental and theoretical findings indicate that the further development of understanding of energetics and phenomenology of sprite phenomena requires the inclusion of non-local and non-stationary effects of energetics runaway electrons on the dynamics and optical properties of the electrical breakdown above thunderstorms. The PIs will develop a comprehensive two-dimensional Monte Carlo particle model to treat effects of suprathermal runaway electrons on the development of the electrical breakdown in different altitude ranges. To answer outstanding scientific questions and to compare the model results with sprite observations the PIs will link their sprite models with available state-of-the-art D region chemistry, radiative transfer and infrared radiation models.