Magnetospheric substorm energy dissipation in the atmosphere

摘要: Abstract The mechanisms of energy dissipation in the atmosphere for magnetospheric substorm sources are examined quantitatively, and height-integrated budget is determined average auroral conditions. Under steady-state conditions (1) at least 60% deposited by typical particle bombardment heats neutral atmosphere; about 11% maintains enhanced level ionization. Only 4% radiated visible, near i.r., u.v. spectral regions, which detectable ground-based airborne observations, 6% known to be medium far spectrum. Another 3% expended maintaining electron ion temperatures, bremsstrahlung radiation, long-wave radio emissions. This leaves 16% unaccounted for; it argued that bulk this must reside extreme radiation originating from highly excited atomic, molecular, ionic states. Both laboratory field evidence support suggestion. (2) Orthogonal electric fields dissipate substantial amount governed ionospheric conductivity profile. In fact, dissipated can exceed bombardment. About one-half goes into heating gas. (3) Plasma heat conduction a small source may have large spatial extent. Its principal effect gas, which, turn, raises temperature. OI(λ6300), spectroscopic signature SAR-ARCS.