HR: 14:20h
AN: SA23B-03 INVITED    [Abstracts]
TI: Sounding rocket observations of the small-scale neutral response in the E region to magnetospheric energy input at high latitudes
AU: * Larsen, M F
EM: mlarsen@clemson.edu
AF: Department of Physics & Astronomy, Clemson University, Clemson, SC 29634, United States
AB: Sounding rocket measurements have provided some of the most detailed observations of the small-scale response of the neutral lower thermosphere to magnetospheric energy input in the auroral zone. In January and February 2007, a series of such launches were carried out at Poker Flat, Alaska, during substorm conditions. The experiments built on results from launches in 2003 and earlier that were also carried out at that location. The 2007 observations provided a particularly good specification of the local forcing due to the ground-based support from the Poker Flat Incoherent Scatter Radar (PFISR), which was installed there recently. The rocket measurements provided wind profiles and the north-south gradients in the winds, as well as detailed in situ measurements of the electric fields, electron densities, particle energies, and neutral densities, and temperatures. Theoretical support for the experiments has included model runs with several different numerical models of the thermosphere-ionosphere system. The results suggest that the contribution to the overall Joule heating from small-scale structure in the electric fields can be significant, that the response of the winds in the lower thermosphere to auroral forcing is stronger than expected, and that the response of the winds to comparable forcing in different events can be significantly different. The available data will be summarized and the characteristics of the small-scale structure in the neutral response to auroral forcing will be described.
DE: 2407 Auroral ionosphere (2704)
DE: 2427 Ionosphere/atmosphere interactions (0335)
DE: 2435 Ionospheric disturbances
DE: 2437 Ionospheric dynamics
SC: SPA-Aeronomy [SA]
MN: 2007 Fall Meeting