HR: 1340h
AN: SA33A-1059 [Abstracts]
TI: The Effect of Downward Electron Heat Flow and Electron Cooling Processes in the High- Latitude Ionosphere
AU: * David, M
EM: michael.david@aggiemail.usu.edu
AF: Utah State University, Center for Atmospheric and Space Sciences, 4405 Old Main Hill,
Logan, UT 84322-4405, United States
AU: Schunk, R W
EM: schunk@cc.usu.edu
AF: Utah State University, Center for Atmospheric and Space Sciences, 4405 Old Main Hill,
Logan, UT 84322-4405, United States
AU: Sojka, J J
EM: fasojka@sojka.cass.usu.edu
AF: Utah State University, Center for Atmospheric and Space Sciences, 4405 Old Main Hill,
Logan, UT 84322-4405, United States
AB:
The electron energy balance in the terrestrial ionosphere is affected by numerous local heating and cooling
processes, as well as transport processes. The thermal electrons gain energy from photoelectrons, auroral
electrons, hot thermal ions, and a downward flow of heat from high altitudes. The thermal electrons lose energy
in elastic collisions with ions and neutrals (N2, O2, O, He, H), rotational excitation of N2 and
O2, vibrational excitation of N2 and O2, excitation of the fine structure level of atomic oxygen, and
electronic excitation of atomic oxygen. The transport processes include thermal conduction and thermoelectric
heat flow.
Recently, new cooling rates have been calculated that are substantially different from those in current use, which
are more than thirty years old. We will present model simulations showing the impact these new cooling rates
have on the electron temperatures and ion densities in the mid- and high-latitude ionosphere.
Additionally, recent work based on DMSP satellite data has made it possible to estimate the proper values of the
downward electron heat flow in the polar cap. This important parameter has typically been ignored in the past,
due to a lack of measurements. We present the results of model simulations driven by the new estimates of the
heat flow.
DE: 2400 IONOSPHERE (6929)
DE: 2443 Midlatitude ionosphere
DE: 2467 Plasma temperature and density
DE: 2736 Magnetosphere/ionosphere interactions (2431)
SC: SPA-Aeronomy [SA]
MN: 2007 Fall Meeting