HR: 15:25h
AN: SA33A-08    [Abstracts]
TI: Improvements in modeling thermospheric densities using a new Schumann-Runge Continuum index
AU: * Tobiska, W
EM: ktobiska@spacenvironment.net
AF: Space Environment Technologies, 1676 Palisdes Dr., Pacific Palisades, CA 90272 United States
AU: Bowman, B R
EM: Bruce.bowman@peterson.af.mil
AF: US AFSPC/XPY, Peterson AFB, Colorado Springs, CO 80914 United States
AB: Major improvements in solar irradiance specification are reported with the development of a Schumann-Runge Continuum index for use in empirical thermospheric density models. The far ultraviolet (FUV) Schumann-Runge Continuum (SRC) energy, which has a unit optical depth in the lower thermosphere, has historically not been included in Jacchia and MSIS type models. The SRC is the main source of thermospheric molecular oxygen dissociation from photoabsorption. Proxies for the solar extreme ultraviolet (EUV) irradiances alone have been used in these types of models although the energy in the SRC contributes to lower thermospheric heating and, subsequently, density changes in higher layers. We show major improvements in satellite drag modeling by incorporating a SRC index derived from UARS, TIMED, and SORCE observations in addition to traditional EUV indices such as F10.7 and E10.7. We describe the formation of the new solar index, ESRC, that quantifies energy in the FUV Schumann-Runge Continuum and report on its use for improving thermospheric density specification.
DE: 3369 Thermospheric dynamics (0358)
DE: 7934 Impacts on technological systems
DE: 7959 Models
DE: 7974 Solar effects
SC: SPA-Aeronomy [SA]
MN: Fall Meeting 2005