HR: 11:00h
AN: SA31B-03    [PDF]
TI: Comparisons of Solar EUV Irradiance Variations from Measurements, Models and GUVI Terrestrial Far Ultraviolet Dayglow Observations
AU: * Lean, J L
EM: jlean@ssd5.nrl.navy.mil
AF: E. O. Hulburt Center for Space Research, Naval Research Laboratory, Washington, DC 20375 United States
AU: Strickland, D J
EM: dstrick@cpi.com
AF: Computational Physics Inc, 8001 Braddock Road, Springfield, VA 22151 United States
AU: Meier, R R
EM: meier@uap2.nrl.navy.mil
AF: E. O. Hulburt Center for Space Research, Naval Research Laboratory, Washington, DC 20375 United States
AU: Christensen, A B
EM: Andrew.B.Christensen@aero.org
AF: Space Science Applications Laboratory, Aerospace Corporation, El Segundo, CA 90245 United States
AU: Woods, T N
EM: tom.woods@lasp.colorado.edu
AF: Laboratory for Atmospheric and Space Physics, University of Colorado, Boulder, CO 80309 United States
AU: Eparvier, F G
EM: eparvier@colorado.edu
AF: Laboratory for Atmospheric and Space Physics, University of Colorado, Boulder, CO 80309 United States
AU: McMullin, D
EM: mcmullin@nrl.navy.mil
AF: E. O. Hulburt Center for Space Research, Naval Research Laboratory, Washington, DC 20375 United States
AU: Judge, D L
EM: judge@usc.edu
AF: Space Science Center, University of Southern California, Los Angeles, CA 90007 United States
AB: During mid 2002, solar EUV irradiance changed slowly as the Sun rotated on its axis, and increased episodically in association with multiple solar flares. As the TIMED/SEE and SOHO/SEM instruments monitored the solar EUV irradiance changes directly, TIMED/GUVI observed concurrent fluctuations in the Earth's far UV dayglow. An integrated measure of solar EUV electromagnetic energy shortward of 45 nm, called QEUV, is derived from the GUVI dayglow measurements and compared with the directly measured EUV energy and estimates from four different variability models, each summed shortward of 45 nm. The values derived from the GUVI dayglow observations agree well with both the absolute values and solar rotation modulation of the NRLEUV model, and do not support recent suggestions that the solar EUV irradiances estimated by the model of Hinteregger et al. be increased by a factor of four, nor even a factor of two. High resolution (hourly) temporal structure present in QEUV tracks closely the increase in EUV energy during solar flares, monitored by SOHO/SEM, and documents a highly radiatively coupled solar-terrestrial system.
DE: 0358 Thermosphere--energy deposition
DE: 7537 Solar and stellar variability
DE: 7538 Solar irradiance
SC: SPA - Aeronomy [SA]
MN: 2003 Fall Meeting