HR: 0830h
AN: SH21B-0150    [PDF]
TI: A Hybrid Heliospheric Modeling System: I. Background Solar Wind
AU: * Detman, T R
EM: Thomas.Detman@noaa.gov
AF: NOAA, Space Environment Center, 325 Broadway, Boulder, CO 80305 United States
AU: Arge, C N
EM: Nick.Arge@noaa.gov
AF: NOAA, Space Environment Center, 325 Broadway, Boulder, CO 80305 United States
AU: Arge, C N
EM: Nick.Arge@noaa.gov
AF: Cooperative Institute for Research in Environmental Sciences, University of Colorado, Boulder, CO 80303 United States
AU: Pizzo, V
EM: Vic.Pizzo@noaa.gov
AF: NOAA, Space Environment Center, 325 Broadway, Boulder, CO 80305 United States
AU: Smith, Z
EM: Zdenka.Smith@noaa.gov
AF: NOAA, Space Environment Center, 325 Broadway, Boulder, CO 80305 United States
AU: Dryer, M
EM: Murray.Dryer@noaa.gov
AF: NOAA, Space Environment Center, 325 Broadway, Boulder, CO 80305 United States
AU: Dryer, M
EM: Murray.Dryer@noaa.gov
AF: Exploration Physics International, Inc, Huntsville, Huntsville, AL 35806 United States
AU: Dryer, M
EM: Murray.Dryer@noaa.gov
AF: Geophysical Institute, University of Alaska, Fairbanks,, AK 99775 United States
AU: Fry, C D
EM: gfry@expi.com
AF: Exploration Physics International, Inc, Huntsville, Huntsville, AL 35806 United States
AB: We present results of project to improve geomagnetic forecasts using physics based models driven by solar observations. The Hybrid Heliospheric Modeling System (HHMS) is a Sun to Earth system composed of four models. The system is based on two existing (well used) physics-based models, connected by a new empirical model and followed by a second new empirical model. The physics-based models are a Source Surface (potential field) Current Sheet Model for the corona, and a time dependent 3D MHD solar wind model. The system is driven by a time series of photospheric magnetic maps composed from daily magnetograms. An empirical relationship between magnetic flux tube expansion factor and solar wind speed at 0.1 AU is the key element of the system. The solar wind model gives a predicted time series of MHD parameters at the Sun-Earth L1 Lagrange point and is verified against Omni, Wind or ACE satellite data, depending on the time period. The predicted time series at L1 is input to the second empirical (data based) model to predict the geomagnetic Ap index. Verification results for predicted solar wind and Ap for the years 1993 through 2002 are shown and compared with forecast skill of the official Ap forecasts that were issued by the NOAA Space Environment Center. Results show the HHMS should be able to provide some useful numerical guidance to the human forecasters in the declining phase of solar cycle 23, now underway.
DE: 2102 Corotating streams
DE: 2134 Interplanetary magnetic fields
SC: SPA - Solar and Heliospheric Physics [SH]
MN: 2003 Fall Meeting