HR: 1330h
AN: SH42B-0529 [PDF]
TI: Time Evolution of Coronal Holes and Their Impact on the Solar Wind
AU: * Holzer, T E
EM: holzer@ucar.edu
AF: NCAR/HAO, 3450 Mitchell Lane, Boulder, CO 80301 United States
AU: de Toma, G
EM: detoma@ucar.edu
AF: NCAR/HAO, 3450 Mitchell Lane, Boulder, CO 80301 United States
AU: Arge, C N
EM: Nick.Arge@noaa.gov
AF: NCAR/HAO, 3450 Mitchell Lane, Boulder, CO 80301 United States
AU: Arge, C N
EM: Nick.Arge@noaa.gov
AF: NOAA/SEC, 325 South Broadway, Boulder, CO 80305 United States
AU: Arge, C N
EM: Nick.Arge@noaa.gov
AF: University of Colorado/CIRES, 216 UCB, Boulder, CO 80309-0216 United States
AU: Burkepile, J T
EM: iguana@ucar.edu
AF: NCAR/HAO, 3450 Mitchell Lane, Boulder, CO 80301 United States
AB:
Coronal holes, which can be defined as open magnetic field regions on the Sun, are the source of high-speed streams and
possibly slow wind and thus play an important role in nature and structure of the solar wind/heliosphere. Over the last
decade, significant progress has been made in our ability to predict ambient solar wind conditions days in advance using a
number of different models that vary widely in their sophistication (e.g., MHD and Potential Magnetic Field Source Surface
Models) but all of which are driven by observations of the photospheric magnetic field in the form of synoptic maps. These
ambient solar models based on extrapolation from photospheric magnetic fields are limited and cannot duplicate the complexity
of the solar wind during periods of transient wind. However, a very recent comprehensive study by Arge et al. has shown that
significant discrepancies often occur between model predictions and observations
after transient wind has completed its passage past Earth and the observed solar wind has returned to ambient/background
conditions (i.e., when the model is expected to resume performing well). Such discrepancies can persist for 2 to 3 days after
the passage of the transient. To understand the origin of these differences, we will use coronal observations at time of
CMEs to study variations in the pattern of coronal holes at the Sun. Our goal is to investigate if changes in coronal holes
(probably not visible in photospheric field synoptic maps) can be responsible for the changes seen at 1AU.
DE: 2169 Sources of the solar wind
DE: 7509 Corona
DE: 7511 Coronal holes
DE: 7524 Magnetic fields
SC: SPA - Solar and Heliospheric Physics [SH]
MN: 2003 Fall Meeting