HR: 1340h
AN: SH23A-0334 [Abstracts]
TI: Forecasting the Intensity of Magnetic Storms Caused
by N→S Type of Interplanetary Magnetic Clouds
AU: * Lepping, R P
EM: Ronald.P.Lepping@nasa.gov
AF: NASA/GSFC, Laboratory for Solar and Space Physics, NASA/GSFC, Code 612.3, Greenbelt, MD 20771
United States
AU: Wu, C
EM: wuc@cspar.uah.edu
AF: NASA/GSFC, Laboratory for Solar and Space Physics, NASA/GSFC, Code 612.3, Greenbelt, MD 20771
United States
AU: Wu, C
EM: wuc@cspar.uah.edu
AF: CSPAR/ University of Alabama in Huntsville, 301 Sparkman Dr NW, Huntsville, AL 35899
United States
AU: Berdichevsky, D B
EM: DBerdich@pop600.gsfc.nasa.gov
AF: NASA/GSFC, Laboratory for Solar and Space Physics, NASA/GSFC, Code 612.3, Greenbelt, MD 20771
United States
AU: Berdichevsky, D B
EM: DBerdich@pop600.gsfc.nasa.gov
AF: L3 Goverment Service Inc., 1801 McCormick Dr., Suit 170, Largo, MD 20774
United States
AU: Narock, T
EM: Narock@lepimp.gsfc.nasa.gov
AF: NASA/GSFC, Laboratory for Solar and Space Physics, NASA/GSFC, Code 612.3, Greenbelt, MD 20771
United States
AU: Narock, T
EM: Narock@lepimp.gsfc.nasa.gov
AF: L3 Goverment Service Inc., 1801 McCormick Dr., Suit 170, Largo, MD 20774
United States
AB:
A scheme developed to forecast in near real time the value of
minimum Dst, and its time of occurrence, during a magnetic storm caused by the passage of a N→S type of magnetic
cloud (MC) is described. [N→S refers to the Bz component of the interplanetary magnetic field within a MC going
from north (+) to south (-) in GSE coordinates.] This type of MC is expected to be most common starting with solar cycle 24
(i.e, year 2007). The scheme uses a program recently developed to automatically identify MCs and cloud-like regions of any
type passing Earth. The MC identification program can use real-time magnetic field and plasma data from a spacecraft
upstream of Earth, such as ACE, in a mode that enables prediction of min Bz in the latter part of the MC from the measured
earlier portion of that MC using the latest version of our MC model parameter fitting scheme*. The original identification
scheme has been augmented to determine handedness and to more accurately estimate the occurrence time of the MC's front
boundary and center time. Previously developed relationships between Bzmin and VBzmin of the solar wind with Dst
are utilized in the forecasting, where V is the plasma speed at minimum Bz which is close to the average speed of the MC.
The overall forecasting scheme has been extensively tested using data from previously observed WIND N→S type MC
regions, augmented with S→N type of MCs made to look like N→S types (to improve statistics), giving a
total of 27 test MCs, after some quality editing. From this it was determined that typically, for prediction purposes,
input field data from as much as the first 70% of a MC must be used to acceptably reproduce model parameter-values that
result when the full 100% duration of the MC is used. The overall scheme and its test results will be described in detail.
*Reference: Lepping et al., J. Geophys. Res., vol. 95, 11957, 1990.
DE: 2111 Ejecta, driver gases, and magnetic clouds
DE: 2134 Interplanetary magnetic fields
DE: 2788 Magnetic storms and substorms (7954)
SC: SPA-Solar and Heliospheric Physics [SH]
MN: Fall Meeting 2005