HR: 0800h
AN: SA51B-0239    [Abstracts]
TI: Continuous Time Model for the Dst Index
AU: Zhu, D
EM: m.balikhin@sheffield.ac.uk
AF: The University Of Sheffield, ACSE dep,The University Of Sheffield Mappin Street, Sheffield, S1 3JD United Kingdom
AU: * Balikhin, M A
EM: m.balikhin@sheffield.ac.uk
AF: The University Of Sheffield, ACSE dep,The University Of Sheffield Mappin Street, Sheffield, S1 3JD United Kingdom
AU: Billings, S A
EM: s.billings@sheffield.ac.uk
AF: The University Of Sheffield, ACSE dep,The University Of Sheffield Mappin Street, Sheffield, S1 3JD United Kingdom
AU: Wing, S
EM: simon.wingjhuapl.edu
AF: APL JHU,, Johj Hopkins rd., Laurel, MD 20723 United States
AB: We have used the NARMAX based system identification approach to deduce, directly from measurements of upstream magnetic field and solar wind bulk velocity, a continuous time differential relationship that governs the evolution of the Dst index. This relation has been used to deduce the analytical dependence of the ring current decay rate upon values of VBs and Dst. It is shown that this depends upon a number of previous values of the solar wind parameters and Dst. Therefore the assumption often used previously in empirical models that the magnetosphere is a first order Markov's system is not valid. We show that the continuous time relation derived can be used for a reliable forecast of the Dst index.
DE: 2722 Forecasting
DE: 2784 Solar wind/magnetosphere interactions
SC: SPA-Aeronomy [SA]
MN: 2004 AGU Fall Meeting