GLOBAL AND LOCAL GEOSPACE MODELING IN ISTP

The objective of the University of Maryland ISTP theory project is the development of the analytical and computational tools, which, combine d with the data collected by the space and ground-based ISTP sensors, will lead to the construction of the first causal and predictive globa l geospace model. To attain this objective a research project composed of four complementary parts is conducted. First the global interactio n of the solar wind-magnetosphe re system is studied using three-dimen sional MHD simulations. Appropriate results of these simulations are m ade available to other ISTP investigators through the Central Data Han dling Facility (CDHF) in a format suitable for comparison with the obs ervations from the ISTP spacecrafts and ground instruments. Second, si mulations of local processes are performed using a variety of non-MHD codes (hybrid, particle and multifluid) to study critical magnetospher ic boundary layers, such as the magnetopause and the magnetotail. Thir d, a strong analytic effort using recently developed methods of nonlin ear dynamics is conducted, to provide a complementary semi-empirical u nderstanding of the nonlinear response of the magnetosphere and its pa rts to the solar wind input. The fourth part will be conducted during and following the data retrieval and its objective is to utilize the d ata base in conjunction with the above models to produce the next gene ration of global and local magnetospheric models. Special emphasis is paid to the development of advanced visualization packages that allow for interactive real time comparison of the experimental and computati onal data. Examples of the computational tools and of the ongoing inve stigations are presented.