The global core plasma model (GCPM) provides empirically derived core plasm
a density as a function of geomagnetic and solar conditions throughout the
inner magnetosphere. It is continuous in value and gradient and is composed
of separate models for the ionosphere, plasmasphere, plasmapause, trough,
and polar cap. The relative composition of plasmaspheric H+, He+, and O+ is
included in the GCPM. A blunt plasmaspheric bulge and rotation of the bulg
e with changing geomagnetic conditions is included. The GCPM is an amalgam
of density models intended to serve as a framework for continued improvemen
t as new measurements become available and are used to characterize core pl
asma density, composition, and temperature.