Wed, 11/02/2016 - 3:00pm to 4:00pm
Morse 301
Space Science Seminar
Naomi Maruyama, NOAA

Development of the new Ionosphere-Plasmasphere-Electrodynamics (IPE) model toward cold plasma coupling in geospace

Abstract: Cold plasmas originating from ionosphere play an important role in magnetosphere, such as wave-particle interactions with electromagnetic ion cyclotron (EMIC) waves in the inner magnetosphere. Furthermore, a remarkable correlation has been observed between the inner edge of the outer radiation belt electrons and the innermost plasmapause location. Recent observations indicate that plasmaspheric plumes can play an important role in solar-wind-magnetosphere interactions by influencing dayside magnetic reconnection rates. However, one of the main challenges remains to be a lack of reasonable plasmaspheric models that can reproduce dynamical evolution of plasmaspheric plumes, plasmapause and refilling from the ionosphere.

We have developed a global three-dimensional ionosphere-plasmasphere-electrodynamics (IPE) model to understand the dynamical redistribution of the cold plasma between the ionosphere and plasmasphere, as well as the coupling to the Whole Atmosphere Model (WAM), an extension of the NOAA Global Forecast System (GFS) model.

The IPE model reproduces the ionospheric enhanced total electron content (TEC) plumes as frequently observed in the GPS TEC during geomagnetically active conditions (so called Storm Enhanced Density, SED). The SED plumes are transported into the cusp and over the pole due to the high latitude convection, which is characterized as Tongues of Ionizations (TOIs). The model captures the corresponding formation of the plasmaspheric drainage plume-like structure in the magnetospheric equatorial plane as reported in previous studies. The plumes gradually start to rotate around the earth, and the plasmasphere gradually refills from the ionosphere as the storm time convection weakens.

An effort has been underway to couple the IPE model to global magnetospheric MHD models such as OpenGGCM to evaluate an impact of the cold plasmas on the magnetosphere and its interaction with solar wind.