FG2. GGCM Modules and Methods

Co-chairs: John Dorelli (john<dot>dorelli<at>unh<dot>edu) and Michael Shay (shay<at>udel<dot>edu)

Goals

The overarching goal of this focus group is to understand the physics of collisionless magnetic reconnection on magnetospheric length scales (hundreds of ion inertial lengths). To this end, we have identified several broad questions to be addressed during the course :

• Q1: Can global resistive magnetohydrodynamics (MHD) codes accurately model magnetospheric reconnection?
  • Q1.1:
• Q2: How does the physics of collisionless reconnection observed in Particle-In-Cell (PIC) simulations scale up to reality?
• Q3: Can we extend global resistive MHD models to include microscale physics which is needed to accurately model reconnection?

The three questions Q1-Q3 are motivated by a currently popular approach to GGCM development known as the MHD spine approach. In the MHD spine approach, a global MHD model is used as the underlying computational "spine" of the GGCM, with non-MHD physics added (e.g., via coupling with another code) in regions of the simulation domain where the MHD approximation breaks down.