*************************** ** THE GEM MESSENGER ** *************************** Volume 16, Number 10 April 28, 2006 ---------------------------------------------------------------------------- MI Coupling Campaign -- Electrodynamics Working Group ---------------------------------------------------------------------------- From: Bill Lotko Joshua Semeter Please contact either of the above if you would like to participate in the following workshop: "The MIC Gap Region: Modeling and Phenomenology" The 2-3 RE spatial "gap" between the upper boundary of global ionospheric- thermospheric models and the lower boundary of global magnetospheric models is an important site of collisionless plasma transport. From observations we know that electromagnetic power flowing into this region, mostly from the magnetosphere, is transformed into field-aligned electrons and ion outflows and heat. The modification of the ionospheric conductivity by the associated energetic electron precipitation is included in most global models (via the "Knight relation" and a conductivity model), but collisionless Joule dissipation in the gap region is not usually included in the models, nor is dynamic feedback resulting from the heat flux transported into the magnetosphere by upward accelerated electrons and inertial loading by upflowing field-aligned ions. The mediating transport processes occur on spatial scales smaller than the grid sizes of the global models, so we face the challenge of developing models for subgrid processes using the dependent, large-scale variables available to us from the global models as causal drivers. We suggest that participants in this working group focus on one or more of the following issues for the 2006 workshop. Phenomenology, model development, and model validation are all relevant. 1) the current-voltage relation in regions of downward field-aligned current; 2) collisionless Joule dissipation and electron energization in Alfvenic regions; 3) models for ion transport in regions 1) and 2); and 4) ion outflow in the polar cap, essentially a polar wind. We are especially interested in ideas and strategies for developing subgrid models for use in global models and their validation. Observational studies and perspectives that enlighten development of such models are critical to success. +-------------------------------------------------------------------------+ |To subscribe GEM Messengers, send an e-mail to | | with the following command in the body of your e-mail message: | | subscribe gem | |To remove yourself from the mailing list, the command is: | | unsubscribe gem | | | |To broadcast a message to the GEM community, please contact Peter Chi at | | | |Please use plain text as the format of your submission. | | | |URL of GEM Home Page: http://www-ssc.igpp.ucla.edu/gem/Welcome.html | |Workshop Information: http://gem.rice.edu/~gem | +-------------------------------------------------------------------------+