Model Coupling Workshop Group Photo, Mesa Lab, Boulder, CO

*Abstracts*

**Model Coupling Science Agenda**

To improve the realism of modeling active region flux emergence and work towards simulating realistic solar eruptive events, HAO is hosted a workshop focusing on model coupling and data driven numerical simulations. Near surface layer radiation MHD simulations of active region formation driven by lower boundary conditions of emerging flux from a solar convective dynamo simulation are able to model sunspot and active region formation with realistic properties of the observed solar active regions. Methods of using observed time sequences of vector magnetograms to drive simulations of realistic solar eruptive events in the corona are being explored and developed. This workshop brought together modelers and observers to review recent results and to discuss methodologies and future directions. The following are some of the questions that were addressed:

1. What are the challenges of modeling realistic active region formation? How can model coupling be used to bridge the wide range of temporal and spatial scales (from global scale dynamo generation of active region flux to near surface layer fine scale evolution of sunspot formation) and the different physical regimes the problem encompasses?
2. How can coupled models and simulations help us interpret surface observations of active region evolution in terms of the subsurface structure of emerging flux, and in terms of deriving the boundary driving condition for coronal models of solar eruption?
3. Are photospheric observations of vector magnetic field evolution adequate to drive MHD models so that they can realistically model the magnetic field evolution of eruptive events? What additional observational data can be used to constrain and validate these models?
4. Many current CME simulations use ad-hoc boundary-driving to numerically construct a pre-eruptive coronal configuration and trigger its eruption. What are the adequate boundary conditions for such simulations, especially for the imposed electric fields? How can information derived from vector magnetic data or flux-emergence simulations be used to further increase their realism?

The aim was to encourage useful and effective discussions on this subject. The format of the workshop was informal consisting of oral presentations and open discussion sessions.

Conference Venue: NCAR Mesa Lab Auditorium

Workshop SOC:
Matthias Rempel (HAO/NCAR)
Yuhong Fan (HAO/NCAR)
Chaowei Jiang (Harbin Institute of Technology, Shenzhen, China)
Maria Kazachenko (SSL/UC Berkeley, CU/NSO)
Mark Cheung (LMSAL)
Mark Linton (NRL)
Tibor Toeroek (PSI)