Monday, February 6, 2012

Mark Miesch and colleagues Ben Brown (Univeristy of Wisconsin-Madison), Nick Nelson and Juri Toomre (University of Colorado-Boulder), and Allan Sacha Brun (National Center for Scientific Research, France) our making progress studying and connecting the solar dynamo and magnetic flux emergence.

This work contributes significantly to HAO's Frontier 4, "Link Dynamos to Simulations of Flux Emergence". See article in NCAR's AtmosNews.

New simulations of a star much like the Sun image
New simulations of a star much like the Sun, but rotating five times faster, produce wreaths of magnetism in each hemisphere. The blue and red areas denote magnetic flux oriented toward the east and west, respectively. Faint lines trace the local direction of the three-dimensional magnetic field. (Simulation by Brown, Miesch et al.; visualization by Tim Sandstrom and Chris Henze, NASA.)

Because it’s such a computationally demanding task to simulate convective dynamos and flux emergence, most solar dynamo models to date have approximated convection and the BL process rather than depicting them directly. That’s the case with the groundbreaking solar dynamo model produced by NCAR’s Mausumi Dikpati and Peter Gilman, which was the first one to provide physics-based forecasting of future solar activity.

Several such models now generate realistic solar cycles, so it’s possible that the details of transient convection aren’t critical to the magnetic cycles. To get a better sense, Miesch and colleagues at several other institutions are drawing on NASA grants and NSF support and taking the next steps.