Estimating the Global Solar Magnetic Field Distribution Using ADAPT

Estimation of the global solar photospheric magnetic field distribution is currently difficult, since only approximately half of the solar surface is magnetically observed at any given time. With the solar rotational period relative to Earth at approximately 27 days, these global maps include observed data that are more than 13 days old. Data assimilation between old and new observations can result in spatial polarity discontinuities that result in significant monopole signals. To help minimize these large discontinuities and to specify the global state of the photospheric magnetic flux distribution as accurately as possible, we have developed the ADAPT (Air Force Data Assimilative Photospheric flux Transport) model, which is comprised of a photospheric magnetic flux transport model that makes use of data assimilation methods. The ADAPT transport model evolves the solar magnetic flux for an ensemble of realizations using different model parameter values, e.g., for rotational, meridional, and super-granular diffusive transport processes. In this presentation, the ADAPT model and the data assimilative methods used within it will be reviewed. Coronal, solar wind, F10.7, and EUV model predictions based on ADAPT global photospheric magnetic field maps as input will be discussed.