Observed and modeled coronal holes

Motivated by the need to validate coronal models against observations in a quantitative and objective way, we present preliminary results of our comparison between modeled and observed coronal holes. We combine relative intensity images of the solar corona and chromosphere with magnetograms to identify coronal hole regions on the Sun using an automated scheme and then compare them with modeled coronal holes, defined as the foot-points of magnetically open field lines. We use two different coronal models, a PFSS model and an MHD model, and run the computations using the same magnetic field data at the photospheric boundary.