Forecasting of Emergence and Evolution of Active Regions by Local Helioseismology

We investigate the capability of local (time-distance) helioseismology for forecasting the emergence and development of major active regions and eruptive events, flares and CMEs, as well as for data-driven MHD modeling of CME events. The recent successful detection of several large solar active regions in acoustic travel-time signals before the emergence of active regions has opened a new opportunity for predicting major magnetic flux emergence events that are a primary source of solar flares and CMEs, from several hours to two days in advance. In addition, time-distance helioseismology has become a useful tool to map solar subsurface flow fields up to more than 20 Mm below the photosphere, and discovered strong shearing flows associated with flaring and CME activity. We discuss the current status of these measurements, their sensitivity and uncertainties, implementation for the SDO/HMI pipeline processing, and the data products available for the data-driven MHD modeling of solar eruptions.