This program will determine how well geomagnetic storms can be predicted from magnetic polarities and orientation of disappearing filaments (DF) and soft x-ray arcades on the Sun. The PI will specifically address whether the topology of these fields is usually preserved upon eruption. The approach will involve: (1) a large data base of DFs, essentially independent of flares, for which the bounding polarities and geometrical orientations of preexisting filaments have been measured, (2) a determination of these properties for a data set of large-scale coronal x-ray arcades observed by Yohkoh, (3) the solar locations of the filaments and arcades into GSM coordinates so geometrical coupling effects influencing the occurrence rate and severity of storms can be accounted for, and (4) a superposed epoch analysis technique to compare different sets of the DF and arcade data with storm indices and a storm data set to determine which solar parameters are most geoeffective. The project results will improve understanding of solar mass ejecta characteristics that are most geoeffective, thereby enhancing the prediction of moderate to large storms, key to forecasting space weather.
