LAUSR

In the present paper, solar magnetograms provided by the Helioseismic and Magnetic Imager (HMI) on-board Solar Dynamics Observatory (SDO) spacecraft are used to identify active regions automatically by thresholding the line-of-sight component of the solar magnetic field. The flare potential of the regions is predicted by locating potential active regions with strong-gradient polarity inversion lines (SPILs) and estimating 18 physically relevant parameters of these regions. In particular, parameters of interest include the sum of north-south gradients, sum of east-west gradients, length of SPIL, and total integrated magnetic flux. For deterministic prediction of flares, analysis for thresholding of single parameters and different combinations, which include up to 4 parameters, are presented and compared. If the false alarm rate does not exceed 10% (20%), the probabilities for correct prediction of X-ray flares of class M and greater, M5 and greater, and X in the 24 h window are 71% (86%), 84% (96%), and 94% (100%), respectively. These probabilities are for the best 4-parameter technique found. A technique for probabilistic forecasting was also developed. These deterministic and probabilistic techniques will be implemented in a revised version of the flare warning program, Flarecast, which will be operational in the Australian Space Forecast Centre.