The application of a new phenomelogical coronal mass ejection model to space weather forecasting

Recent work by the authors has produced a new phenomelogical forward model for coronal mass ejections (CMEs). This model, called the Tappin-Howard (TH) Model, takes advantage of the breakdown of geometrical linearity when CMEs are observed by white-light imagers at large distances from the Sun. The TH Model extracts three-dimensional structure and kinematic information on the CME using white light heliospheric image data alone. This information can be forward-projected to estimate the arrival time of the CME at 1 AU and the likelihood of impact with any point in the inner heliosphere, including the Earth. Hence the model can be used for CME-related space weather forecasting. We report on three mock trials that have been performed using the TH Model. These are already-studied events from 2003, 2004 and 2007 but we performed the trials assuming that they were being observed for the first time. We note times of observations and measurements and include an assumed data latency to accommodate for the time taken for data to be transmitted to the ground and transformed into a usable image. The earliest prediction was made 17 hours before impact and some early predictions were somewhat inaccurate (25 hours). Prediction accuracy improved with additional images and predicted arrival times reached differences within one hour for all three events. The most accurate predicted arrival time was only 15 minutes from the actual, and all three events obtained accuracies of the order of 30 minutes, well within the statistical uncertainties of the Model. Arrival speeds were also predicted to be very similar to the bulk plasma speed within the CME near 1 AU for each event, with the largest difference around 300 kms and the least only 40 kms. We offer this as a new method of space weather prediction that is both fast and more accurate than existing CME-related tools.