April 28, 2017, 1:00 pm - 2:00 pm

April 28, 1:00 pm - 2:00 pm

Using Simple Models to Describe CMEs from Sun to Earth

Christina Kay (GSFC/671)

Coronal mass ejections (CMEs) tend to drive the strongest space weather events at Earth and through the rest of the heliosphere. Predicting the effect that a CME may have requires understanding if and when a CME will impact and the CME properties upon impact. The severity of a storm depends on the speed of a CME, and the strength and orientation of its magnetic field, which can be very sensitive to the position and orientation of a CME. Rather than using sophisticated, yet complex and computationally intensive models to simulate the coronal dynamics of a CME, we present a pair of simple, highly computationally efficient models that determine the coronal dynamics of a CME and its in situ magnetic profile. Forecasting a CME's Altered Trajectory (ForeCAT, Kay et al. 2015) simulates the coronal deflection and rotation of a CME using the magnetic tension and magnetic pressure gradients from the background solar magnetic field. The ForeCAT In situ Data Observer (FIDO, Kay et al. 2017) uses the CME latitude, longitude, and orientation from a ForeCAT simulation and applies a force-free flux rope to the CME shape, which it then propagates over a fixed observer, yielding a synthetic in situ magnetic profile that can be directly compared with observations. We will present results for a series of CMEs erupting from a single active region during 13-16 February 2011, as well as a new study of 45 Earth-impacting CMEs occurring between 2007 and 2014.