Modeling Interplanetary Expansion and Deformation of Coronal Mass Ejections With ANTEATR‐PARADE: Sensitivity to Input Parameters

Abstract

AbstractSpace weather predictions related to coronal mass ejections (CMEs) requires understanding how a CME is initiated and how its properties change as it propagates. Most predictions have been limited to the arrival time of a CME and include little to no information about the CME's internal properties. ANother Type of Ensemble Arrival Time Results‐Physics‐driven Approach to Realistic Axis Deformation and Expansion (ANTEATR‐PARADE) represents the most thorough description of the interplanetary evolution of CMEs in a highly computationally‐efficient model (Kay & Nieves‐Chinchilla, 2020, https://doi.org/10.1029/2020JA028911). presents the derivation of this model, where we have added an elliptical cross section to the original arrival time model ANTEATR and introduced internal magnetic and thermal forces that, combined with the drag, can alter the shape of the central axis and cross section. ANTEATR‐PARADE results include the transit time of CMEs, as well as the shape and size, propagation and expansion velocities, density, and magnetic field properties upon impact. We determine the dependence of each output on each of the ANTEATR‐PARADE input parameters. For a fast CME, we see that the parameterization of our thermal and magnetic models tends to be more important than the actual initial temperature or magnetic field strength. We extend to other CMEs and find that the sensitivities change with CME scale with thermal forces being more important for a weaker CME and magnetic forces being more important for a stronger CME. The most critical parameters for space weather predictions are the CME mass, the initial magnetic field strength, the adiabatic index, and the profile of the axial magnetic field strength.