Improving CME evolution and arrival predictions with AMR and grid stretching in Icarus by Tinatin Baratashvili et al. on Thursday 24 November

Coronal Mass Ejections (CMEs) are one of the main drivers of disturbances in

the interplanetary space. Strong CMEs, when directed towards the Earth, cause

geo-magnetic storms upon interacting with the magnetic field of the Earthand

can cause significant damage to our planet and affect everyday life. As such,

efficient space weather prediction tools are necessary to forecast the arrival

and impact of CME eruptions. Recently, a new heliospheric model Icarus was

developed based on MPI-AMRVAC, which is a 3D ideal MHD model for the solar wind

and CME propagation, and it introduces advanced numerical techniques to make

the simulations more efficient. A cone model is used to study the evolution of

the CME through the background solar wind and its arrival and impact at Earth.

Grid stretching and AMR are combined in the simulations by using multiple

refinement criteria. We compare simulation results to the EUFHORIA model. As a

result, the simulations were sped up by a factor of 17 for the most optimal

configuration in Icarus. For the cone CME model, we found that limiting the AMR

to the region around the CME-driven shock yields the best results. The results

modelled by the simulations with radial grid stretching and AMR level 4 are

similar to the results provided by the original EUHFORIA and Icarus simulations

with the 'standard' resolution and equidistant grids. The simulations with 5

AMR levels yielded better results than the simulations with an equidistant grid

and standard resolution. Solution AMR is flexible and provides the user the

freedom to modify and locally increase the grid resolution according to the

purpose of the simulation. The advanced techniques implemented in Icarus can be

further used to improve the forecasting procedures, since the reduced

simulation time is essential to make physics-based forecasts less

computationally expensive.

arXiv: http://arxiv.org/abs/http://arxiv.org/abs/2211.12867v1