Snapshot from the evolution of a CME as modeled using ELEvoHI in an ensemble approach (an animated version is also available). The model results are projected on to the plane of the ecliptic with the Sun. The dark gray area is the entity of all CME forecasts from the ensemble, while the two black curves indicate forecasts that gave best prediction of when the CME passed over two spacecraft MESSENGER (gray dot) and STEREO-B (blue dot). The blue line indicates direction where the Heliospheric Imager on STEREO-B observed the edge of the CME, a key input to the ensemble model. The size of the MESSENGER dot is modulated, after CME passage, to show the measured magnetic field, with scale shown by the pink dots in the upper part of the panel. Credit: Amerstorfer et al., 2018, Figure 5
Source: Space Weather

A new generation of space weather satellites is monitoring the launch and propagation of coronal mass ejections (CME) away from the Sun. Amerstorfer et al. [2018] contribute to the current debate by showing the value of ensemble modeling as a means to quantify the uncertainty in forecasts of CME propagation, and most importantly of CME arrival time at Earth. A better understanding of this uncertainty will help the operators of power grids and other infrastructure vulnerable to space weather to better prepare for adverse impacts following CME arrival. The authors also argue that a new generation of space weather monitors at the Lagrange L1 and L5 points will improve the accuracy of CME arrival forecasts. This is timely evidence as discussions in the United States and Europe are exploring how international collaboration can deliver space weather monitors to both L1 and L5.

Citation: Amerstorfer, T., Möstl, C., Hess, P., Temmer, M., Mays, M. L., Reiss, M. A., et al. [2018]. Ensemble prediction of a halo coronal mass ejection using heliospheric imagers. Space Weather, 16.

—Michael A. Hapgood, Editor, Space Weather

Text © 2018. The authors. CC BY-NC-ND 3.0
Except where otherwise noted, images are subject to copyright. Any reuse without express permission from the copyright owner is prohibited.