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The Correspondence Between Sudden Commencements and Geomagnetically Induced Currents: Insights From New Zealand
Forsyth, C.; Rae, I. J.; Smith, A. W. +6 more
Variability of the geomagnetic field induces anomalous Geomagnetically Induced Currents (GICs) in grounded conducting infrastructure. GICs represent a serious space weather hazard but are not often measured directly and the rate of change of the magnetic field is often used as a proxy. We assess the correlation between the rate of change of the ma…
Time-of-Arrival of Coronal Mass Ejections: A Two-Phase Kinematics Approach Based on Heliospheric Imaging Observations
Vourlidas, Angelos; Paouris, Evangelos
The forecasting of the Time-of-Arrival (ToA) of coronal mass ejections (CMEs) to Earth does not yet meet most Space Weather users' requirements. The main physical reason is our incomplete understanding of CME propagation in the inner heliosphere. Therefore, many ToA forecasting algorithms rely on simple empirical relations to represent the interpl…
A Machine Learning Approach to Predicting SEP Events Using Properties of Coronal Mass Ejections
Zhang, Ming; Zhao, Lulu; Torres, Jesse +1 more
Solar energetic particles (SEPs) can cause severe damage to astronauts and their equipment, and can disrupt communications on Earth. A lack of thorough understanding the eruption processes of solar activities and the subsequent acceleration and transport processes of energetic particles makes it difficult to forecast the occurrence of an SEP event…
Automated Detection of coronaL MAss Ejecta origiNs for Space Weather AppliCations (ALMANAC)
Morgan, Huw; Williams, Thomas
Alerts of potentially hazardous coronal mass ejection (CME) are based on the detection of rapid changes in remote observations of the solar atmosphere. This paper presents a method that detects and estimates the central coordinates of CME eruptions in Extreme Ultraviolet data, with the dual aim of providing an early alert, and giving an initial es…
The Frequency-Domain Characterization of Cosmic Ray Intensity Variations Before Forbush Decreases Associated With Geomagnetic Storms
He, Fei; Wang, Cong; Zhang, Xiaoxin +2 more
Nonrecurrent geomagnetic storms caused by Coronal Mass Ejection (CME) can induce serious impacts on space- and ground-based equipment. However, these nonrecurrent geomagnetic storms are hard to predict since CMEs are not periodic. Previous studies have shown that the variations of Cosmic Ray Intensity (CRI) before nonrecurrent storms may forebode …
Improving Multiday Solar Wind Speed Forecasts
Arge, C. N.; Henney, C. J.; Dayeh, M. A. +4 more
We analyze the residual errors for the Wang-Sheeley-Arge (WSA) solar wind speed forecasts as a function of the photospheric magnetic field expansion factor (fp) and the minimum separation angle (d) in the photosphere between the footpoints of open field lines and the nearest coronal hole boundary. We find the map of residual speed error…
A Parametric Study of Performance of Two Solar Wind Velocity Forecasting Models During 2006-2011
Srivastava, Nandita; Kumar, Sandeep
There is an increasing need for the development of a robust space weather forecasting framework. State-of-the-art MHD space weather forecasting frameworks are based upon the Potential Field Source Surface (PFSS) and Schatten Current Sheet (SCS) extrapolation models for the magnetic field using synoptic magnetograms. These models create a solar win…
CME Magnetic Structure and IMF Preconditioning Affecting SEP Transport
Lowrance, Patrick J.; Möstl, Christian; Guo, Jingnan +15 more
Coronal mass ejections (CMEs) and solar energetic particles (SEPs) are two phenomena that can cause severe space weather effects throughout the heliosphere. The evolution of CMEs, especially in terms of their magnetic structure, and the configuration of the interplanetary magnetic field (IMF) that influences the transport of SEPs are currently are…
A Multi-Purpose Heliophysics L4 Mission
Solanki, S. K.; Arge, C. N.; Henney, C. J. +13 more
The Earth-Sun Lagrangian point 4 is a meta-stable location at 1 AU from the Sun, 60° ahead of Earth's orbit. It has an uninterrupted view of the solar photosphere centered on W60, the Earth's nominal magnetic field connection to the Sun. Such a mission on its own would serve as a solar remote sensing observatory that would oversee the entire solar…
Evaluation of CME Arrival Prediction Using Ensemble Modeling Based on Heliospheric Imaging Observations
Dumbović, Mateja; Möstl, Christian; Weiss, Andreas J. +8 more
In this study, we evaluate a coronal mass ejection (CME) arrival prediction tool that utilizes the wide-angle observations made by STEREO's heliospheric imagers (HI). The unsurpassable advantage of these imagers is the possibility to observe the evolution and propagation of a CME from close to the Sun out to 1 AU and beyond. We believe that by exp…