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Solar Origins of August 26, 2018 Geomagnetic Storm: Responses of the Interplanetary Medium and Equatorial/Low-Latitude Ionosphere to the Storm
Akala, A. O.; Oyedokun, O. J.; Amaechi, P. O. +3 more
This study investigates the solar origins of August 26, 2018 geomagnetic storm and the responses of the interplanetary medium and equatorial/low-latitude ionosphere to it. We used a multiinstrument approach, with observations right from the solar surface to the Earth. Our results showed that the G3 geomagnetic storm of August 26, 2018 was initiate…
Assessing the Projection Correction of Coronal Mass Ejection Speeds on Time of Arrival Prediction Performance Using the Effective Acceleration Model
Vourlidas, Angelos; Papaioannou, Athanasios; Anastasiadis, Anastasios +1 more
White light images of coronal mass ejections (CMEs) are projections on the plane of sky (POS). As a result, CME kinematics are subject to projection effects. The error in the true (deprojected) speed of CMEs is one of the main causes of uncertainty to Space Weather forecasts, since all estimates of the CME time of arrival (ToA) at a certain locati…
Why are ELEvoHI CME Arrival Predictions Different if Based on STEREO A or STEREO B Heliospheric Imager Observations?
Temmer, Manuela; Möstl, Christian; Weiss, Andreas J. +9 more
Accurate forecasting of the arrival time and arrival speed of coronal mass ejections (CMEs) is an unsolved problem in space weather research. In this study, a comparison of the predicted arrival times and speeds for each CME based, independently, on the inputs from the two STEREO vantage points is carried out. We perform hindcasts using ELlipse Ev…
Multi-Instrument Investigation of the Impact of the Space Weather Events of 6-10 September 2017
Simi, K. G.; Amaechi, Paul O.; Akala, Andrew O. +3 more
We analyzed the space weather events of 6-10 September 2017 using the multi-instrument approach. We focused on the four X-class flares which emanated from the Active Region AR 12673 and the Ground Induced Currents hazard associated with the geomagnetic storm of 7-8 September 2017. The flare effect on the equatorial electrojet (EEJ) recorded on boa…
Harmonization of RBSP and Arase Energetic Electron Measurements Utilizing ESA Radiation Monitor Data
Miyoshi, Yoshizumi; Shinohara, Iku; Mitani, Takefumi +11 more
Accurate measurements of trapped energetic electron fluxes are of major importance for the studies of the complex nature of radiation belts and the characterization of space radiation environment. The harmonization of measurements between different instruments increases the accuracy of scientific studies and the reliability of data-driven models t…
A Multicomponent Magnetic Proxy for Solar Activity
Warren, Harry P.; Upton, Lisa A.; Floyd, Linton E.
We present a new, multicomponent magnetic proxy for solar activity derived from full disk magnetograms that can be used in the specification and forecasting of the Sun's radiative output. To compute this proxy we project Carrington maps, such as the synchronic Carrington maps computed with the Advective Flux Transport (AFT) surface flux transport …
Solar EUV-Enhancement and Thermospheric Disturbances
Briand, C.; Doerksen, K.; Deleflie, F.
The increase of energetic electromagnetic flux during solar flares and particle precipitation during geomagnetic activity are among the most important sources of neutral density disturbances to the Earth's thermosphere. However, disentangling the role of X and EUV radiation during solar flares is difficult due to the rarity of sufficiently isolate…
Warning Time Analysis From SEP Simulations of a Two-Tier REleASE System Applied to Mars Exploration
Posner, A.; Strauss, R. D.
The sudden exposure to energetic protons from solar energetic particle (SEP) events beyond the Earth's magnetosphere and en route to and from Mars can, in extreme cases, lead to acute radiation sickness, an impairing, mission-endangering condition for astronauts. Timely warnings of their impending occurrence may significantly reduce radiation expo…
Application of a Modified Spheromak Model to Simulations of Coronal Mass Ejection in the Inner Heliosphere
Pogorelov, Nikolai V.; Arge, Charles N.; Singh, Talwinder +1 more
The magnetic fields of interplanetary coronal mass ejections (ICMEs), which originate close to the Sun in the form of a flux rope, determine their geoeffectiveness. Therefore, robust flux rope-based models of CMEs are required to perform magnetohydrodynamic (MHD) simulations aimed at space weather predictions. We propose a modified spheromak model…
Reconstruction of Extreme Geomagnetic Storms: Breaking the Data Paucity Curse
Merkin, V. G.; Sitnov, M. I.; Roelof, E. C. +5 more
Reconstruction of the magnetic field, electric current, and plasma pressure is provided using a new data mining (DM) method with weighted nearest neighbors (NN) for strong storms with the storm activity index Sym-H < -300 nT, the Bastille Day event (July 2000), and the 20 November 2003 superstorm. It is shown that the new method significantly r…