Search Publications
Three frontside full halo coronal mass ejections with a nontypical geomagnetic response
Zhukov, A. N.; Rodriguez, L.; Schmieder, B. +9 more
Forecasting potential geoeffectiveness of solar disturbances (in particular, of frontside full halo coronal mass ejections) is important for various practical purposes, e.g., for satellite operations, radio communications, global positioning system applications, power grid, and pipeline maintenance. We analyze three frontside full halo coronal mas…
Studying geoeffective interplanetary coronal mass ejections between the Sun and Earth: Space weather implications of Solar Mass Ejection Imager observations
Webb, D. F.; Jackson, B. V.; Fry, C. D. +4 more
Interplanetary coronal mass ejections (ICMEs) are the primary cause of severe space weather at Earth because they drive shocks and trigger geomagnetic storms that can damage spacecraft and ground-based systems. The Solar Mass Ejection Imager (SMEI) is a U. S. Air Force experiment with the ability to track ICMEs in white light from near the Sun to …
A New Trend in Forecasting Solar Radiation Hazards
Heber, Bernd; Posner, Arik; Guetersloh, Stephen +1 more
Several international space agencies plan to send astronauts beyond low-Earth orbit in the coming decades to explore the Moon or other nearby planetary objects. Humans leaving the Earth's magnetosphere enter the solar wind, potentially exposing themselves to prompt solar energetic particle (SEP) events, which are sudden outbursts of energetic part…
Predictions of interplanetary shock arrivals at Earth: Dependence of forecast outcome on the input parameters
Dryer, M.; Fry, C. D.; Smith, Z. K. +1 more
Predictions of interplanetary shock arrivals at Earth are important to space weather because they are often followed by geomagnetic disturbances that disrupt human technologies. The success of numerical simulation predictions depends on the codes and on the inputs obtained from solar observations. The inputs are usually divided into the more slowl…
Real-time predictions of geomagnetic storms and substorms: Use of the Solar Wind Magnetosphere-Ionosphere System model
Kozyra, J.; Mays, M. L.; Horton, W. +1 more
A low-dimensional, plasma physics-based, nonlinear dynamical model of the coupled magnetosphere-ionosphere system, called Real-Time Solar Wind Magnetosphere-Ionosphere System (WINDMI), is used to predict AL and Dst values approximately 1 h before geomagnetic substorm and storm event. Subsequently, every 10 min ground-based measurements compiled by…
Forecasting maximum solar flare magnitudes from photospheric magnetograms
Sakurai, T.; Yamamoto, Tetsuya T.
The purpose of this paper is to forecast the maximum solar flare magnitude in an active region and its uncertainty from photospheric magnetic field data. We analyzed 21 flare samples covering X-ray flare magnitudes from A5.0 to X17.0. Photospheric magnetic parameters are obtained from vector and line of sight magnetograms observed with the Solar F…
Flare Irradiance Spectral Model (FISM): Flare component algorithms and results
Chamberlin, Phillip C.; Woods, Thomas N.; Eparvier, Francis G.
The Flare Irradiance Spectral Model (FISM) is an empirical model developed for space weather applications that estimates the solar irradiance at wavelengths from 0.1 to 190 nm at 1 nm resolution with a time cadence of 60 s. This is a high enough temporal resolution to model variations due to solar flares, where few accurate measurements at these w…
Major solar energetic particle events of solar cycles 22 and 23: Intensities above the streaming limit
Lario, D.; Aran, A.; Decker, R. B.
Large solar energetic particle (SEP) events constitute a serious radiation hazard to astronauts and spacecraft systems. It is essential to determine the highest particle intensities reached in SEP events, especially at the energies that pose serious risks to human health and spacecraft performance. It has been argued that the highest particle inte…
Modeling the arrival at Earth of the interplanetary shock following the 12 May 1997 solar event using HAFv2 and 3-D MHD HHMS models
Dryer, M.; Fry, C. D.; Sun, W. +3 more
The 12 May 1997 solar event is used to demonstrate the improvements that have been made in recent years in the accuracy of predicting, in the operational environment, the time of arrival at Earth of solar-caused interplanetary shocks. This event provides a simple test case because it was both well isolated in time from other events and well docume…
Flare Irradiance Spectral Model (FISM): Daily component algorithms and results
Chamberlin, Phillip C.; Woods, Thomas N.; Eparvier, Francis G.
The solar photon output from the Sun was once thought to be constant but is now known to vary considerably over timescales from seconds during solar flares to years due to the solar cycle. This is especially true in the wavelengths shorter than 208 nm (Al ionization edge), where measurements and models of the solar irradiance at these short wavele…