HR: 1330h
AN: SH42A-0479 [PDF]
TI: Real-time Upstream Monitoring System: Using ACE Data to Predict the Arrival of Interplanetary
Shocks
AU: * Donegan, M M
EM: michelle.donegan@jhuapl.edu
AF: Johns Hopkins University Applied Physics Laboratory, 11100 Johns Hopkins Rd, Laurel, MD 20723 United States
AU: Wagstaff, K L
EM: wkiri@litech.org
AF: Jet Propulsion Laboratory, M/S 126-347
4800 Oak Grove Drive, Pasadena, CA 91109 United States
AU: Ho, G C
EM: george.ho@jhuapl.edu
AF: Johns Hopkins University Applied Physics Laboratory, 11100 Johns Hopkins Rd, Laurel, MD 20723 United States
AU: Vandegriff, J
EM: jon.vandegriff@jhuapl.edu
AF: Johns Hopkins University Applied Physics Laboratory, 11100 Johns Hopkins Rd, Laurel, MD 20723 United States
AB:
We have developed an algorithm to predict Earth arrival times for interplanetary (IP) shock events originating at the Sun.
Our predictions are generated from real-time data collected by the Electron, Proton, and Alpha Monitor (EPAM) instrument on
NASA's Advanced Composition Explorer (ACE) spacecraft. The high intensities of energetic ions that occur prior to and during
an IP shock pose a radiation hazard to astronauts as well as to electronics in Earth orbit. The potential to predict such
events is based on characteristic signatures in the Energetic Storm Particle (ESP) event ion intensities which are often
associated with IP shocks. We have previously reported on the development and implementation of an algorithm to forecast the
arrival of ESP events. Historical ion data from ACE/EPAM was used to train an artificial neural network which uses the
signature of an approaching event to predict the time remaining until the shock arrives. Tests on the trained network have
been encouraging, with an average error of 9.4 hours for predictions made 24 hours in advance, and an reduced average error
of 4.9 hours when the shock is 12 hours away.
The prediction engine has been integrated into a web-based system that uses real-time ACE/EPAM data provided by the NOAA
Space Environment Center (http://sd-www.jhuapl.edu/UPOS/RISP/ index.html.) This system continually processes the latest ACE
data, reports whether or not there is an impending shock, and predicts the time remaining until the shock arrival. Our
predictions are updated every five minutes and provide significant lead-time, thereby supplying critical information that can
be used by mission planners, satellite operations controllers, and scientists. We have continued to refine the prediction
capabilities of this system; in addition to forecasting arrival times for shocks, we now provide confidence estimates for
those predictions.
UR: http://sd-www.jhuapl.edu/UPOS/RISP/index.html
DE: 2114 Energetic particles, heliospheric (7514)
DE: 2139 Interplanetary shocks
DE: 7514 Energetic particles (2114)
SC: SPA - Solar and Heliospheric Physics [SH]
MN: 2003 Fall Meeting