Disclaimer: The following material is being kept online for archival purposes.
Although accurate at the time of publication, it is no longer being updated. The page may contain broken links or outdated information, and parts may not function in current web browsers.
A Technique of Forecasting Magnetic Field Properties of Interplanetary
Coronal Mass Ejection
Sara F. Martin
An experimental forecasting project was conducted during a 5 month interval
during 1999. Quantitative forecasts of 4 properties of the magnetic fields
of interplanetary coronal mass ejections (ICMEs) were made each time an
erupting or disappearing filament was recognized from daily images of the
Sun or observed in real time. The properties were (1) sign of helicity,
(2) direction of the axis in the front of the ICME assuming the form of
a helical flux rope, (3)pitch angle of the flux rope, and (4) direction
of the leading edge of the cloud excluding any initial draping field.
These forecasts are possible because of correlations of the chirality of
ICMEs with the chirality of their source coronal magnetic fields
and filaments (Rust and Kumar 1994, Solar Phys. 155, 69) and evidence that
ICMEs retain much of the original form of these source magnetic fields
at the Sun (Marubashi 1997, Geophys Mono Serie 99, p 147). The primary
objective in this forecasting project was to test the technique.
Most of the forecasts were issued 1-2 days after the eruptive event and
before possible recording of the anticipated ICMEs in space. A report
of "no forecast" was made in this same time interval if there was insufficient
chirality information immediatly available to make a forecast. Of
232 erupting or disappearing filaments during the 5 month interval, forecasts
were made on 158 (68%). The focus of the initial analyses is on approximately
20 major interplanetary events recorded by satellites during the forecasting
Organization: Helio Research
Address: 5212 Maryland Ave.
La Crescenta, CA91214
Above is background material for archival reference only.