Free Energy Only vs Free Energy + Flares

Active regions that have recently produced an X- or M-Class flare (last 24 hours), are more likely to produce an event X-class, M-class, CME, Fast CME, or SPE in the near future. This is illustrated by the figure above from Falconer et al (2012).   This is especially the case for active regions with free-energy proxy LWLSG of 1 to a few times 104 G (need hyperlink to appropriate page for LWLSG), with increased forecast rates of up to a factor of 10, (or 0.2-0.3 events/day).   For active regions that have not produce a recent major flare, the forecasted event rate is slightly lower for forecasts based on free-energy proxy only.

 

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Figure Caption Forecast curves for X&M flares from free energy proxy only and free-energy proxy plus flare history.  

Left panels: Forecast curves based on free-energy proxy only.

Right panel: Forecast curves for recently flaring (red), recently non-flaring (blue), and free-energy proxy only (black). The fitted slope and uncertainty is given in the upper-left corner (free-energy proxy and recently flaring), or lower-right corner (non-recently flaring).   The uncertainty is the estimated uncertainty of the underlying rate from a limited sample.