Extreme bursts in the solar wind

The statistical characterization and prediction of bursts in solar activity and in the solar wind is a problem of great practical relevance in space weather physics. Here, we show that many of the apparent qualitative and quantitative differences in burst statistics between solar activity and solar wind variation during solar maximum can be resolved by considering extreme bursts. These are defined as peak-over-threshold events over the range of high thresholds for which their number decays as a power law. We find that the duration time and energy distributions of extreme bursts in the solar wind epsilon parameter are both threshold-independent. The distribution of times between extreme bursts in epsilon, however, depends markedly on threshold. Our results indicate that a signature of the solar activity appears in extreme bursts of the solar wind, while other features are likely governed by local plasma turbulence. Citation: Moloney, N.R., and J. Davidsen (2011), Extreme bursts in the solar wind, Geophys. Res. Lett., 38, L14111, doi: 10.1029/2011GL048245.