"Larger than normal" is defined here as Strombolian explosions occurring at irregular intervals lasting from 5 minutes to >1 hour, with explosions consisting of short (i.e., less than 1 minute) bursts of incandescent lava fragments, ash, or both together. Part of the "normal" activity is characterized as well by the presence of active lava (small lava ponds) in one or more vents. Activity departing from "normal" is defined as prolonged Strombolian bursts or fountaining (>1 minute), strong explosions with block and bomb ejection onto Pizzo sopra la Fossa or beyond, pyroclastic flows (glowing avalanches), and emission of lava flows.
More important eruptions are briefly described to give an impression of what may occur, although rarely, at Stromboli (see sample: 1930 eruption, below). For a comprehensive picture of Stromboli's long-term activity (i.e., in the course of several years), the period 1985-1995 is summarized (including personal accounts of seven visits in six years). This may be taken as largely representative, although events on a scale comparable to that of the 1919 or 1930 eruptions did not occur during this period.
Stromboli, a small island north of Sicily, is one of the most active volcanoes in the world and famous for its normally small, but regular explosions throwing out glowing lava from several vents inside its summit crater. This activity has been going on for at least 2000 years, as long as there is written memory of the activity, which Stromboli lended its name to, the so-called strombolian activity