Kategorie: Climate Change

The volcano’s activity remains stable, but above background levels. No quakes were detected during the past 24-hour observation period. PHIVOLCS reported „Moderate emission of white steam-laden plumes that crept downslope before drifting to the general northwest was observed. Faint crater glow from the summit could be observed at night.“
„Continuous GPS monitoring indicate that the edifice is still inflated relative to July 2019 despite a period of general deflation since July-August 2020 and has been undergoing short-term inflation since November 2020. Deflation of the edifice with short-term inflation of the northwestern slopes since December 2020 has also been recorded by electronic tilt monitoring.“

The pyroclastic flow seen from the southwest (image: facebook.com/ashara.it)

Shortly after the previously reported major event, which was first seen as a large ash plume rising from the area, a new lava flow started to emerge from a vent in the summit area, descended on the Sciara del Fuoco and reached the sea. How large it is is still unclear, but the fact that it reached the shore quickly suggests it might have an important rate of lava flow.

It came as a result of what happened immediately before: According to the latest information from the National Institute of Geophysics and Volcanology (INGV) in Catania, explosive activity increased from 2.47 pm local time at the northern vents (on the side of Stromboli village). At 2.51 pm, this culminated in a pyroclastic flow that reached the coast and traveled out above water for about 1 km beyond the coastline (!), while the associated ash plume rose to 1.5-2 km height. Pyroclastic flows are deadly, turbulent hot avalanche of lava rock fragments of all sizes embedded in a mixture of turbulent gas and ash racing down slopes.

Video of the flow:



Likely, the reason for this flow was the sudden accumulation and destabilization of the upper crater area, resulting in a partial collapse. Monitoring instruments recorded significant deformation of the Sciara del Fuoco (a result of internal magma movement and release).

INGV also noted that following the main event, other, but smaller pyroclastic flows and rockfall episodes occurred in the following time, at 3.02, 3.04, 3.09, 3.13 and more until around 3.35 pm. Most of these also were accompanied by stronger explosions at the summit and produced modest ash plumes, but apparently did not extending beyond the shoreline.
To conclude from the observed data is that it seems that we witnessed the arrival of a significant batch of fresh magma in the upper conduits of the volcano. How large it is and how well supplied from deeper reservoirs will likely dictate how long the lava flow remains active and how activity will evolve in the near future. Previous lava flows on the Sciara observed in previous years were mostly rather short-lived, but often came in series during periods lasting several days to a few weeks. The best example and a likely candidate to compare probably could be the activity during the summer of 2019, characterized by two very large explosions in July and August and following periods of intermittent lava flows on the Sciara.

Thermal image of the lava flow on Stromboli volcano this afternoon (image: INGV Catania)

Ash plume from Stromboli this afternoon (image: Francesca Utano)

A significant event just occurred at Stromboli: friends of ours on the island just alerted us of a huge ash plume seen rising from the area of the Sciara del Fuoco at 14:51 local time.

What exactly happened is currently still unclear, but it could be – most likely – a larger rockfall event, or / and, possible in combination with a larger-than-usual explosion.
Check again later for more updates!

Over the past 1-2 weeks, activity at the volcano had already been increasing significantly, from low to high levels.
Note: It might come at least as a strange coincidence that Etna volcano on Sicily also had an unexpected eruption earlier today – although scientists do not have evidence for a direct link between the activity levels of the two volcanoes, local belief that there is one is strong, and cases like when both volcanoes produce something out of the usual are not the first time to be observed.

Activity index of Stromboli volcano during the past weeks (image: LGS)

Strong eruption accompanied by pyroclastic flows this morning (image: PVMBG)

The explosive eruption of the volcano continues at high levels.
Another vigorous eruption, lasting about 11 minutes, occurred at 04:48 local time this morning at the volcano.
According to PVMBG volcano observatory, a dense dark ash plume rose to estimated 6 km altitude and drifted east and south.
The explosion also triggered pyroclastic flows (gravity-driven mass flows) over the E-SE slopes reaching length of at least 3000 m.