Yesterday afternoon, May 18, the lava fountaining activity at Etna's Voragine crater (VOR) switched to a modest Strombolian activity, which continued to feed the lava overflow westward until late evening (see first image on the left, taken by the thermal camera at Bronte EBT). A second lava flow, fed by an effusive vent located near the lower of the two cones formed during the subterminal activity of July-August 2014, at the base of the Northeast Crater (NEC) cone, poured towards the northern part of the Valle del Bove in the direction of Monte Simone. This lava flow remained active until the early hours of today, 19 May (see second image on the left, taken by the high definition video camera at Monte Cagliato EMCH), even though, after midnight, the most advanced front no longer seemed fed. Shortly before midnight a modest increase in the volcanic tremor was observed and the clinometer, installed at Punta Lucia about 1 km NW of the NEC, again recorded a swelling of the summit area.
In the morning, the amplitude of the volcanic tremor showed a sudden increase and, at the same time, strong and almost continuous rumbles were heard in the inhabited centers in the eastern and southern sectors of the volcano. A dense eruptive cloud was formed, driven by the very strong eastward wind, which reached a height of just over 1 km above the top of Etna (see third image on the left, taken from Tremestieri Etneo, on the southern flank of the volcano ). Fallout of ash and lapilli occurred on the eastern flank, in an area immediately north of that affected by the pyroclastic fallout of the previous day. Observing the phenomenon was made difficult due to bad weather conditions; however the instrumental data - localization of the sources of the volcanic tremor and of the infrasonic signals - revealed a new paroxysmal episode at the VOR, confirmed a few hours later when the images, transmitted by the EBT thermal camera (Bronte), showed a new overflow towards the west, with a lava flow that overlapped with that of the previous evening. The eruptive activity continued until 09:00 local time, when a rapid decrease in the amplitude of the volcanic tremor was observed. At the time of publication of this update, the bad meteorological conditions strongly prevented the observation of the eruptive activity.
The eruptive activity is constantly monitored through visual, thermal, seismic, infrasonic and ground deformation surveillance systems.
ETNA UPDATE, 19 MAY 2016, 11:00 UTC
During the afternoon of 18 May 2016, the lava fountaining activity from Etna's Voragine crater passed into a modest Strombolian activity, which continued to feed the lava overflow toward west until the late evening (see first image at left, recorded by the thermal camera at Bronte , EBT). A second lava flow, which was emitted from an effusive vent located near the lower of the two conelets formed during the subterminal activity of July-August 2014, at the eastern base of the Northeast Crater (NEC), expanded into the northern portion of the Valle del Bove in the direction of Monte Simone. This lava flow remained active until the early morning hours of today, 19 May 2016 (see second image at left, recorded by the high-definition camera at Monte Cagliato, EMCH), though its most advanced front seemed to be stagnating after midnight. Shortly before midnight, there was a new increase in the volcanic tremor amplitude, and the clinometer installed at Punta Lucia, about 1 km northwest of the NEC, recorded renewed inflation of the summit area of the volcano.
In the morning, the volcanic tremor amplitude showed a sharp increase, and contemporarily loud and virtually continuous bangs were heard in populated areas to the east and south of the volcano. A dense eruption cloud was blown by the strong wind toward east at an altitude of little more than 1 km above the summit of Etna (see the third image at left, photographed from the village of Tremesteri Etneo, on Etna's south flank). Ash and lapilli fell onto the east flank of the volcano, in an narrow sector immediately adjacent to the north to area affected by the tephra fall on the previous day. Observation of the activity was difficult due to rather poor weather conditions; instrumental data - mainly the location of the volcanic tremor source and the origin of the infrasonic signals - indicate that a new paroxysmal episode was underway at the VOR. This was confirmed a few hours later when the images transmitted by the thermal monitoring camera EBT (Bronte) revealed a new lava overflow toward west, feeding a lava flow that descended on top of the lava of the previous evening. Eruptive activity was continuing at 09:00 local time, though the volcanic tremor amplitude was diminishing. At the time this update goes online, the inclement weather conditions are preventing observation of the activity going on at Etna's summit.
The eruptive activity is monitored continuously by the systems of video and thermal cameras, seismic stations and ground deformation