23 Oct La Palma eruption update 23rd october 2021: New lava stream observed to the south

Currently, a period of the redistribution of active lava flows seems to be taking place around the volcano, with the flows affecting La Laguna appearing to have almost stopped and receiving a smaller contribution of lava than previous days. As such, the area affected by lava flows has only increased by 3.4 hectares relative to the previous days, with 849 hectares now estimated to be covered. However, the progress of this flow is still being heavily monitored, especially its potential path in relation to if it would pass to the north or the south of La Laguna Mountain. Multiple small partial collapses in the main lava emission vent (which has formed a conelet of welded pyroclasts on the main cone) are thought to be the reason for this redistribution, as well as the development of lava tubes. In the afternoon, a new lava flow to the south of the main cone upstream of Corazoncillo was observed, although its progress is slow, in part because it entrains a lot of the ash and pyroclasts deposited in this area as it moves, which increases its viscosity.

22 Oct La Palma eruption update 22nd october 2021: Forward advance of lava has slowed

The front of the active lava flows in La Laguna to the north of the flow field are currently practically stopped, although there still remains a high flux of lava feeding these flows, which is leading to their widening and thickening. Nonetheless, the evacuation ordered on the 20th October remains in place. The latest damage assessment puts 845 hectares of land affected by the lava flows, and according to the land registry, 1,280 buildings have been damaged or destroyed including 1,030 residential buildings. However, data from Copernicus EMS estimates a much larger number of buildings affected. 258 hectares of agricultural land has been affected so far, including 144 hectares of banana plantations.

21 Oct La Palma eruption update 21st october 2021: The lava flow field is now up to 2,900 m wide

The two active streams to the north have grown and coalesced and appear to be travelling to the SW of La Laguna Mountain. However, it cannot yet be ruled out that their growth and the changing topography may mean the flow travels northwards in the future, which is the fear that prompted the preventative evacuation on the afternoon of the 20th October. The flow to the north closest to the sea remains at 80 m from the cliff, and there have been minimal contributions to this flow in the last 24 hours. Regarding eruptive activity, there are currently five active vents, four strombolian vents in the main cone, and one vent showing only lava emission. The area affected is now 825 hectares, with the lava flow field now 2,900 m across at its widest point.

20 Oct La Palma eruption update 20th october 2021: Further preventative evacuations ordered

The two active lava flows to the north of the flow field continue to be heavily monitored as they both continue to advance. The further south of the two, which travels to the south of La Laguna Mountain, is only 80 m from the coast, although it moves forwards only incrementally. The furthest north flow has begun to affect the urban centre of La Laguna, including the petrol station at La Laguna crossing, causing a large fire. Due to the possible future path of this flow, preventative evacuations were ordered in the afternoon for people in Las Martelas, Marina Alta, Marina Baja, Condesa and Cuesta Zapata, totally around 150 people bringing the total number of evacuees to 6,600, not including 400 evicted tourists that were transferred to Tenerife at the start of the eruption. This flow is currently being fed by a relatively large flux of lava, and the new Strombolian vent that opened on the afternoon of the 19th October remains active. Elsewhere, findings of underwater studies have been published today, and include that up to 11 ha of underwater ravines have been filled by the lava flows, and a decrease in fluorescence (a proxy for certain marine organisms) of 48% in the first 150 m depth of the water column has been seen.

19 Oct La Palma eruption update 19th october 2021: The northern lava front is 100 m from the coast

The self-protection recommendation announced yesterday for the population of El Paso, in the face of continuing unfavourable air quality with respect to PM10 concentrations, has been maintained. Residents should stay indoors as much as possible, particularly between 2pm-9pm local time, and wear an FFP2 mask if they must go outside. The active lava flows continue to advance slowly; the flow south of La Laguna Mountain is around 100 m from the coast, moving at 3-5 m per hour, and the northernmost flow is currently heading for the centre of La Laguna, although its path is less certain. Between the main cone and the ash vent that opened on the 16th October, a new vent opened in the afternoon, initially showing phreatomagmatic activity before transitioning into Stromolian activity. More findings from the chemical analysis of the lava have been published, showing the evolution from more differentiated to more primitive magma occurred contemporaneously with the hiatus of surface activity on the 27th September.

18 Oct La Palma eruption update 18th october 2021: New advisories to the population due to poor air quality

The eruption continues as in the previous days, with a Strombolian mechanism with a predominant effusive phase and a weaker explosive phase. More explosive activity continues to be concentrated in multiple vents within the main cone, and the effusive outlet is seen as a stepped lava channel that runs down the northern flank. The ash emission vent on the SE flank which reactivated on the 16th October continues intermittently. The active lava flow to the south of La Laguna Mountain, closest to the coast, has slowed to 2 m per hour and is currently 160 m from the coast. Elsewhere, advance of the flow front located just above La Laguna has largely stalled for the moment, although the flows continue to widen and thicken. Between 2pm-9pm local time, it was advised in El Paso that the population stay indoors due to unfavourable PM10 concentrations. This was due to the influence of the Saharan air mass, the ash from the volcano, and also the persistence of a low thermal inversion, which is expected to persist until the 22nd October. However, ash dispersion was more favourable than previous days with respect to the operation of La Palma airport.

17 Oct La Palma eruption update 17th october 2021: The airport continues to be affected by ash

The eruption continues to show a strombolian mechanism with mixed explosive and effusive phases, with the effusive phase remaining the stronger of the two currently. The main active lava flows are the two branches to the north of the original flows. The southern branch of this flow has surpassed La Laguna Mountain to the south and is currently approximately 200 m from the coast. In the event that this flow reaches the sea, PEVOLCA confirmed a confinement of the population in Todoque would be ordered, similar to when the first flows reached the sea. The northern branch of the active flow is located above La Laguna and continues to advance slowly. The unfavourable meteorological conditions for ash dispersion persist and are affecting the operation of La Palma airport and some airspace in between La Palma, La Gomera and Tenerife.

17 Oct La Palma eruption update 16th october 2021: Advance of lava flows slows

Although the effusive phase of the eruption continues to be more powerful currently than the more explosive strombolian phase, the active lava flow fronts are currently barely advancing. This is because of the existence of lava tubes, although the flows continue to widen and grow in height. Ashfall has been concentrated on the eastern side of the island to include the airport, and consequently airport operations have been affected and are expected to continue to be affected by the ash in the coming days. The lava flows currently cover 724 hectares, and at its widest the flow field is now 2,350 m wide. Regarding the 5 cm inflation seen at the Jedey LP03 station on the 14th October, that signal has now completely reversed, and the rest of the stations do not show significant deformation.

15 Oct La Palma eruption update 15th october 2021: Advance of lava flows speeds up

The eruption continues to show a mixed strombolian mechanism, with both explosive and effusive phases, although currently the effusive phase is the more predominant one. This has been observed downstream as an increase in fluidity of the active lava flows as a result of the greater supply rate of magma. During the night, the stream furthest north advanced at up to 250 m per hour, although it has slowed down to 20-30 m per hour. The area affected by lava is now 696 hectares, with the maximum width of the flow field 1,770 m. Regarding the inflation of 5 cm has been seen at the LP03 station between Jedey and Las Manchas yesterday, today it has shown a partial reversal, and no significant signals are seen in any of the other stations. During the afternoon, an old vent 300 m SE of the main cone reactivated although only with ash emission, and its activity decreased overnight.

14 Oct La Palma eruption update 14th october 2021: 400 more people in La Laguna evacuated

New evacuations, on the night of the 13th and then on the morning of the 14th, have been ordered in La Laguna given the advance of the active lava flows to the north of the flow field. These have affected about 400 extra people, increasing the total number of evacuees from the eruption to around 6,400. The two branches of the northern-most lava flow are still active, with the wider southerly branch slowing down, but the more northern branch continues to advance towards La Laguna. Large blocks are observed being transported in the northern lava flow, which are remnants of small collapses of the cone. The eruption continues to show a strombolian mechanism with both explosive and effusive phases, producing pyroclastic deposits and lava flows.