The more intense activity in the strombolian vents in the main cone that began on the 17^th continues to be seen in the form of larger pyroclasts being emitted. From 8pm local time, an overflow of the lava channel by the cone was observed and was accompanied by an increase in lava emission rate. Regarding lava flows, the most active is flow number 4, which is 300 m from the sea between La Laguna and Todoque mountain. Flows 1, 2 and 9 feeding the lava delta are also active, and the total area affected by the lava flows is now 1,040 hectares. After the peak in earthquake frequency and magnitude on the 17^th, the rate of seismicity dropped today. 92 events were recorded, with similar amounts at both intermediate (10-15 km) and deep (30-45 km) depths, with the day’s largest earthquake being a mbLg 4.4 event at 34 km depth.

SO2 emissions remained high and similar to the 17^th at 17,000-26,000 tons per day, whilst the ash and gas plume was at 3,500 m. However, satellite measurements imply current SO2 emissions are lower than the start of the eruption. After a couple of days of increasing, the volcanic tremor decreased back to low levels, whilst deformation continued as seen since the start of November, with variable deformation at the LP03 GPS station in Jedey closest to the eruption and a small weakening regional deflation signal in the other stations. Air quality improved relative to the last two days, with SO2 levels reaching good or reasonably good in all stations on the island, except Tazacorte which exceeded the alert threshold (500 μg/m³) once in the late evening. PM10 levels improved in Los Llanos from unfavourable to reasonably good levels throughout the day, and in the rest of the stations PM10 levels remained between good and reasonably good.

An image taken looking south from La Laguna mountain showing the progress of one of the active lava flows north of Todoque mountain, which is flowing over older flows causing them to thicken. Image credit: 112 Canarias, Government of the Canary Islands

Sources: Government of the Canary Islands, PEVOLCA, Involcan, IGN, DSN, Cabildo La Palma, 112 Canarias, Tolouse VAAC, Copernicus EMS