Today marks one month since the beginning of the eruption that is ongoing at the Sundhnúkur crater row. The eruption, which began on the evening of March 16, is the fourth in a series of eruptions that started when magma began accumulating beneath Svartsengi in late October 2023.

Yesterday (25 March) a seismic swarm occurred in the NW part of the Askja caldera. About 30 earthquakes were detected between 08.00UTC and midday. The largest earthquake detected had a magnitude M3,5 at a depth of about 5 km. Three earthquakes with magnitudes between M2 and M2,5 were also detected, the rest of the activity was characterized by smaller events. Overall, the seismic activity in the Askja has been quite stable between months and unchanged until yesterday. Looking back, we can see that earthquakes with magnitude above M3 were detected in January 2022 and October 2021.

The weather in 2023 was mostly favorable. It was calm, dry, relatively little snow and stormy days were quite uncommon. However, the year was cooler compared to the most recent years. The average nationwide temperature was 0.1°C colder than the average temperature between 1991 and 2020, and 0.4°C colder than the average temperature of the last ten years. It was relatively coldest in the North, while the Southwest and Southern coast were relatively warmer. The weather was particularly cold in the beginning of the year and again in March. June, on the other hand was exceptionally warm in the North and East. It was the warmest June on record in many places in those regions. The year was relatively dry, with precipitation below average across most of the country. There were several dry periods during the year, such as in March and July, but there were also periods of heavy rain in between. May and June were particularly wet and gloomy in the southern and western regions.

On 10 November 2023 the town of Grindavík in Iceland was evacuated as massive amounts of magma suddenly flowed into a magma filled crack that propagated underneath the town. Magma was emplaced in a 'vertical sheet' type intrusion in the Earth's crust. An international team of scientists explains the formation of the intrusion, and conditions for ultra-rapid flow into cracks, in a new publication in the prestigious scientific journal Science.

Updated 23 January at 9:00 UTC

Since the glacial flood reached its peak in the river Gígjukvísl approximately a week ago, the water level has been decreasing and is now comparable to what it was before the flood. The seismic tremor measured on the seismometer at Grímsfjall has also declined, with seismic noise now back to normal levels. Since last week Monday, 21 earthquakes have been recorded in Grímsvötn, including two earthquakes exceeding magnitude two.