Alert level: Orange
It has been rising through a crack about two kilometres down since Tuesday evening and it has not slowed. Orange means an eruption is considered likely in days to weeks, not that one is under way.
The ring road north of the pass is closed. The hiking routes are closed. No evacuation has been ordered and none is being prepared.
Level raised 04:00, Tuesday 12 August · page last written 06:40 today
Measured against the fourteen-day median for this system. Values in red are outside the range recorded since monitoring was upgraded in 2019.
| Measure | Now | 14-day median | Note |
|---|---|---|---|
| Located events, 24h | 1,842 | 228 | Shallowing. Median depth down from 5.1km to 2.2km since Tuesday. |
| Sulphur dioxide | 9,400 t/d | 780 t/d | Airborne traverse at 09:20. Plume tracking south-west. |
| Ground uplift | 31 mm | 0 mm | Cumulative since 04:00 Tuesday, GNSS station KLB2. |
| Volcanic tremor | Continuous | Absent | Onset 19:40 yesterday. Amplitude steady, not rising. |
| Crater lake temperature | 31 °C | 29 °C | Within normal variation for August. |
Located events above magnitude 2.0 in the past thirty-six hours. Depths are below sea level. The fissure floor is at 640 metres.
| Time | Mag | Depth | Location and notes |
|---|---|---|---|
| Today 03:51:22 | M4.1 | 2.1 km | 400m north of the 2021 crater. Felt in Hvalstaðir, no damage reported. |
| Today 03:12:08 | M3.3 | 1.8 km | One of ninety-six events located in eleven minutes. |
| Today 01:44:57 | M2.9 | 3.4 km | Sequence migrating south-east at roughly 200m per hour. |
| Yesterday 23:19:41 | M4.6 | 1.4 km | Largest so far. Rockfall on the eastern rim, observed from the air. |
| Yesterday 19:40:12 | — | — | Onset of continuous volcanic tremor. Has not stopped since. |
| Yesterday 16:02:33 | M3.0 | 4.9 km | First event of the current sequence. |
An eruption at Kaldbrún would most likely open as a fissure along the existing line rather than as a single crater. Modelled lava paths reach the ring road in nine to fourteen hours and do not reach any occupied building.
The realistic hazards for people nearby are gas, not lava. Sulphur dioxide at the concentrations measured this morning is dangerous to anyone with asthma or a heart condition, and the plume is going south-west, over Hvalstaðir.
If the situation changes you will hear it from the civil protection service, by phone alert and by siren. You will not hear it here first. This page is a record, not a warning system.
The intrusion stalls without reaching the surface. Seismicity decays over one to three weeks, uplift reverses, and the alert level returns to Yellow. This is what happened in 2017 and again in 2021.
A fissure eruption on the existing line, opening with between twenty minutes and two hours of warning. Lava confined to the valley. Ash minor, gas significant.
An eruption under the ice cap to the north-east, producing meltwater flooding down the Kaldá within hours. The bridge is closed automatically if this begins.
Continuous waveform, GNSS baselines, gas flux and thermal are open. No key, no rate limit, no attribution required. If it is useful to you, cite the observatory so we can keep funding the instruments.
| Waveform | miniSEED, 100 Hz, twelve stations, rolling 90 days |
|---|---|
| GNSS | Daily and 5-minute solutions, RINEX, since 2009 |
| Gas | DOAS traverses and scanning results, since 2014 |
| Archive | Everything before 2009 is on paper. Write and we will scan it. |