The Copernicus-2A satellite imaged the smoke plume and lava flow from the eruption of the Fagradalsfjall volcano near Grindavík, Iceland yesterday; Marco Langbroek processed natural-colour and short-wave infrared imagery to achieve the above image, which he posted to Bluesky. [Kottke]

Previously: Earthquake Swarms and an Imminent Eruption in Iceland.

A swarm of thousands of earthquakes have been recorded on Iceland’s Reykjanes Peninsula over the past three weeks. It’s a strong indication that a volcanic eruption is imminent. The town of Grindavík has been evacuated as a result. The Icelandic Meteorological Office has a page with updates and maps of earthquakes and ground deformation from the magmatic intrusion (examples above). A post on Earthquake Insights has more maps, plus geological and historical context.

Scientists have now mapped the seafloor around the Hunga Tonga-Hunga Ha‘apai volcano, and as a result we have learned just how massive the January 2022 eruption was. By comparing their soundings with 2017 data, they determined that at least 9.5 km³ of material was discharged. Debris was found 80 km from the volcano, and the volcano’s caldera has been replaced by a cavern 850 m deep. More from the NIWA media release and from ABC (Australia).

Previously: Remotely Operated Vessel Maps Tonga Caldera.

As part of the Tonga Eruption Seabed Mapping Project, a robotic vessel has conducted a bathymetric survey of the Hunga Tonga-Hunga Ha‘apai volcano’s underwater caldera. Said volcano, you will recall, erupted spectacularly last January. The 12-metre vessel, USV Maxlimer, was controlled remotely from 16,000 km away, and carried sensors to measure the state of the seabed, temperature, salinity, turbidity, dissolved oxygen and chemical plumes. More at the press release. BBC News coverage.

Previously: The Rise and Fall of Hunga Tonga-Hunga Ha‘apai; Hunga Tonga-Hunga Ha‘apai, Before and After; How Satellites Revealed the Hunga-Tonga Hunga-Ha‘apai Eruption.

Every two years or so, NOAA’s National Centers for Environmental Information updates poster maps based on its Global Historical Tsunami, Significant Earthquake and Significant Volcanic Eruption databases; the 2022 editions are now available. The posters, made in collaboration with the International Tsunami Information Center, are distributed to emergency response personnel; they provide a historical overview of where earthquakes or eruptions took place, or tsunami originated, going back literally millenia. The maps can be downloaded in PDF format: Significant Earthquakes 2150 B.C. to A.D. 2022, Tsunami Sources 1610 B.C. to A.D. 2022, and Significant Volcanic Eruptions 4360 B.C. to A.D. 2022.

Previously: Hunga Tonga-Hunga Ha‘apai, Before and After.

NASA Earth Observatory has released digital elevation maps of Hunga Tonga-Hunga Ha‘apai both before and after the volcanic eruption earlier this month.

The digital elevation maps above and below show the dramatic changes at Hunga Tonga-Hunga Ha‘apai, the uppermost part of a large underwater volcano. It rises 1.8 kilometers (1.1 miles) from the seafloor, stretches 20 kilometers (12 miles) across, and is topped by a submarine caldera 5 kilometers in diameter. The island is part of the rim of the Hunga Caldera and was the only part of the edifice that stood above water.

Now all of the new land is gone, along with large chunks of the two older islands.

The Washington Post’s coverage is typically first rate, its maps providing both detailed coverage and context: start there. More detailed maps come from the Kīlauea section of the USGS’s Volcano Hazards Program website, with fissure maps of the entire eastern rift zone (see above) and thermal maps of the Leilani Estates fissures receiving daily or near-daily updates.

The eruption was preceded and accompanied by a number of earthquakes; NOAA has created an animated map showing the incidence, magnitude and depth of the earthquakes that took place during the week of the eruption.

The Smithonian’s Earthquakes, Eruptions and Emissions interactive map “is a time-lapse animation of volcanic eruptions and earthquakes since 1960. It also shows volcanic gas emissions (sulfur dioxide, SO₂) since 1978 — the first year satellites were available to provide global monitoring of SO₂.” [Axis Maps]