Eruptions Newsletter #9 for May 9, 2025

This week’s newsletter is a little shorter than normal because I’m knee deep in Finals Week!

Activity News

Likely the biggest activity news for this week was the announcement of the first time scientists witnessed an eruption on the planet’s mid-ocean ridges. That seems crazy at first — the mid-ocean ridge system is over 60,000 kilometers of volcanism that drives the spreading of ocean basins. However, as their name implies, they’re in the middle of oceans under thousands of feet of seawater. Being in the right place at the right time at the right depth to see some segment of the mid-ocean ridge (MOR) system erupt is, well, challenging to say the least.

This means that luck was going to play a big role in catching a MOR in action*. Luck happened. On May 3, an ALVIN dive in the Pacific Ocean off the coast of Costa Rica finally caught an eruption in action. From a week earlier, a seafloor ecosystem was wiped out by lava flows from the East Pacific Rise (EPR). The lava was still glowing orange when ALVIN reached the EPR, meaning the eruption had to have just happened as the group from Woods Hole arrived. All of this was happening almost 8,500 feet (2.5 kilometers) down.

To me, the fun part is they did not expect to see this when they headed down on that May 3 dive. In fact, the eruption started earlier in the day but scientists on the R/V Atlantis didn’t identify the noises on the ship’s hydrophones as an eruption until after ALVIN left. The MOR was likely erupting as they slowly drifted to the seafloor that day! In fact, the temperature of the seawater at the ocean floor was getting warm enough that the ALVIN pilot decided to end the dive and return to the surface.

What capturing the before and after of this eruption really does is help us understand how dramatically ecosystems can change at the seafloor. Natural hazards like lava flows can wreak havoc as quickly under the sea as well as on land. It will be fascinating to see how quickly the area recovers after this EPR eruption.

Odds & Ends

On a bit of a grizzly or somber note, archaeologists in what was once Pompeii discovered a group’s last stand against the 79 CE eruption. Remains of four people were found behind a bed frame that was stacked up against the door, likely trying to keep the volcanic ash and debris out of this building. Of course, this was a futile attempt to save themselves, but it does again humanize the terror of being trapped in a devastating volcanic eruption like Vesuvius can unleash. You can see some of the remarkable artifacts and archaeology of Pompeii and the area in this new report (note: it is in Italian).

In other Vesuvian news, researchers have started transcribing scrolls burned in the eruption using x-ray technology and AI. The scrolls examined so far seem to be a library of Greek philosophy, likely lost until now. This is a use of AI I can get behind.

Sounds of the Week

That’s it for this week while I dig out from the semester (and academic year). I will leave you with a new Aesop Rock song because … well, it’s a new Aesop Rock song.

Questions? Comments? Thoughts? Feel free to send me a note or follow me on Bluesky (@erikklemetti.bsky.social).