Evaluating last year’s eruption in the Canary Islands

One of many most damaging volcanic eruptions of 2021 was the occasion in The Palm within the Canary Islands. the eruption lasted for months and completed bury an necessary half of the communities that had been constructed on its slopes. Thankfully, it was an eruption that didn’t find yourself claiming lives, however the harm was estimated to be at the least $1 billion. It seems that the eruption itself, in comparison with others, was comparatively small, however the human influence was a lot higher.

A new examine in Nature by Riccardo Civico and others has offered us with high-resolution digital elevation fashions (DEMs) of the La Palma eruption. These fashions had been created from over 12,000 photos to create a map that has a decision of 0.2 millimeters per pixel (beneath). That is 0.007 inches per pixel, or in regards to the measurement of two sheets of paper stacked edge to edge. Now that is excessive decision! This knowledge signifies that we will actually assess what occurred. It seems that the lava flows and volcanic particles from the brand new cone that fashioned on the volcano had been greater than spectacular.

Excessive-resolution DEM of the 2021 La Palma eruption. Credit score: Civico et al. (2022) in Nature/INVOLCAN.

Placing a scale within the lava

Over the course of 85 days, the world within the Cumbre Vieja rift on La Palma noticed greater than 7 billion cubic ft (0.2 cubic kilometers) of lava and particles pour out. Though that feels like loads, it’s 1/7 the dimensions of the 2018kYolaue rash and 1/5 the dimensions of the 2014-15 Holuhraun eruption in Iceland. A historic eruption that was fairly near the identical scale as La Palma was the well-known 1943-52 Eruption of ParicutΓ­n in Mexico. All of those eruptions make good comparisons as a result of they erupted very comparable forms of lava in comparable kinds.

The volcanic cone that fashioned throughout the eruption (see above) totaled 1.3 billion cubic ft. To place that into some perspective, that is roughly equal to fifteen Nice Pyramids of Giza. Not dangerous for 3 months of volcanic exercise. All of this was taking place at an eruption charge of between ~700-1700 cubic ft per second (20-50 cubic meters per second). that is one thing round 66-166 tons (60,000-150,000 kilograms) of lava and particles pouring out of the vents each second!

These sorts of numbers are tough to place into any context that we’re accustomed to in our on a regular basis lives. Nonetheless, by way of volcanic eruptions, they actually aren’t that out of the atypical. Volcanic exercise is that vigorous on our planet! Even what is taken into account a reasonably small to reasonable sized rash, rated 3 on the Volcanic Explosivity Index — appears wonderful.

very liquid lava

Lava movement map for the 2021 La Palma eruption, utilizing elevation change as an indicator of latest lava movement deposits. Credit score: Civico and others (2022) in Nature.

seems the chemical properties of magma it additionally helped them movement up to now and so shortly. The lava itself was wealthy in alkaline parts comparable to sodium and potassium, a lava known as Basanite. Such a lava is just like basalt (the stuff that erupts in Hawaii) however is way much less viscous (sticky), so it may movement quicker and farther than its Hawaiian counterpart.

Presently, Cumbre Viejo on La Palma is comparatively quiet because the eruption was declared accomplished December 2021. There have been occasional earthquake swarms and the the bottom beneath elements of the brand new cone remains to be glowing with the warmth of the lava cooling. Maybe La Palma will sleep once more for 50 years because it did after the 1971 eruption. Maybe it’s going to erupt once more this 12 months. We do not know (and anybody who says in any other case is promoting one thing). Volcanologists will proceed to watch the volcano for indicators of doable unrest on this volcanic island within the Atlantic.

Leave a Comment