Nov. 11, 2011 -- Just off the coast of the Spanish Canary Island of El Hierro, a new volcanic island is close to breaking the surface. After months of seismic activity and underwater eruptions that have caused repeated evacuations of the port city of La Restinga, a still unnamed volcanic cone is emerging from the seafloor.
The milky green and brown plume shown in this photo is likely a mix of volcanic gases and a blend of crushed pumice and seafloor rock.
For the second time in the last 30 days toxic fumes from the eruption forced the evacuation of 600 residents from port city of La Restinga on Nov. 5. The city remains at Red Alert, though the levels of carbon dioxide and hydrogen sulfide have since subsided. In the past week, 32 earthquakes related to the eruption have been strong enough for residents to feel; 80 residents were evacuated specifically due to landslide risk from the shaking.
"Spanish volcanologists are saying that some residents of the evacuated village are annoyed because they don’t feel in danger," wrote Spanish mainland resident Jorge Esteves in an e-mail to Discovery News. "But you know, eruptions are unforeseeable, and there is a Spanish proverb that says 'Más vale prevenir que curar'—It’s better to prevent that to cure."
Officials ordered ships and aircraft away from the island’s southern tip on Saturday amid reports that chunks of volcanic rock coughed up in the eruption had become airborne, according to the Associated Press. This chunk of erupted material collected offshore was displayed at the town of El Pinar, Hierro Island, Spain, on Oct. 21, 2011.
The Instituto Geográfico Nacional reports that more than more than 11,000 tremors and earthquakes have been recorded near El Hierro since July 17. The underwater volcanic eruption began on Oct. 10 and was the first eruption in 40 years for the Canary Island chain of volcanoes. The last eruption was the Teneguía volcano in 1971 on the island of La Palma.
El Hierro is a volcanic island sitting above a tectonic hot spot in the Atlantic Ocean off of North Africa and Spain. The new volcanic cone erupting, since mid-October, is growing out of the sloping, underwater flank of the main island. The Advanced Land Imager (ALI) on NASA’s Earth Observing-1 (EO-1) satellite acquired this natural-color image a milky green plume of volcanic material in the waters surrounding El Hierro's southern tip on Nov. 2.
This topographic view of the seafloor show the new volcanic cone and lava plume that has emerged in a canyon off the coast of El Hierro.
Helicopters from the Canary Civil Guard are monitoring the eruption at the surface where a jacuzzi of boiling water can be seen.
This image shows the jacuzzi of warm water broiling over the underwater eruption. The following slide shows the thermal imaging of this same shot.
The ultimate danger to island inhabitants is still unclear. For now scientists’ best guess is that the eruption is happening 50 to 100 meters below the sea surface, and it is warming the waters by as much as 10 degrees Celsius, according to geologist and blogger Erik Klimetti.
Waters south of the island have been bubbling and fizzing for weeks, forming a submerged plume that stretches for tens of kilometers. In the past week, though, small explosions have breached ocean surface. This photo shows steaming bits of rock ejecting out of water.
But the spewed material is building toward the ocean surface with each passing day. If the eruption completes its transformation from submarine to Surtseyan, explosive columns of steam and ash will become the mainstay—and a new bit of island will be born. This image shows the jacuzzi of warm water churning off the coast as of Nov. 7.