GREENVILLE, N.C. (WNCT) — Japan is home to 10% of the world’s active volcanoes. But most of the volcanoes aren’t visible from the surface of Earth.
Japan’s Fukutoku-Okanoba volcano is an underwater volcano, just three miles north of South Iwo Jima. The Japanese Coast Guard has reported patches of milky blue water popping up in that area over the past decade.
But on August 13, there was much more to see than discolored water.
A towering plume of steam and volcanic gases rose above the water, a sure sign that eruptions were happening beneath. By August 14, the smoke from this underwater volcano reached as high as 11 miles above the surface.
This caused an issue for aviation. Volcanic ash is made up of jagged rock particles that can damage and even cause plane engines to fail. The Japan Meteorological Agency issued an ash advisory, with multiple flights canceled as a result.
It also created a boating hazard. On August 17, satellite imagery captured a newly formed Island of pumice drifting near the eruption site. It’s over 60 miles long. Pumice is one of the only types of rock that can float, for months or even years at a time, due to a combination of surface tension and air-filled holes within it. These rocks can scrape a ship’s hulls and propellers as well as clog cooling systems and engines.
Even though more than 80% of volcanoes are underwater, scientists are still developing marine warning systems to give people the best possible chance to respond in time.