Fukutoku-Okanoba is a submarine volcano, but its summit is just 14 meters (46 feet) below sea level. When the volcano erupted in early February 2010, Japan’s coast guard captured the event on video. The volcano released ash and steam plumes, and evidence of the volcano’s activity lingered days later when the Advanced Land Imager (ALI) on NASA’s Earth Observing-1 (EO-1) satellite captured this true-color image on February 11, 2010.
The clearest evidence of activity at Fukutoku-Okanoba is the discolored water west of the summit. Vapor released by Fukutoku-Okanoba might account for the clouds floating overhead, but they might be unrelated to the volcano.
Roughly 5 kilometers (3 miles) northeast of the island of Minami-Iwo-jima and about 1,000 kilometers (600 miles) south of the main Japanese archipelago, Fukutoku-Okanoba occurs in an area where several short-lived volcanoes formed in the twentieth century.
NASA Earth Observatory image created by Jesse Allen, using EO-1 ALI data provided courtesy of the NASA EO-1 team. Caption by Michon Scott.
Acquired February 11, 2010, this true-color image shows water discoloration immediately west of the underwater summit of Fukutoku-Okanoba. Clouds overhead might result from vapor emissions, but might be unrelated to volcanic activity.
Acquired February 9, 2010, this image shows ocean water discolored by the submarine eruption of Fukutoku-Okanoba. The water affected by ash appears electric blue, in contrast to the surrounding navy blue water.