Photo/Illutration A new island that was formed by eruptions of the Fukutoku-Okanoba undersea volcano in the Ogasawara island chain, front, is being eroded by waves in October 2021. The Minami-Iwojima Island is seen in the background. (Kotaro Ebara)

An eruption of a submarine volcano called Funka Asane in the Ogasawara island chain was detected on March 27, prompting a warning for ash and rocks as well as floating pumice to be issued. 

According to the Japan Meteorological Agency, smoke billowed from the volcano and reached a height of around 7,000 meters. The agency has issued a warning of falling ash in the Ogasawara chain south of Tokyo. However, there is no report of it in the area so far.

Funka Asane is located around 160 kilometers southwest of Hahajima island of the Ogasawara islands. At around 6 p.m. on March 27, the Himawari weather satellite detected smoke billowing from Funka Asane.

Then, just after 11 p.m. that day, the JMA issued a warning for a volcanic eruption in the nearby area of the sea. The agency is urging caution against rocks or smoke erupting from the volcano, as well as floating pumice on the surface of the sea.

According to the agency’s records, volcanic eruptions from Funka Asane were detected from fishing boats from 1930 to 1945. After this period, discoloration of the seawater in nearby areas has been reported many times.

In August, another underwater volcano called Fukutoku-Okanoba, located around 130 kilometers south of Funka Asane, erupted, resulting in smoke billowing up to around 16,000 meters.

The eruption wreaked havoc on Okinawa Prefecture and other places by spewing out huge amounts of pumice, which reached coastal areas there.