THE GUARDIAN



 

 
Crescent-shaped landmass 50km south of Minami Ioto could disappear due to erosion

The 6,000-plus islands that make up the Japanese archipelago have a new addition, after scientists said an undersea volcanic eruption 1,200km (745 miles) south of Tokyo had created a new landmass.

The island was formed in the Pacific Ocean about 50km south of Minami Ioto, the southernmost island of the Ogasawara group.

Japan’s coastguard said the new island is crescent-shaped with a diameter of about 1km.

But if history is any precedent its presence could prove ephemeral.
Much will depend on what it is formed from: ash and other fragments are unlikely to resist a constant battering from waves, but continued volcanic activity could produce lava flows that eventually form a more durable hard shell.

Islands formed in a similar way in the area in 1904, 1914 and 1986 all disappeared due to erosion.

In 2013, weeks of volcanic activity gave rise to an island that merged with an existing island, Nishinoshima, to create a new landmass that, for a while, bore a resemblance to the cartoon dog Snoopy.

 

Japan’s meteorological agency believes the latest eruption, which began late last week, could continue and has issued warnings about smoke and large ash deposits in nearby waters, according to the Mainichi Shimbun newspaper.

The coastguard discovered the island on Sunday after observing the eruption from the air, the newspaper said, adding that crew had also found pumice (volcanic rock) deposits floating on the sea across a wide area.

The appearance of new islands in Japan’s southernmost reaches can have potential geopolitical ramifications if their location enables the government to expand the country’s territory, if only by a few hundred metres.

However, even if the newest landmass survives and is added to Japan’s territory, its location near Minami Ioto means it is unlikely to require changes to the country’s territorial waters or exclusive economic zone, the Mainichi said.