Japan's Nishinoshima volcano island is located about 600 miles south of Tokyo, Japan. After 40 years of dormancy, it erupted in November 2013 leaving lava flows that were active until 2015. Then it erupted again in mid-2017 which contributed to the island's continued growth.
There was also a short eruption in July 2018 producing a new lava flow and vent on the side of the pyroclastic cone. Then in December 2019, it erupted again, which continued until February 2020, according to the Japan Meteorological Agency (JMA).
The Japan Coast Guard has observed multiple eruptions since late May, and by June, ash could be seen as high as 27,200 feet which contributed to its expansion. Experts have noted that the island has had an additional 500 feet from June 19 through July 3.
Indeed, Nishinonshima had grown 12 times than its original size since 2015 when it merged with a smaller island that was created by an underwater volcano.
Nishinoshima: A volcanic island merges with a smaller island
Nishinoshima first emerged from the sea in the 1970s. It is located 600 miles south of Tokyo, Japan and had its first eruption in 2013 after 40 years of being inactive.
However, in 2015, underwater in the Pacific Ocean emitted ash and magma to the surface and high up in the air. This dramatic build-up formed a new island located just off the coast of Tonga, in a region known as the Ring of Fire.
The small island was named Hunga Tonga, measuring about 0.6 miles wide and was mostly composed of ash from the volcanic explosion.
Many experts thought that Hunga Tonga would deteriorate into the water because of its weak structure. But they did not expect that the small islet would merge with Nishinoshima, which results in a larger island growing 12 times its original size since it was discovered.
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Nishinoshima is experiencing a 'vigorous growth spurt'
According to a report by MailOnline, Nishinoshima seems to be more awake because it has had numerous eruptions over the past few months, which added land to its surface. The Japan Coast has reported that a powerful explosion happened on July 1 which created a dense dark ash plume that rose approximately 11,482 feet into the air.
The US National Aeronautics Space Administration (NASA) released a satellite image of the volcano's eruption on July 4. It showed the lava flowing from the volcano and the cooling of dark plume ash blowing to the north.
According to the Japanese officials, the volcanic activity began around late May and then showed volcanic plume as high as 15,400 feet on July 3. By the next day, July 4, the ash was already at 27,200 feet, the highest plume so far since 2013.
Nogami Kenji, a professor at the Tokyo Institute of Technology, told NHK news agency of Japan that Nishinoshima appears to be at the most active right now and is being powered by the massive supplies of magma beneath it.
NHK news agency reports that researchers from the Geospatial Information Authority of Japan said that the southern part of Nishinoshima has expanded by almost 500 feet inland since June 19 to July 3.
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