The new island appeared surfaced eleven hours after the eruption and continues to grow in size.
On September 14, researchers with Tonga Geological Services estimated the area of the island to be 4,000 square metres (1 acre) and elevated to 10 metres (33 feet) above sea level.
By September 20 the island had grown to 24,000 square metres (6 acres).
The new island is located southwest of Late Island, northeast of Hunga Tonga-Hunga Ha‘apai, and northwest of Mo‘unga‘one, all part of the kingdom of Tonga which is situated in the continent of Oceania and already contains more than 100 islands.
The seafloor ridge that stretches from New Zealand to Tonga has the highest density of underwater volcanoes in the world.
The erupted volcano has repeatedly oozed lava and ejected plumes of steam and ash, discolouring the surrounding water in the days since.
Previous research suggests that these plumes of superheated, acidic seawater contain particulate matter, volcanic rock fragments, and sulphur.
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While islands created by submarine volcanoes are often short-lived, they occasionally live for years.
Home Reef has had four recorded periods of eruptions, including in 1852 and 1857 when small islands temporarily formed.
An eruption in 2006 produced islands with cliffs that were 50 to 70 metres high.
“The volcano poses low risks to the aviation community and the residents of Vava‘u and Ha‘apai,” the Tonga Geological Service said in an update issued on September 20.
“All mariners are, however, advised to sail beyond 4 kilometres away from Home Reef until further notice.”
On September 23, Tonga Prime Minister Siaosi 'Ofakivahafolau Sovaleni delivered a stark message on the dangers posed by climate change in an address to the UN General Assembly.
He emphasised the unique vulnerabilities of island nations such as his.
"Threats from climate change, pandemics and conflicts have increased. This is not some temporary inconvenience. This is about our survival," he said.
"The adverse impact of climate change makes Tonga the third most vulnerable country in the world. This threatens our territorial integrity our land, water, health, infrastructure, food security, biological diversity, livelihoods and ecosystems. It threatens people's mental health, and our sense of nationhood."