Tonga Geological Services reported that eruptive activity at Home Reef continued as of 24 December. Satellite data processed by the MIROVA monitoring system showed ongoing thermal anomalies. Sentinel-2 images indicated that the NE part of the island grew by at least 1,000 square meters between 7 and 12 December. The new lava had covered approximately 75,000 square meters by 15 December, including the previously existing island and the new NE area. Satellite imagery on 15 December showed white and gray emissions above the volcano. The Maritime Alert Level remained at Orange (the third level on a four-level scale), and mariners were advised to stay at least 4 km away from the island. The Aviation Color Code was raised to Yellow (the second level on a four-level scale), and the Alert Level for residents of Vava’u and Ha’apai remained at Green (the first level on a four-level scale).

Geological Summary. Home Reef, a submarine volcano midway between Metis Shoal and Late Island in the central Tonga islands, was first reported active in the mid-19th century, when an ephemeral island formed. An eruption in 1984 produced a 12-km-high eruption plume, large amounts of floating pumice, and an ephemeral 500 x 1,500 m island, with cliffs 30-50 m high that enclosed a water-filled crater. In 2006 an island-forming eruption produced widespread dacitic pumice rafts that drifted as far as Australia. Another island was built during a September-October 2022 eruption.

Sources: Matangi Tonga Online, Tonga Geological Services, Government of Tonga