Home reef aviation alert downgraded to yellow [1]
Wednesday, September 28, 2022 - 06:09
A new island has continued to form in Tonga's western volcanic chain, during 17 days of the Home Reef effusive lava flow eruption, continuing since Saturday 10 September.
The island as of Monday 19 September 2022, measured 211m North-South and 218m East-West with an approximate total surface area of 8.6 acres and an estimated height of 15 metres above sea level. There are no hazard alerts for residents in Vava’u and Ha’apai.
Tonga's Geological Services who are issuing daily updates on the eruption, reported that the Aviation Alert level was lowered from Orange to Yellow on 27 September.
The TDS update on Home Reef Volcano No.16 (27 September) stated that the volcanic activities in the previous 24 hours was progressive with 21 volcanic events, one of which was ash eruption compared to 15 volcanic events in the prior 24 hours. There were a total of 36 volcanic events, one of which was volcanic ash event detected at 12:36am. This corresponded with the volcanic ash event captured in the satellite imagery at 12:30AM at a height up to 6-8km above sea level within 25km SSE of the vent.
TGS said the volcano activity poses low risk to the Vava’u and Ha’apai communities.
Home Reef is located 25 km southwest of Late Island, 22 km northeast of Lateiki (Metis Shoal) and 75 km northwest of Mo’unga’one Island at Latitude & Longitude 18.992°S & 174.775°W.
Monitoring of the eruption is ongoing with daily notices issued on the status of the eruption.
Hazard Map
TGS has issued a Hazard Map (No Go Zones) to guide all Mariners sailing near Home Reef. Continuous monitoring is carried out daily with advisories for the public.
The Volcanic Hazards Map for Home Reef eruption has three zones:
Zone 1 - Highest Risk (No Access Permitted)
Zone 2 - Moderate Risk (Restricted Access Only)
Zone 3 - Low Risk
The hazards in Zone 1 include the risk of explosions, ballistic ejecta, tephra, lava domes, laze, vog, pumice, islands/shoals, and volcanic edifice collapse.
In Zones 2 and 3 there is a risk of vog, laze, pumice, submarine plumes, tephra and tsunamis.