A. Situation analysis
Description of the disaster
On 20 December 2021, an eruption was observed at Hunga Tonga and Hunga Ha'apai, two sister volcanic islands with an underwater volcano linking them underwater. The volcano is located in an uninhabited area, some 65 km north of Nuku'alofa, Tonga's capital. A 16km high ash cloud formed. Advice was given to people in Tonga to protect water tanks from possible acidic rainfall in both Tonga and Fiji. The volcano was declared dormant on 11 January 2022.
The volcanic activity restarted on 14 January 2022, with volcanic ash, steam and gas erupting 5-20km above sea level. This led to a generation of small tsunami waves of 30cm. A tsunami alert was initiated by Tonga Meteorological Services and then later lifted on the same day.
A major eruption occurred at 17:20 on Saturday 15 January 2022, lasting about eight minutes, rattling windows and sending ash 15km into the air in a 5km plume. The eruption and vibrations were felt in Fiji, 800km away. The Tonga Meteorological Services re-instituted a tsunami alert for all of Tonga in the early evening of Saturday, 15 January.
Tsunami alerts were issued for Fiji, Samoa, and other neighbouring areas. In Tonga, tidal waves were seen to inundate coastal roads and properties at 2.7 feet (0.82m). Significant thunderstorms and lightning were experienced in the evening, and ash cover was reported to be 1-2cm as of 16 January morning. The ash cloud has grown over 12 hours but appears to be dispersing slightly, and the ashfall has currently stopped.
No injuries or deaths are reported as of 16 January 2022, but it has been reported that Tongatapu and 'Eua have been badly affected especially the east coasts. Communication with Tonga has been down since 18:30 on Saturday 15 January. It is presumed that the undersea internet cable to Tonga from Fiji has been damaged, although the responsible cable network has not been reachable for comment. The fibre optic cable was previously severed in 2016 and took two weeks to restore. Satellite phones are currently not working reliably. The Digicel network is on and off again, dependant on the power supply, which is currently unstable. This has made it difficult to gather and receive information on the current situation. A state of emergency was called on 19 January.
Waves were reported to have inundated islands in the Lau group of Fiji – Ketei and Vatoa – two of Fiji's outer islands to the southeast. Families were evacuated, and no damage was reported. Higher waves were experienced in Port Vila, Vanuatu, but no damage was reported, and an all-clear from Vanuatu Meteorological Services was issued. In Samoa, 200 households were evacuated, but the tsunami watch for Samoa was subsequently cancelled. No damage has been reported in Fiji by the end of 16 January, but a tsunami advisory remains due to the ongoing eruptions. There remains the possibility of further undersea eruptions and/or further tsunami waves or ashfall.
The tsunami was also noticed in Japan, where between 20cm-1.20m waves were observed in many parts of coastal areas facing the Pacific Ocean from the night 15-16 January until morning. Many residents of the area evacuated to safer places during the night. Railway and ferry services in some areas were suspended. No major damages were reported by 16 January in Japan, but damages are not yet confirmed. Reportedly, fishing boats at some ports capsized or sunk from the waves. There were reports of the tsunami waves also occurring elsewhere in the Pacific, for instance, in Hawaii, Peru and Chile.
To date, there has been only one confirmed case of COVID-19 in Tonga in October 2021. Tonga has strict border controls in place, and there is a risk that it could impact the timely importation of relief items.