Forecast 8:40 am Sunday tsunami wave activity for Tonga [1]
Sunday, February 28, 2010 - 06:35. Updated on Sunday, May 25, 2014 - 22:04.
A tsunami wave moving across the Pacific this morning following an 8.8 earthquake in southern Chile is expected to reach Tonga's coastlines at 8:40 am Sunday 28 February but it is not known how high the wave will be. A tsunami warning is in effect for the whole of Tonga and the Pacific Islands.
The wave is approaching Tonga from the south-east and the Pacific Tsunami Warning Centre estimates the initial wave arrival time at 8:40 am local time.
According to their bulletin # 013 wave activity measured 1.79M / 5.9FT at Hiva Oa Marquesas; and 0.95M / 3.1FT at Nuku Hiva Marquesas; with Papeete Tahiti recording 0.16M / 0.5FT.
The first Tonga reading was "DART TONGA 51426 23.0S 168.1W 1844UTC 0.04M / 0.1FT.
Tonga's Met office said this forecast arrival is less than two hours after the high tide at 6:50 am this morning. The wind is currently blowing at 15-20 knots from an east-south-east direction.
According to the Pacific Tsunami Warning Centre the wave activity had the highest measurement of 2.34m (7.7ft) at the town of Talcahuano in Chile last night, and was smaller as it spread out across the Pacific.
In the eastern Pacific, the Galapagos Islands recorded 0.35m (1.2 ft); Easter Island 0.35m (1.1ft); and the island of Rikitea 0.18m (0.5ft).
The Chilean earthquake was centred at 36.1S latitude and Tonga is on 21.0S latitude so the wave is approaching Tonga from the south east.
Tonga trench
Tonga's chief geologist Kelepi Mafi told Matangi Tonga this morning that the 10 km deep Tonga Trench will give Tonga some protection from tsunamis approaching from the east.
"The Tonga Trench helps to lessen the wave. It is a form of protection because it needs a lot of energy to push the water through it," he said.
He said all the islands in Tonga are on the Australian plate on the western side of the trench, which holds some of the deepest waters in the world.
But Kelepi warned that a tsunami wave could affect all coastlines in Tonga and not just those facing the east or south east.
A tsunami warning remains in force for the whole of Tonga.
The Tonga warning advises that All persons in coastal and low lying areas all over Tonga are advised to pay special attention to A3Z radio/TV for directions and instructions. It is essential to take precautions now and wait for further notice while the tsunami warning centres are investigating the event to determine the level of danger.