The South Pacific island of Tonga's hongaha ApaI island erupted on the 14th and 15th, and a tsunami was observed in the capital Nukualofa. Japan, the United States, Canada, New Zealand, Fiji, Samoa, Vanuatu, Australia and Chile all issued tsunami warnings. Experts pointed out that the crater at the site of the incident has awakened, and the active period of eruption can last for weeks or even years. It is not clear whether it has reached the peak of eruption. Tonga volcanic eruption Hongaha ApaI Island, 65 kilometers north of nukoalofa, the capital of Tonga, began volcanic eruption on the morning of the 14th and erupted again on the afternoon of the 15th. The volcanic eruption caused a large amount of volcanic ash, gas and water vapor to enter the high altitude, forming a huge cloud, which erupted to 20 kilometers high altitude. The volcano started on December 20, 2021 and erupted continuously for several days. In 2015, hongaha ApaI island volcano also erupted. After the eruption of the volcano on the 14th, Tonga government departments were closed, and Tonga national Tsunami Warning Center issued a national tsunami warning. After the volcano erupted again on the 15th, Tonga's national Tsunami Warning Center issued a tsunami warning again and called on people to stay away from beaches and low-lying areas along the coastline. Tonga Meteorological Bureau said that the whole territory of Tonga is threatened by tsunami, rainstorm, flood and strong wind. The volcano erupted on the 15th, causing seawater to pour back. The main streets of Nukualofa, the capital, were flooded, and many buildings were flooded. In the evening, the power failure in the capital Nukualofa reduced contact with the outside world. All domestic flights in Tonga were cancelled on the 15th. Multinational tsunami warning On the 15th, the volcano erupted with great power, and the sea water activity in some areas of Fiji, Samoa, Vanuatu and other countries was abnormal. These countries urgently issued a tsunami warning. New Zealand's national emergency management authority issued a warning on the 15th that its northern, eastern coastal areas and the west coast of South Island may be hit by huge waves. It is recommended that people stay away from ports, rivers and estuaries. The Australian meteorological agency issued a tsunami warning immediately after the eruption of Tonga volcano, covering many states and islands along the eastern coast of Australia. The Australian Meteorological Bureau said on the 16th that the shock wave propagation speed of the volcanic eruption exceeded 1000 kilometers per hour, and the atmospheric pressure in Australia changed significantly. Data show that the wave height near Norfolk Island is 1.72 meters, and the wave height in the gold coast is 0.82 meters. Japan's Meteorological Agency issued a tsunami warning for some areas such as the Amami islands on the 16th. As of the morning of the 16th, the maximum wave height caused by the tsunami off the coast of Japan appeared near Amami City, Kagoshima Prefecture, with a wave height of about 1.2 meters; In most other Pacific coastal areas, waves are less than 1 meter high. The tsunami had little overall impact on Japan. As of the morning of the 16th, a total of 230000 people in 8 counties of the country had issued "asylum instructions", and only one person was slightly injured during asylum. In Kochi county and Tokushima County, 10 and 5 fishing boats capsized respectively. A tsunami warning was issued on the 15th in some parts of the west coast of the United States, including Hawaii and the coastal areas of Washington and Oregon. According to the official twitter of the Pacific Tsunami Warning Center of the National Meteorological Administration, there are only minor floods caused by the tsunami on all Hawaiian Islands, no damage reports have been received, there are slight changes in sea level, and strong currents in some coastal areas may last for several hours. Sailors and swimmers need to be extra careful. The National Weather Service said there may continue to be strong currents in some areas along the coast of Washington and Oregon. The national emergency office under the Ministry of the interior of Chile issued a tsunami warning to most parts of the Pacific coast and Pacific Islands on the 15th, evacuating people on the coast and beach. Chile's naval hydrology and oceanography bureau announced that iquik and other places in the north of the country encountered waves nearly 2 meters high, and Chile is not affected at present. Chilean authorities will continue to monitor the changes of sea tides through 47 monitoring stations along the coast. The eruption may continue Kula, chief geologist of Tonga geological department, said that the energy released by the volcanic eruption on the 14th was about seven times that of the eruption on December 20, 2021. The eruption on the afternoon of the 15th was also powerful. A large amount of volcanic ash quickly rose into the air with a huge roar. The whole territory of Tonga was quickly covered by volcanic ash. It was dark early at 17:00 on the same day, and the visibility was very low. Shane Cronin, a professor at the University of Auckland, New Zealand, said on the 16th that the scale of the volcanic eruption on the 15th was much larger than the two earlier eruptions on December 20, 2021 and January 13, 2022. A large amount of fresh magma containing gas erupted from the crater, and the shock wave passed through thousands of kilometers. The eruption also triggered tsunamis in Tonga and neighboring Fiji and Samoa. These signs show that the crater of the incident has awakened, and the active period of eruption can last for weeks or even years. It is not clear whether it has reached the peak of eruption at present According to Japan's Yomiuri Shimbun, Professor Wenyan Imamura of Northeastern University believes that the large-scale wave height change on the coast of Japan may be caused by the shock wave generated by the massive eruption of Tonga volcano. Volcanic eruptions cause dramatic changes in pressure, which may affect the change of tide level. The tsunami was triggered by volcanic eruption rather than earthquake. The mechanism of tsunami is unknown, so it is more difficult to predict tsunami. (outlook new era)