Tonga volcano is followed by Mount Fuji? We asked the internationally renowned volcanologist

On January 15, local time, a violent eruption of the submarine volcano on Aha Apai Island in Tongahun triggered a tsunami that caused catastrophic damage to the country, causing 3 deaths and some injuries, and the number of casualties may increase in the future.

The Government of Tonga has declared a state of emergency in the country.

In this regard, on January 19, a reporter from the Beijing News contacted Roberto Sulpizio, a volcanologist at the International Association of Volcanology and Internal Earth Chemistry (IAVCEI). He said that this is not the worst volcanic eruption in the past 30 years, and this volcanic eruption in Tonga will not have a great impact on the climate.

On January 19, the Beijing News "Earth Wired" interviewed Roberto Sulpizio.

"Not the worst volcanic eruption in the last 30 years"

Beijing News: On January 15, Tonga's submarine volcano erupted, triggering a transoceanic tsunami, which was reported to be the worst volcanic eruption in the past 30 years. Do you agree with this view? How would you rate the severity of this eruption?

Roberto Sulpizio: The undersea volcanic eruption in Tonga was a major event, but it was not the worst in the last 30 years. For example, the 2011 eruption of Mount Puyeve in Chile was more severe than the undersea volcano in Tonga.

The 2011 eruption of Chile's Mount Puyehue severely affected Chile and southern Argentina, and Australia's air traffic was disrupted, releasing at least two orders of magnitude more energy than The Tonga submarine volcano. But this time Tonga is an undersea volcano that releases energy into the water, pushing the sea away, triggering a tsunami and posing more risk.

Beijing News: Volcanic eruptions generally cause earthquakes, and it is very rare to cause tsunamis?

Roberto Sulpizio: There are two kinds of volcanic eruptions, when on the ground, volcanic eruptions in the solid part of the earth's crust trigger earthquakes, submarine volcanoes have the risk of causing tsunamis, and it is not uncommon for submarine volcanoes to trigger tsunamis.

Whether there are also large-scale eruptions depends on future magma data collected

Beijing News: Can we predict volcanic eruptions? The day before the tonga submarine volcano erupted (January 14), some institutions detected lightning around the volcano. Can we make predictions from these pre-eruption signs?

Roberto Sulpizio: In principle, like natural phenomena such as earthquakes, we can predict volcanic eruptions, but the exact timing of their eruptions is difficult to predict. Most of the world's volcanoes are under surveillance, but this kind of monitoring also only means that we know that volcanoes are in certain motion at some point.

In Tonga, its volcano monitoring system has been greatly improved, and the scientific community is recording some volcanic mass movements, but it is difficult to judge whether there will be a similar eruption next.

Beijing News: The undersea volcanic eruption in Tonga is expected to last for months or even longer. We still can't predict whether there will be a bigger eruption in the future?

Roberto Sulpizio: Judging by historical data on eruptions, this eruption could last for months or even years. However, this also depends on the amount of magma stored by the volcano. Now that we have colleagues monitoring the activity of tonga's undersea volcanoes, they may be able to tell in the coming days whether the volcano's magma volume will (continue) lead to a massive eruption.

Beijing News: How is the monitoring and prediction of submarine volcanoes carried out? Will satellites be used?

Roberto Sulpizio: Satellites will be used, but because the sea water blocks submarine volcanoes, most of the submarine volcano monitoring predictions are carried out through seismic monitoring systems. Cracks are created as magma passes through the solid parts of the volcano, which in turn produce seismic waves. We judge by monitoring seismic signals from solid parts of the volcano on the ocean floor to see if they vibrate.

Volcanic ash has a negative impact on people's lives

Beijing News: The amount of volcanic ash in Tonga this time is extremely large. In addition to the volcanic ash affecting the local people's access to drinking water, what impact will the volcanic ash have on the lives of the local people? In this case, how else can people protect themselves?

Roberto Sulpizio: Volcanic ash has a negative impact on people's lives, harming the lungs or other parts of the respiratory system. In this case, we would advise people not to go out and wear a mask when they go out. There is also the problem of water pollution, which also depends on whether the local reference water resources are open or not, but we can mitigate its effects by cleaning the volcanic ash on the surface.

But because Tonga's main island is now completely covered in volcanic ash, and the capital, Nuku'alofa, is also deeply affected, large-scale volcanic ash may remain for several days, and it will take some time.

Roberto Sulpizio, a volcanologist at the International Society of Volcanology and Internal Earth Chemistry (IAVCEI). Courtesy of respondents

Beijing News: There are many comments on the Internet comparing it to the eruption of Mount Pinatubo in the Philippines in 1991, which caused the average global temperature to drop by 0.5 °C in 1991 and 1992 for two years, bringing about a "summerless year" and affecting the development of La Niña's state. What do you think of this view? Will this time lead to such a big impact?

Roberto Sulpizio: This statement is exaggerated. When Mount Pinatobo erupted in the Philippines in 1991, several cubic kilometers of ash erupted into the air, while the Tonga submarine volcano has so far spewed millions of cubic meters of volcanic ash, and the difference between the two is still very large (1 cubic kilometer = 1×103 million cubic meters). In addition, the main eruption phase of Tonga's submarine volcano lasted about 8 minutes, while Pinatubo volcano lasted for several hours.

Therefore, from the first stage of the eruption, the Tonga submarine volcano will not have a huge impact on the climate, or affect the state of La Niña, everything depends on the progress of the Tonga submarine volcano.

(Note: La Niña, which means "little girl" in Spanish, also known as anti-El Niño, refers to the phenomenon of sustained abnormal cooling in the eastern and central equatorial Pacific Oceans, manifested as the surface temperature of the seawater is more than 0.5°C below the average climate, and lasts for more than 6 months.) ）

Volcanoes operate on millennia and are not directly linked to global warming

Beijing News: In addition to the Tonga volcano, there are also comments that Japan's Mount Fuji volcano has signs of eruption, will we enter a period of frequent volcanic eruptions next?

Roberto Sulpizio: I don't think the volcano has entered a special period of awakening now.

In the long run, volcanic activity around the world has been similar. The current "volcanic awakening period" has also appeared many times in the past, but most of them are cycled in the same cycle. The operation of the volcanic system is calculated in millennia, not within the daily time frame. Based on historical surface data, there is no sign of recent volcanic activity entering an active phase.

In addition, Mt. Fuji is an active volcano, so it will erupt one day. But Mt. Fuji is one of the most heavily monitored volcanoes in the world, and if it erupts, the public will certainly be notified, and I don't think Mt. Fuji will erupt in the near future.

Beijing News: Since 2021, extreme weather phenomena have occurred frequently, such as floods in Europe, heat waves in North America, and recent tornadoes in the United States, are these extreme weather phenomena related to volcanic eruptions?

Roberto Sulpizio: There is no direct connection between these phenomena. Volcanoes are obviously related to atmospheric dynamics, but the scale between these phenomena you just mentioned and volcanic activity is completely different. Atmospheric activity is measured in days and weeks, and to "activate" a volcano, its magma production and eruption takes years or centuries. The atmosphere changes much faster than volcanoes.

Volcanic eruptions have indeed been linked to climate change before, such as the "summerless year" in the early 19th century, when large-scale eruptions of volcanoes prevented solar rays from reaching the Earth, but this single phenomenon cannot be generalized.

Beijing News: What is the connection between volcanic eruptions and global warming?

Roberto Sulpizio: There is no direct link between global warming and volcanoes. Global warming is actually related to the release of carbon dioxide and organic matter into the atmosphere by human activities, and although volcanoes release large amounts of methane and carbon dioxide into the atmosphere every day, this is a natural activity, and the cause of global warming is the additional greenhouse gases released by humans.

Beijing News reporter Hou Wuting Yao Yuan

Edited by Zhang Lei, Proofreader Wu Xingfa