Tonga Volcano Eruption: Impact on Global Climate & Economy

Around 12:20 noon on January 15, Beijing time, a large-scale volcanic eruption occurred in the waters of Tonga, a South Pacific island country. The volcanic eruption disrupted the Internet connection in Tonga, and the United States, New Zealand, Japan, Australia and other countries also issued tsunami warnings of varying degrees. Satellite detection results show that the volcanic ash reaches an altitude of about 28 kilometers, and even mushroom clouds can be seen on the satellite cloud map.

According to media reports, Fijian Chinese living 800 kilometers away from the volcano said that when the volcano erupted, the local feeling was very obvious. According to the “Volcanic Eruption Intensity Index” (VEI), the intensity of the Tonga volcanic eruption is likely to reach the upper end of the VEI5 level, and may even reach the VEI6 level, which may be one of the strongest volcanic eruptions in the world since Pinatubo, Philippines in 1991. .

Intense volcanic eruptions of magnitude 5 and above are rare. According to the statistics of meteorological enthusiasts, since the 19th century, there have been 11 strong volcanic eruptions of magnitude 5 and above (6 at magnitude 5, 4 at magnitude 6, and one at magnitude 7), among which the eruption of Mount Tambora in 1815 was the most After a strong volcanic eruption, in 1816, the famous “Year without Summer” appeared in Europe and North America.

Volcanic eruptions have seriously affected human activities on many occasions, some paralyzing air routes, and some affecting the entire human civilization. After the Tonga volcano erupted, speculation abounded that a “Year without Summer” could come. But judging from the current situation, there is a high probability that the “year without summer” will not occur.

Years without summer? Now there will be no

The reason why volcanic eruptions affect the climate is that sulfur dioxide gas from volcanic eruptions reaches the stratosphere, and in a short period of time (one or two months), sulfuric acid aerosols are formed, which are transported to all parts of the world with the stratospheric circulation. Because of the stable stratospheric circulation, sulfuric acid persists for longer (more than a year), causing near-surface temperature reductions by blocking solar radiation.

Judging from the latest satellite monitoring data, the volcanic ash from the submarine volcanic eruption in the waters near Tonga reached a maximum of about 28km, which has reached the middle and lower layers of the stratosphere. According to Sentinel5P/TROPOMI’s estimates of sulfur dioxide entering the stratosphere, about 400,000 tons of sulfur dioxide entered the stratosphere.

This numerical distance can have an impact on the global climate, and there is still a very large gap. Compared with the eruption of Mount Tambora that caused the “Year Without Summer” in 1816, the magnitude gap is huge. “Voice of the Chinese Academy of Sciences” judged that if there is no stronger eruption in the later period, the impact of this volcanic eruption on the global climate is very limited, and it is impossible to cause a “year without summer”

However, it is necessary to pay attention to the direction of the subsequent eruption of the Tonga volcano. Judging from several consecutive eruption columns exceeding 15,000 meters, it cannot be ruled out that it will use several 5-level eruptions to make up a “6-level equivalent”.

What are the economic impacts?

Although there is a high probability that there will not be an abnormal climate with snow and ice in the midsummer of 1816, the negative impact that the largest volcanic eruption in this century may bring to many industries is still worthy of attention.

According to the interpretation reports of relevant securities, agriculture and agricultural product supply chains, photovoltaics, and aviation industries may all be affected by volcanic activity.

Agriculture and Agricultural Products Supply Chain

According to a study by the US Geological Survey, several large-scale volcanic eruptions over the past century have injected large amounts of sulfur dioxide aerosols into the stratosphere, increasing the reflection of solar radiation into space, causing the average temperature of the Earth’s surface to drop by about 0.5 degrees Fahrenheit, affecting the Lasts 1–3 years.

If the eruption of the Tonga volcano does not stop, the final intensity will reach VIE6 level, which may lead to global cooling in the next 1–3 years.

Global cooling is superimposed on the northern hemisphere this year, which is affected by the La Niña phenomenon. If the accumulated temperature is insufficient, the production of spring crops and fresh fruits and vegetables may decrease. In addition, corrosive volcanic ash could also be a blow to agriculture — according to the Geological Society of London, 1 cm of volcanic ash can completely destroy crops, and New Zealand, a major global agricultural exporter closer to Tonga, may be affected.

Countries such as New Zealand and Australia play an important role in the global supply chain of agricultural products such as dairy products, fresh vegetables and fruits, and are vulnerable to the secondary impact of another volcanic eruption.

Photovoltaic

After the eruption of Mount Pinatubo in the Philippines in 1991, a cloud of about 20 million tons of sulfur dioxide was injected into the stratosphere, reducing global sunlight by about 10% that year. If the ultimate impact of the Tonga volcanic eruption is similar, it may have some negative impact on global photovoltaic power generation.

Transportation industry

If the volcanic ash spreads over a large area, it may further affect the global aviation industry, reduce transportation efficiency and drag down the global supply chain. Some experts have also analyzed that if the Tonga volcanic eruption lasts for a long time, the volcanic ash formed will spread to a wider area, which will not rule out adverse effects on air transportation in the trans-Pacific region.

In 2010, the Eyjafjallajökull volcano in Iceland erupted. This VEI4 eruption produced a large amount of volcanic ash, which was blown by the wind to the European continent, forcing many important routes between Europe and the Americas to be closed within a few months.

Judging from the eruption of this Tonga volcano, the eruption site is in the southern hemisphere, and the impact on the northern hemisphere is relatively small, while southern Australia, southern Brazil, New Zealand, Argentina, Chile and South Africa in the middle and high latitudes of the southern hemisphere may bear the brunt of the impact.

In addition, since the volcanic eruption point is near the ENSO monitoring area, it is necessary to be alert to the impact of volcanic eruption on wind and ocean currents. If the volcanic eruption lasts for a long time, it may cause too much aerosol to enter the stratosphere, increasing the probability of extreme weather, thereby increasing the probability of extreme weather. It will adversely affect the good rate and yield of crops.

Originally published at https://www.tlw.com.