- A catastrophic eruption with the potential for a global cataclysm could happen at any time
- Eruptions that reduce air temperature
- The influence of volcanoes on climate is increasing
A catastrophic eruption with the potential for a global cataclysm could happen at any time
Volcanoes wake up on Earth every year, but the planet hasn't had a truly catastrophic eruption in centuries. Despite this, according to CNN, many scientists are talking about the likelihood of a new global cataclysm that will affect the climate, the economy and the geopolitical situation around the world. And it could happen at any time.
The Tambora volcano eruption in Indonesia in 1815 is considered one of the biggest such disasters. The awakening volcano released unusually high levels of ash and sulfur dioxide into the atmosphere, leading to a volcanic winter in the Northern Hemisphere, the effects of which were felt for several years. The clouds that shrouded the planet blocked the sun's rays, cooling the climate.
The following year, 1816, has gone down in history as the 'year without a summer'. In Western Europe and North America, plummeting temperatures led to the death of crops and mass famines and epidemics that claimed tens of thousands of lives[1].
More than 200 years after the Tambora explosion, the world could face a similar global catastrophe again, scientists say. Markus Stoffel, professor of climatology at the University of Geneva, estimates that the chances of such a large-scale eruption in the 21st century are about 1 in 6. According to the expert, it will happen in a world that has changed dramatically and will lead to "climate chaos" because humanity has no plan to deal with such things.
Eruptions that reduce air temperature
Volcanos can release huge amounts of tiny particles into the atmosphere, forming clouds of sulphuric acid that reflect sunlight
Volcanoes have a huge impact on the Earth, "manifesting" themselves in forming continents and influencing climate change. When they erupt, they release a mixture of lava, ash, and gases into the atmosphere, including carbon dioxide, which does little to warm our planet. However, its impact is negligible compared to the activities of fossil fuel users.
Gases such as sulfur oxide have a much greater impact on climate change. Volcanoes can displace it at high altitudes - all the way up to the stratosphere, where planes fly. Here, the displaced gases form tiny aerosol particles that scatter sunlight, which no longer reaches the Earth's surface but is reflected back into space. In a powerful eruption, these particles will be carried worldwide for years[2].
Scientists can use satellites to estimate the amount of sulfur oxide entering the atmosphere. For example, in 1991, the Pinatubo volcano on the Philippine island of Lusan emitted about 15 million tonnes of gas. It was not as powerful as Tambora, but its effects were still felt worldwide, with a sulphuric acid haze that lowered the ambient temperature by +0.5°C.
Experts assess the impact of eruptions from the distant past using data from studies of glaciers and tree bark, which hold information about the climate of centuries past.
For example, the increased acidity of ancient ice sheets in Greenland and Antarctica suggested that the eruption of the Samal volcano in Indonesia in 1257 was at least twice as strong as the Tambora eruption in terms of the amount of ash emitted. This catastrophe is thought to have been one of the causes of the so-called Little Ice Age, a global cooling between the 14th and 19th centuries.
Volcanic eruptions affect temperature and precipitation: sulphuric acid clouds create an imbalance between land and ocean warming, drying out monsoon currents.
The influence of volcanoes on climate is increasing
In today's world, and due to global climate change, the effects of powerful eruptions will be felt much more strongly.
"The present world has become more unstable, so the impact could be much worse than it was in 1815," warned Michael Rampino, a professor at New York University who studies the link between volcanic activity and weather changes.
Strong eruptions in warmer climates will have an even more significant cooling effect. As temperatures rise, air circulation in the atmosphere speeds up, meaning that sulfur oxide clouds dissipate more quickly. The smaller the size of aerosol particles, the more strongly they reflect sunlight, increasing the cooling effect[3].
Finally, climate change can affect the behavior of volcanic systems themselves. Melting ice can increase the frequency and severity of eruptions, as their loss reduces pressure on the earth's surface, allowing magma to rise faster. Precipitation can also affect its activity, as moisture penetrating deep into the ground reacts with magma to trigger new eruptions.
The next catastrophic eruption could happen anywhere. Scientists are keeping a close eye on several regions, including Indonesia - the most seismically active area of our planet, with the most active volcanoes worldwide.
Also on the worrying list is the Yellowstone Super Volcano in the United States, which has been dormant for hundreds of thousands of years but is becoming more active yearly. If it wakes up, the Earth could face an unprecedented catastrophe that would dwarf any eruption known to mankind.
Finally, a supervolcano slowly awakens in the Fleiger Fields, near Naples, Italy. A mega-eruption occurred there around 40,000 years ago, triggering global climate change and possibly leading to the extinction of Neanderthals.
Today, up to 800 million people live near active volcanoes and are in constant danger because a powerful eruption can destroy entire cities. However, in the long term, the consequences could be far more severe.
A 1°C drop in temperature may seem insignificant, but it is an average, so the variations will be much more severe in some regions. For example, studies have shown that the eruption of the Okmok volcano in Alaska in 43 B.C. This could have cooled southern Europe and northern Africa by 7 °C.
According to a study by the insurance company Lloyd's, cooling, lack of sunshine, and changes in rainfall could simultaneously adversely affect several regions of the global food industry, including the US, Russia, and China. This could lead to global food shortages, political tensions, and wars. The human toll would be enormous, and the economic losses in the first year after the disaster alone could exceed USD 3.6 trillion.
Megavolcanic eruptions cannot be avoided, but there are ways to prepare for them, says Markus Stoffeli. He calls on experts to assess worst-case scenarios, carry out stress tests, and draw up disaster action plans, from mass evacuations to food security.
