Knowing the Most Disastrous Forces of the Planet.

Imagine introducing a volcanic eruption that is so grandiose that it turns the sky black in several months, freezes the planet, and kills people on the continent level. We are not referring to the usual explosive volcano like the Mount St. Helens or the Vesuvius. 

We are discussing the supervolcanoes - the strongest and the most frightening geological process in the Earth. Although the concept may seem a disaster film plot, these giant volcanoes are not a figment of imagination, and it is essential to know them, although their eruptions are fortunately an infrequent occurrence.

What then is a supervolcano? A supervolcano is defined as a large depression on the ground in the form of a crater unlike the volcanoes that are typical of a cone like mountain. This caldera is created upon an eruption so massive that the surface of the magma chamber that has been emptied is falling. These systems are magma chambers that are large and contain thousands of cubic kilometers of molten rock sufficient to create destruction of world proportions. The term super volcano is a general term that denotes volcanoes that have occurred at least once with the Volcanic Explosivity Index (VEI) of 8 -the highest level on the scale, which results in an eruption of over 1,000 cubic kilometers of material.

Yellowstone of the United States is the most notorious supervolcano and probably the doomsday of geologists who are seldom sleeping. Yellowstone national park has a huge magma chamber underneath it and the park is actually a huge caldera. Although Yellowstone is known as geysers and hot springs, these are only superficial ways of identifying the heat and the pressure that is brewing under. Others that are known to be supervolcanoes are Toba in Indonesia, which happened to erupt around 74,000 years ago and may have dumped the earth into a volcanic winter, and the Long Valley Caldera in California.

Why is a supervolcano so significantly more hazardous than an ordinary volcano? The eruption size is the first determinant. A common eruption would affect an area or even a nation, but a supervolcano eruption would affect the world. This is a terrifying account of what might occur:

Catastrophic Ashfall: The first eruption would cause a gigantic ash, rock and gas plume into the atmosphere, hundreds of kilometers high. This ash would then be spread covering huge regions. Volcanic ash is made up of rocks and glass compared to the light campfire ash. It is coarse, rustic and dense. It would cause the roofs to collapse, damage crops, pollute water sources and make large portions of the land inhabitable in decades. The world would not be able to travel by air because of the problem of engine failure.

Global Climate Cooling (Volcanic Winter): The sulfur dioxide gases and fine particles released to the stratosphere would reflect sunlight back into space. This decrease in the amount of solar radiation hitting the earth would cause the world temperatures to decrease significantly and in a lasting manner - a volcanic winter. Farming would be reduced or completely lost and famine and social breakdown would occur on a massive scale. The impact may have lasting effects in years to come interfering with the ecosystem and the human population around the world.

Atmospheric and Environmental Alterations: The huge emission of gases, such as carbon dioxide, sulfur dioxide, and hydrogen sulfide, would acidify the rainfall and add to the acid rain that would more negatively affect crops, forests, and aquatic life. It would also be possible to temporarily deplete the ozone layer, which would augment the damaging UV radiation.

Geological Instability: The eruption itself would be accompanied with earthquakes of very strong power and possibly large landslides as the soil above the collapsing chamber of magma falls. Pyroclastic flows Pyroclastic flows are rapid streams of hot gas and rocks which would burn down all that they deposited during a range of hundreds of kilometers around the caldera.

Should we therefore ever be in terror? Luckily, no. Supervolcanic eruptions are very uncommon. In the case of Yellowstone, the previous super-eruption occurred approximately 630,000, 1.3 and 2.1 million years ago respectively. The period of occurrence is hundreds of thousands of years. Although such eruptions and hydrothermal manifestations are more prevalent at the locations of supervolcanoes, a full-scale super-eruption is not expected in the near future.

These geological giants are however being tracked by scientists all the time. In the case of Yellowstone, seismic sensors record the occurrence of earthquakes, GPS measures the deformation of the ground (a movement of magma) and gas sensors can measure the emissions. Any radical variation in these parameters would be an alarming factor and would give a certain warning though maybe less than ideal. This monitoring is not only aimed at predicting an eruption but also to have a better understanding of the activities that occur deep within the earth.

Although eruption of supervolcano is a threat to be feared, it acts as a strong reminder of the tremendous forces that happen to be below our feet. It highlights the vulnerability of our life on this planet and how interconnected our systems on this planet are. With further investment in scientific exploration and observation, there is hope that we will gain a better insight into these titanic threats, and eventually, we shall be able to intervene in order to lessen their possible effects. To date, we are able to enjoy the beauty of our active Earth, knowing that when in inactivity, these giants are the reminder of the raw untamed power of the planet.