In January 2022, the most powerful and explosive volcanic eruption recorded in history produced the largest plume ever of steam and ash.
The tall column that rose from Hunga Tonga Ha’apai reached an incredible height of 57 km (35 miles) above the sea level.
It is the largest ever volcanic eruption to penetrate the stratosphere in order to reach the mesosphere.
“It’s an amazing result, as we have never seen any cloud this high before,” Simon Proud, an atmospheric scientistOxford University
This shouldn’t come as a surprise, considering the eruption took place One of the most powerful volcanic eruptionsHumanity has never seen anything like it. It took some detective work to accurately measure the plume’s height.
The temperature profile of satellites making infrared observations is used to estimate the height of a volcanic cloud. These satellites are capable of detecting volcanic plumes because thermal emission (or heat) produces infrared radiation.
Because plumes travel through the troposphere, the layer closest to Earth and the one that we live in, they lose heat. Therefore, it is possible to use the temperature at the top to calculate height.
However, the plume will reach the stratosphere at an average altitude around 2,500 feet. 12 kilometersThis strategy can lose accuracy as the plume’s temperature profile changes and becomes warmer. Proud and his team of researchers took a different approach.
frameborder=”0″ allow=”accelerometer; autoplay; clipboard-write; encrypted-media; gyroscope; picture-in-picture” allowfullscreen>
Although satellite data was still used by the researchers, the measurement was made using parallax. Parallax is a phenomenon that can be seen if you close your eyes and watch objects shift side-to-side compared to their background.
It is the difference in the apparent positions of two objects when they are seen from different directions. This is the basis for depth perception in binocular sight. Our brain processes information from both eyes and calculates distance to objects. Parallax can be used to calculate Distances of all kinds.
Researchers used data from three geostationary satellites to obtain parallax measurements for the Hunga Tonga Ha’apai volcano eruption. They took images every ten minutes from various positions on low-Earth orbit.
Proud and his colleagues calculated that the plume had reached a height of 57 kilometers. This is very close to what NASA scientists calculated at a 58-kilometer altitude. Return to JanuaryData from two geostationary orbital satellites.
Mount Pinatubo, Philippines, was the previous highest recorded volcanic plume. 1991 eruptionA plume was formed that extended as high as 40 kilometersIn altitude
It is a bit puzzling that the Hunga–Tonga plume has a higher height than the Mount Pinatubo eruption. Both eruptions were rated as a 6 on VEI scale.
This question has an easy answer. The maximum height for the Hunga Tonga plume, if measured using Mount Pinatubo techniques would have been approximately 39 kilometers.
We don’t yet know the mechanism for Mount Pinatubo reaching such high altitudes, even if its plume was higher than we measured. This could be an interesting topic.
We don’t even know how a volcanic plume that high would affect the mesosphere. Since no other volcanic plume has been seen reaching such heights, we can only speculate that the effects are indirect.
The Hunga-Tonga plume was topped by a hazy substance. It is not known what it is or how long it will stay there.
This means we have to do more to understand this amazing and terrifying event.
“We would also like to apply the technique to other eruptions, and create a dataset with plume heights that can then be used by volcanologists to model the dispersion and combustion of volcanic ash in our atmosphere,” Andrew Prata is an atmospheric physicistOxford University
“We have further science questions to answer: How did the Tonga plume rise so high? What will the climate impact of this eruption be? What was the composition of the plume?
The research was published in Science.
