Since communication with the Pacific state of Tonga is still difficult at best, the full extent of the disaster can only be estimated slowly. What is certain is that after the Hunga Tonga-Hunga Ha’apai erupted on January 15, a massive ash cloud fell on the archipelago, destroying crops and rendering drinking water supplies at least partially undrinkable. Tsunamis, which are said to have been up to 15 meters high in some places, also severely damaged many houses and infrastructure. However, based on satellite images and various measurement data, the picture of the most severe volcanic eruption of the last 30 years is becoming clearer and clearer. As the British National Center for Earth Observation (NERC) reports, the ash clouds during the eruption even reached the stratopause of our atmosphere at a height of more than 50 kilometers.
The so-called screen of the ejected ash spread out mainly over a distance of 35 kilometers, but in the central area the force of the eruption chased the material up to a height of 55 kilometers. It even reached the stratopause or layers of the atmosphere above it: Such heights have not been measured in any other known volcanic eruption. However, the bulk of the ejecta remained at lower elevations and spread sideways, causing heavy ash fall on the surrounding islands. In all, Hunga Tonga released about a cubic kilometer of material, about twice as much as Mount St. Helens did when it erupted in 1980.
Using satellite data, scientists estimate that 400,000 tons of sulfur dioxide entered the atmosphere. This cloud began drifting westward with the prevailing winds and spreading across the globe. Nevertheless, experts suspect that the quantity is not sufficient to have a lasting effect on the climate in the coming years. For example, the 1991 eruption of Mount Pinatubo in the Philippines released 50 times more sulfur dioxide and subsequently resulted in slightly lower average global temperatures. A similar effect is not expected this time.