On January 15, 2022, the Hunga Tonga-Hunga Ha’apai volcano erupted, triggering a massive sonic boom and a tsunami that moved around the world. The eruption took place underwater, superheating seawater in the area and blasting an enormous amount of dirt, rocks, volcanic material, and water into the stratosphere. Now scientists have found that the eruption also removed part of the planet's ozone layer. The findings have been reported in Science.
The eruption of Hunga-Tonga Hunga-Ha'apai was among the most powerful explosions that have ever been recorded. During the eruption, trillions of grams of saltwater were injected into the atmosphere, where it reacted with atmospheric chemicals that contained chlorine. Researchers concluded that this caused a breakdown of ozone, or O3.
In this study, the investigators collected data by using balloons that had been outfitted with sensors. The balloons were released into the atmosphere from Réunion Island in the Indian Ocean, which is located near the eruption. This work was done five days after the eruption occurred. Initial data revealed that ozone levels in the resulting volcanic plume were about 30 percent lower than normal.
The balloons also continued to gather data from within the plume as it moved across the Indian and then Pacific Oceans. The total level of ozone depletion was found to be about five percent. This is the first time such a rapid depletion of the ozone layer has been recorded.
The researchers noted that a five percent drop is not very alarming, however, because this loss was local to a relatively small area, and not particularly significant when considering the ozone layer as a whole. For perspective, the portion of the ozone layer that sits over Antarctica is depleted by about 60 percent every year, noted the investigators.
It does emphasize the power of this incredible eruption, however. NASA has been monitoring the impacts of huge volcanic eruptions for almost 20 years, and in that time, only two other volcanic eruptions have released this much water into the atmosphere, and to such high altitudes.
