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When an underwater volcano in Tonga erupted in January, it spewed more than ash and volcanic gases; it also spewed 58,000 Olympic pools of water vapor into Earth’s atmosphere, according to a new study.
This water vapor could end up being the most destructive part of the volcano‘s eruption as it could potentially exacerbate global warming and exhaust the ozone layer, according to the study.
When the Hunga Tonga-Hunga Ha’apai volcano erupted on January 2. 15, it became the most powerful explosion on Earth in more than 30 years, with a equivalent force of 100 Hiroshima bombs. The explosion sent shock waves around the planet, causing a ring like a bell and generating tsunamis that battered neighboring ribs. A plume of ash and dust reached higher in the atmosphere than any other recorded eruption and triggered more than 590,000 lightning strikes in three days.
In the new study, researchers used data collected by NASA’s Aura satellite to estimate how much water has been pushed into the stratosphere, the second layer of Earth, which extends from 4 to 12 miles (6 to 20 kilometers) up to 31 miles (50 km) above the surface of the planet. The results revealed that 160,900 tonnes (146,000 metric tons) of additional water vapor had entered the stratosphere since the volcano erupted, reaching a maximum altitude of 33 miles (53 km), which is in the mesosphere. , the layer of the atmosphere that extends from the top of the stratosphere to an altitude of 53 miles (85 km).
This makes it the largest and highest injection of water into the stratosphere since satellites began taking measurements.
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“We estimate that the excess water vapor is about 10% of the amount of water vapor typically residing in the stratosphere,” which is the largest increase ever observed by scientists, the researchers wrote in the new article, published online July 1 in the journal Geophysical Research Letters. Water vapor can stay in the stratosphere for about half a decade, the researchers wrote.
It is not entirely surprising that the Tonga eruption injected a large amount of water vapor into the atmosphere, given that the explosion was triggered about 150 meters below the surface of the ocean, the researchers said. When the volcano erupted, seawater that came into contact with the erupting magma was rapidly superheated, resulting in large amounts of “explosive steam”, they wrote. This is one of the main reasons why the explosion was so powerful. However, this is the first time the amount of water has been accurately measured, and it turned out to be much higher than scientists had expected.
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Normally, large volcanic eruptions release large amounts of ash and gases, such as sulfur dioxide, which can create reflective compounds in the atmosphere. These volcanic byproducts can block sunlight from reaching the planet’s surface, which can cool the atmosphere. However, the Tonga eruption produced surprisingly low levels of sulfur dioxide compared to similarly sized explosions, and most of the ash it ejected quickly fell to the ground.
As a result, experts first estimated that the underwater explosion would have minimal effects on the Earth’s climate. But those estimates were based on the amount of ash and gas emitted from the volcano and didn’t account for all the excess water vapor, which could be just as problematic.
This excess water, the researchers warn, could have a radiant effect that could warm the atmosphere as much as greenhouse gas do. Because the water is likely to stick around longer than other volcanic gases, such as sulfur dioxide – which normally falls from the atmosphere within two to three years – the warming effect of the water is likely to last longer. longer than the cooling effects created by the gases.
This means the Tonga explosion is likely to be the first recorded eruption to cause a warming effect, rather than a cooling effect, on the planet, the researchers wrote.
The researchers also pointed out that such an increase in water vapor could decrease the amount of ozone in the stratosphere, potentially weakening the ozone layer that protects life on Earth from the sun’s harmful ultraviolet rays. Sun. Stratospheric water, or H2O, can break down into OH ions over time. These ions could react with ozone, which is made up of three oxygen atoms, to create water and oxygen. However, it is unclear how this will affect the ozone layer as a whole, the researchers wrote.
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However, the researchers also believe that increased water vapor could decrease the amount of methane in the atmosphere, which is one of the main greenhouse gases responsible for climate change. The same OH ions that react with ozone can also react with methane to produce water and a methyl radical (methane with one less hydrogen atom), which traps much less heat in the atmosphere than the methane. Hopefully, this potential reduction in methane could offset some of the warming caused by water vapor, the researchers wrote.
However, the study authors believe it is still too early to predict the exact climatic effects of the Tonga eruption. “Continued monitoring of volcanic gases from this and future eruption is essential to better quantify their different roles in climate,” the researchers wrote.
Originally posted on Live Science.