A new study reveals that the Tonga volcanic eruption could lead to unusual weather patterns throughout this decade.
The Hunga Tonga-Hunga Ha’apai volcano erupted on January 15, 2022, in the Kingdom of Tonga in the Pacific Ocean. This event triggered a tsunami that resulted in warnings across the entire Pacific Basin and sent sound waves around the world multiple times.
Tonga Volcano Eruption Releases 150 Million Tons of Water Vapor
A recent study published in the Climate Journal explored the climatic impact of this eruption. Findings indicate that the Tonga volcano may have caused a significant ozone hole last year and could make the summer of 2024 much wetter than expected.
The eruption could also have long-lasting effects on winter weather for years to come.
Typically, volcanic smoke, particularly sulfur dioxide contained in the ash cloud, cools the Earth’s surface for a short period. However, this was not the case with Hunga Tonga.
Aerial view of the Hunga Tonga volcanic eruption in 2022 – (Photo: NOAA/SSEC/CIMSS/REUTERS).
As an underwater volcano, Hunga Tonga produced little smoke but a significant amount of water vapor—approximately 100 to 150 million tons, equivalent to 60,000 Olympic swimming pools. The immense heat from the eruption converted large volumes of seawater into vapor, which was then propelled high into the atmosphere by the force of the eruption.
All that water eventually entered the stratosphere. Water vapor in the stratosphere has two main effects: it supports chemical reactions that destroy the ozone layer, and it is a potent greenhouse gas.
There is no precedent in human observations of volcanic eruptions to know how all that water will impact the climate and for how long. The reason is that the only way to measure water vapor throughout the stratosphere is via satellite.
Using Climate Models for Forecasting
Stratospheric science experts worldwide began examining satellite images from the first day of the eruption. Some studies focused on more commonly observed effects of volcanic eruptions, such as sulfate aerosol levels and their evolution post-eruption. Others focused on the potential impacts of water vapor, with some studies incorporating both aspects.
However, no one truly knows how water vapor in the stratosphere will behave. How long will it remain in the stratosphere? Where will it go? And most importantly, what does this mean for the climate while the water vapor is still present?
These are precisely the questions that researchers aimed to answer. They wanted to understand the future, but unfortunately, it was beyond measurement. This is why they turned to climate models, specifically designed to forecast future conditions.
The scientists conducted two simulations using the same climate model. In the first scenario, they assumed no volcanic eruption occurred, while in the second scenario, they manually added the equivalent of 60,000 Olympic swimming pools of water vapor into the stratosphere. They then compared the two simulations, knowing that any differences were due to the added water vapor.
As a result, the research team discovered a massive ozone hole from August to December 2023, at least partially attributed to Hunga Tonga. Since the ozone hole persisted until the end of December, many weather changes occurred during the summer of 2024.
For Australia, scientists predict a higher likelihood of a wetter summer, which is entirely contrary to what people typically expect when they hear about the El Niño phenomenon.
The eruption has some surprising long-term effects in various regions across the planet. For the northern part of Australia, winters are expected to be colder and wetter than usual, lasting until around 2029.
In North America, winters are forecasted to be warmer than usual, while in Scandinavia, simulation models predict colder-than-normal winters.
Researchers emphasize that, like any other climate model, theirs is not perfect. The team also did not account for any other effects, such as the El Niño-La Niña cycles.
This is just one study and a way to assess the impact of the Hunga Tonga volcanic eruption on climate and weather. However, they hope the research will spark interest among the scientific community to further investigate what such a large amount of water vapor in the stratosphere could mean for our climate.
