The huge amount of water vapor is about 10% of the normal amount of water vapor found in the stratosphere, equal to more than 58,000 Olympic-sized swimming pools.
“We’ve never seen anything like it,” said atmospheric scientist Luis Millán, who works at NASA’s Jet Propulsion Laboratory. Millán led a study of the water that the volcano sent skyward. The team’s research was published in Geophysical Research Letters.
The volcano sent steam and gases to a record height
The Jan. 15 eruption came from a volcano that is more than 12 miles wide, with a caldera about 500 feet below sea level. A day earlier, Tongan officials reported that the volcano was in continuous eruption, sending a 3-mile-wide plume of steam and ash into the sky. Then came the big explosion, sending ash, gases and vapors up to 35 miles—a satellite-era record—into the atmosphere.
Drone and other videos from that day show the dramatic scale of the eruption, as the volcano shot an impossibly wide plume into the sky. The powerful explosion sent a pressure wave circling the Earth and caused a sonic boom that was heard as far away as Alaska.
The sheer amount of water will likely raise the temperature
Past large volcanic eruptions have affected the climate, but they usually lower temperatures because they send light-scattering aerosols into the stratosphere. These aerosols act as a kind of bulky layer of sunscreen. But since water vapor traps heat, the Tonga eruption could temporarily raise temperatures a bit, the researchers said.
It usually takes about 2-3 years for sulfate aerosols from volcanoes to fall from the stratosphere. But the water from the Jan. 15 eruption could take 5-10 years to fully dissipate.
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Given this time frame and the extraordinary amount of water involved, Hunga Tonga-Hunga Ha’apai “may be the first volcanic eruption observed to affect climate not through surface cooling caused by volcanic sulfate aerosols, but rather through of surface warming,” the researchers said. their paper.
NASA says the data for the study came from the Microwave Limb Sounder (MLS) instrument on the Aura satellite, which measures water vapor, ozone, aerosols and gases in Earth’s atmosphere.
The volcano interrupted the “heartbeat” of water in the stratosphere
The January 15th eruption markedly disrupted annual patterns of water in the stratosphere (which also holds most of the atmosphere’s ozone).
The normal mechanism by which water rises into the stratosphere is so reliable that researchers refer to it as a kind of tape recorder, recording annual temperature cycles through alternating bands of dry and moist air rising from the tropics.
January is usually the middle of the dry season in this seasonal cycle – but then Tonga’s volcano erupted in the South Pacific Ocean, suddenly injecting a huge amount of water high into the atmosphere.
“By short-circuiting the path through the cold spot, [Hunga Tonga-Hunga Ha’apai] has disrupted this “heartbeat” signal in the planet’s normal atmospheric water, the researchers said.
They recommend careful monitoring of the water from the volcanic eruption, both to predict its impact in the near future and to better understand how future eruptions might affect the planet’s climate.
