Fact Check-Tonga volcanic eruption was not a nuclear explosion

The eruption at Hunga Tonga Hunga Ha’apai volcano on Jan. 15, 2022, was volcanic and not a nuclear explosion, despite claims made online.

The sea-level eruption was heard 2,300 km way in New Zealand and sent tsunami waves across the Pacific Ocean ( here ), ( here ).

Some took to social media claiming that it was not a volcanic eruption as reported, but a nuclear blast.

One user shared a low-resolution clip on TikTok claiming to show satellite footage shortly before the eruption, with a “white object” entering the sea. Some used the clip as proof that this was not an eruption, but a nuclear explosion ( here ).

The clip had more than 1.1 million views at the time of writing while the video was also shared to Twitter, with more than 100,000 views ( here ).

One user who shared a link to the TikTok clip on Facebook said: “Something ain’t right” ( here ).

Other examples of the claim online can be seen ( here ), ( here ), ( here ), ( here ).

However, there is no evidence of a nuclear blast, experts told Reuters, while there are myriad signs of a significant volcanic eruption.

“The immediate eruption was captured by the US GOES-17, Japan’s Himawari-8 and Korea’s GK-2A. It was also captured by a Chinese satellite (FY-4B) but that data is not public as the satellite is still undergoing post-launch testing. Several hours after the eruption various other satellites overflew the volcano,” Dr Simon Proud, research fellow at the National Centre for Earth Observation (NCEO), University of Oxford, told Reuters ( ), ( ), ( ).

“The three satellites I mention above all show the same story: An incredibly powerful volcanic eruption that began at approximately 4am UTC,” Proud said. Slight cloud cover is viewable in images at 03:50 UTC. “I suspect that is the beginnings of the eruption,” he added.

Meanwhile, the smallest object these satellites can detect is around 500m across, Dr Proud told Reuters, “so you can’t see a bomb and you can’t see the airplane carrying it. What we can see in the satellite data, though, are things we expect to see from volcanic eruptions: Sulphur dioxide and ash at very high altitudes. These would not be present from a nuclear bomb. These volcanic signatures have been seen both by the satellites above and by various other satellites (American, Chinese, Japanese, European, etc) in the subsequent days.”

There are other signals that are detected when a volcano erupts.

“The eruption of Hunga Tonga-Hunga Ha'apai has produced ample physical evidence for scientists to study, including volcanic ash blanketing nearby islands, a SO2 (sulfur dioxide) plume that has carried to Australia, a 30km-high eruption column that reached the stratosphere, seismographic signals characteristic of a volcanic eruption, tsunami generated from a single point source, and satellite confirmation of both an eruption and post-eruption destruction of the volcano itself. This is a significant volcanic eruption, and all of the effects we see are in keeping with how we know eruptions behave,” volcanologist Jess Phoenix told Reuters ( ).

The eruption occurred at a known volcano site, a spokesperson for the United States Geological Survey (USGS) told Reuters. Tonga sits along the subduction zone between two tectonic plates, the Pacific and Indo-Australian ( here ), ( here ).

A satellite view of the caldera can be seen in a report by the United Nations Institute for Training and Research (UNITAR) ( ).

There have been five confirmed reports of previous activity, in 1912, 1937, 1988, 2009 and 2014 ( here ), while the volcano has been erupting intermittently from December 29, 2021, to January 4, 2022 ( here ).

During the eruption, sulfur dioxide (SO2) was detected in the plume ( here ). Magma includes SO2, so it is often detected at volcanoes. SO2 is not detected in nuclear blasts, the USGS spokesperson added ( here ). No radioactive particles were detected, as would be expected following a nuclear explosion ( here ).

Copernicus atmospheric monitoring of SO2 emissions following the eruption can be seen ( here ).

Seismic and infrasound signals are also consistent with a volcanic eruption and not a nuclear blast, the USGS spokesperson said ( here ).

Sentinel-2 satellite imagery of the aftermath of the eruption can be seen ( here ), ( here ), ( here ).

International monitoring body, the Preparatory Commission for the Comprehensive Nuclear-Test-Ban Treaty Organization’ (CTBTO Preparatory Commission) also did not detect any signs that a nuclear weapon was detonated.

‘’The CTBTO makes data from its seismic, infrasound, hydroacoustic and radionuclide technology networks that form the International Monitoring System available to all States Signatories. This data and products can be used to determine whether an event is of natural origin or not. In the instance of the Hunga Tonga-Hunga Ha’apai eruption all infrasound stations on the IMS recorded the explosion, but no radionuclide activity related to this explosion was detected on any of the radionuclide stations,’ a spokesperson for the CTBTO told Reuters.

More information pertaining to the CTBTO monitoring regime can be seen ( here ), ( here )


False. The Hunga Tonga Hunga Ha’apai volcano erupted on Jan. 15, 2022. It was not a nuclear explosion.

This article was produced by the Reuters Fact Check team. Read more about our fact-checking work here.