Tonga eruption is the biggest and worst volcano crisis in human history. Here’s why

No volcano in human history has ever been so scary.

Rupendra Brahambhatt
Tonga eruption is the biggest and worst volcano crisis in human history. Here’s why
Tonga eruption

NASA Earth Observatory 

About 11 months have passed since the Hunga-Tonga-Hunga-Ha’apai volcano erupted, but the aftermath of this biggest volcanic event in human history continues to surprise us. To study the impact of the volcano in the Pacific region, a team of researchers from New Zealand and the UK mapped the 22,000 km2 area around the Tonga volcano. 

Findings from the Tonga Eruption Seabed Mapping Project (TESMaP) reveal that the Pacific seafloor has undergone massive changes due to the eruption, and it is no longer the way it used to be. The volume of material that came out of the volcano after the blast stands at 9.5 cubic km (2.3 cubic miles) in volume. This is more than required to construct 4,000 giant pyramids like those found in Egypt. 

Here is what the TESMaP project uncovered  

Erupted material volume from Tonga eruption as compared to that from other eruptions in the past.

We recently reported that the plumes of Tonga volcano went 57 km up in the atmosphere and landed somewhere in the mesosphere. These were the highest-ever recorded volcanic plumes in human history. The current study also confirms this fact and reveals that over 65 percent of the matter that came out of the volcano comprised rocks and ash.

According to the TESMaP survey, the eruption was so powerful that it resulted in pyroclastic currents (fast-moving mass formed by gases, lava, and ash), the debris of which could be found even 50 miles (80 km) far from the site of the explosion. The matter carried by the currents has a temperature of 1,832 Fahrenheit (1000 degree Celsius), and it was flowing at 435 miles per hour (700 km/h), nearly twice the speed of a formula one racing car.  

Surprisingly, the pyroclastic currents shook the Pacific seabed and led to tsunami waves, but they couldn’t destroy the side walls of the Tonga volcano. However, during their survey, researchers from the National Institute of Water and Atmospheric Research (NIWA) in Auckland found that the depth of the volcano’s crater has now increased by 700 meters.

The TESMaP project also highlights that although the currents did a lot of destruction, there were places right beneath the volcano site where life is still flourishing. One of the researchers and project director at NIWA, Dr. Kevin Mckay, told BBC, “Where you had these flows, there is nothing living there today.” 

He added, “it’s like a desert 70 km from the volcano, and yet, amazingly, just under the rim of the volcano, in places that avoided these density currents, you do find life. You find sponges. They dodged a bullet.”

An uncrewed surface vessel (USV) developed by UK-based boat manufacturers Sea Kit International was also employed in mapping the volcanic currents. Using the vessel, the researchers were able to safely monitor the ash that spread from the volcano while sitting in a room located 9,940 miles (16,000 km) from Hunga Tonga.

Why does it matter to map the impact of the Tonga eruption?

The TESMaP survey is a part of the Nippon Foundation GEBCO Seabed 2030 project, an initiative aiming to map the oceans across the globe by 2030. The researchers mapped 8,494 square miles (22,000 km2) of the area surrounding the volcano during the TESMaP project. 

The explosion and tsunami from the Tonga volcano took human lives and damaged infrastructure (such as roads, hotels, and resorts) near the beaches of various countries in the Pacific region. Findings from the TESMaP survey would help us better understand the range up to which the explosion from the volcano caused damage. 

Using the data from the survey, the authorities can accurately pinpoint the danger zones around the Tonga volcano region. This information would further let us know which areas are safe for future human activities and what disaster management strategies could be employed to mitigate the losses from any such future events.