In the hours after the Tonga volcano erupted, unprecedentedly powerful winds and unusual electrical currents sprang up at the edge of space.

To say that Tonga’s eruption last January was explosive is almost an understatement. The eruption caused, among other things, an enormous shock wave, which even reached the Netherlands. In addition, huge ash plumes and tsunamis arose and part of the island sank. That’s not even all, new research shows. For the effects of the eruption have even been felt in space.

eruption

On January 15, a submarine volcano near the island nation of Tonga in the Pacific Ocean erupted violently. The eruption of the Hunga Tonga-Hunga Ha’apai volcano has gone down in history as the largest volcanic eruption of the past thirty years. And that is not for nothing. As mentioned, the underwater explosion propelled a gigantic ash plume, 300 miles (480 km) wide, reaching nearly 40 miles (40 km) high. The eruption even sank most of the island, which had been above the waves since 2015. In addition, dangerous tsunamis were created that injured and killed people thousands of miles away along the coasts of the Americas. Even 10,000 miles away in Alaska, pops and rumblings were heard hours after the eruption.

ionosphere

However, this is not all. Because researchers have discovered that the eruption of the Tonga volcano has caused a stir even in space. The team analyzed data from two satellites orbiting the Earth. And it shows that in the hours after the eruption, strong winds and unusual electric currents were created in the ionosphere – the upper part of our atmosphere located at the edge of space.

The atmosphere
Our earth’s atmosphere is made up of four layers, namely the troposphere, stratosphere, mesosphere and the ionosphere. The troposphere is the lowest layer of the atmosphere and contains about 80 percent of the total mass of air. Most meteorological phenomena occur in this part of the atmosphere. Above the troposphere we find the stratosphere. This is where the ozone layer is located, which protects life on Earth from ultraviolet sunlight. Then, at an altitude of 50 kilometers, the mesosphere begins. The temperature in the mesosphere decreases to around -100 degrees Celsius at an altitude of about 80 kilometers. In the mesosphere, among other things, the noctilucent clouds occur. Finally, the atmosphere has the ionosphere. This is the layer around the earth where the particles are ionized by radiation from the sun.

The massive volcanic eruption caused major pressure disturbances in the atmosphere, leading to extremely strong winds. These managed to penetrate ever higher atmospheric layers. And the higher these winds came, the harder they blew. As these powerful winds reached the ionosphere and even tapped the edge of space, unprecedented wind speeds of 725 kilometers per hour were clocked.

Electric currents

In the ionosphere, these extreme winds also influenced electric currents. Particles in the ionosphere regularly form an eastward flowing electric current – ​​the so-called equatorial electrojet. It is powered by winds in the lower atmosphere. After the Tonga volcano erupted, the equatorial electrojet changed direction dramatically, flowing west for a short time. “It’s very surprising that the electrojet was reversed by something happening on the Earth’s surface,” said study researcher Joanne Wu. “This is something we’ve only seen before in strong geomagnetic storms.”

The eruption of Tonga Volcano had many far-reaching consequences, as depicted in this illustration. The effects were felt even down to space. Image: NASA’s Goddard Space Flight Center/Mary Pat Hrybyk-Keith

The results of the study, published in the journal Geophysical Research Letters, thus offer a surprising look at how events on Earth extend even as far as space. The study therefore contributes to scientists’ understanding of how the ionosphere may be affected.

“The volcano created one of the largest space disturbances we’ve seen in modern times,” said study researcher Brian Harding. “It allows us to better understand the poorly understood connection between the lower atmosphere and outer space.”