How Underwater Volcano Eruption caused a Tsunami Warning in the Pacific Ocean

On Saturday, January 15, an underwater volcano erupted near Tonga and was likely the biggest underwater eruption recorded on our planet in more than 30 years. The eruption caused Tsunami waves across the Pacific Ocean that reached the western coast of the US.

The eruption was captured from space in real time as a huge cloud of ash, gas, and steam spewed 12.5 miles (!!) into the atmosphere!

Satellite images from JMA show the volcano eruption in Tonga on January 15.

Can you say "Hunga-Tonga-Hunga-Ha'apai"?

Tonga is a south pacific kingdom made out of more than 170 islands. About100,000 people call it home.

Hunga-Tonga-Hunga-Ha'apai is one of Tonga's islands, and it is a volcanic island.

The volcano itself is an underwater volcano that reaches sea level in 2009 after a volcanic eruption. It lies between two islands: Hunga Tonga and Hunga Haʻapai.

Above from left to right - Tonga's location, Tonga and the underwater volcano, Hunga Tonga-Hunga Haʻapai island

What is an Underwater Volcano?

Underwater Volcanoes or Submarine Volcanoes are underwater vents in the Earth's surface from which magma can erupt. Most underwater volcanoes are very deep but some exist in shallow water and can send material into the atmosphere during an eruption.

Above - Hunga Tonga eruption early on 15 January 2022, taken from the GOES-17 geostationary weather satellite positioned above the equator at 137.2°W longitude.

What is a Tsunami

A Tsunami is a Japanese word that means "harbor wave." It is one of nature's forces.

It is a large wave caused by movements in Earth's outer layer, or crust, which move ocean water. A Tsunami can speed across the ocean as fast as a jet plane. An earthquake, or a volcano eruption in the ocean, can cause a Tsunami.

If a volcano erupts in the ocean, the lava flowing out of the volcano takes up the space of the water around it. That water has to move and it can turn into a large wave. The bigger the volcanic eruption, the bigger the wave of water would be. When the wave reaches the shore, it grows taller because the ocean is shallower.

How do we know if a Tsunami is on its way?

After an oceanic earthquake or underwater volcanic eruption, a Tsunami warning is issued.

NASA has a tool called MISR (the Multi-angle Imaging SpectroRadiometer) that watches for Tsunamis from space. MISR can see sunlight reflecting off waves and measure their height.

Above: The MISR instrument on the Terra satellite takes pictures from different angles to look for tsunamis. Credit: NASA/JPL/Shigeru Suzuki and Eric M. De Jong, Solar System Visualization Project

So what Happened after the Hunga-Tonga-Hunga-Ha'apai eruption?

The eruption caused a Tsunami on Tonga's largest island, Tongatapu, with 4 feet high waves that flooded large areas.

Tsunami warnings went into effect across many Pacific Islands, parts of New Zealand, and as far as Japan, Peru and the United States' + Canada's pacific coast.

The eruption sent waves to the US West Coast, with some exceeding 3 and 4 feet in height, according to the National Weather Service. Tsunami waves were felt in California, Alaska and Hawaii.

Above - A tsunami has hit Tonga's largest island, Tongatapu.

Vocabulary

Underwater Volcano - volcanoes which are under the surface of the world's oceans

Tsunami - a large ocean wave usually caused by an underwater earthquake or a volcanic explosion

Tornadoes

This weekend our hearts broke when we heard about the devastating string of powerful tornadoes that struck the U.S. Midwest, killed many people and caused so much damage.

What are tornadoes? How do they form? Why are they dangerous? And what does football have to do with it?

The Art in Science - News for curious kids will answer some of these questions.

So what is a tornado?

A tornado is a type of storm with very powerful rotating winds. A tornado, also called twister or cyclone, is a violent rotating column of air extending between the Earth’s surface and the base of a thunderstorm. A tornado wind speed can reach up to 300 miles/hour. A tornado can make a lot of damage : destroy building, uproot trees, make cars fly up in the air and more.

How does a tornado form?

The formation of a tornado is so complex, scientists have yet to understand it.

Tornadoes start during a thunderstorm. Not all thunderstorms will create a tornado. Most tornadoes start from a supercell. A supercell is a strong kind of rotating thunderstorm (called a mesocyclone). Supercells create the deadliest tornadoes. read more HERE.

Touchdown

To be called a tornado the funnel cloud has to touch the ground, otherwise they’re called a funnel.

Can we prepare for a tornado?

Meteorologist can not yet predict when and where a tornado will start but the NOAA Storm Prediction Center watch the weather 24 hours a day 7 days a week (meaning ALL the time). If a tornado is bring reported by spotters or by a radar a TORNADO WARNING will be issued. This means that if you are in that area you should ACT NOW.

What should you do?

• Shelter - Move to a small room away from windows on the lowest floor like a basement

• Cover your body

• Follow the news for updates

Did you know?

• The winds of a tornado are the strongest on earth.

• Although tornadoes can happen anywhere on earth, the US has the most tornadoes every year (over 1,000 every year - WOW!!).

• The most famous ones can be found in Tornado Alley which stretches from Texas to the Dakotas in the US.

• Most tornadoes last less than 10 minutes

Vocabulary

• Tornado - a violent rotating column of air extending from a thunderstorm to the ground.

• Supercell - a strong type of thunderstorm with rotating strong winds

• Storm - violent weather with heavy rain adn wind. Thunderstorms, tornadoes, and hurricanes are types of storms.

• Thunderstorm - a storm with lightning and thunder

• Meteorologists - a scientist that studies the atmosphere to predict and understand earth's weather

• Atmosphere - the layer of gas that surrounds Earth