How Are Tsunamis Predicted? (Useful Resource)

how are tsunamis predicted

Tsunamis are some of the most feared and detrimental natural forces that this planet has to offer, so it’s important that we can predict them before they arise.

But how are tsunamis predicted? Well, in this post we’re going to go through how tsunamis are predicted as well as what tools are used and how warning signals are sent.

In short, tsunamis are predicted using gauges and buoys that send signals to information centers in the region.

Let’s take a closer look…

How Are Tsunamis Actually Predicted?

Most tsunamis are caused by earthquakes on converging tectonic plate boundaries. However, tsunamis can also be caused by volcanic activity, extreme weather as well as comets, asteroids, and more.

This means we humans have to be on guard and constantly monitor such activities at all times, to help predict tsunamis and be able to evacuate surrounding towns before they happen.

But how are tsunamis predicted?

Well, tsunamis are detected by open-ocean buoys and coastal tide gauges. These gauges report changes in sea level every minute and feed it to local stations within the region.

As well as monitoring sea levels, seismograph stations are also used to record earthquake activity. A tsunami watch goes into effect if a center detects an earthquake of magnitude 7.5 or higher.

Civic defense agencies are then notified and data from tidal gauge stations are closely monitored to detect early signs of a tsunami.

If a tsunami does trigger the gauges, a tsunami warning is immediately sent to all potentially affected areas so that they can evacuate and proceed to safety.

The good news is that in today’s modern age, we have some incredible technology that is able to detect the slightest rise in sea level and give us the earliest warning possible of such an event.

For example, The Deep-Ocean Assessment and Reporting of Tsunamis (DART) uses pressure recorders that sit on the bottom of the ocean and can detect the slightest of change in overlaying water pressure.

The DART system can detect a tsunami as small as a centimeter high above sea level, pretty impressive, right?

NASA, the space giant is also heavily involved in detecting tsunamis before they occur.

In 2010, researchers at NASA’s Jet Propulsion Laboratory successfully demonstrated elements of a prototype tsunami detection system.

The system successfully predicted the size of a tsunami following the Feb 27th, 2010, Chilean Earthquake.

In the future, this system may be able to be incredibly helpful in detecting the early signs of a tsunami before it happens, giving us more effective advanced warning signals.

With such devastating events as tsunamis, hurricanes, and large storms, it’s important for us to have the tools and technology, alongside the expert personnel to detect them early in advance.

What Tools Are Used To Predict A Tsunami?

There is a combination of different tools that are used to predict a tsunami, and oftentimes they all work together in order to give us the most up-to-date and accurate information to predict the event.


A seismograph is usually the first tool that is used in order to predict a tsunami.

This is because this tool is used to predict earthquakes, and if a large earthquake happens then there is a likely chance of a tsunami being close behind.

The seismograph network used by NOAA and other agencies is used to triangulate the latitude and longitude of the source of the disturbance.

As the seismograph waves travel much faster through the crust of the earth than they do through the water, this tool gives an early first warning of a potential tsunami.

Ocean Buoys

The first direct measurement of a tsunami comes from ocean buoys that float on the surface of the ocean.

NOAA and its counterpart agencies use these buoys, alongside a pressure monitor that goes down into the ocean floor to detect even the slightest changes in pressure.

The pressure monitor is incredibly sensitive and allows NOAA to be able to detect pressure corresponding to a millimeter of increased wave height.

Tidal Gauge

Tidal gauges are used to record the high and low tide heights at a specific location and bind that information to a set of GPS coordinates.

Unlike ocean buoys, tidal gauges will detect tsunamis only, but they won’t give as much warning. This is why the buoys are used first but the data has to be filtered, as it could be many things that trigger it.

Tidal gauges detect underwater landslides at their specific location, which gives the reader an accurate location of where the event is happening.

Satellite Altimetry

Satellites have been shown to be incredibly helpful in detecting tsunamis by being able to measure and detect the size of a wave.

The information learned from the event in 2010 has spawned new research into using satellites to measure ocean distortions.

In the future, we could see an increase in using satellites to detect tsunamis, as the likes of NASA are constantly improving their accuracy and technologies.

How Are Tsunamis Warning Signals Sent?

Once the tsunami has been detected from the above methods, the information is then used to forecast tsunami arrival times and impact.

The models help warning centers to update or cancel warnings as they learn more about the earthquake that results in the tsunami.

In the United States, warnings are sent to Coastal National Weather Service offices and emergency and local management officials.

From there, multiple lines of communication such as the Emergency Alert System, as well as Sirens and Mobile Phone Alerts are used to warn and encourage people to evacuate in the surrounding areas.

State geological surveys and the US geological survey (USGS) help to conduct research to determine where tsunamis have occurred in the past and where high-risk areas are located.

Can Tsunamis Be Prevented?

Sadly, once a tsunami has formed and is in motion, there is no way to stop it.

There is new research coming out that suggests a tsunami may be able to be stopped in its tracks by using sound waves, but this is inconclusive and yet to be tested.

When a tsunami is in motion, the best we can do is use early warning systems to detect the tsunami and give people in the surrounding areas enough time to evacuate the area.

Damage control is the main method that is used to reduce the impact of a tsunami, ensuring that people are out of harm’s way.

This is a force of nature that cannot be reckoned with, so it’s vital we have the latest, up-to-date technology to detect them as early as possible.

Final Thoughts

So, how are tsunamis predicted? Multiple devices and tools look for early signs such as earthquakes, rising sea levels, and tremors in the ocean.

As the years go on and technology advances, we are getting better and better at detecting tsunamis before they happen, meaning lives can be saved and damage can be limited.

However, there is still no current known method to prevent a tsunami.

Thanks for taking the time to read this post and I hope you’ve learned a thing or two about tsunamis today.

If you have enjoyed this post, feel free to stick around and learn more about tsunamis and other extreme weather phenomena.

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