Mumbai, June 7: Have you ever wondered if a wave could shake the Earth without a tsunami or earthquake? In September 2023, seismic stations across the globe picked up mysterious tremors repeating every 90 seconds for nine straight days. The signals were eventually traced to Dickson Fjord in East Greenland, where no eyewitnesses, not even a nearby military vessel, reported anything unusual. Now, a study published in Nature Communications has confirmed the culprit: not a traditional tsunami, but a rare phenomenon known as a seiche.

Unlike typical tsunamis that travel across oceans, seiches create rhythmic oscillations confined within a body of water, generating seismic pulses felt far beyond their origin. As per the study, the breakthrough came through satellite data from NASA’s SWOT mission, which captured these standing waves in motion. This marked the first time scientists could visually confirm the phenomenon in progress. Let’s know what exactly a seiche is and how it quietly shook the Earth from a remote Arctic fjord in 2023. ‘Greenland Is Ours’: Prime Minister Mute Egede Says Island Isn’t for Sale As Donald Trump Seeks Control ‘One Way or Other’.

What Is Seiche?

A seiche is a standing wave that forms in an enclosed or partially enclosed body of water, like a lake, bay, or fjord, when it is disturbed by external forces such as landslides, strong winds, or seismic activity. Unlike a tsunami, which travels as a single massive wave across the ocean, a seiche causes water to slosh back and forth repeatedly, much like water swaying in a bathtub. This motion can persist for hours or even days, depending on the size of the water body and the intensity of the disturbance. Seiches can generate strong currents, localised flooding, and even seismic signals detectable far from their origin. Donald Trump Jr Arrives in Greenland After His Father Said US Should Own Danish Territory (Watch Video).

How the 2023 Seiche Happened in Dickson Fjord

In 2023, the seiche in Dickson Fjord, East Greenland, was triggered by two massive landslides caused by melting glaciers. As the Arctic warmed, the glaciers became unstable, causing huge amounts of rock and ice to tumble violently into the fjord. This sudden displacement of water created giant waves, essentially a megatsunami, that had nowhere to escape due to the narrow, enclosed shape of the fjord. Instead of dissipating, the water sloshed back and forth, generating a standing wave that lasted for days.

These movements or seiches caused the water level in the fjord to rise and fall by up to two meters repeatedly. The continuous motion produced low-frequency seismic signals detected worldwide, puzzling scientists for months. Unlike typical tsunamis, which move outward as a single wave, the seiche’s rhythmic back-and-forth movement acted like a giant natural oscillator. Thanks to advanced satellite data and seismic analysis, researchers confirmed this unusual event, linking it directly to climate change–induced glacier melt and landslides in the Arctic.

(The above story first appeared on LatestLY on Jun 07, 2025 12:38 PM IST. For more news and updates on politics, world, sports, entertainment and lifestyle, log on to our website latestly.com).