A gigantic tsunami six times the height of India’s Qutub Minar crashed into a remote Alaskan fjord in 2025, but surprisingly, almost no one witnessed it in real time.
Scientists have now reconstructed the event in surprising detail, revealing that the 481-meter-high “mega tsunami” was one of the largest ever recorded on Earth. The height of the Qutub Minar in New Delhi is 72.5 meters.
The massive wave hit Tracy Arm Fjord in southeast Alaska on August 10, 2025, after a colossal landslide sent more than 64 million cubic meters of rock into the glacier’s narrow entrance.
The impact displaced enormous amounts of water almost instantly, unleashing a huge wave that crossed the fjord at speeds exceeding 250 kilometers per hour.
Researchers say the tsunami reached a maximum height of 481 meters (1,578 feet), making it the second highest tsunami ever documented after the famous Lituya Bay megatsunami in Alaska in 1958.
What makes the event extraordinary is that almost no one saw it happen.
The tsunami occurred around 5:30 a.m. local time in a remote fjord frequented primarily by cruise ships and kayakers. Because it occurred before the tour boats entered the area, no deaths or injuries were reported. Scientists later described it as a near-miss disaster that could have become catastrophic if it had occurred just hours later.
So how did scientists detect a tsunami that no one heard or saw?
According to the study published in the journal Science, researchers reconstructed the event using satellite images, aerial surveys, seismic records and computer simulations.
The landslide itself generated long-period seismic waves powerful enough to be detected around the world. Scientists said the seismic signal was equivalent to a magnitude 5.4 earthquake.
Even more unusual was what happened next. The tsunami created a seiche, a standing wave trapped within the fjord that caused water to slosh back and forth for more than 24 hours. This generated a persistent seismic vibration with a rate of approximately 66 seconds that continued globally for up to 36 hours.
Satellite images later revealed huge scars along the fjord walls, where the towering wave had destroyed forests and vegetation.
Researchers linked the landslide to glacier retreat driven by climate change. As the South Sawyer Glacier melted and retreated rapidly, it destabilized the steep mountainside above the fjord, eventually causing it to collapse.
Scientists warn that these climate-related megatsunamis could become more common in glacial regions as rising temperatures continue to reshape fragile mountain landscapes.
– Finish