Landslide, tsunami, seiche in Tracy Arm fjord, Alaska - 10 August 2025

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SUMMARY

On August 10, 2025, a significant landslide occurred on the eastern side of Tracy Arm fjord, Alaska, generating a megatsunami that reached heights of over 1,000 feet. This event, while primarily affecting the fjord, produced a seiche that sloshed across a 1,100-meter stretch of water for nearly 35 hours. The tsunami was the largest caused by a landslide in the past decade, as reported by the Alaska Earthquake Center. It is important to note that the 1,000-foot measurement refers to the run-up on the fjord's sides, not the sustained height of the wave.

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On August 10, 2025, there was a massive landslide on the eastern side of Tracy Arm fjord. Although some sources mention 1000 ft tsunami, that height represents the run-up on the sides of the fjord. Technically it was a seiche.

n August 10th, a more than 1,000 foot high megatsunami was generated 59 miles southeast of the city of Juneau within Alaska. While the worst of this wave was completely confined to the Tracy Arm (fjord), evidence shows that the seiche from this landslide generated megatsunami continued sloshing back and forth across a 1,100 meter stretch of water for nearly 35 hours. Do note that this did not cause 1,000 feet or more of run-up for this entire 35 hour long duration.




Early View of Tracy Arm Landslide Features​




Tsunami-causing slide was largest in decade, earthquake center finds​

https://www.gi.alaska.edu/news/tsunami-causing-slide-was-largest-decade-earthquake-center-finds


https://alaskapublic.org/news/envir...tsunami-rip-through-tracy-arm-south-of-juneau
 
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Wow. You have a knack for finding these, huh? Good thing young people with climate-angst aren’t following you. They’d have a nervous breakdown!

In my youth is was The Bomb. For todays youth it’s The Climate.
 
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sbrothy said:
Wow. You have a knack for finding these, huh? Good thing young people with climate-angst aren’t following you. They’d have a nervous breakdown!

In my youth is was The Bomb. For todays youth it’s The Climate.
And getting under a desk is just as helpful for both.
 
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ShadowKraz said:
And getting under a desk is just as helpful for both.
Hah yeah: "Duck and cover!" :woot:
 
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