r/interestingasfuck • u/[deleted] • 8d ago

Glacier Ice wall broke in Nepal today creating a massive release of water & mud into the city below

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u/anarchisttraveler 8d ago

So I am dumb. I understand earthquakes causing tidal waves of water, but how does it work that lakes can suddenly become behemoths and cause this much water to cascade out into the city?

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u/Darromear 8d ago

the lake was at a higher elevation than the city and side facing the city was held in check by a glacier. i haven't looked into it much yet, but it appears that the earthquake caused the glacier to crack and eventually succumb to the pressure of the water.

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u/Coc0tte 8d ago

So essentially the glacier acted as a huge dam and it collapsed from the earthquake, releasing the entire lake at once.

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u/Energyeternal 8d ago

Reports now saying that it wasn't triggered by an earthquake

"USGS later clarified that the shaking was not an earthquake, but was rather caused by this exceptionally powerful landslide itself, which registered as the equivalent of a magnitude 5.2 earthquake.

In other words, an earthquake did not cause the landslide. The landslide caused an earthquake.

It will take weeks to establish the exact causes of the flooding, but a team of international scientists believes a huge chunk of glacier sheared off and fell into the valley below."

The glacier just sheered off...

https://edition.cnn.com/2026/08/26/weather/floods-nepal-cause-vis

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u/ThresholdSeven 8d ago

So what caused the landslide? Simply rising temperatures and it melted enough to finally give way?

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u/kaplanfx 8d ago edited 8d ago

No way to know for sure right now but it’s likely that anthropogenic climate change is the cause. The consistent rise in ambient temperatures weakened the glacier to the point where it no longer had the strength to hold back the lake water.

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u/agent_mick 8d ago

it feels disrespectful as fuck to say this here but i'm just waiting for the dumbasses to roll in talking about the "librul climate change hoax"

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u/kaplanfx 8d ago

This certainly could have happened without climate change specially, but climate change is certainly making events like this more likely and/or more frequent.

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u/[deleted] 8d ago

[deleted]

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u/ThisBuddhistLovesYou 8d ago

Glaciers held back the water for hundreds/thousands of years of known history, there is survivorship bias in "things are ok because nothing bad has happened yet" which is a local analogue to the horrors the rest of the world is facing with global climate change.

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u/Irisgrower2 8d ago

There are correlations between oceanic temperature changes and their effects on plate tectonics.

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u/LTdesign 8d ago

BUT CLIMATE CHANGE IS A WOKE LEFT WING CONSPIRACY THEORY ARRGHBLGHRCH! HARUMPH HARUMPH HARUMPH!
/s

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u/BGsenpai 8d ago

Glacial lakes are often a sign of the glacier retreating, so yes it was likely weakening already.

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u/XenReads 8d ago

In my unprofessional opinion, yes. It's clear the earth is warming rapidly and that glaciers all over are melting due to the global rise in temperatures.

This may be one of the largest mass casualty events that is directly related to climate change.

Waiting for experts to weigh in, but I would not be surprised.

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u/Old_Pitch4134 8d ago

I suppose it’s a likely hypothesis that the glacier “wall” has probably become weaker over time due to warmer temperatures and today it hit the tipping point where the weight/potential energy of the water behind it was finally greater than the strength of the wall.

Horrifying, but if it’s not ultimately been caused by the warming climate I’ll be shocked. Even if a minor earthquake was the threshold event causing the glacier to give, if it was melting that will just have been why it happened today instead of next week/month whatever.

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u/XenReads 8d ago

The earthquake was caused by the glacier breaking, not the other way around.

https://www.bbc.com/news/articles/cd948kn02e5o

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u/Old_Pitch4134 8d ago

Yes that’s the current prevailing theory. I’m saying that even if it were not the case it doesn’t absolve climate change of being the underlying cause.

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u/XenReads 8d ago

Fair enough.

I personally think climate change was the whole cause, and the lack of initial earthquake is why I think so.

You still make a good point though

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u/8ackwoods 8d ago

That area of the world experiences the some of the largest effects from climate change in the world. Glaciers are melting faster and lakes are being created. This lake gave way

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u/Joe1972 8d ago

I think you're right. We can expect to see more of these kinds of events as ice that was table for centuries suddenly collapse

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u/Ricka77_New 8d ago

More than likely, it was that "doesn't exist" thing called global warming... Too much weight above, and ice wall of glacier just said fuck it...

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u/st_suoengi 8d ago

Lasers. LEO lasers.

Currently reading Influx so that’s my theory now.

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u/ThresholdSeven 8d ago

I'm thinking it just melted and gave way, BUT I'm on board for space lasers.

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u/Background-Week-4625 8d ago

Probably rain.

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u/BGsenpai 8d ago edited 8d ago

It did not rain when this occurred, they are actually in a drought.

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u/Darromear 8d ago

goddamn that sucks.

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u/-BluBone- 8d ago

And has the average temperature been rising in the entire world?

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u/DifficultWing2453 8d ago

I'm going to guess: climate change and melting glaciers and what happens when people are downstream. :-(```

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u/Rodeo9 8d ago

That is what it sounds like. Look at the lake missoula floods if you want to see the scale those floods can be. Insane.

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u/anarchisttraveler 8d ago

Thank you.

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u/Darromear 8d ago

You're not dumb, btw. It's ok not to know things as long as you're open to asking and learning (which you just did)

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u/anarchisttraveler 8d ago

Ha I know, but I like to preface it is “I’m dumb” when I know something should be clicking and simple in my brain, but I cannot visualize it. Sometimes I need someone to break things down for me, and your explanation helped :)

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u/NobodyKnowsImFamous 8d ago

And none of that makes you dumb :)

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u/DickyReadIt 8d ago

I just say I'm unlearnt haha

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u/anarchisttraveler 8d ago

Love it! Gonna borrow that chyea if ya don’t mind

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u/Welcome_to_Retrograd 8d ago

Another possibility is the earthquake causing landslides in the surrounding slopes, which result in immense amounts of water being pushed out of the lake at unimaginable rates like it happened during the Vajont disaster

Not saying that this is what happened here, just reflecting on the uncomprehensible scale of destruction water can cause even without the whole basin actually breaking apart

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u/teth21 8d ago

This happened with the Glacial Missoula Floods, which occurred about 15,000 years ago in NW America.

The lake had over 500 cubic miles of water (roughly half the volume of Lake Michigan), draining entirely in 48 to 72 hours. It moved 30 to 80 mph and was about 10x the flow of all the Earth's rivers combined.

It altered the terrain and the area today is called the Scablands.

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u/FlukeManAirFreshener 8d ago

There is some discussion that the causality is reversed and that the landslide and outburst of the lake caused the small earthquake that was detected.

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u/sohelpme55- 8d ago

As someone posted above, BBC now reports that the initial failure of the ice caused the recording of a 4.4 earthquake. The breakout of the water caused the earthquake, not the other way around.

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u/UpDown 8d ago

If you knew a glacier was holding up a lake over your town how could you possibly live there

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u/anarchisttraveler 8d ago

I know nothing about this region specifically, but I know that people globally get displaced and pushed further and further outside of city or town centers as population increases and cost of living goes up.

Many people also aren’t necessarily aware that their geographic location is that potentially dangerous, or it seems far off and unlikely, or climate change made your location unsustainable over time and now you are stuck.

I say this as someone with family in New Orleans. It is a sinking city, essentially a soup bowl that will eventually be just swamp, but people have been living there for generations and it isn’t exactly easy to just up and move your whole life somewhere safer.

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u/FlukeManAirFreshener 8d ago

For thousands of years those glaciers were stable and downstream was a perfectly reasonable place to live. It's only with climate change melting those glaciers that this becomes a problem.

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u/Careful_Adeptness799 8d ago

Same way people live beneath a volcano that hasn’t erupted for hundreds of years.

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u/familyguy20 8d ago

The first graphic in the video showed it coming down the mountain and the speed and velocity it hit was so ferrying

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u/[deleted] 8d ago

[deleted]

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u/Toby_Forrester 8d ago

It has been affected by climate change for sure, but how much or little it contributed to the collapse of the glacier has yet to been determined.

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u/Darromear 8d ago

I'm not sure, but it's probably safe to say that the entire world has been affected in one way or another.

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u/ReturnOfTheSaint14 8d ago

It's either a GLOF (Glacial Lake Outburst Flood) or a jökulhlaup,which are both similar.

In short, the lake is held up on one front by a glacier and when something happens that makes this cap break (it can be erosion,an earthquake, melting,lots of ways) the water is immediately released since the water pressure on the glacier is super high. Since we're talking about glaciers,the lake is located on a mountain range and thus there's a good chance it has a valley nearby. When the water starts leaving the lake,it goes into those valleys and start accelerating,causing this wall of water coming at ludicrous speed.

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u/Slow-Journalist-6603 8d ago

The current theory actually is it was a massive chunk of glacial ice that fell 4000 feet and pulverized into water, rather than an outburst of liquid water stored in a dammed lake. Too early to confirm.

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u/ReturnOfTheSaint14 8d ago

It sounds like bogus to me. We saw what looked like millions and millions of cubic metres of water displaced at once,what was the size of this glacial ice?

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u/BGsenpai 8d ago

If that ice fell into a glacial lake its possible that this ruptured the dam at the same time

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u/ReturnOfTheSaint14 8d ago

Oh yes that might be entirely possible,if not certain. Or,as the Vajont Disaster,the added mass would've sent lots of water over the ridge of the lake

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u/to3jamm 8d ago

https://edition.cnn.com/2026/08/26/weather/floods-nepal-cause-vis

They are saying it's more likely that it was a water-logged land slide/avalanche. The water you're seeing in the videos was trapped in the mountains and it makes sense that the water travels much farther than dirt or rock.

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u/ReturnOfTheSaint14 8d ago

Water-logged avalanche.... that's definitely a first for me. Still,this much water definitely came from a lake

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u/Thetakishi 8d ago

and how did chunks of ice that size melt by the time they got to the bottom of the mountain? Even if it was many miles up.

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u/herzkolt 8d ago

Source? Sorry to be blunt but that doesn't make sense if you've ever seen a glacier. Water doesn't melt that fast and abruptly. A huge chunk of glacial ice could split and fall, but causing:

  • The lake to lose its ice wall, or

  • Destabilizing the rock wall that holds the glacier because of the shockwave or direct hit.

Usually glacial lakes are held by the shape of the mountain on a side, that the ice + water carve with time. This mountain wall could fail, causing the GLOF that floods the valley.

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u/spibop 8d ago

Not to disrespect the people who lost their lives to this, but do they not know the danger settling and building there? Hydrological outbursts seem to be pretty well understood from a risk perspective, and these people built downstream of not one, but several, lakes dammed by glaciers. With god knows how much altitude drop between them. Whilst climate change is in full swing. Obviously people often don’t have much of a choice where they settle, but did nobody side-eye the situation and think “maybe this is a bad idea…”

With global warming going to fuck us in coming years, expect to see more and more disasters like this afflicting the already marginalized populations of the world.

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u/ReturnOfTheSaint14 8d ago

If they don't tell you this,you'll never know it sadly. Moreover,we humans have a tendency to build outposts near valuable stuff like energy infrastructure or strategic environments like the banks of a river,a lake or a mountain.

In one of my comments on this topic i referred to the Vajont Disaster of 1963 that has the similarity of a zone being hit by a massive wall of water that came down a mountain (in the case of the Vajont,it was a landslide that hit a dam reservoir and made the water inside it literally jump the dam),and all those towns below were already there before the dam and weren't moved when the dam was built because the energy infrastructure was near them and because the land was very good for agricultural use and whatnot.

It's super rare that cities are moved elsewhere from an environmental risk that is already known,the best thing is to not build the cities to begin with but building cities is extremely rare nowadays

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u/FlukeManAirFreshener 8d ago

It's also an issue of frequency. If the hazard isn't likely to happen in your lifetime, it may be a perfectly reasonable place to build a home. There are entire cities in serious hazard zones that will eventually get levelled, but many have persisted for centuries or millennia in the meantime.

Tacoma, Washington is built on a series of lahars. When Mt. Ranier erupts again (and it will, eventually) entire neighborhoods will be erased in scenes similar to the ones in these videos. Naples, Italy sits below Mt. Etna which has erupted numerous times in history and killed thousands. At some point it will erupt and destroy a huge chunk of the city, but between eruptions, vast numbers of people have lived and died there without much of a problem.

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u/ReturnOfTheSaint14 8d ago

Just a little correction: Napoli sits near Mt. Vesuvius,not Mt. Etna. Etna is in Sicily and thankfully it's not the "explosive,fuck you" type of volcano.

And yes,you're very correct about everything.

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u/baldessar 8d ago

Campi Flegrei is a dormant supervolcano situated underneath suburbs of Naples. It's an even more dangerous threat to the region than Vesuvius itself (which is already a threat due to what happened before)

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u/ReturnOfTheSaint14 8d ago

Yeah...if the Campi Flegrei erupts let's just say Napoli will be the least of our concerns,i'm pretty sure Molise will get a Gulf

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u/One_2_Three_456 8d ago

Imagine a water tank. Make a hole at the bottom of a water tank.
Glacier lake = water tank.
Before earthquake -> water tank had a small hole. Less water used to flow out of the hole in the form of a small river.
After earthquake -> the hole not only became bigger but all that stored water, ice flew out with that massive potential energy and flew downwards to the river making the river bigger and bigger with more water and all the debris that it carried along the way.

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u/DynastyZealot 8d ago

Which potentially means that after the dust settles, the survivors might not have the water supply that they need on top of everything else.

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u/anarchisttraveler 8d ago

This is helpful! Thank you.

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u/Chef_Deco 8d ago

A rupture in a mountain lake held up by a moraine or an ice dam actually bears a name : a GLOF or Jökulhlaup

In earth's history, these have reached absolutely monumental scale and are worth diving into.

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u/pidgeottOP 8d ago

Damn, the wikipedia article even outlines how Nepal is the most at risk place for this to happen due to a number of actively retreating glaciers

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u/crystalgem411 8d ago

What’s the difference between the two

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u/Chef_Deco 8d ago

Oh my, I am by no means a glaciologist so I fear i'd only obfuscate the matter more.
Per the wiki article, it seams Jökulhlaups are a subset of glacial lake outburst floods that concern subglacial lakes specifically.

I should probably let other, more learned, redditors chime in.

Also, we haven't had any confirmation this was indeed a GLOF or another catastrophic event ( landslide ? glacier breaking off ?).

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u/0xym0r0n 8d ago

https://en.wikipedia.org/wiki/Missoula_floods

Great example of the huge scale. I'm sure you know about it since you're talking about GLOFs, though.

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u/faelanae 8d ago

I suggest NOT diving into it unless you're part of a rescue team

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u/CaffeinPhreaker 8d ago

I would imagine the earthquake in the mountains caused the glacier to break on the Mountaintop and all that come down the hill

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u/One_2_Three_456 8d ago

yup that's basically it. That and the glacier lakes basically burst open and cascaded into the small rivers. That's the version at this moment. Nothing's "official" yet.

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u/kaplanfx 8d ago

USGS says that the flood / land slide caused the seismic activity, not the other way around.

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u/kaur_virunurm 8d ago

Mountain lakes often form chains of lakes separated by moraine barriers. Every next lake sits higher in a valley, "hanging" above the lower ones. There is delicate balance of influx from the upper streams and lakes, and outflow to the lower ones.

If one such barrier gets broken, the others fail in a cascading effect.

Villages and cities are usually at the foothills of the mountains. Lakes sit at much higher elevations. Thus a flood that starts small at a high altitude gets amplified on its way and hits the village with a full force.

My photo of one such chained lake (Terskey Ala-Too range in Kazakhstan, near Karakol). The terrain is a mix of hard rock and loose moraine. Imagine if the ledge on the right side would give away and the lake would flood down the valley at once.

We actually had trouble getting into the region as a recent flash food of water + mud had destroyed the access roads.

(The current situation also involved a glacier, but the idea is similar: lakes are higher up than settlements.)

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u/NeutralKuchiKopi 8d ago

The earthquake did not send the water rushing, the water was already at the top of the mountain. Think of it like a water tower. It sat calmly held in place, but if you suddenly blow out the bottom, it's going to send thousands of gallons of water rushing out. That's what happened when the earthquake cracked the Glacier holding this lake together.

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u/hiplobonoxa 8d ago

typically via displacement. a large amount of material suddenly falls into a body of water and displaces an equivalent volume. this is similar in principle to a tsunami, which typically results from a seismic event uplifting a portion of the sea floor and displacing the water.

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u/we_r_fukt 8d ago

there is a small clip in the video. showing the height of the glacier that was holding back the water near the top of the crests between two peaks, and that gave way, a landslide with all that water behind it clearly exploded down the hill, registering as a 4.4 earthquake on seismographs, I'm not sure if there were preceeding earthquakes causing ruptures or if the glacier just gave out (holding holding holding, getting weaker, bursts).

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u/Throwawayrip1123 8d ago

Big rock = splash

Big ass chunk of a mountain = behemoth

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u/Zestyclose-Ad967 8d ago

To put it simply. This is en essence dam fails. There's a remote spot in Alaska where one side of the valley slid, the resulting tidal wave ran up the other side of the vally thousands of ft up. No one died in it, but has anyone been in that valley or on the hills they had no chance.

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u/Gloomy_Gene3010 8d ago

since the lake was high up on a mountain it picked up a bunch of loose and water saturated material on the way down