Himalayan Cataclysmic Flood Has Nepal and Tibet Reeling: Will Climate Change Make This Type Of Disaster More Common?

The tragic aftermath of the epic Nepal flood last week.
We're not 100 percent sure yet whether climate change
was a contributing factor to this calamity. However
scientists say a warming world increases the odds
something like this will happen again in Nepal,
or anywhere else with tall mountains and glaciers.

 You've probably seen those horrific images by now of that impossibly enormous flash flood that blasted down a Nepalese river valley this week. 

The news on the aftermath keeps getting more and more tragic and horrifying. 

As of early Sunday, the death toll from the wild flood stood at 794, according to the BBC. Another 2,502 people are missing. 

The flood occurred on the Nepal-Tibet border, but many foreigners were in the disaster zone. India reports 320 missing people. China has nearly 100 nationals missing. Ninety people from the United States are also missing. So are dozens of people from Ukraine, Malaysia, Australia, the UK and other countries. 

There were some bright spots of survival. A school headmaster made a snap decision to evacuate 900 students in the building after hearing reports something was wrong upstream. He also got word to another 800 students who were on the way to school to stay uphill and away from the school.

All the students ran up a hill and survived. The headmaster said that had he waited another 10 minutes, himself and all the students would have died. He could have made another decision. The school was a fair distance above the river and normally would not have been threatened by floods. This time was different. 

The Nepalese calamity was shocking, beyond tragic, and scary as hell. And something like this could happen again as climate change warms the planet and thaws ice and permafrost on tall mountains around the world. 

WHAT HAPPENED

We don't yet know whether climate change had a hand in causing the tragedy in Nepal. It could have been a freak occurrence. More research on the disaster needs to be completed before we can draw firm conclusions. A full understanding of what happened will take months. 

Here's what we at least think we know so far: 

 As the Washington Post reported:

"High-resolution images taken by satellite monitoring company Planet Labs show the site of the apparent landslide high in the Himalayas, close to the Nepal-China border." (Editor's note: China claims Tibet, but Tibetan exiles dispute that. The China in that quote is actually Tibet). ....."In the 'before' image a glacier can be seen looming some 4,000 feet above a narrow valley, emptying into the meandering Lhende River.

Afterward, the glacier appears smaller by about 2 million square feet - equal to the area of about 25 professional soccer fields. The valley is strewn with ice and mud. And the river is swollen beyond its banks, submerging the surrounding vegetation beneath murky brown floodwater."

When the glacier and rocks collapsed into the valley, seismographs detected it. At first geologist thought there had been an earthquake measuring 5.2 on he Richter scale, but the vibrations detected were the actual glacial collapse, not an earthquake.

Friction of the rocks and avalanche debris as it fell 1200 meters (nearly 4,000 feet) melted some of the ice. By the time the whole thing reached the valley it was a slurry, like wet cement. The New York Times was able to obtain and verify a video of huge chunks of ice falling from the Langtang Lirung mountain and crashing to the valley floor below. 

The debris briefly blocked the river on the valley floor and water piled up behind all those rocks and ice. But this wasn't a classic glacial lake outburst. 

Those outbursts are caused by meltwater trapped behind glacial ice. It finally breaks through, and a rush of water flows downstream. 

This was much worse. Water behind that enormous pile of unstable debris finally collapsed it, and the huge volume of slurry raced downstream. As it roared downstream, the mass of water and debris absorbed more trees, rocks and other debris, making the onrushing tidal wave larger and more powerful.

Nobody in the valley below knew what was about to hit them. It hadn't rained much in the days prior to the huge flood. It was rather sunny and nice that day. For many, the first warning was the roar of the onrushing debris, mud and water. It was too late to escape. 

CLIMATE CHANGE?

As I mentioned above, we don't yet know if climate change had anything to do with the calamity in Nepal. 

However, those rising temperatures across the globe thaws permafrost in high cold mountains.  That permafrost is sometimes the "glue" that holds rock and ice together atop steep mountain slopes. Melt the permafrost and everything falls apart. 

Scientists are saying that fact makes disasters like this one more likely in the coming years. Not only in Himalayan mountains, but any high mountain range in the world with glaciers clinging to their upper slopes. 

As the Washington Post notes, we have seen several glacial collapse disasters in recent years, either through the actual collapse or the floods they often cause. Glacial collapses buried a village in Switzerland in May, 2025. 

Another smaller glacial collapse killed 11 hikers in Italy back in 2022. Another glacial collapse triggered floods in 2021 that swept away at least 200 people in India. 

Investigators want more information on exactly what happened in that Himalayan mountain valley. And in the rocks and glacier above. 

The fear is this type of thing will happen more frequently. "Glaciers are going to shrink and melt. Permafrost....will be warming and weakening and degrading over time. You'll get landslides and debris flows.....You take all that together and you can say climate change is going to have a destabilizing effect on these high mountain regions," said Simon Cook, a University of Dundee glaciologist, who is part of a team reviewing satellite images that show where the disaster began. 

The planet's tectonics might have worked in concert with climate change to cause the calamity. 

The glacier involved in the disaster is way up high on a Himalayan mountain called Langtang Lirung,  with an elevation of 23,734 feet. At least right now. 

Langtang Lirung, like the rest of the Himalayas are slowly rising due to the collision of tectonic plates dating back tens of millions of years. The Himalayan mountains continue to grow in elevation at roughly the rate of 0.3 inches per year.  Over millennia, that's thousands of feet. 

Glaciers have been on these mountains for millennia, too. As the mountains grow taller, they ever so slowly get steeper. Over thousands of years, the steep slopes become too much for the glaciers, and pieces of them break off.

Now, with the permafrost melting, making the rocks and the ice become more and more unglued, the chances of those steep slope glacier collapses happening prematurely have increased exponentially.  

Early warning systems in the region where this disaster happened weren't great. Let's hope governments upgrade these systems in Nepal, and near other risky mountains, including some in the United States. 

Videos:

The giant, sudden flood overwhelms and destroys a hydroelectric dam that was under construction. Click on this link to view,  or if you see the image below, click on that. 

This one has been all over social media, but it's still incredible dramatic and scary. A family is trapped on the upper floors of a house amid the raging torrent of the Nepal flood. Somehow the house remained standing and the family survived. Click on this link to view, or if you see the image below, click on that. 

This is a good video with several clips that give you an idea of the breadth and power of the extreme Nepal deluge. Click on this link to view, or if you see the image below, click on that.