It was such a smart move. It isn't beating you over the head with "plant more trees cause tree good" it showed you the science behind a topic and then showed how those principles are being ignored for others gain
That was wild. I've seen some flooding videos, but it was mostly water and some cars, but to see whole houses being moved like a paper boat in a river is another level. I can imagine losing everything like that 🤯
I've seen a lot of disaster footage. Forest fires, floods, tornadoes, hurricanes, etc... but something about seeing the landslides, with the houses just being swept away through the mountain, really hit me. The tumbling house at 14:27 was particularly disturbing and made me gasp out loud in real life. I'm not sure why this hits me more than any of the other devastation I've seen, but it really just irks me on a primal level.
2:35 to 2:40 is the best show of the amount of rainfall here. You can see a hole in the water at his feet from the umbrella. Never seen anything like that before and it looks crazy.
I always wondered why they didn't run that test in a circle, than they could have more control over how long their dumby "ran" , could have more control over speed and time.
In Denmark we're currently experiencing the results of a man made earth slide, where tons of toxic earth started shifting after heavy rains. Threatening to bury the town of Ølst under 5 meters of earth. The reason? A company was permitted to build a mountain of contaminated earth on top of a special type of clay that becomes slippery like soap when wet. (Not sure if it's the same as "quick clay") - But a country with no mountains having a legitimate and dangerous earth slide is wild.
Brazil had something similar some years ago, a company built a dam to storage mining waste and it broke due to the lack of maintenance, leading to a landslide of toxic mud that destroyed a city and contaminated a whole river with heavy metals.
How true: When a Dane talks about a company being permitted to "build a mountain" of something, he really means business, relatively, in a country where the highest "mountain" is less that 150m high! Capitalism has to be taken with a grain of salt and strictly monitored - which was not the case with the Danish man-made "mountains", with predictable results.
When we moved to Japan we recieved this nice pamphlet from the city, listing all the potential natural disasters (eartquake, tsunami, heavy rain, tyfoons, landslide, flooding, and fire) and what to do in case they happened. Including a list of all emergency supplies you were expected to have for your household, easily accessible in a rucksacks ready for a fast evacuation at any moment. Not sure wether to be terrified or reassured!😅
Definitely be terrified. All that preparation can only minimize, not prevent, loss of life and property. Look at the recent Noto earthquake, for example. Japan leads the world in earthquake preparedness, but there were still hundreds of deaths, and thousands left homeless after the earthquake.
@@stevenqirkle Resilience is more important than prevention. Asking a total protection from disasters and bad lucks are a religion, not a science. Science is how human has progressed this far against all the odds, and is how Japan is led and going the right direction. By science.
I'm not sure where you were from, but I can tell you here in the US there's none of that unless you've got a friendly neighbor. I moved from California where rolling brown-outs were a common thing in summer (high dry heat and too much AC usage) and unless you grew up there you wouldn't know to have plenty of water and sun screen available to Pennsylvania where we'd get occasional crazy summer thunderstorms, not to mention learning to be prepared for snow and ice on the roads. If it weren't for family I'd have known none of it, so I'd say it would be really reassuring to get something from the city/state saying "Hey, be prepared with these minimums just in case"
@@jnfunvufb who’s asking for total protection? I’m just saying the dangers from natural disasters in Japan are real. Magnitude 7.5 earthquake in 2024 in Noto, 6.6M in Hokkaido in 2018, 7.0M in Kumamoto in 2016, and of course the 9.1M Tohoku earthquake in 2011 that killed 20,000 people that the country still hasn’t fully recovered from. And there was the 2019 Typhoon that did $17B in damage and killed 118. Or the 2018 floods that killed 225 and did $10B. And these are just recent events. The fact is, if you live in Japan long enough, you will experience a devastating natural disaster. The original post was asking if they should be terrified or reassured. I think it’s commendable how well Japan prepares for and responds to disasters - better than anyone else in the world. But there is a good reason they take them so seriously. And anyone living in Japan should have a healthy amount of fear and respect for earthquakes, typhoons, winter storms, volcanoes, landslides, etc.
I spent a week in Yakushima several years ago and remember being surprised at how much it rained there. It rained even more than in my hometown which is prone to hurricanes. Now it makes sense why.
read the god damn comment you shuman🐑 he said "I spent a week in Yakushima several years" a common trait for a lie-switching the plot of it mid-story@k4vinzen
This is truly a marvel of modern science. The work being done at this Japanese facility is indispensable for disaster management and research. It's fascinating how much we can learn from simulating extreme weather conditions. Kudos to the dedicated scientists working tirelessly to keep people safe.
12:40 WOW!!! BEAUTIFUL TIME LAPSE. I like how you showed that a natural and gradual change like the bends in a river weren't even forming in comparison to how quickly the forests got leveled and developed upon.
Holt was the most precipitation recorded in 1 hour (305mm - 12in), but the most violent ever recorded occurred in 1970 in Guadeloupe, France. 38mm - 1.5in of precipitation were recorded in 1 minute. That's a 2280mm/h or 90in/h pace.
@@cralix2782 what happened to france in the 70s?? and why would god do that?? *cough* *cough* *ignore the flood cause there is no actual evidence beyond bible for that *cough*
Shlatt visited France in the 70s, coincidence, I think not, but seriously what was happening in France in the 70s (This is a dumb joke for a dumb reference btw)
Great to see this channel flourish! Welcome back to Australia, Derek! As someone who grew up in Watsons Bay, I immediately recognised where this shot ( 2:04 )was made from 😊.
My respect for Japan has increased 1000 folds the way their scientists and government are trying to save their citizens 🙇♂️ This video and the earthquake one prove the effort they put into saving lives of their citizens. ❤
Being from the UK rain was never more than a mild inconvenience for me until one day which started nice and sunny, my girlfriend and i were in a park having a picnic when all of a sudden the weather turned and immediately began a downpour unlike i've ever seen, the rain was so heavy and cold that we could barely breathe and we were now on a completely waterlogged field with lightning striking around us. The rain was also so heavy that we could not see 20ft in front of us so we lost track of where we were going and ended up far off track from the building we were heading towards for safety. It was terrifying, ever since then i have never underestimated how dangerous rain can really be when it gets heavy.
Harrowing story friend. Have had a similar thing happen while driving. Everyone had to stop, pull over and simply let it pass. It was cool to see without any direct communication with each other, everyone just stop what they were doing because doing anything would be too dangerous.
You’re the FREAKING GOAT for putting that little wheel on your built in sponsor for your video I always skip these and I always go to far or not far enough. That was perfect! Hahaha
If I had a nickel for every time Veritasium made a video about a large scale indoor natural disaster simulator in Japan, I would have two nickels, which isn't a lot but it's weird that it happened twice (edit: for some reason I forgot part of the meme lol)
SLIPPERY VS FRICTION The soil particles aren't more slippery, they just aren't being pushed together as hard. It's like applying an upward force to a couch in order to make it slide more easily, the floor and couch aren't more slippery, but there is less friction.
thank you for this, i was slightly confused by the explanation provided in the video. i'm also figuring that someone could make a model of this phenomenon by making sand castles.
@@maxp3141 Yes. I find it easier to understand using an example that is more relatable to humans on the macroscopic scale. There is less friction, but none of the parts have become more slippery.
Originally, the rainiest place on Earth is Maysynram, India. Located in Meghalaya's East Khasi Hills district, Mawsynram is celebrated as the wettest place on Earth, receiving so much rain that its average annual rainfall reaches a staggering 11,871 millimeters. As an Indian, I can assure you that the place is really beautiful. It's worth unraveling, it's beyond just rain.
10:28 "Water doesn't make soil slipperier" ..."but water decreases the friction causing a slide" What now? For me "decreasing friction" is the definition for making something more slippery.
Maybe this example will help, if I have a super grippy tire and I want to reduce friction I can either: 1) Swap to a harder compound (less "grippy") tire which will reduce friction, without lubrication 2) Keep the same tire but add oil to lubricate, here I have reduced friction again but this time with lubrication
What they meant is that water doesn't lubricate the grains in the soil allowing it to slip. Water changes the state of the soil, from liquid to plastic to semi-solid and solid. Water "invades" the pores between grains, putting pressure on those grains from all directions. There are coarse grained soils like sand and gravel and fine grained soils like clay and silt. The latter trap water because their porosity is low, meaning the gaps between grains are smaller. When that happens, water can't escape and as previously mentioned applies pressure on the soil grains. That makes the soil a) heavier and b) as previously mentioned increases the pressure applied on the grains inside the pores. a) and b) decrease a characteristic of the soil called "shear strength" which is basically a factor determining how easy it fails. All that means that enough water and you get a soil that was previously solid suddenly behaving like a liquid.
10:15 That scientist's statement about the "myth" of water making the ground slipperier sounds like semantics as the following explanation details how water decreases the friction of the minerals that in turn leads to the landslide.
Friction is the resultant force Slipperiness is about the coefficient of friction Friction force is the pressure force times the coefficient. So it is not the coefficient that decreases but the force exerted that is reduced due to the water applying an opposing pressure force. Edit: not my own insight. Someone a few comments below said this and i think he is right
It makes it slip easier...which means it makes it slipperier in my opinion. I'm sure the stuff with the coefficient of friction is true but I'd say the water makes it slipperier.
The water makes it so that there is less friction FORCE. The minerals don't get slippier, as in that the coeff. of friction does not decrease. (I just said what @outandabout259 said in another comment)
This facility makes every kind of rain there is. Little bit of stinging rain, big ol fat rain, rain that comes in sideways, and even rain that seems to come straight up from underneath.
Typhoons aren't _like_ hurricanes. They _are_ hurricanes, because the only difference between hurricanes and typhoons is geography: if a tropical cyclone of sufficient strength is north of the equator and over the Atlantic, it's a hurricane, if it's north of the equator over the Pacific (there are specific longitudes involved) it's a typhoon, and if it's south of the equator it's a tropical cyclone. That's literally the only distinction.
Right. All hurricanes and typhoons are tropical cyclones. 'Hurricane' and 'typhoon' are just labels we decided - arbitrarily, as far as I can tell - to give to strong tropical cyclones that occur in particular parts of the world.
@@JonMartinYXD It's all cultural. Hundreds of years ago, before meeting, the Europeans said 'hurricane' while the Japanese said 'typhoon'. Then the scientists looked at all of them and said 'tropical cyclone'.
They are all the same thing, but they do spin counter rotating in opposite hemispheres, which is proof of a spinning globe, flat earthers generally don't have an excuse for.
We had another massive quick clay incident a couple years back too where a lot of people were killed. In Gjerdrum. Not sure if it qualified as landslide though
The most rainfall ever recorded within one hour was actually 402mm which occured on the 3rd of July 1975 at Shangdi, Nei Monggol, China. The 305mm record at Holt occured over the course of 42minutes (equivalent to a 435mm/hr intensity). However, the most intense rainfall recorded occurred in 1970 at Barot, Guadeloupe where 38mm was recorded within a 1-minute duration (equivalent to 2280mm/hr intensity).
While reading what you wrote, I remembered a rain I once experienced, in Bulgaria (I used to live there for a few years, a few decades ago). It only lasted like 3-4 minutes, but it was so incredibly intense, that while driving on a local highway, I had to literally stop in the middle of the road, because my wipers (on highest setting) couldn't cope at all, making visibility in front of the car literally none. A dead stop, in the middle of a highway, where just minutes ago, cars where travelling at 120+ km/h. I bet they all stopped and just sat there, just like I did. The sound of the water hitting my car was almost deafening, loudest I've ever heard. I mean that was just an absolute mayhem. No idea what mm/h that was though.
I have seen Rainfall here in the tropics that would easily beat one meter per hour, but it's usually a couple minutes worth, which still floods places. Damn does it hurt as well.
Great to see this channel flourish! Welcome back to Australia, Derek! As someone who grew up in Watsons Bay, I immediately recognised where this shot ( 2:04 )was made from .
The landslide footage shown was insane. I had to rewind and rewatch those clips a few times to even wrap my brain around what was happening. Especially the one where an entire house just.. falls off the cliff.
1:39 this is literally 69% of the rainfall intensity recorded in Holt. Not sure how one can claim “this warehouse can simulate the most intense rainfall anyone has ever experienced.”
Love the Japan-series! There are alot of influencers exploring Japan right now, but you are exploring engineering and science topics and I apreciate that
That was pretty cool, I'm glad Japan is serious about managing their natural risks. The whole landslide and flood thing was the topic of an exam of mine back in university (I topped the class on this one). Indeed, vegetation is the primary and simplest and cheapest way to keep a slope stable. Level a forest on a slope right above a town that a river is crossing but channeled by concrete, put buildings all over the original bed of the river, IN A PLACE WHERE IT REGULARLY RAINS LIKE CRAZY after dry summers....... and you get people in big trouble almost each fall.
Quote at 10:27: "Water doesn't make the soil slippier....It decreases the friction between grains." Um, isn't decreasing friction by definition, making it slippier?😂😂😂
Dose holding a rubber above a piece of paper and moveing it makes the rubber slipperier? The water making distance between the soil grains not making the surface slipperier.
I immediately come to think of a heave rainfall I experienced last year. I was at a folkmusic festival in Sweden, Delsbostämman. It had already rained a fair bit, but when I went in to my tent to go to sleep little did I know I would wake up to 84,2mm of rain. Many of my friends had their tents destroyed that night, but somehow my managed to survive. Another memorable rainfall to mention was the 160+ mm rainfall over the town of Gävle in 2021. Over one night more than double the amount of downfall that normaly falls during one entire month came in just one night. It left many households destroyed and parts of the town flooded. You'd think Gävle wanted to stop at the snowchaos...
The logic at 10:45 does not settle with me right. The fact that the pores pressure is increasing due to the presence of water is making it sound like the pore is expanding pushing the sediment all around it. Instead I believe this phenomena to be caused by 3 primary motives: 1. The water adds weight on to the dry soil below it. 2. The buoyant force is essentially making all the sediment have a lower weight (which a. removes some normal force lessening the frictional force vertically and b. lessens the effect of gravity wanting to level it out) 3. Since rain is fairly pure; I also wonder how on a larger scale the effects of the water dissolving the sediments comes in to play (shrinking/dissolving sediment geometry is like pulling out more jenga pieces, and water generally becomes more dense as it dissolves more dense material ie salt water)
I have a problem with your logic. At 10:16 you have the "Geologist Expert" that says rain does not make the soil slippery. Then you follow that up with "water pressure increases and reduces the friction between the grains of soil." Kinda sounds like the same thing to me.
water doesn't decrease the coefficient of friction between soil particles (= make it more slippery), it decreases the force the particles apply to each other and, by doing so, decreases friction force without making the soil more slippery. To give an analog, if you apply an upward force to a couch to make sliding it along the floor easier, does that make the floor more slippery? No, it doesn't, but it still decreases the friction.
Yeah, bro can't keep his story straight, either it doesn't make things more slippery or it decreases friction but you can't have it both ways. Slip and loss of friction are one and the same.
But it does make the interface between the couch and the floor more slippery, if it wouldn't, lifting the couch wouldn't make you able to push it any more than before. Increase in normal force increases friction, look at brakes. Also the cambridge dictionary sais: "If something is slippery, it is wet or smooth so that it slides easily or causes something to slide" @@outandabout259
I really appreciate how you used all SI units. I was born and bred in USA, but I use mostly SI units. I quote most measurements in SI, and translate if they ask. We don't need a government edict, if more people use SI, the others will get it eventually. I might be slow on temperature, but I am enjoying a nice 10 C.
As a Japanese from where it’s literally illegal to use units other than SI, I can’t imagine converting units back and forth. That’s wasting so much brain resources unnecessarily. I wish the human race stick to the SI system once and for all.
at 10:15 he says water doesn't make it slippery, but then says water gets into the pours and makes it loose friction? isn't losing friction effectively slippery?
Japan never cease to impress me. So many natural disasters and yet they're still doing so well. I can't imagine if these events happens in Europe, the continent will be wiped out, we do not have their skills to endure these natural events.
I think you greatly underestimate the amount of world class engineers in Europe. The EU has loads of environmental prevention systems, just look at the Netherlands.
I want to share a thing about rainfall that I learned some time ago which was quite surprising. When I was younger and hearing about rainfall, I tended to hear two measurements: milimeters and litres per square meter. I always considered the latter to make more sense for me and I didn't put much more thought to it. Then, one day I thought to simplify the units of l/(m^2) to see what I get. A litre is a decimeter cubed which is 1/1000 of a cube meter. This gives us 1/1000 * m^3/m^2. The result is 1/1000 of a meter, which... is a milimeter! Surprise!
This will blow your mind: The meaning of 1 mm water is, that if you put a container with straight walls into the rain, it will fill with a height of 1mm no matter how big it is. The bigger it is, the more water will fall into it,but also its area is bigger,and thus after all the rise in water level is the same. And if you have a square meter sized container, filled to 1mm height,it will contain 1l of water. So the units are literally the same
Quality title. Way more interesting than if you were actually just talking about the location that gets the most rain. Walking the line between clickbait (for clicks) and honest title (for transparency) is tricky, but you really nail it.
@jonaswox you cannot have your run of the mill pump for what is shown in the video. And probably not only one given the uniformity of the rain throughout the warehouse
I've never been in a hurricane, but the monsoon rains in Eastern Arizona are the most intense, and painful rain I've ever been in. The raindrops felt like marbles hitting you. It only took a couple minutes to be flooding our town. That guy running out into the rain simulator looked just like the rain in Eastern Arizona.
All Vertasium videos have been absolute bangers recently. For the past 6 months each and every video has been added into my personal reserarch-notes-for-worldbuilding playlists. They educate us on so much about the world and about people
I studied a little about rain and landslide in Environmental Science course in my BBA study more than a decade ago. Good to see it again in this video. This keeps reminding me the importance of preserving the natural environment and the damage we have done to our home planet.
In 2018, A state in India named Kerala, experienced a greatest flood, due to the amount of rain and the sudden opening of the dams. Also, since some of the places were surrounded by mountains, landslides of greater intensity happened, causing the loss of countless lives. If, a facility like this is built here to study the rainfall disasters and prevent it in the future, it will be a huge benefit for the people living in Kerala.
This video is the exact representation of why I love watching Veritasium, They show us what we as humans have done, what we are doing & what should be do to prevent worst outcomes. The technical, physical & other aspects really binds it together. The main things humans should do is to plant more trees & reduce our wastage. I think all other problems can be sorted out if we can complete this one.
*Really* intense rainfall never lasts anywhere near an hour. When it's really coming down hard, it's like standing under a waterfall (MUCH heavier than anything shown in this video; under those conditions, you wouldn't be able to see a man standing as far away, as he was from the camera), but it never keeps that up for more than a couple of minutes at most. 30 seconds is more typical. But in that 30-120 seconds, you can get several inches of rain. I've seen this happen three or four times in my life.
It makes the soil act as if it were more slippery and, in fact, can even become 'liquified' and move more like a liquid than a solid, say, a thick paste, but it's definitely not what you want foundations on. Just reducing the friction of a solid doesn't normally make that solid turn into a liquid, that's why the distinction is important.
The thing with science is that you need to be accurate, not just say « well it acts as if it makes it slippery so it makes it slippery » that’s a shortcut you’re not allowed to make Something « slippery » has a low coefficient of friction. The water doesn’t lower the soil’s coefficient of friction. So no, it’s not more slippery. There’s just less force applied
@@books2438 "Slippery" does not have scientific definition. It is just relative term for perceived low friction. And water actually do lower soil's coefficient of friction (even when shear modulus is much more important in this topic). Google scientific publications about it or just walk on bare soil when it's raining. It is slippery.
As a child I promptly remember experiencing a rate of rain that was impossible to see through with even the wiper blades on full speed. I remember it as if the windshield was an ocean with waves and if that’s not the worst amount of rain I couldn’t imagine what they experienced
@@GreenLightFlight yeah I was really young like probably 2 or 3 but my mom definitely had to stop driving but I didn’t really understand what was happening but it left a memorial impact on me that I remember over 20 years later , I remember the rain and couldn’t imagine what someone who has experienced worse went through
I don't think this rain warehouse can match the intensity of nature. It's only when averaged over an hour that it claims that prize I think. Nature can be much more intense in short bursts like a minute or two. I've also experienced the unbelievably intense downpour that brings traffic to a standstill because nobody can see the road in front of them.
I have never been more captivated by a channel I never knew existed. I love this content. Reminds me of SmarterEveryDay. Fantastic videos! Great information. Very well done!
I always thought that the wet soil is much heavier than dry, hence the gravity pull is stronger, so at a tipping point it overcomes the friction and starts a landslide.
Don't know how that well this applies here, but friction is calculated with the normal force, aswell as the friction coefficient. As the increading weight linearly increases the normal force and the force trying to start the landslide, it shouldn't affect things too much. (that assumes that every part of the slope is the same angle. But obviusly if you have a part of the slope that only holds because of the flatter slope above and below it, adding more weight will make it more likely to slide.
Ok, so I (over?)thought about it and I think what Derek & co were trying to say is that we falsely assume that when water falls on quartz, probably iron, and other particles that make up dirt, they become one. What actually happens is that it just fills in space between those particles. 'Absorb' is not what we intuitively think it is, to put it another way. The mass of water might cause an effect due to gravity, but it's much less than the loss of friction.
@@NoahBuehler I think you're right. I forgot that the force of friction is directly proportional to the normal force. I think the reason why I and OP ignored that is because the ground is at a slope, so the normal force vector would be at an angle, while the gravitational force vector is straight down. I'm too lazy to do any calculations though
I am not sure what the definition of heaviest rainfall is used to get the rain at Holt at 1:51 but Nobby in Queensland, Australia had 203mm in 20 minutes in 1939. That's 50% heavier than the Holt rain. It also equates to about 600mm/hr which is double the rain rate in the "rainiest place on earth". I've been on the receiving end of short bursts of 1-2mm/minute rain and I can't imagine what 5-10mm/minute would be like.
So this video just got recommended to me and the algorithm is scary, not only am I currently under an evac alert for possible flooding, but i live in Pemberton where the landslides over the road photos are taken at 12:32
2:08 304.8mm in 42 minutes is 435.4mm/hr. If the facility can only manage 300mm/hr then it can only simulate 69% of “the most intense rainfall anyone has ever experienced”.
It only rained for 42 minutes and then stopped. That's an average of 304.8mm over the somewhat arbitrary one hour period. It would have been 435.4mm/hr only if it had actually continued to rain for that time, but it did not. You cannot simply extrapolate to an hour, because that is not the situation that occurred. An amount of rain bigger than those 304.8mm has not actually been observed over a period of one hour.
@@redlopa1 So if you cut yourself, lose 5ml of blood in a second before you stop the bleeding, then in your opinion that means that it's reasonable to say that you just lost 18 liters of blood per hour? As a general rule, if we're talking about extremes, it is never reasonable to extrapolate "x per y" to a y that's bigger than the y that actually occurred.
The hardest rainfall I've ever seen was in Denver Colorado in 1998. One of our workers came in to work absolutely soaking wet. Like just stepped out of the shower soaking wet. I asked if she couldn't get dropped off by our front door that was only +- 15 feet from the dropoff area and she said she had. I opened the front door and was shocked to see an almost solid looking wall of water with visibility of less than 50 ft but almost no wind!! I had to quickly shut the door as the water instantly started coming in. It only lasted about 10 minutes but we had over a foot of water in a well drained parkung lot!! I still shake my head whenever I think of it! The biggest raindrops... Miami Florida, Sept/Oct of 1976. 1 raindrop would spread across 30% + of my dad's front windshield. Good thing it was barely coming down, which is why I could see how big the drops were due to the very low clouds. Thanks for reading my memories.
We love this! We appreciate the feature of our amazing wind tunnel technology and the STEM that goes into indoor skydiving! We have a passion for teaching students the physics of flight and we’re so glad we could help make learning more fun, the way you do! ❤
12:41 "Humans are REALLY GOOD at causing landslides, and we're shaping the land a heck of a lot more quickly than geologic processes do" sums it up so well.
That guy saying water doesn't make things slipperier is just being pedantic. By preventing contact that provides greater friction, it does, in fact, make things slipperier.
He is not even pedantic. Otherwise, he would be able to see the contradiction. He probably just likes to oppose popular opinions. He is not like OtHeRs
6:15 I have talked with Norway geologist engineer and scientist I have in my family. The reason is a clay, but it is the reaction for perforating thin earth surface by basements of buildings leaving water to penetrate deeper layers, under the clay, so the clay gets extremely slippery. Developers buildings are often built cheaply without any care about future, they are not secured against water penetration around them. A biiig problem in Norway.
Your claim is misleading. There's a huge difference between "the most rain in an hour" and "the most rain ever experienced". I've seen rain considerably worse here in Tucson but for 5 to 10 minutes. It was hitting the ground so hard it was splashing up to my eye level and I couldn't see more than 20 feet.
Dose holding a rubber above a piece of paper and moveing it makes the rubber slipperier? The water making distance between the soil grains not making the surface slipperier.
The Batagaika Crater in Siberia is a good example of how deforestation can cause landslides. It almost a kilometer wide and looks pretty cool on satellite view on Google Maps.
The cut from "trees are incredibly effective at preventing landslides" to the saw and deforestation was 10/10. Great editing!
It was such a smart move. It isn't beating you over the head with "plant more trees cause tree good" it showed you the science behind a topic and then showed how those principles are being ignored for others gain
Yeah, it was heartbreaking to see. Sends a far more powerful message than saying it repeatedly.
I'm ngl I giggled, it was pretty cheesy
but in the end the conclusion was landslides come from the use of fossil fuels, what a sham
@Repent-and-believe-in-Jesus k
The fact the entire warehouse can move and reconnect to a its water supply is incredible.
If you want incredible, then look up how they move spacecraft to the launch pad at Cape Canaveral.
yeah like 2m/h is really incredible...@@Shinkajo
There's houses like this.
@@Jayess-cnot just houses. Whole commercial buildings were moved at some point at least in US and China
@@rinkashikachi I thought they meant just like rotate it. There's a house that rotates and constantly disconnects and reconnects itself to its pipes
The footage of all those houses being destroyed in seconds is so scary. The screams from that man gave me chills.
That was wild. I've seen some flooding videos, but it was mostly water and some cars, but to see whole houses being moved like a paper boat in a river is another level. I can imagine losing everything like that 🤯
Watch "Himachal pradesh india flood and landslide last year" you'll be shocked😢
You should know that it's by design. Easy and cheap to build new houses, only to be ruined by a new storm later on
@@bobby4tw these things happen because of deforestation. The trees roots normally hold the ground together.
I've seen a lot of disaster footage. Forest fires, floods, tornadoes, hurricanes, etc... but something about seeing the landslides, with the houses just being swept away through the mountain, really hit me. The tumbling house at 14:27 was particularly disturbing and made me gasp out loud in real life. I'm not sure why this hits me more than any of the other devastation I've seen, but it really just irks me on a primal level.
don’t forget all the kaiju attacks they experience
They probably have a facility to simulate that
Bring out the Jägers😂
@@oni7729nope, we’re gonna need ultraman for this one
Noone ever thinks about the kaijus. They have feelings to you know lmfao
2:35 to 2:40 is the best show of the amount of rainfall here. You can see a hole in the water at his feet from the umbrella. Never seen anything like that before and it looks crazy.
🤓
2:30 Small update: the heavy rainfalls with dozens of casualties in Spain were at 343 mm. This video is LESS bad than that was
Mythbusters needed this place when testing walking vs running in the rain :D
My thoughts exactly 😂
important moment in human history
Minute physics did a great short video on that topic. Worth a watch
Well, I mean since it's pretty simple math not rly, but would be fun content tho!
I always wondered why they didn't run that test in a circle, than they could have more control over how long their dumby "ran" , could have more control over speed and time.
In Denmark we're currently experiencing the results of a man made earth slide, where tons of toxic earth started shifting after heavy rains. Threatening to bury the town of Ølst under 5 meters of earth. The reason? A company was permitted to build a mountain of contaminated earth on top of a special type of clay that becomes slippery like soap when wet. (Not sure if it's the same as "quick clay") - But a country with no mountains having a legitimate and dangerous earth slide is wild.
Capitalism goes brrr
Shifting where? Was it the tallest garbage pile in the whole country?
I'm from Denmark and I'm glad I left lol. Theyve made it extremely difficult for people of color to move there. Theyre extremely racist
Brazil had something similar some years ago, a company built a dam to storage mining waste and it broke due to the lack of maintenance, leading to a landslide of toxic mud that destroyed a city and contaminated a whole river with heavy metals.
How true: When a Dane talks about a company being permitted to "build a mountain" of something, he really means business, relatively, in a country where the highest "mountain" is less that 150m high! Capitalism has to be taken with a grain of salt and strictly monitored - which was not the case with the Danish man-made "mountains", with predictable results.
at 12:36 the person who took that photo was literally my 5th grade teacher. i remember he told us about the huge landslide almost 7 years ago now. wow
When we moved to Japan we recieved this nice pamphlet from the city, listing all the potential natural disasters (eartquake, tsunami, heavy rain, tyfoons, landslide, flooding, and fire) and what to do in case they happened. Including a list of all emergency supplies you were expected to have for your household, easily accessible in a rucksacks ready for a fast evacuation at any moment. Not sure wether to be terrified or reassured!😅
Definitely reassured, if its japan, then the safety precautions are not lacking in any means
Definitely be terrified. All that preparation can only minimize, not prevent, loss of life and property. Look at the recent Noto earthquake, for example. Japan leads the world in earthquake preparedness, but there were still hundreds of deaths, and thousands left homeless after the earthquake.
@@stevenqirkle Resilience is more important than prevention. Asking a total protection from disasters and bad lucks are a religion, not a science. Science is how human has progressed this far against all the odds, and is how Japan is led and going the right direction. By science.
I'm not sure where you were from, but I can tell you here in the US there's none of that unless you've got a friendly neighbor. I moved from California where rolling brown-outs were a common thing in summer (high dry heat and too much AC usage) and unless you grew up there you wouldn't know to have plenty of water and sun screen available to Pennsylvania where we'd get occasional crazy summer thunderstorms, not to mention learning to be prepared for snow and ice on the roads. If it weren't for family I'd have known none of it, so I'd say it would be really reassuring to get something from the city/state saying "Hey, be prepared with these minimums just in case"
@@jnfunvufb who’s asking for total protection? I’m just saying the dangers from natural disasters in Japan are real. Magnitude 7.5 earthquake in 2024 in Noto, 6.6M in Hokkaido in 2018, 7.0M in Kumamoto in 2016, and of course the 9.1M Tohoku earthquake in 2011 that killed 20,000 people that the country still hasn’t fully recovered from.
And there was the 2019 Typhoon that did $17B in damage and killed 118. Or the 2018 floods that killed 225 and did $10B.
And these are just recent events. The fact is, if you live in Japan long enough, you will experience a devastating natural disaster. The original post was asking if they should be terrified or reassured. I think it’s commendable how well Japan prepares for and responds to disasters - better than anyone else in the world. But there is a good reason they take them so seriously. And anyone living in Japan should have a healthy amount of fear and respect for earthquakes, typhoons, winter storms, volcanoes, landslides, etc.
I spent a week in Yakushima several years ago and remember being surprised at how much it rained there. It rained even more than in my hometown which is prone to hurricanes. Now it makes sense why.
a) its fake and you switched the story mid writing
b)youre just bad at wrting in english
@@ydrib6086 if you are responding to me, your comment makes no sense
@@ydrib6086 ???
"i spent a week in yakushima several years"
did you spend a week of several years you liar🧢@@macroxela
read the god damn comment you shuman🐑
he said "I spent a week in Yakushima several years"
a common trait for a lie-switching the plot of it mid-story@k4vinzen
This is truly a marvel of modern science. The work being done at this Japanese facility is indispensable for disaster management and research. It's fascinating how much we can learn from simulating extreme weather conditions. Kudos to the dedicated scientists working tirelessly to keep people safe.
Hi
12:40 WOW!!! BEAUTIFUL TIME LAPSE. I like how you showed that a natural and gradual change like the bends in a river weren't even forming in comparison to how quickly the forests got leveled and developed upon.
The rain doesn’t make the ground slippery, it just decreases the friction between grains. Soooo it makes it slippery?
Holt was the most precipitation recorded in 1 hour (305mm - 12in), but the most violent ever recorded occurred in 1970 in Guadeloupe, France. 38mm - 1.5in of precipitation were recorded in 1 minute. That's a 2280mm/h or 90in/h pace.
man thats like swimming underwater
Bro sounds like God was trying to waterboard them for some reason what was happening in France in the 70s
@@cralix2782 what happened to france in the 70s?? and why would god do that??
*cough* *cough* *ignore the flood cause there is no actual evidence beyond bible for that *cough*
@@cralix2782 Gay sex
Shlatt visited France in the 70s, coincidence, I think not, but seriously what was happening in France in the 70s (This is a dumb joke for a dumb reference btw)
This video goes great with Practical Engineering video "Do Droughts make Floods Worse" where he goes into how soil absorption affects flooding.
Great to see this channel flourish!
Welcome back to Australia, Derek!
As someone who grew up in Watsons Bay, I immediately recognised where this shot ( 2:04 )was made from 😊.
My respect for Japan has increased 1000 folds the way their scientists and government are trying to save their citizens 🙇♂️ This video and the earthquake one prove the effort they put into saving lives of their citizens. ❤
now the amount that i want to go there has decreased by 1000 folds.
@@emilymayer5926 go away, Nazi
Opposite for me @@vVearon
@@emilymayer5926anti immigration goober try not to bringup their wrong bigoted ideas challenge (impossible)
Unit 731
Cyber homelessness
Nanking
Colonization
Being from the UK rain was never more than a mild inconvenience for me until one day which started nice and sunny, my girlfriend and i were in a park having a picnic when all of a sudden the weather turned and immediately began a downpour unlike i've ever seen, the rain was so heavy and cold that we could barely breathe and we were now on a completely waterlogged field with lightning striking around us. The rain was also so heavy that we could not see 20ft in front of us so we lost track of where we were going and ended up far off track from the building we were heading towards for safety. It was terrifying, ever since then i have never underestimated how dangerous rain can really be when it gets heavy.
Harrowing story friend. Have had a similar thing happen while driving. Everyone had to stop, pull over and simply let it pass. It was cool to see without any direct communication with each other, everyone just stop what they were doing because doing anything would be too dangerous.
This is every afternoon in tropical cities!
Use metric, don't be silly.
@@Shijaru64Just be bilingual with your measurements. It is easy to learn both.
Bro like 95 percent of people use metric @@andrewbstevens
You’re the FREAKING GOAT for putting that little wheel on your built in sponsor for your video I always skip these and I always go to far or not far enough. That was perfect! Hahaha
If I had a nickel for every time Veritasium made a video about a large scale indoor natural disaster simulator in Japan, I would have two nickels, which isn't a lot but it's weird that it happened twice
(edit: for some reason I forgot part of the meme lol)
…and a lot of counterfeit Apache helicopters 🤣🌈🤣
Always upvote Phineas and Ferb
i don’t want to be that guy, but you definitely forgot a line there
You had one task and failed it
oh hi katakana
SLIPPERY VS FRICTION
The soil particles aren't more slippery, they just aren't being pushed together as hard. It's like applying an upward force to a couch in order to make it slide more easily, the floor and couch aren't more slippery, but there is less friction.
thank you for this, i was slightly confused by the explanation provided in the video. i'm also figuring that someone could make a model of this phenomenon by making sand castles.
Isn’t that just slightly higher scale definition of friction?
@@maxp3141 Yes. I find it easier to understand using an example that is more relatable to humans on the macroscopic scale.
There is less friction, but none of the parts have become more slippery.
@@durdleduc8520 You're welcome. I didn't understand it at first either, but I figured I must be missing something, so I went searching for the answer.
I feel like your explanation still runs into the same issue. "slide more easily" means it is "more slippery"
Originally, the rainiest place on Earth is Maysynram, India. Located in Meghalaya's East Khasi Hills district, Mawsynram is celebrated as the wettest place on Earth, receiving so much rain that its average annual rainfall reaches a staggering 11,871 millimeters.
As an Indian, I can assure you that the place is really beautiful. It's worth unraveling, it's beyond just rain.
Yes
That's what I'm also thinking, the title of this video is a bit misleading.
It recieves most rainfall. But not the highest rainfall received in a short time
@@Adamonroe1 even then, the title of highest rainfall in 24 hours goes to a place in the Indian ocean
10:28 "Water doesn't make soil slipperier" ..."but water decreases the friction causing a slide"
What now? For me "decreasing friction" is the definition for making something more slippery.
slippery has a different definition in Geology. Geoligists are very technical in definitions
think of sand castles, u need damp sands. The context of slippery here refers to the built up of pore water pressure.
@@peepeetrain8755 it would have been a good idea to define those terms then... otherwise the confusion is inevitable...
Maybe this example will help, if I have a super grippy tire and I want to reduce friction I can either:
1) Swap to a harder compound (less "grippy") tire which will reduce friction, without lubrication
2) Keep the same tire but add oil to lubricate, here I have reduced friction again but this time with lubrication
What they meant is that water doesn't lubricate the grains in the soil allowing it to slip. Water changes the state of the soil, from liquid to plastic to semi-solid and solid.
Water "invades" the pores between grains, putting pressure on those grains from all directions. There are coarse grained soils like sand and gravel and fine grained soils like clay and silt. The latter trap water because their porosity is low, meaning the gaps between grains are smaller. When that happens, water can't escape and as previously mentioned applies pressure on the soil grains. That makes the soil a) heavier and b) as previously mentioned increases the pressure applied on the grains inside the pores. a) and b) decrease a characteristic of the soil called "shear strength" which is basically a factor determining how easy it fails.
All that means that enough water and you get a soil that was previously solid suddenly behaving like a liquid.
10:15 That scientist's statement about the "myth" of water making the ground slipperier sounds like semantics as the following explanation details how water decreases the friction of the minerals that in turn leads to the landslide.
Haha, interesting point.
Friction is the resultant force
Slipperiness is about the coefficient of friction
Friction force is the pressure force times the coefficient. So it is not the coefficient that decreases but the force exerted that is reduced due to the water applying an opposing pressure force.
Edit: not my own insight. Someone a few comments below said this and i think he is right
It makes it slip easier...which means it makes it slipperier in my opinion. I'm sure the stuff with the coefficient of friction is true but I'd say the water makes it slipperier.
The water makes it so that there is less friction FORCE. The minerals don't get slippier, as in that the coeff. of friction does not decrease.
(I just said what @outandabout259 said in another comment)
@@JasperR-s9z the minerals slip past each other more easily. If that doesn’t make it slipperier than what does the word “slippery” even mean?
10:09 Water doesn't make soil more slippery, it causes it to have less friction, or as most people would say MAKES IT MORE SLIPPERY.
This facility makes every kind of rain there is. Little bit of stinging rain, big ol fat rain, rain that comes in sideways, and even rain that seems to come straight up from underneath.
Forest gump
Imagine need to simulate rain instead of experiencing one. So sad
(Before some idiots thought im serious. Im not)
Nice one
Glad I wasn't the only one to think of Forrest walking chest-deep in water during Vietnam
“Fat rain”
is that when there are very few massive drops falling from the sky?
Typhoons aren't _like_ hurricanes. They _are_ hurricanes, because the only difference between hurricanes and typhoons is geography: if a tropical cyclone of sufficient strength is north of the equator and over the Atlantic, it's a hurricane, if it's north of the equator over the Pacific (there are specific longitudes involved) it's a typhoon, and if it's south of the equator it's a tropical cyclone. That's literally the only distinction.
Right. All hurricanes and typhoons are tropical cyclones. 'Hurricane' and 'typhoon' are just labels we decided - arbitrarily, as far as I can tell - to give to strong tropical cyclones that occur in particular parts of the world.
@@JonMartinYXD It's all cultural. Hundreds of years ago, before meeting, the Europeans said 'hurricane' while the Japanese said 'typhoon'. Then the scientists looked at all of them and said 'tropical cyclone'.
@@jursamaj Not many hurricanes in Europe. The name originated in the Caribbean. Spanish explorers brought it back to Europe.
They are all the same thing, but they do spin counter rotating in opposite hemispheres, which is proof of a spinning globe, flat earthers generally don't have an excuse for.
@@rasta77-x7o False: flat earthers have an excuse for _everything._ Nonsensical excuses, but excuses nonetheless.
6:15 I live 15km away from that place, in Alta, Norway!
I remember it being on the news everywhere, and it was a big devestation for us all
We had another massive quick clay incident a couple years back too where a lot of people were killed. In Gjerdrum. Not sure if it qualified as landslide though
And look at all those trees! It's pretty clear that the slide happened pretty deep in the soil.
@@kdm_entertainment jeg husker det også! Var ikke det rett på nyåret? Var på nyhetene over alt, og hele Norge fulgte med på hva som skjedde
wr
@@kkarlsen_06 30. Desember 2020 faktisk!
The most rainfall ever recorded within one hour was actually 402mm which occured on the 3rd of July 1975 at Shangdi, Nei Monggol, China.
The 305mm record at Holt occured over the course of 42minutes (equivalent to a 435mm/hr intensity).
However, the most intense rainfall recorded occurred in 1970 at Barot, Guadeloupe where 38mm was recorded within a 1-minute duration (equivalent to 2280mm/hr intensity).
While reading what you wrote, I remembered a rain I once experienced, in Bulgaria (I used to live there for a few years, a few decades ago). It only lasted like 3-4 minutes, but it was so incredibly intense, that while driving on a local highway, I had to literally stop in the middle of the road, because my wipers (on highest setting) couldn't cope at all, making visibility in front of the car literally none. A dead stop, in the middle of a highway, where just minutes ago, cars where travelling at 120+ km/h. I bet they all stopped and just sat there, just like I did. The sound of the water hitting my car was almost deafening, loudest I've ever heard. I mean that was just an absolute mayhem. No idea what mm/h that was though.
All of which are higher than the 300mm/h that this facility can do, so it can't "simulate the most intense rain recorded".
I have seen Rainfall here in the tropics that would easily beat one meter per hour, but it's usually a couple minutes worth, which still floods places. Damn does it hurt as well.
China dates are not reliable.
@@BenPyman I think it was most intense rain in japan, any rain that the simulator simulated in japan thats very intense?
Great to see this channel flourish!
Welcome back to Australia, Derek!
As someone who grew up in Watsons Bay, I immediately recognised where this shot ( 2:04 )was made from .
The landslide footage shown was insane. I had to rewind and rewatch those clips a few times to even wrap my brain around what was happening. Especially the one where an entire house just.. falls off the cliff.
1:39 this is literally 69% of the rainfall intensity recorded in Holt.
Not sure how one can claim “this warehouse can simulate the most intense rainfall anyone has ever experienced.”
The last words were so powerful 😢❤ 14:36
Came too see someone experiencing rain indoors. left learning about landslides, typhoons, and heavy rain
12:21 truely a surprised pikachu moment
Love the Japan-series! There are alot of influencers exploring Japan right now, but you are exploring engineering and science topics and I apreciate that
Good to see veritasium swooping in to fill the niche left by Tom scott
That was pretty cool, I'm glad Japan is serious about managing their natural risks. The whole landslide and flood thing was the topic of an exam of mine back in university (I topped the class on this one). Indeed, vegetation is the primary and simplest and cheapest way to keep a slope stable. Level a forest on a slope right above a town that a river is crossing but channeled by concrete, put buildings all over the original bed of the river, IN A PLACE WHERE IT REGULARLY RAINS LIKE CRAZY after dry summers....... and you get people in big trouble almost each fall.
Quote at 10:27: "Water doesn't make the soil slippier....It decreases the friction between grains."
Um, isn't decreasing friction by definition, making it slippier?😂😂😂
10:57 So water doesn't make it slipperier, it just makes it slipperier. 🤨
May be easier to think of it as turning the ground from fairly solid into a wet slush.
Dose holding a rubber above a piece of paper and moveing it makes the rubber slipperier? The water making distance between the soil grains not making the surface slipperier.
@@Phonixem so the water makes things more likely to slip on the surface but the surface is not more slippery 🤨
@@DajesOfficial u slip on water not on the surface of things
@@Phonixem water is part of the surface of things
I immediately come to think of a heave rainfall I experienced last year. I was at a folkmusic festival in Sweden, Delsbostämman. It had already rained a fair bit, but when I went in to my tent to go to sleep little did I know I would wake up to 84,2mm of rain. Many of my friends had their tents destroyed that night, but somehow my managed to survive.
Another memorable rainfall to mention was the 160+ mm rainfall over the town of Gävle in 2021. Over one night more than double the amount of downfall that normaly falls during one entire month came in just one night. It left many households destroyed and parts of the town flooded. You'd think Gävle wanted to stop at the snowchaos...
The logic at 10:45 does not settle with me right. The fact that the pores pressure is increasing due to the presence of water is making it sound like the pore is expanding pushing the sediment all around it.
Instead I believe this phenomena to be caused by 3 primary motives:
1. The water adds weight on to the dry soil below it.
2. The buoyant force is essentially making all the sediment have a lower weight (which a. removes some normal force lessening the frictional force vertically and b. lessens the effect of gravity wanting to level it out)
3. Since rain is fairly pure; I also wonder how on a larger scale the effects of the water dissolving the sediments comes in to play (shrinking/dissolving sediment geometry is like pulling out more jenga pieces, and water generally becomes more dense as it dissolves more dense material ie salt water)
Cherapunji, in the far North East of India, receives an annual rainfall of 11.77 meters.
This
Tutunendo in Colombia its pretty close, 11,77 m annual rainfall too
@@felipesernatoro9244 That's great to know.
I thought the video was about that too lol
@@Infiniti.151 Veritasium has been making mistakes with videos twice now. Once with the Rods from Gods, now this.
4:32 that subway entrance was in suzume, great movie ! Really interesting video i'm binge watchin em right now
this is stuff you never think about but there still is and its cool as hell
I have a problem with your logic. At 10:16 you have the "Geologist Expert" that says rain does not make the soil slippery. Then you follow that up with "water pressure increases and reduces the friction between the grains of soil." Kinda sounds like the same thing to me.
water doesn't decrease the coefficient of friction between soil particles (= make it more slippery), it decreases the force the particles apply to each other and, by doing so, decreases friction force without making the soil more slippery. To give an analog, if you apply an upward force to a couch to make sliding it along the floor easier, does that make the floor more slippery? No, it doesn't, but it still decreases the friction.
Yeah, bro can't keep his story straight, either it doesn't make things more slippery or it decreases friction but you can't have it both ways.
Slip and loss of friction are one and the same.
But it does make the interface between the couch and the floor more slippery, if it wouldn't, lifting the couch wouldn't make you able to push it any more than before.
Increase in normal force increases friction, look at brakes.
Also the cambridge dictionary sais: "If something is slippery, it is wet or smooth so that it slides easily or causes something to slide" @@outandabout259
What you said really doesn't make sense.@@Soken50
@@JasperR-s9z It does, I'm sorry you struggle with reading comprehension.
Switching to the producer really made this feel like a discovery channel show
I really appreciate how you used all SI units. I was born and bred in USA, but I use mostly SI units. I quote most measurements in SI, and translate if they ask. We don't need a government edict, if more people use SI, the others will get it eventually. I might be slow on temperature, but I am enjoying a nice 10 C.
As a Japanese from where it’s literally illegal to use units other than SI, I can’t imagine converting units back and forth. That’s wasting so much brain resources unnecessarily. I wish the human race stick to the SI system once and for all.
Glad my country was one of the first to adopt the SI.
i mean i can use both. most Americans can, we just dont realize it.
26th July 2005 rains of Mumbai is something I can never Forget.. where it rained more than 900mm in 24 hrs..😢
at 10:15 he says water doesn't make it slippery, but then says water gets into the pours and makes it loose friction? isn't losing friction effectively slippery?
Japan never cease to impress me. So many natural disasters and yet they're still doing so well. I can't imagine if these events happens in Europe, the continent will be wiped out, we do not have their skills to endure these natural events.
I think you greatly underestimate the amount of world class engineers in Europe. The EU has loads of environmental prevention systems, just look at the Netherlands.
But for the French. They would surrender. @@dengar96
@@systemsbroken france is an african problem
That's where this particular Japanese saying/worldview comes from, try searching "Use and Meaning of Shouganai(しょうがない) in Japanese"
Speak for yourself, dmbass.
I want to share a thing about rainfall that I learned some time ago which was quite surprising.
When I was younger and hearing about rainfall, I tended to hear two measurements: milimeters and litres per square meter. I always considered the latter to make more sense for me and I didn't put much more thought to it. Then, one day I thought to simplify the units of l/(m^2) to see what I get. A litre is a decimeter cubed which is 1/1000 of a cube meter. This gives us 1/1000 * m^3/m^2. The result is 1/1000 of a meter, which... is a milimeter! Surprise!
This will blow your mind:
The meaning of 1 mm water is, that if you put a container with straight walls into the rain, it will fill with a height of 1mm no matter how big it is. The bigger it is, the more water will fall into it,but also its area is bigger,and thus after all the rise in water level is the same.
And if you have a square meter sized container, filled to 1mm height,it will contain 1l of water.
So the units are literally the same
@@neutronenstern. This only works if the heights of each wall on the container are equal and/or the rain is falling straight down.
@@LeTtRrZ That is exactly how both the definition works and how meters work.
It's the same weird realization that fuel efficiency is measured by area when simplified. Which makes sense if you think about it.
@@person8064 That's true for metric. In US measurements it's inverted area, which doesn't make sense if you think about it.
Quality title.
Way more interesting than if you were actually just talking about the location that gets the most rain. Walking the line between clickbait (for clicks) and honest title (for transparency) is tricky, but you really nail it.
That is a marvellous piece of engineering. I'd be interested in seeing how the pumps works or how the water is recovered after the tests
+
the pumps work by generating pressure. Basically pushing water forward in the pipe.
The water is recovered through drainage in the floor.
case closed
@jonaswox you cannot have your run of the mill pump for what is shown in the video. And probably not only one given the uniformity of the rain throughout the warehouse
I've never been in a hurricane, but the monsoon rains in Eastern Arizona are the most intense, and painful rain I've ever been in. The raindrops felt like marbles hitting you. It only took a couple minutes to be flooding our town.
That guy running out into the rain simulator looked just like the rain in Eastern Arizona.
I think the word , trigger, you where looking for was influence... great show as always!! Thanks guys.... 😊 ❤❤
Hes so cute 00:25. Haha the way he run is like a baby boi
You are top comment for some reason
Why's bro got top comment
Top comment?
All Vertasium videos have been absolute bangers recently. For the past 6 months each and every video has been added into my personal reserarch-notes-for-worldbuilding playlists. They educate us on so much about the world and about people
What do you mean exactly? Are you collecting references for a story?
I studied a little about rain and landslide in Environmental Science course in my BBA study more than a decade ago. Good to see it again in this video. This keeps reminding me the importance of preserving the natural environment and the damage we have done to our home planet.
In 2018, A state in India named Kerala, experienced a greatest flood, due to the amount of rain and the sudden opening of the dams. Also, since some of the places were surrounded by mountains, landslides of greater intensity happened, causing the loss of countless lives. If, a facility like this is built here to study the rainfall disasters and prevent it in the future, it will be a huge benefit for the people living in Kerala.
This video is the exact representation of why I love watching Veritasium, They show us what we as humans have done, what we are doing & what should be do to prevent worst outcomes. The technical, physical & other aspects really binds it together. The main things humans should do is to plant more trees & reduce our wastage. I think all other problems can be sorted out if we can complete this one.
so, basically afforestation.
that segue from landslide prevention to the sponsor segment got me good. top tier!
*Really* intense rainfall never lasts anywhere near an hour. When it's really coming down hard, it's like standing under a waterfall (MUCH heavier than anything shown in this video; under those conditions, you wouldn't be able to see a man standing as far away, as he was from the camera), but it never keeps that up for more than a couple of minutes at most. 30 seconds is more typical. But in that 30-120 seconds, you can get several inches of rain. I've seen this happen three or four times in my life.
It does in some places
10:49 Water doesn't make the soil more slippery, but decreases friction between the [soil] grains.
So, by definition it makes the soil more slippery.
It makes the soil act as if it were more slippery and, in fact, can even become 'liquified' and move more like a liquid than a solid, say, a thick paste, but it's definitely not what you want foundations on. Just reducing the friction of a solid doesn't normally make that solid turn into a liquid, that's why the distinction is important.
The thing with science is that you need to be accurate, not just say « well it acts as if it makes it slippery so it makes it slippery » that’s a shortcut you’re not allowed to make
Something « slippery » has a low coefficient of friction. The water doesn’t lower the soil’s coefficient of friction. So no, it’s not more slippery. There’s just less force applied
@@kindlin I agree, but it also *does* make soil more slippery. The problem is in the usage of non-scientific terms.
@@books2438 "Slippery" does not have scientific definition. It is just relative term for perceived low friction. And water actually do lower soil's coefficient of friction (even when shear modulus is much more important in this topic). Google scientific publications about it or just walk on bare soil when it's raining. It is slippery.
13:33. Man, good thing you covered up the badge on the steering wheel. Wouldn’t want people to know it was a Tesla. 😂
As a child I promptly remember experiencing a rate of rain that was impossible to see through with even the wiper blades on full speed. I remember it as if the windshield was an ocean with waves and if that’s not the worst amount of rain I couldn’t imagine what they experienced
I was thinking the same thing. Couldn't hardly see my bumper, very sketchy 5mph drive.
They may have brighter lights on the other side to help see through it
@@GreenLightFlight yeah I was really young like probably 2 or 3 but my mom definitely had to stop driving but I didn’t really understand what was happening but it left a
memorial impact on me that I remember over 20 years later , I remember the rain and couldn’t imagine what someone who has experienced worse went through
I don't think this rain warehouse can match the intensity of nature. It's only when averaged over an hour that it claims that prize I think. Nature can be much more intense in short bursts like a minute or two. I've also experienced the unbelievably intense downpour that brings traffic to a standstill because nobody can see the road in front of them.
Talk about perfectly timed. It’s been shitting downwards with rain where I am right now for 3 days now.
3 days? That's
nothing.
I have never been more captivated by a channel I never knew existed. I love this content. Reminds me of SmarterEveryDay. Fantastic videos! Great information. Very well done!
Ive been to Tsukuba before. They do a lot of experimental research and it’s quite impressive. The natto there is awesome.
5:35 Can you imagine having a house fall on your house?
Every little kids dream in that shed, and bro the cameraman, never dies
10:44 doesn't "Decreases the friction" mean it's more slippery?
It’s the difference between putting a slippery pad under the legs of a couch vs lifting the couch up
I always thought that the wet soil is much heavier than dry, hence the gravity pull is stronger, so at a tipping point it overcomes the friction and starts a landslide.
Maybe a combination of both?
I think that probably contributes too.
Don't know how that well this applies here, but friction is calculated with the normal force, aswell as the friction coefficient. As the increading weight linearly increases the normal force and the force trying to start the landslide, it shouldn't affect things too much. (that assumes that every part of the slope is the same angle. But obviusly if you have a part of the slope that only holds because of the flatter slope above and below it, adding more weight will make it more likely to slide.
Ok, so I (over?)thought about it and I think what Derek & co were trying to say is that we falsely assume that when water falls on quartz, probably iron, and other particles that make up dirt, they become one. What actually happens is that it just fills in space between those particles. 'Absorb' is not what we intuitively think it is, to put it another way. The mass of water might cause an effect due to gravity, but it's much less than the loss of friction.
@@NoahBuehler I think you're right. I forgot that the force of friction is directly proportional to the normal force. I think the reason why I and OP ignored that is because the ground is at a slope, so the normal force vector would be at an angle, while the gravitational force vector is straight down. I'm too lazy to do any calculations though
11:38 We should be implementing all of these solutions anywhere and everywhere that's at significant risk.
United kingdom lore
I guess this is cousin from Japan
so close!💕 its Japan.
Philippines Lore
in "normal" places rain is measured in tens of cm. When rain is METERS it is unlike anywhere else, uk will never come close.
UK has no typhoons
6:43 someone jumping into the water
How did you notice that
@@FH_GAMING-Fares_Horani idk how he saw that
I am not sure what the definition of heaviest rainfall is used to get the rain at Holt at 1:51 but Nobby in Queensland, Australia had 203mm in 20 minutes in 1939. That's 50% heavier than the Holt rain. It also equates to about 600mm/hr which is double the rain rate in the "rainiest place on earth".
I've been on the receiving end of short bursts of 1-2mm/minute rain and I can't imagine what 5-10mm/minute would be like.
8:06 to skip the sponsored segment
Veritasium is phasing himself out with this new fellow
He may not want to burn out, and passing off the baton can keep the project of the channel going rather than shutting it down.
I like the new fellow better. He seems like a little bit less of a douche. I appreciate that.
So this video just got recommended to me and the algorithm is scary, not only am I currently under an evac alert for possible flooding, but i live in Pemberton where the landslides over the road photos are taken at 12:32
Great information as always, Derek. One nitpicky thing. Some B-roll tsunami footage was shown while discussing the effects of climate change.
I doubt he's going to listen to you.
@@tbird-z1r It was for you @turd81 so thank!
@@Pottery4Life Why you simp for the guy? What a weird parasocial relationship you have.
You literally addressed him by name.
Wouldn’t tsunamis be caused by climate change, thus being relevant?
2:08 304.8mm in 42 minutes is 435.4mm/hr. If the facility can only manage 300mm/hr then it can only simulate 69% of “the most intense rainfall anyone has ever experienced”.
Exactly what I thought when I saw that.
Yep and that was the average rainfall rate over that 42 minutes. The peak over some short period is probably much higher.
It only rained for 42 minutes and then stopped. That's an average of 304.8mm over the somewhat arbitrary one hour period. It would have been 435.4mm/hr only if it had actually continued to rain for that time, but it did not. You cannot simply extrapolate to an hour, because that is not the situation that occurred. An amount of rain bigger than those 304.8mm has not actually been observed over a period of one hour.
@@Ajyia I was not extrapolating anything. The rainfall rate during those 42 minutes was more than 300mm/hr.
@@redlopa1 So if you cut yourself, lose 5ml of blood in a second before you stop the bleeding, then in your opinion that means that it's reasonable to say that you just lost 18 liters of blood per hour?
As a general rule, if we're talking about extremes, it is never reasonable to extrapolate "x per y" to a y that's bigger than the y that actually occurred.
The hardest rainfall I've ever seen was in Denver Colorado in 1998. One of our workers came in to work absolutely soaking wet. Like just stepped out of the shower soaking wet. I asked if she couldn't get dropped off by our front door that was only +- 15 feet from the dropoff area and she said she had. I opened the front door and was shocked to see an almost solid looking wall of water with visibility of less than 50 ft but almost no wind!! I had to quickly shut the door as the water instantly started coming in. It only lasted about 10 minutes but we had over a foot of water in a well drained parkung lot!! I still shake my head whenever I think of it! The biggest raindrops... Miami Florida, Sept/Oct of 1976. 1 raindrop would spread across 30% + of my dad's front windshield. Good thing it was barely coming down, which is why I could see how big the drops were due to the very low clouds. Thanks for reading my memories.
filling the gap Tom Scott left -> informing the public about interesting infrastructure or related research facilities ^.^
Not forever
14:07
"As the world heat's up due to humanity's addiction to fossile fuel"
What a beautiful sentence... Yet terrible.
Kinda sums up why it’s so hard for humanity to decrease the use of fossil fuels
We love this! We appreciate the feature of our amazing wind tunnel technology and the STEM that goes into indoor skydiving! We have a passion for teaching students the physics of flight and we’re so glad we could help make learning more fun, the way you do! ❤
This explains how movies have it rain everytime someone dies and there is a funeral.
1 minute
And how American films always contrive rain in London, even though London has relatively low rainfall.
12:41 "Humans are REALLY GOOD at causing landslides, and we're shaping the land a heck of a lot more quickly than geologic processes do" sums it up so well.
There is always something to learn from your channel.
That guy saying water doesn't make things slipperier is just being pedantic. By preventing contact that provides greater friction, it does, in fact, make things slipperier.
He is not even pedantic. Otherwise, he would be able to see the contradiction. He probably just likes to oppose popular opinions. He is not like OtHeRs
Rain doesnt make it 'Slippery'..... it just 'Decreases the Friction' totally different
Aka makes it slippery
It’s the difference between putting a slipper pad on the legs of your couch vs lifting it
6:15 I have talked with Norway geologist engineer and scientist I have in my family. The reason is a clay, but it is the reaction for perforating thin earth surface by basements of buildings leaving water to penetrate deeper layers, under the clay, so the clay gets extremely slippery. Developers buildings are often built cheaply without any care about future, they are not secured against water penetration around them. A biiig problem in Norway.
Is it just me or does Derek's videos start of normal and then transition into calculus
The real reason we're taught calculus in school
almost like he's trying to teach us something
There was absolutely zero calculus in this video, so you're probably commenting on the wrong video.
@frankcl1 I know I'm just talking about other veritasium videos
No, he is a mster of the slippery slope. You start with a bit of simulated rain and then you landslide into university math.
"Why does it hurt to skydive in the rain?" You run into the pointy end of the rain drop
Your claim is misleading. There's a huge difference between "the most rain in an hour" and "the most rain ever experienced". I've seen rain considerably worse here in Tucson but for 5 to 10 minutes. It was hitting the ground so hard it was splashing up to my eye level and I couldn't see more than 20 feet.
10:50 I'm sorry but isn't water decreasing friction the same as saying water makes it slippier?
Dose holding a rubber above a piece of paper and moveing it makes the rubber slipperier? The water making distance between the soil grains not making the surface slipperier.
If I was a billionaire I would have one of these for my shower
Ahhh i get it…. For ur hundreds of wives?
3:00 nah, my favourite times in Maine are when big storms come through. Stuff like super storm sandy were my favourite, just because of all that water
The Batagaika Crater in Siberia is a good example of how deforestation can cause landslides. It almost a kilometer wide and looks pretty cool on satellite view on Google Maps.