A Hole Where You'll Freeze to Death | Geography of Extreme Microclimates

[@TheSaltyAdmiral]

When I served in the Norwegian army a large part of the training revolved around dealing with the cold. We learned to always dig a "cold pit" inside our tents, so that the coldest air inside the tent gathered there.

[@co.1157]

Cool

[@blackpantherjon9709]

@@co.1157literally

[@markwentz8332]

i've slept in a quinzee a couple of times when i was in cadets 30 years ago, gotta have that cold sink

[@malcolmyoung7866]

I served in Norway with ACE Mobile Force...'Cold holes' for 'The Win'(ter)

[@snailart14]

We live in a an old farm house that my great grandpa built, and we have "two" basements, one is where all the pipes are and we keep it heated and then the other we actually leave the door open in the winter because we don't use it as a cellar anymore it's where we let the cold go. It's not antarctica but we live in Minnesota lol

[@lemonworm]

This is the exact level of budget and informativeness I want out of educational videos. No over editing, no dramatization, just a guy explaining the thing with some diagrams.

[@stevenjohnson7086]

Yeah, that’s how school used to be. Just like this.

[@indigenoussober407]

Yeah but remember the Eyewitness videos from school?

[@DJ_POOP_IT_OUT_FEAT_LIL_WiiWii]

Boooooorrrrrrrrriiiiinnngg

[@glitterytrinket6246]

Agreed. More videos please.

[@MA-go7ee]

I avoid most KZbin 'science' channels because of the overdramatisation. It's so grating. I'm just thinking 'Hey this is what we DON'T like about television'.

[@DreQueary]

I love the no frills presentation of this video. No music, no goofy transitions, no annoying sound effects to get viewers "engaged". Just straight up informative. It's like an old school PBS documentary.

[@laurasalo6160]

Yes! Right! Im not a toddler - i dont need colors or sounds or anything "attention grabbing"- i just need info. Clear and concise. Good info is entertaining enough!

[@parrotshootist3004]

​@@laurasalo6160or sanitised for infantilised manipulated audiences.

[@stellr88]

@@laurasalo6160But, i love to toodle! is it not cool now to be a toodle-r ?

[@laurasalo6160]

@stellr88 lol you got me 😀

[@parrotshootist3004]

@@DreQueary not only my comment gone, but the replied to comment that brought me back is gone. Lol

[@Redbikemaster]

I'm a trucker that frequently crosses the western US. This makes my winter experiences make so much more sense. Thank you for this video. I've driven through multiple cold hollows but never fully understood what was happening.

[@twointhepinkoneinthestink]

Keep on filling up those empty Gatorade bottles, Driver!

[@Redbikemaster]

@@twointhepinkoneinthestink you know it

[@cartergomez5390]

Wow! Where are the coldest hollows that you have driven through? I once drove through Oregon at night and I remember it was really creepy with trees hanging low and much smog. It looked like a scary movie and I have would never drive there again!

[@jonahshriver1682]

​@@cartergomez5390that creepy feeling isn't just the environment. Oregon has a long and vile history of cult activity throughout the state. There's also sacred native American land there. It's a very spiritually charged place.

[@curtsiekert]

I agree. I remember one morning heading to La Crosse, WI and when I would dip down into a little valley the temperature would drop twenty degrees and then come back up again and then back down. Lol. I didn't know what to make of it and basically forgot about it until now.

[@berrodude]

Its also worth note that these depressions, often surrounded by elevated terrain, sees much less sunlight in a day cycle, thus reducing the time the ground spends heating, further contibuting to the cold..ness of these areas.

[@hainleysimpson1507]

So keeping meat down there is a good idea? In a secured container buried in the ground of the frost hollow.

[@joeg5414]

that was the first thing I thought of. I live in the mountains in SW Colorado. Often times these areas will hold snow for a lot longer because they don't get much sunlight

[@curtsiekert]

I think he hints to that in his video.

[@naverilllang]

​@@curtsiekertYeah I thought he was going to say something like that. It kind of feels like he just forgot to write that part of the script. Or was cut for being distracting from the main point

[@TitaniusAnglesmith]

I've made the mistake of camping in a hole before. Didn't have a thick sleeping bag because it was summer. The coldest I've ever been in my life.

[@interstellarsurfer]

At least it was summer. 🤷‍♂️

[@whatare9731]

why are all of the replies to this 1 year old comment within one day of each other?

[@TitaniusAnglesmith]

@@whatare9731 Algorithm works in mysterious ways

[@interstellarsurfer]

@@whatare9731The Algorithm resurrected the video, and we did a little necro-posting. It happens.

[@jarcake6581]

Love the cold to death

[@Draxis32]

Curious thing to notice. The lowest temperature ever recorded was measured in Antarctica in a similar condition. Cold air trapped inside holes in the mountainous ice sheets.

[@douglassperlich6329]

Actually the coldest recorded temp was at the Russian station vostok. It's located on top of the antarctic plateau. -88 C.

[@Draxis32]

@@douglassperlich6329 That's the measured on the floor. However sattelites can use infrared spectrometers to measure temperatures pretty accurately. And it was -90 C I believe somewhere in the plateau of Ice.

[@stratospheric37]

​@@Draxis32 isn't measuring from satellite considered less reliable than measuring on the ground?

[@Draxis32]

@@stratospheric37 Indeed it is. However the temperature described is likely to be colder than the previous record. I believe the margin of error is only .5 C meaning it could have been 89.5 or even 90.5 C below zero. Both are lower than the previous record.

[@douglassperlich6329]

@@Draxis32 interesting. Didn't know that! Thank you

[@Val_Emrys]

I learned about this phenomenon from reading Louis L'Amour novels. His main characters always made a point to camp overnight halfway up a hill because they knew the coldest place was at the bottom of the valley.

[@MrReymoclif714]

Rivers in June Vermont are quite cold!

[@smc1942]

I read those books as a kid, and years later continued that practice of keeping OUT of the low laying area! It saved me more than once!

[@FightingForFacts7074]

This is a great example of practical knowledge delivered in an entertaining way. Descriptive literature is educational!

[@marcmenard9121]

Aghh, very wise. Thanks for the comment mate.

[@aliannarodriguez1581]

@@FightingForFacts7074It can be, if the author researches the period and setting for their novels. I know that such research by authors of fiction was considered a fundamental part of writing at least up through the 80s. There were even people paid to fact check historical, geographical, scientific, etc. information that was either stated or implied in the novel. What I don’t know, is whether this is still the norm in publishing. It’s definitely not true for a lot of the self published stuff you see on Amazon.

[@NiSiochainGanSaoirse]

This was incredible. This is PRECISELY what I was searching for. No ads, no unnecessary dramatics, or annoying music, just a video with continually informative viewing. Excellent.

[@callmedax6532]

And he's talking at a normal pace! Such a relief

[@TheWtfnonamez]

This is fascinating. As a camper I am always trying to choose that "perfect pitch" whilst being worried that Im actually choosing a death trap. Nobody wants to get flooded out so they camp higher than the stream, so you find that spot that is elevated, then you worry that you might get blown down because its so exposed, so you choose some lower, protected, spot, in a depression. .. which might actually be dangerous. Thank you.

[@ant9610]

Phenomenal video, glad I got recommended this channel.

[@tothesummit5864]

I've been camping and backpacking across the Western US for over 50 years. One of the coldest nights I ever spent was when I pitched my tent in one of these zones at the bottom of an alpine valley along the High Sierra Trail in August at an elevation of about 10,000 feet. At the time I had not yet learned of this phenomenon and couldn't understand why it felt like I was camped inside a commercial walk in freezer, especially since it was deep summertime. At the time my reasoning was that if I got to a low spot I would be protected from the wind. Being summertime I was not prepared for extremely cold temperatures. By contrast, a few days later I was camped at the summit of Mt Whitney (14,495 ft) and it was rather pleasant all night long.

[@gregparrott]

Having it warm when camping atop Whitney likely means you did this in July or August. I noted the same camping in late July at the base (12,300') of another 14er just north of Whitney (Mt. Sill), adjacent to the Palisade glacier. Even at midnight it was T shirt weather.

[@FlyGuy2000]

I have experienced the same thing when camping out in an open depression so that I can stargaze at night. Despite late summer temperatures I have often woken up to frost on the inside of the tent that collects into a softball-sized ball when shaking it out in the morning.

[@vincentcleaver1925]

Warm air from the summer slopes of valley kept rising all night

[@HarrisonBurgeron-h9m]

White Sides Meadow in the Emigrant Wilderness fits this description perfectly! The Emigrant borders Yosemite Wilderness along the souther border, all very high altitude with meadows and saddles at 12,000+ feet. I was on a trail crew, we lived and worked out there from May to September continuously, food and supplies were packed in by mule, on days off we hiked and explored. White Sides meadow is like 9 or 10 thousand ft, its circular with a high ridge surrounding about 80% of its circumference. Its was early June and everything was still under a deep layer of ice and snow, at that altitude in the Sierras winter lasts damn near til august some years. It was around 5°f overnight on the nearby peaks and saddles while just 2 miles downhill in the meadow our thermometer was hitting -28°f. Growing up in the Sacramento valley snow was a once a decade phenomenon and even in the coldest winters it would barely get to the frost point and only maybe a couple dozen nights per winter season...So that negative 28 degree night was a unique thing for us to say the least...Its gave me a whole knew idea of what Cold truly means.

[@walkerig1]

My wife and I were almost killed by such a Frost Hollow. In October the most beautiful time to visit the Dolomites of the Val De Gardenia on the Italian Austrian Border. While climbing and taking a Via Ferrate there; we decided to camp next to a small stream that flowed in to the hollow in the ground, in the clearing of a beautiful alpine meadow as we thought. Under an awning not a tent watching the stars. During the night my wife said she was cold. We both ended up together on both our empty rucksack with both our sleeping mats on top of them. All our clothes on thermals, two pairs of trousers, two thermal mid layers, two fleeces, Gore-Tex jackets three pairs of socks, four in wife's case, double layer gloves, both of us crammed into the two sleeping bags one around the other, the zip stitching ripped on the outer bag. And the awning wrapped around us. and a large orange survival bag outside that. We spent the night with our teeth chattering. Never were two people happier to see the dawn. When we got up the 1.5 foot deep stream next to us had frozen solid. When we got back to civilization we bought two 4 season down Himalayan expedition sleeping bags, silk thermal liners, the best sleeping mats. And vowed never to go into the mountains without a tent. Two mountain guide friends later explained to us about frost hollows. This should be mandatory for anyone who goes into the wild.

[@jason2014]

Sounds cold, but I don't think you were almost killed. If you're sharing body heat with someone as you were, you can handle much harsher cold than you did.

[@Alex-ph1gb]

It's actually better to wear less clothing inside a sleeping bag

[@walkerig1]

@@Alex-ph1gb Normally yes but not in this case.

[@kitano47]

kek calm down you were fine, tom hardy slept in a dead horse

[@ATruckCampbell]

@@kitano47 Have you ever even slept outside? You can freeze to death in 40F temperatures if you do not know what you are doing.

[@Meanie010]

When I first started riding a motorbike I began directly experiencing this, I'd be riding through the mountains at night, and dip into a valley. At the bottom of the valley the temperature would drop by 10-15 degrees or so in seconds. Rather spooky when you aren't expecting it.

[@Mdeaccosta]

Yes! I call them Cold Snakes because they lay across the road. There are two dependable Snakes just west of me, brrrrrr. Popping back up out of it feels great, though.

[@wingman358]

I loved that about riding. You're much more in tune with the outdoors when you're outside of a cage!

[@chongtak]

There is that, and there is when you approach a river. The proximity of a river at the bottom of a valley must be very cold.

[@Mdeaccosta]

@@chongtak the river is very close, and yes. The odd thing about the big river bottoms is that the wind will roar overhead 40 mph like a jet, and it's still as death on the ground.

[@tomvana4270]

Motorbike? Motorbike? Brittish jibberish.

[@suesmith5746]

This also happens on a smaller scale everywhere even in cities. I live in a city built on a tight u bend on a fairly large river. The Native Americans and early settlers lived at the summits of surrounding bluffs or just below. This avoided floods and is significantly warmer. I live on the top of one of the highest bluffs, other homes and commercial buildings around me help decrease the wind, but are not dense enough to affect temp. In the fall when we still have flowers blooming, we watch the forcast and cover our plants if a freeze is expected. My nephew lives 50 feet above the river, I live 3000 feet above the river. I have 2 extra weeks of warm weather and flowers every fall. The average overnight temp difference is 8 degrees F. We live about 2 miles apart.

[@mvtorigian4364]

I'v typically avoided camping in holes due to potential rain funneling or snow accumulation. Thanks for making my outdoor experience more informed all the same.

[@notlohhcaz]

These things he’s speaking of really won’t look like holes from the ground..

[@evanlucas8914]

There are at least 2 similar phenomenon called "ice mines" in Pennsylvania. They are deep caves that thaw in the winter and grow ice in summer.

[@john-ic5pz]

I'm from PA and never knew this. thanks!

[@evanlucas8914]

@@john-ic5pz yeah they're kind of niche and out of the way. Besides when it comes down to it it's essentially a hole in the ground with summer ice. Not much to look at visually but definitely mentally intriguing.

[@joecat916]

I heard of the Couldersport ice mine! Where is the other one?

[@FifinatorKlon]

That is what happens if you go for bullshit like the Fahrenheit or Kelvin system.

[@evanlucas8914]

@@joecat916 Trough Creek State Park. It doesn't work as efficiently as the one in coudersport but it does still form ice most summers.

[@Erik-ri3gz]

I don’t know why KZbin suggested this video to me… it isn’t part of my normal listening repertoire, but this was incredibly interesting. You presented it well and the physics make perfect sense. Thank you for making this. I learned something. I’m going to start working my way through the rest of your library. If they’re half as interesting as this effect, it will be time well spent.

[@realityjunky]

Watch out, dude. Geography is secretly totally addictive!

[@joshsalwen]

I’m with you. I didn’t know that I wanted to know this.

[@GeorgeSukFuk]

Welcome to KZbin

[@dalemoses2443]

So this is why San Fran is so cold and foggy? It’s the outflow from the California depression crashing into the ocean.

[@chir0pter]

@@dalemoses2443 no it's cold and foggy because of upwelling. I could believe the narrow SF outlet and interaction between topography and wind did play a role in funneling that extratropical cyclone's eye directly over SF last winter tho

[@Quadrenaro]

I live in one of these, in the Yellowstone region. It get's very cold, very fast. A Canadian fellow I met couldn't believe how much colder we were, despite being 800 miles south of his town. We've had more than a few tourist think an easy hike, an hour before sundown, would be a simple in and out adventure, only for S&R to find them dead the next morning.

[@scottoshea9440]

The fact that you live in the Yellowstone region and you're still alive proves you're a survivor. All dumb people are quickly weeded out with a Darwin award in that area.

[@DreamseedVR]

Dark

[@Quadrenaro]

@@DreamseedVR Yeah, alot of crap happens up here that doesn't make national news.

[@ape589]

@@Quadrenaro Man I know what you mean, in Colorado there's always people who are woefully unprepared and overestimate their abilities not knowing what its like with the altitude and weather...

[@Nick_Taylor.]

I went to Yellowstone in mid September 2021. At around 2pm I was wearing a light sweater watching the Old Faithful geyser. By sundown I was driving off the premises toward Cody WY, and I was stunned to see snow cover the ground beside the road.

[@colebevans8939]

As a Canadian who loves the outdoors I learned this right from a young age. I always set up camp on top of a ridge or hill when possible. It’s warmer up top and if it rains you’ve got good drainage. I’d rather walk 3-4 minutes to get water then be up all night because I’m wet and cold.

[@hotdog9262]

wind and milder cold, is worse then just extreme cold imo. id second camping on a terrain uphill `bump` though. purchased my house with the same thought process on location

[@ATruckCampbell]

Isn't it windier on the top of a hill or ridge though?

[@mfallen6894]

One of the best videos, on a phenomenon I was totally unaware of, I've ever seen! No idea why YT rec'd it 2 years later, but I'm glad they did!

[@sazji]

This is actually something gardeners in Seattle with its microclimates are keenly aware of. Or if they aren't, they'll learn! Seattle has several areas that function as "frost pockets," where lows are frequently significantly lower than other areas. Not as intense as the ones in the video, but if you live in one of those areas and are relying on your climate zone in planting, you'll be in for a rude awakening!

[@ThatSB]

The hell is "relying on your climate zone" lol. Hopefully the low temps will keep the riff raff from setting up a homeless camp

[@HarrDarr]

@@ThatSBforgot to take your meds this morning, gramps?

[@aliannarodriguez1581]

The first time I heard about this was when I in connection with permaculture. I had been gardening for years, but had never been aware of it. I kept it in mind though when situating a fig tree in a borderline climate and it’s paid off so far in avoiding winter die back.

[@sazji]

@@ThatSB "Relying on climate zone" means looking at a climate zone map, finding that "Seattle is zone 8b," and thinking that necessarily applies to your neighborhood.

[@themackenzies5079]

​​@@HarrDarrhe said homeless camps because Seattle is a woke 3rd world dump where the homeless fuck like dogs in the street and shit on the sidewalk. Would you like that in YOUR garden?

[@EdwardHamiltonDavis1]

So well done. This high-quality video is just the stuff good teachers look for to supplement their classes. Excellent work.

[@georgeofhamilton]

Mediocre teachers have their students watch other people’s videos to learn; good teachers can teach the same material just as well by themselves.

[@yourmom9951]

@@georgeofhamilton Supplement this 🍑💨

[@jamescerone]

@@georgeofhamiltonthat’s a bunch of absolute bullshit. A good teacher recognizes when someone has created a great, succinct piece of content that will benefit their students, instead of wasting time putting together the same thing just to say they did it themselves. And nobody can be perfect at explaining everything, and most teachers do not have the time and resources to put together complex visuals for every single bit of their lesson plans. Entire businesses are predicated on providing supplemental material to teachers ya fucking nitwit.

[@leothenomad5675]

​@@georgeofhamiltonGood thing George said supplement the class and not use it in place of.

[@PippetWhippet]

@@georgeofhamilton One single teacher isn’t the perfect teacher for every child. Some children might learn very well from one teacher while other children learn poorly. Unless your school can afford three or four teachers for every subject, something I saw in the uk but my country cannot afford, then supplemental materials are very valuable and a good teacher will use them because a good teacher understands that not every child is the same.

[@chadnelson8259]

This is why Truckee, CA can get really cold at night compared to nearby towns. The cool part about the area is the Tahoe basin is the inverse and it's only 15 miles apart and a higher elevation. Towns around the lake will be 20F warmer in the winter mornings b/c the lake is a massive heat sink

[@yoeyyoey8937]

Never knew that but it makes sense why people like living there during the winter

[@Adam-kn3tv]

Same principle, but higher up so the hot risen air is what pools in the Tahoe basin instead of the cold sunken air trapped in Truckee. Fascinating. 😮

[@marcmenard9121]

Good share. very true

[@missano3856]

If you watch the national low temp it seems to start the winter in Truckee, then Gunnison CO, then Wisdom MT before alternating between International Falls MN and Caribou ME.

[@davidnovak707]

It (the national low), does seem to rotate amongst those cities/areas. Good observation.

[@RinceCochon]

A similar phenomenon occurs where my family comes from, in the French Jura. During the winter, it can be 0°C in a village, and -25°C in the one 10km further, located in what are called "trous à froid" (cold holes, in English). The record was around -40°C if my memory serves me right. For a country like France it's quite unusual, even at altitude it's (in general) warmer.

[@meteo17100]

Mignovillard, Combe Noire ?

[@NiSiochainGanSaoirse]

I remember going up mont Chamonix, to the bridge and cafe, and being shocked at just how war it was! Despite being on top of an alpine mountain with snow everywhere.

[@ericmilman5812]

I grew up in Northern Utah and was asking myself if this was what happens at Peter Sinks, then you brought it up! Really informative video.

[@OlDoinyo]

Peters Sink and Middle sink are very similar. It got down to -69F in 1984 there. They are pits caused by collapsed caves at high altitude.

[@jdhd2837]

I saw this video and immediately recognized it as what happens in the Sinks! Neat stuff.

[@davidconner-shover51]

Thanks for mentioning the San Luis Valley The winter of 2011-2012 was the coldest I've experienced in my life. My folks live a ways South of Alamosa, not far from the Rio Grand right above where the river squeezes between the mentioned volcanoes. Mid -40F every night for a week, the propane quit working, we had 2 wood stoves cranking out full blast the whole time in an 1100sqft home, it was brutal.

[@johnbauer9480]

I recommend Ted Conover's book "Cheap Land Colorado: Off-Gridders at America's Edge", set in the SLV. Brutal winters, tough living. Pro tip: don't brush your teeth with a frozen toothbrush.

[@davidconner-shover51]

@@johnbauer9480 I'm familiar with the writer, and some of his interactions with my folks neighbors. My folks moved there back in 2010, they get by. Nowadays, they have all the modern conveniences, though power is a bit limited. The last bit was a well they completed last winter. Some mistakes made, mostly overcome. I helped out with installing and maintaining the utilities, power, water, internet....

[@SuperlativeElectric]

@@johnbauer9480I’m curious on why not to brush teeth with a frozen toothbrush. I’m guessing the bristles would become to rigid and abrasive? Let me know!!!

[@Mummymunmuggy]

The SLV is beautiful. And yes, very cold in winter.

[@davehughesfarm7983]

I just ran all over that place from half up Mt. Blanca, down to San Luis, South and North of Alamosa. Interesting, bizzarre, strange place....Glad I explored it but now know why 5 acres is only $4-6000 bucks...

[@Rayrard]

I have a spot where I look for insects in CT where it gets much colder at night even during the summer. Then you walk out of the meadow and it's warm. It's a limestone area and a calcareous fen which is likely one of these cold traps. The cool part is that there are moths there that are found in VT and Maine but not anywhere else in CT or Mass. Likely they are relictual distributions.

[@asafoetidajones8181]

Roughly where, if I may ask

[@jkbrown5496]

The flow out of the CA central valley across SF Bay is interesting. Explains Twain's remark “The coldest winter I ever spent was a summer in San Francisco”

[@kalyxo_tb]

That specific situation is actually due to the cold California ocean current mentioned in the video (during the bit about oranges). As a peninsula, San Francisco does not experience the effects of cold holes but is very highly affected by water temperature. In fact, very cool summer temperatures are a constant all along the Pacific coast, excluding bays, down to the western Channel Islands (the main current flows along the outside of the Channel Islands so the effect on Socal is weaker).

[@mbasecke]

This is truly a marine effect, and simple physics. As the interior heats up intensely at midday the air rises and draws in a sea breeze. The combo of cool and breezy can be quite unpleasant. As this mechanism fades in Autumn, the Bay Area gets some exquisite weather. When both the 49ers and Giants were based at Candlestick Park, the football team would often get more enviable weather. In fact, one season the Giants had a promotion where they passed out badges that read something to the effect, “I survived a night game at Candlestick”.

[@ferretyluv]

@@kalyxo_tbThat explains why I hated going to the beach on the west coast as a kid. The ocean was always so cold and the waves so big and choppy.

[@PastPerspectives11]

@@ferretyluvI had the opposite experience. Traveling to South Carolina from CA and finding how warm and tepid the water is was a nice surprise.

[@rosethorne9155]

Oh yeah, depending on where you come in California, some places here used to have frost on the grass well into midsummer. Youd never know it, because about fifteen minutes away, there are chaparral hills where it will be 100°F in the heat of summer.

[@monique993]

This video felt like sitting inside in a comfortable chair with a blanket. That was so relaxing. Thank you. The voice, slowly explaining everything bit by bit and not information information information in an annoying loud tone. Thanks again. That felt good.

[@Purrfect_Werecat]

so easy to forget the atmosphere may not be a liquid but still fluid

[@auctumnus]

EXTREMELY cool video. i'm not an earth sciences person normally but i couldn't stop watching, i was unbelievably hooked hearing you explain things that end up being super obvious in hindsight. it was really cool seeing the same concept applied again and again to show off different ways microclimate can effect life

[@mikeoglen6848]

It's surprising what you can learn, isn't it?

[@fjb4932]

​@@mikeoglen6848 More surprising, is what people refuse to learn. ☆

[@spacecoyote6646]

I get it. Cool video. 😂

[@TheGreenGrower618]

I learned this the hard way when I was about 17 and decided I was old enough to go camping on my own for the first time. I Hiked out about 10 miles into a national forest and decided to set-up in a deep valley surrounded my ridges. The forecast low for that weekend in the area was 40* so I brought a cheap amazon 40* sleeping bag and planned on just sleeping in the jeans and t-shirt I had on. It had been in the 70's and Sunny that day but by 11pm it was already 28* in the valley and I'm sure it got even colder during the early morning hours. It was the coldest I've ever been while trying to sleep. I couldn't stop shivery. All i brought to sleep on was a thin fleece throw blanket i got from a clearance bin for $5. It did basically nothing to insulate me from the ground which was freezing. My idiot teenage self thought that putting a mylar space blanket under my tent was going to insulate it from the cold ground. If it wasn't for my nearly 100lb dogs body heat it could have been a seriously dangerous situation. I wasn't even going to let him in the tent at first because it was brand new and he had torn up my last one but i ended saying F it because I was so cold and let him in. I wrapped us both up together in the fleece blanket the best I could to trap our body heat and we made it through the night but it was pretty miserable. I spent all the next day moving camp to the ridge top which didn't get nearly as cold as the valley had the night before. About 15 years later I let my son use that same sleeping bag on a boy scout trip and he said he nearly froze to death on a 50* night so that sleeping bag must have really sucked. Cheap sleeping bag temperature ratings mean nothing. Lesson learned. Now days im older and my comfort is more of a priority so now I have an insulated extra wide sleeping pad on a wide cot with an oversized down bag for cold weather camping which i love now that I'm properly prepared.

[@carl8568]

That's character building experience right there 😬🙈🥴

[@whatthepick]

Passing the lesson of a quality sleeping bag to the next generation :D

[@casualearth-dandavis]

Another large, nearly enclosed valley (and a frost hollow) is in central Alaska, through which the Yukon river flows. On the banks of the river is Fort Yukon, which has the lowest monthly mean temperature ever recorded in Alaska and the United States.

[@KenFullman]

Excellent content. This may have already saved someone's life. 0:30 "Well drained, low lying meadows seem like the most inviting camp sites at first glance" They would definitely have fooled me.

[@MVargic]

Jack London's To Build a Fire, one of the most visceral portrayals of the deadly danger of cold is set there, with temperatures below -60 C

[@firstlast-cs6eg]

How come some valleys are warmer or more mild cold wise? Just lower elevation or something to do with it being a valley? Like I get that cold travels down and collects, so why would the reverse be more common?

[@lancenutter1067]

Yah I lived in Alaska for 30 years, near Fairbanks. I’ve seen -68 in, I think about 1989. It was a record. But the whole valley is colddddd. Interesting topic !

[@Chris_at_Home]

@@MVargicI grew up in Connecticut and always remember having read that in a school English class and then got to experience that cold. Who knew after serving an enlistment I’d move to Alaska and worked in the Arctic over 30 years. I worked in the oilfield and along the pipeline. I worked at a pump station 20 miles north of the Arctic circle for 6 years. One time the helicopter mechanic/weather observer and I told he fancy mercury thermometer and went down the bottom of a hill and it read -67F. My job had me driving in all weather and I’d take the temperature probe of my Fluke meter and tape it to the outside mirror and watch the temperatures change 30-40 degrees between the top and bottom of a hills. We used to snowshoe after work in temps down to -30F.

[@TheHuntron2000]

Arizona has a few areas where this phenomenon happens too. But we have another, the coldness that happens it flat open desert at night. Summer temps can be 115+ in the during the day, but can drop to the 30-50s at night. Camping in a desert valley is brutal at times if you aren’t prepared. We always camp next to ridges or on mesas

[@AaronHendu]

O C camping is easy peasy my man.

[@orinthiamartin1189]

2:10 I experience this every night on my way home!! I ride my bike back home after school and sports, so it's late out. My route takes me from the top of a hill to a ravine, and the temperature drops by what seems to be 20 degrees. It's insane how quick it is.

[@casualearth-dandavis]

User u/Shonuff8 on Reddit has noted another great example: The Canaan Valley in West Virginia, which recorded freezing temperatures in late June: www.washingtonpost.com/weather/2021/06/23/summer-freeze-canaan-valley-wva/ due to its semi-enclosed terrain.

[@ronjaj.addams-ramstedt1023]

Thank you from a new subscriber - this and all the other videos that I have watched have been extremely interesting!

[@helmutzollner5496]

Very interesting. Had not realized that. I had thought the stunted growth in these clearing comes from browsing animals who eat the grass on the.meadows and snack on pine needles, but the consistent size of the stunted trees does point to a different reason. Well researched. Thank you for sharing.

[@user-iu2um8fd8n]

I'm not sure if it's the cold, because it's very rarely extremely cold there. The area is used for agriculture and mown, the grass is used for animal feed, so no trees or bushes can grow at all, regardless of the climate.

[@NormalPersonCommenting]

I learned this while camping once; I found an area with a roughly 6 foot depression (maybe 50 feet diameter) and camped there in mid-Autumn. It was a cold night, but you could climb the embankment and it felt fine up there. Much smaller scale, but the same cause.

[@d36williams]

yikes I'd avoid such a space because of hydrogen sulfide fears, but maybe that areas doesn't have long sustained heat and moisture

[@pearlybee944]

⁠@@d36williamsCould you please expand on your comment. Would love to learn more about the dangers involved.

[@ThrowawayModeller]

I've been travelling on the road from Mittersill to Lienz with my friend a month ago and despite it being 25C in Kirshdorf, when we were driving down the road to Lienz the temperature dropped to 5C! I knew it had something to do with the mountains, but had no idea what. This really helped clear out that mystery and now that I think about it - it makes perfect sense.

[@redmesa2975]

I’ve hauled oranges out of Reedly California. Miles & miles of orange groves. 7:29 I live in Western Colorado. Vail gets colder than Aspen IMO. Vail sits in an east / west valley. The wind whips through there. Aspen is surrounded by mountains, a bowl. Don’t seem to get as cold there, relatively speaking.

[@Elephantine999]

I camped at the bottom of an alpine valley once and amazed at how cold it got--below freezing after a warm day. This helped me to understand why. Really interesting. 👍

[@byroncreek]

This effect happens even in fairly warm climates. I live in Sydney Australia and different parts of the city can experience large temperature variations on a winters night. The coastal areas never go below freezing, but low lying suburbs in the west at the base of the Blue Mountains can go as low as -5 degrees Celsius. Cold air just rolls down the mountains on the west side and are contained by hills to the east. A heavy morning frost results from this. The mountains can often be much warmer and stay above freezing. Other places in Australia can experience this, typically closed off valleys within high mountains just as explained in this video. The town of Cooma in southern New South Wales is notorious for this, being in a valley below the high Snowy Mountains at times it can get down to -10 degrees Celsius during a winter night!

[@carl8568]

I'm at 560m elevation in the Victorian high country and the wind can be absolutely insane on my bush block, but I hardly ever get frosts. A short 3km drive down a 4WD track in to the township and it's almost always cooler.. 3 odd °C. I do, rarely, get get snow up here though where as the town, nestled in a deep valley, will not.

[@sirvalhart7464]

Omg I stayed in Cooma in like September a couple years ago and I was freezing my ass off. I live in QLD so my extended family had to put up with the biggest sook that week

[@ankitgu56]

Excellent first video to your channel that I enjoyed and learned about the cold spots I didn’t know existed. Hope to see more content over time.

[@mbasecke]

Having lived in California’s Central Valley, I can attest to some of its peculiarities. The thermal belts of the Sierra foothills are promoted by realtors as “banana belts” or “below the snow and above the fog”, yet they remain sparsely populated. Most all the big cities are essentially on the valley floor. Orange groves are located there, but they are equipped with huge fans that mix the air on cold winter nights, drawing down the warmer air tens and hundreds of feet above groves. When an unseasonably cold airmass invades the valley it can linger for days as the denser cold air is trapped between the mountain ranges on three sides (Sierra, Diablo, and Tehachapi). In summer, Bakersfield typically “bakes”, but heating is often more intense in Redding hundreds of miles north, because, even though both cities are surrounded by mountains on three sides, prevailing winds subject Redding to adiabatics effects (down sloping winds compress air as it is squeezed through mountain passes) more frequently.

[@Inkling777]

Many thanks for explaining something that mystified me. Years ago I did a winter hike at Mt. Rainier National Park. I set up a tent looking down on a frozen lake and was surprised that the night I spent, while cold, wasn't as cold as I expected. After watching this video I understand that that lake served as a hole drawing the cold away from me. You might want to examine this phenomena from the opposite angle-using holes to keep yourself cooler in very hot environments such as deserts. Does that work as well?

[@JayR-wg9jq]

yeah, it works. that's why all the wildlife that lives in the sahara desert resides underground during the day and why caves are generally considered cold and wet. on a smaller scale, when i was a kid and i lived in an area with hot summers and not a lot of central AC in housing, people would sleep in the living room during the summer instead of upstairs in their bed.

[@echo-channel77]

Anyone who has lived in the desert and drives through rolling hills in the late evening can feel this by sticking their hand out of the window. It's incredible how only 100 feet top to bottom can make. In the trough, it can feel quite cold, but as you drive to the peak, it's nice and warm.

[@wtywatoad]

It was during the 3rd week of May many years ago when we camped in the San Luis Valley during our bicycle tour. We awoke to a heavy frost that nearly collapsed some of our tents.

[@mindcoloredSLV]

Where in the valley? We have some property near Crestone so very curious.

[@wtywatoad]

@@mindcoloredSLV Not far east off of 285. North of Alamosa but closer to Hooper. That was 1986.

[@haileybanks306]

I love that valley with all my heart! Soooo chilly at night!!!

[@irisjanemay1903]

I spent a couple winters in San Louis in the San Louis Valley. One winter it snowed in October and didn't melt until May. Every night we'll below zero.

[@MatteoTN]

Well done video ! We have such "frost hollows" here in Italy too, both in the Appennines and in the Alps. Some sinkholes record lows till -35°/-40°C even just at 1.200-1.500m altitude.

[@riograndedosulball248]

My actual god damned house sits in a hole just beneath a mountain. It's ALWAYS at least five degrees colder than elsewhere, even in summer. In winter, well, nights are not nice

[@Birbucifer]

@@riograndedosulball248 gimme that over louisiana weather anyday. i'd rather freeze to death than be a blood bank host for a colony of mosquitoes as the rest of my body moisture is converted into sweat

[@ivanlagrossemoule]

We've had -41.8°C recorded at the Brévine in Switzerland too, and it's barely above 1000m. Record temperatures close to it at the same altitude are generally around -25°C for comparison.

[@riograndedosulball248]

@@Birbucifer here is the catch of my location: I am in subtropical Brazil, it's cold enough to snow sometimes, but enough not to kill all the mosquitoes. As such, part of the hole is a bog that keeps breeding them on forever, so in winter there are some mosquitoes and in summer, I am trapped down here with a cloud of them that cannot disperse. I drew the short stick of inherited farmland

[@DC_DC_DC_DC]

​@@riograndedosulball248dunk sufficient clear mineral oil (just like baby oil/candle oil) on the water to form a 1mm thick layer all over. Or a school of small larvae eating fish

[@troismoutonsetuntigre5988]

This was super fascinating, thank you. I love that you include terrain maps. I grew up in a house that was built in one of these cold holes, the temperature on our property was often ten degrees or more colder than the upper plateau just 5km away.

[@liammurphy2725]

I live in a very built up part of London England and am familiar with my local 'frost hollow. It's only 3 streets wide and about 200 meters long but it's cold enough there that I feel sorry for the folks who have to step out into it on a winter's day. Thank you for telling me a bit more about it.

[@Dave-hu5hr]

metres*

[@liammurphy2725]

That's what I get for growing up with gas and electric meters. Thank you.@@Dave-hu5hr

[@mattturner6017]

I once saw this thermodynamic phenomenon! Unusual circumstances saw me driving past a nearby canyon early in the morning, and in the barest light of pre-dawn, I saw a river of fog flowing out of one end of the canyon and into a broader valley where the fog filled a depression forming a kind of fog-lake. Then, of course, the sun rose and evaporated all of the fog.

[@Mike40M]

Not extreme, but where I live, this effect was known at least in the13th century when they decided where to build houses. My early 18th century house is situated on an iceage ridge. In a small 12 metre depression just 50 metres away, winter temperatures is 2 centigrades lower. Makes an impact on amount of firewood needed for heating.

[@EthanNeal]

I actually live in the Upper Snake River Valley, I can attest it gets bitterly cold here in winter. It doesn't help that the main wind direction is SW to NE, the same direction the valley is oriented, so cold air just pools up on the valley floor in places like Rexburg and St. Anthony, since it can't easily be pushed uphill. The sun, quite literally, has to bake the cold away, not an easy task when there's also several feet of snow accumulation every winter.

[@nixnox4852]

I work in agriculture, and going to an hour long "class" for license credit on how frost forms and ways to mitigate it remains one of my favorite that I ever attended. If you drive by orchards (like blueberries) and see short bladed windmills throughout it, those are powered fans that pull the higher warm air down into the orchard, disturbing the pool of cold air and stopping frost. The downside is they can be noisy. There's also variant that's basically a large ground fan pointed straight up, which "drains" the cold air by shooting it up. Apparently despite what you may think, the cold air doesn't really fall back down.

[@Sumurasia]

I once experienced this on a miniature scale! It was a very warm summer here in Finland, so I thought nothing much when I went to an outdoors festival-type event and packed only my summer sleeping bag. However, what I wasn't aware was that the sleeping arrangement was an a smaller open field in the middle of a few rocky hills. All the cold air descended into this miniature frost hollow. I've never felt so cold in my life! I kept praying for morning every minute of it, and I have slept in subzero temperatures before! It was an absolute nightmare of an experience, haha. The next night I slept up the hill.

[@hgbugalou]

Dude I am hooked already. I love this kind of Earth science content.

[@isimerias]

Ok so, I know I’m pretty late to this party. But, this phenomenon actually exists on a massive scale in the Canadian Shield. The low altitude hills and deranged river and lake systems create the perfect conditions for cold air to get trapped in valleys, which helps explain why in the Canadian Shield, maples dominate on hilltops and conifers dominate the cold water logged valleys

[@TheRyansLion]

There are quite a few places in Colorado with temperature inversions. Pretty neat to see when skiing and the temperature goes up at the top of the mountain

[@altitudeiseverything3163]

Yes… During the most bitterly cold days of the winter, my home -at nearly 9,000 ft elevation- is always 5-10 degrees *warmer* than the front range city below. I know to stay home on those days! Winter is longer up here, but we’re spared both the summer heat *and* the most extreme of the winter cold: win, win!

[@totrigo6834]

One shortcoming of the video: he didn't mention the terms "temparature inversion" (or thermal inversion) a single time, which were probably the most important words to teach about this phenomena.

[@trevettekuester4930]

Peter Sinks, Utah mentioned. I was lucky enough to study soil samples from that exact formation.

[@Cesar-qk1rm]

I clicked on this video because the thumbnail remembered me about an Easter Egg in Red Dead Redemption 2. I was really not expecting to see such an well explained video about a topic that I've never heard about before. Believe it or not I was already planning on going camping in the wild next month, so thank you for the information @casualearth.

[@chir0pter]

The interesting thing about these endorheic basins in the Mountain West is how old they are. The western North American cordillera has been uplifting and producing poorly integrated drainages for a long time. The Green River Formation must likewise have been at high altitude, since that's generally a requirement of endorheic basins, and even thought it was subtropical, in the midst of Eocene warmth, it still had some deciduous species bordering it. So basically it represents a small relict of the Western Interior Seaway that had receded millions of years prior, but isolated and uplifted to the sky, with left-behind marine species like stingrays surviving in the alternately freshening and salting endorheic waters trapped by Cenozoic uplift

[@SportyMabamba]

Now I want to see alpine stingrays frolicking in icy mountain rivers

[@chir0pter]

@@SportyMabamba they weren't icey back then

[@SportyMabamba]

@@chir0pter understood, I still want to see sting rays making natural antifreeze and dodging icebergs

[@Ioun267]

I wonder if I may have experienced a manmade version of this effect as a boy when at a Boy Scout event camping in the middle of the Talladega Speedway, where the track and stands form a complete bowl. That night seemed excruciatingly cold and our tents had icicles that morning until the sun got high enough.

[@MatFarringtonInfo]

Great info. I live near the Aranda Frost Hollow in the ACT, Australia. The hollow is encircled by snowgums - a species usually found at much higher elevations.

[@matthewpapa5529]

As a weather nerd, I'm gratified to have a job where I work in the only polje in my home country, connected to the coast by a deep valley. During winter in clear, settled weather, no sun at all makes it into this valley, and I'm continually amazed at the heavy frost and cold fog that remains there all day, just a few kilometres inland from a coast where temperatures have never fallen below freezing. Limestone geology certainly does make for some fascinating meteorological phenomenons.

[@somesortofdeliciousbiscuit3704]

I've noticed this on a smaller scale - used to live at the bottom of a hill and in winter would walk uphill to school - often walking out of a well-defined 'mist hole' such I could see my shadow on the top of the fog. Also there is a 'frost pool' on my way to work since I cross a small depression around a stream - on calm days in spring and autumn I have noticed a distinct temperature rise going up the hill next to the frost pool.

[@donscheid97]

I guess I'm not curious enough to have noticed in all my years of camping or traveling, but many of my experiences now make more sense. I just wrote them off as micro-climate variations, which they were, but no explanation until now.

[@KarlBonner1982]

The Sunset Garden Book has long understood the Central Valley frost hollow in California, and actually created two separate gardening zones (called 8 and 9) based on this fact. These are not the same as hardiness zones, as they take rainfall, summer temperatures, and spring/fall frost dates into account.

[@ThatSB]

Of course california would have specified gardening zones

[@MrSoopSA]

@@ThatSBThey are federally USDA rated and regulated zones, not state regulated 🙄

[@ralphlindberg1299]

FYI, the cold spot in Montana may be near Rogers Pass, but the actual recording station was also in a small sink

[@casualearth-dandavis]

Interesting, thanks.

[@S9999Frank]

We have a local valley near where I live in Norway, which is called the Ice-valley (Isdal in Norwegian). A valley with peaks on both sides, and a place where the sun goes quickly down due to angle of valley. A lake in the middle, so not possible to camp at the coldest spot, but still, if one is out in nature a lot one really notice how geography influences the temperatures. The cold air coming down the mountainsides, and equally opposite on mountainsides that are turned into the sun, with heat coming up the sides in the summer.

[@TERRY-cb2ku]

I live in West Virginia between two steep hills. One hill gets sun nearly all day and the other hill, the side I live on, only gets sun from about 10:30 in the morning until about 7pm in the summer. It progressively gets less and less as fall approaches. For three months out of the year I get no sun at all. One hill will be sunny and dry but the one I live on will have a foot of snow and very cold in the winter.

[@razorel]

That was a fascinating video. I look forward to many more from you

[@BltchErica]

I saw this a week ago in a clearing valley, all of the plants there were frozen white and it was freezing cold, while the rest of the mountain was warm, it looked magical

[@rinima858]

This can also happen to warmer temperatures in smaller geological features. I live in a house on top of a hill, one winter when the temperature was around 2-3C, I visited a house at the bottom of the same hill and found frost on my car when I left. The elevation was less than 100 meters.

[@Dnbootin]

Great video, this is exactly how I wish all informative videos were. Plain presentation, but a tight script with very little repetition or down time, and plenty of great visuals that match what you’re talking about. Good work, and it was wild as hell to find out the second lowest temp ever recorded was done so in a cold hole in UTAH! I was thinking about Utah/NM during the whole video up to that point because I was thinking of how I have been to the mountains dozens of times, but the most bitter cold I’ve ever experienced was in low lying desert areas

[@brianacuff274]

So this is what's happening on my commute to work. I ride a scooter to work in from downtown Seattle to a neighborhood called Lake City - which is in a large depression like this. And I noticed at the top of the hill I'm dressed plenty warm but once I get down into Lake City, I'm freezing. I mean 10 to 15 degrees colder. Nothing like these extremes but immediately noticable and annoying. I'm in the habit now of dressing too warm for the first 8 miles of the 11 mile commute.

[@Magnymbus]

This explains why my dad always insisted on pitching the tent where the low canopy of pine trees is high enough that you can't touch the lowest major branch without jumping, and always on the most convex slope he could find. He would clear the area of anything flammable so there was a roughly 6 foot buffer of bare earth around the fire pit, he would lay down to use his body as a measuring tool. The tent would always twice that distance from the pit. He would make a bed of leaves/pine needles where he was going to pitch the tent to soften where we slept. Most of what he did made sense to me, but the slope and tree height thing always seemed a bit silly. It's fascinating to learn where that tradition might have come from.

[@casualearth-dandavis]

Yes, and the pine needles he put down were important too. It made the spot comfortable, but it also prevented you from losing lots of heat via conduction to the cold earth below.

[@brianevans5616]

Very well put together and presented. I've watched hundreds of documentaries and this is in my opinion is one of the best. Well done sir.

[@FRAYHOLE501]

Odd geography at 0:18

[@shanemadejthedemon8951]

Very odd indeed

[@Cam-nq8br]

Accurate

[@alexclairmont]

youtube algorithm you've done it again! glad to see this video gain traction two years later cus it's really deserved. really enjoyed this video and can't wait to go through all your other videos

[@PinkFZeppelin]

We have a lot of these where I live near Wenatchee Washington. It’s also where most of the world’s apples are grown. The farmers counter this effect by having giant fans on poles in the orchards. They keep the air circulating to prevent frost on the apples in late summer. If the apples frost it will damage the texture of the fruit.

[@blakespower]

this makes sense, my house is at a low point in a hilly area, its always colder in the winter I always have to scrape frost off my windshield in the winter while other people get barely any

[@Amanda-C.]

Could that be just because you get full sunlight later in the day? Even when the sun's well and truly up, I've seen frost lingering in shadows for a good long time.

[@voidhumor2740]

>click on video about microclimates "why did the nazis drive military vehicles to a random hole in the Austrian woods

[@annaczgli2983]

I just discovered your channel, & am glad I did. I like the unusual, counter-intuitive subject matter, & your calm, & matter-of-fact delivery. Thanks for this video. Looking forward to more videos.

[@nobodyspecial9035]

Explains why some of my end of summer, overnight, motorcycle expeditions in Nevada were so incredibly cold. Contrasty, sometimes you hit abnormally warm sections too.

[@ilikequiet6474]

Interesting. Your delivery was perfect, pausing just briefly before beginning again. Have never heard this done before on YT presenters just rush their delivery and burying us in words wIth out time to digest what was said. Thanks

[@AZ-su1zg]

Now that I think about it, the times I’ve been the coldest were in camping in a depression/valley. I’m curious if that’s the same as a hole in this sense. I was literally so cold in one of the loop trails in snowmass villages i gauged my chance for survival based on another camper being in the area. I usually prefer valleys because it feels less scary when I have to pee in the middle of the night lol.

[@Psyda]

Good stuff dude. Keep up this quality and you'll go far.

[@rushi5638]

I mean this as purely constructive criticism but a tiny bit of work on a couple things could net a huge improvement. A couple of flubbed line reads and audible inhales here, for which a second take and a bit of editing would not go amiss. Still a great vid, just saying that on a technical and vibes level this sounds like an impromptu recording of a lecture given by a new-but-passionate TA. Hope quality goes up, but I'm not going to complain so long as the subject matter stays interesting. 😅

[@ASelbo]

This also explains what happened to the (now enshrouded in conspiracy theories) Dyatlov Pass expedition. Where a group of well trained students, led by an experienced guide, died "mysteriously" during a cold winter night. This well known cold effect combined with over-exertion of the expedition members, sweaty clothes, too late setting of camp and no dry spare clothing finally leading to the death of all the expedition members. The rescue party found some of the dead bodies almost naked and away from camp. Theory persist that they had tried to escape some kind of horror. In this case the horror was hypothermia caused by lack of knowledge of this fact and preparation to avoid consequences.

[@Avaricosity]

If you're interested in a really good video on the subject, Lemmino has a wonderful video essay on it. There's some neat details he gets into that most documentaries don't.

[@firefox5926]

5:11 surprised we haven't taken advantage of this phenomena to make cold storage basins makes me wonder how cold the bottom of an open cast mine in one of these areas could get

[@jasonbrewer6714]

I'm from Montana and learned this the hard way while in boy scouts. Our scout leaders had us build overnight camps in the winter, we thought it a great idea to do it in a between two rocky hills. it was made all the worse by making the shelter in a recess we dug out more. Coldest I've ever been in my life.

[@r0cketplumber]

My parents built their retirement home at 8900 feet near Lake George, Colorado which is lower down at 8000 feet. At the house it could get down to -35F, but in Lake George it was below -50F the same night. My folks are long gone and I live in Florida now, I've had enough of that miserable cold. At this moment on New Year's Eve it is 66F and sunny, I think I'll step outside and catch some rays :)

[@alexmarquardt5370]

1:46 doo doo

[@Xooteryt]

3:33 doo doo

[@LauraMLane]

That was really neat, thank you! I subscribed immediately.

[@renan_raul]

I had never camped in a lower terrain just for the fact that if it rains, the water would not flood my tent. Bur this is a new piece of information that I would’ve never imagined.

[@ranjapi693]

Where I live, we got two mountain Ranges enclosing the area. We sit on the Lee side, where the wind gusts warm up. But we got a big lake that warms up During summer that sits in a long valley, and when the surrounding air gets colder in winter, you got a sheet of fog above the valley for months.

[@bathbomber]

Now I'm worrying what kind of crazy combination of physics and geography would be required for an ice oasis (like in The Last Airbender) to exist in the real world.

[@awes4376]

Really interesting video!!! and thanks for using celsius

[@aedan_s]

Great video! I love geography and I had never heard of this. I definetly want to learn more from you - subscribed :)

[@davidpaylor5666]

I live in the UK and we don't get quite such extremes as you do in the States but I lived in a village that was at the head of a valley. In Winter if you lived on the top of the slopes it would be 10C warmer in the morning than in the middle of town, down by the river, and on a still day it would stay that way all day. You could be frost-free outside your house but drive downhill into town and your car will ice up as you drive along.

[@Melody_Raventress]

I don't know if you're getting an algorithm bump, but your video just popped in my rec list. A very interesting phenomenon that is completely new to me. I enjoyed, you've got a sub.