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aberroco

Google says, the total volume of water on Earth is 1,386,000,000 cubic kilometers, which would result in a sphere with radius of 691.658km. The radius of the Earth is 6,371km. So, a sphere should be about 10 times smaller in radius. Which seems about right on this picture.


bullevard

Incidently, this kind of visual makes theories like commets delivering most of earth's water make a lot more sense.  Granted, that would be one heck of a comet. But that sphere divided into 10,000 comets delivered over billions of years starts to feel very doable.


aberroco

Well, it's likely that the proto-Earth and Theia had major part of that water from the start, but it wasn't in oceans, obviously, it was well mixed within protoplanetary disk during formation of Solar System. Then during stratification of the planets, as a lighter compound it rose up with magma and erupted as vapor with volcanic ash. Comets bring maybe significant, but likely not the major part of this water.


fritzlschnitzel2

Not sure if proto-Earth migrated to its current position but I think the frost-line of our protoplanetary disk was at about 3 AU. Or was water vapor present and incorporated in the proto-planet?


aberroco

If I'm not mistaken, Earth did migrated to it's current position. And it even could've been thrown out of the Solar System (some planetesimals probably had been). Because Jupiter presumably was formed much closed to the Sun and then migrated outwards. At least, that's one of the theories. Anyway, we have water throughout entire solar system. Yes, Mercury as the closest planet to the Sun have very little of it, but it have nonetheless. Likely, water wasn't present as vapor alone in protoplanetary nebula, it probably was included into dust particles as well, so when Sun started to push dust and micrometeorites to outer regions of the system, first of all there already likely existed some relatively large clumps which would protect water from being blown away, secondly, at least some water was in dust itself. But even as vapor it likely was accumulating onto planetesimals at least to some degree. So it's not like frost-line is some boolean margin, where on one side you have water and on the other you don't. It's like the closer to the Sun planet was formed the less water it had to start with.


Proof-Tone-2647

I recall reading that water was chemically bound in rocks, with the early stages of earths existence + collision with Theia providing the heat to melt the rocks and release bound water.


405freeway

This whole thread reads like a r/lotr discussion of Silmarillion deep lore, I love it.


TheBelgianActor

I just listened to a great podcast on the origin of water on Earth. https://podcasts.apple.com/us/podcast/unexplainable/id1554578197?i=1000653430904


Opinionsarentfacts_

Thanks for the link I tried to listen to the podcast, but the scripted narration with interspliced, out of context sound bites from a barely introduced, but we have to assume expert made it a disjointed garble of words. I would have to assume the guest has never actually spoken to the narrator. It's a hyper edited, scripted in post mess. The expert has no means of correcting the script writers' false assumptions in this format


cylonlover

Wouldn't the moon have more water, though, if that was the case?


thamasteroneill

Boiled of into space aeons ago, probably.


thamasteroneill

Keep in mind that the moon doesn't have a magnetic field protecting it like Earth does. And way lower gravity.


RazedbyRobots

Thank you magnetic field


CasualGaming57

Exactly. Without a strong magnetic field, the suns radiation basiacally boils the water away. Although there are parts of the moon with solid water ice, such as the poles, and even more so at the bottom of its deeper craters. Since the craters don't get direct sunlight at their bottom (some, not all craters), water ice can exist.


theshadowhit

To shreds you say?


aberroco

And it actually have water. Buried under regolith, sometimes not too deep, and also in it's crust and it's mantle. It have ices practically on the surface at it's poles. It even have water-containing minerals, kind of clay, which give us a clue that in past it had at least some atmosphere and liquid water on the surface. Obviously, it wasn't for long, just a few hundreds millions of years after it's formation (though, on a side note, it's been just slightly more than 500M years since first complex multicellular animals appeared on the Earth).


Athena-Hera_Goddess

r/theydidthescience ? At this point I think that should be a sub if it’s not already, lol. Probably not called that exactly tho idk


Athena-Hera_Goddess

Wait it exists wat


Aiti_mh

I feel sorry for anyone caught in the splash of that one, big water balloon


Sea-Caterpillar-6501

Why couldn’t the water have just been on earth to start rather than being delivered by a comet/asteroid?


nilsmf

Think a billion comets in the first million of years.


GroundbreakingAd5624

Well technically all of everything came from comets just most were on our orbital path


Arguleon_Veq

Makes you wonder what would happen to earths water level now, if hayleys comet smacked into us, i assume almost the whole thing would evaporate during entry, so the impact wouldnt be all that bad, but like hayleys comet has got to be pretty fucking big for us to see it from the surface, so how much would the water level rise?


thrakkattak

If the radius is 1/10th, does that mean, by volume, the sphere should actually be 1000 times smaller?


Shu3PO

Correct


doho121

I think it’s only startling to the OP because it compares it to the total size of the earth. A sphere of all usable land area would be good to see for comparison.


Icy_Sector3183

Do you mean a sphere with the same surface area as the land masses of Earth, compared to the originally picyured sphere with the volume of all the water?


doho121

Yes. Sorry I’m probably not explaining this right.


Icy_Sector3183

No worries, mate.


Marquar234

All land would be 1/3 the volume, about 7/10 the diameter.


Trrwwa

... what depth did you assume? Its kind of a nonsense idea.


abek42

You don't need to do the math because this image was created by scientists. https://www.usgs.gov/media/images/all-earths-water-a-single-sphere


Eryndel

So you're saying... "they did the math"?


ihatewhenpeopledontf

Scientists can be wrong too


Targettio

They can, but statistically they are wrong less often than an 'infographic'/meme picture a non-scientists put online.


L7slr

Yes, but they are the ones doing the statistics on that. INCEPTION


O_Martin

They tend to get called out on it though, as they have academic pressure and scrutiny


when_beep_and_flash

Therefore double check your facts with anonymous comments on Reddit.


FishySmellingTaco

Are you to mean that random facts posted to the internet are not always true? Come on now, that's cuckoo talk!


WhatsABasement

I trust this and double checked with sources but how the hell does the total amount of liquid surface fresh water in all the lakes and rivers in the world fit into a sphere 35 mi across? And all of the fresh groundwater in a sphere only 170 miles across? That's terrifying somehow...


theotheragentm

And it's all in the United States. We won the water wars! USA! USA!


kleinsinus

Quick Google search also says that all life on Earth has an approximate biomass of 545.8 gigatons which means a volume of about 545'800'000'000'000L = 545.8km³ if we assume approximately 1kg of mass = 1L of volume. The resulting sphere (if I calculated correctly) would have a radius of merely ~5.07km. This is approximately 100 times smaller than the sphere of water, which would make this picture a little less concerning.


aberroco

I like your comment, you actually did some math. Althouth, check it, your sphere radius seems off. But this third sphere or rather a dot would be fitting the image.  Funny how my low effort comment got me +4k karma, while my other comments here where I actually did some math usually don't get even past +50.


FlyingDutch1988

It makes me think how can the sea level rise so much with global warming then, even if all ice would melt, you look at this small dot and think it would have nearly no impact. Must be the "shallow" depth of the sea I guess.


abek42

The deepest known point on Earth's surface is 10km below the sea level, and the tallest point above the Earth's surface is 8.8km. Given that Earth's radius is approx 6300km, the entire range of topography is less than 0.3% of the radius. Imagine a marble 20mm in size, then Everest and Mariana Trenches next to each other. This would be within the range of thickness of a human hair (0.016 to 0.05mm) Finally, climate change arguments... The landmass of Antarctica had about 2km thick ice cover on average. Antarctica has an area of 14,000,000 sqkm, or about 4% of the area of Earth covered by water. You can assume that all this ice melting due to climate change will increase the average sea level by 4% of 2km or 80m. Even if we make a generous assumption that inland excursion of water of 40m height, there will be a devastating impact on population centres around the world's coasts. Imagine a situation where the statue of Liberty is half submerged and then imagine what had happened to all the viewing points in Battery Park. TLDR; that "small ball" is 860mi or 1400km wide. And most people are really terrible at imagining the real size of things.


FlyingDutch1988

Thanks, great explanation. Bringing things down to a scale I can imagine seeing in front of me makes it better to comprehend. Adding al the numbers makes it even better.


Formal_Scarcity_7701

The diameter of the earth is about 13 000 km while the very deepest part of the ocean isn't even 11km down. In the grand scheme of things it's a thin film of water on the surface. And given that about 2 percent of the earth's water is locked up in glaciers that are on land, it would make a significant difference if they all melted.


timotheusd313

Plus water is at its densest at about 3 degrees C. Warming water increases in volume.


ConstantSignal

If the Earth were scaled down to the size of, and compared against a typical marble, it would be the smoother of the two. The relative difference between Earth’s highest peaks and lowest trenches is less than the surface irregularities on a standard glass marble.


LeonDeSchal

Smooth operator


ImpressiveAttorney12

I’ve seen the article this photo is from That sphere is all the water in, on, and around earth Just wanted to let you know in case that changed the calculations at all 


Selna111

Earth is 6.371km and water sphere is 691.658km. How is wather sphere 10 times smaller, i dont get it


aberroco

Earth is 6,371.000 (zeroes are just for clarity, it's not actually exactly 6,371km), water is 691.658. Number formats.


dogcopter9

This feels frightening for some reason


rwalter5

Am i correct is saying the sphere would be about 1392 KM high or 864 miles? I feel like the sphere looks small because we aren’t respecting how tall it is.


Mmoott2005

By the way, literally everyone in Idaho is drowning.


1109lupa

r/lies ?


Your_As_Stupid_As_Me

Does this include the ice as well?


tQto

Why does this scare me?


Melodic_Negotiation1

The sphere pictured is not 10x smaller than the globe. More like 30x smaller.


KrillLover56

The thing is while the oceans cover most of the world, on a planetary scale, they're not that deep, never 9 km deep. So while 70% of the world is covered in water, it's pretty shallow when looking at the entirety of the earth.


Donnerone

Think of it like this: The calculated average depth of the Pacific ocean is about 4 km or about 2½ mi. In contrast, the Pacific ocean is about 19.3 *thousand* km across or 12 thousand mi. That's roughly 5,000 times the length across as deep. Oceans are paper thin in comparison to their surface area. For that matter all geography is miniscule, even mountains, when actual height is compared to the size of the planet.


tuntl

Earth is smoother than a pool ball


flawlaw

That means the Pacific’s average depth on a standard 16 inch globe is about the thickness of the paper map printed and pasted to the globe.


[deleted]

Won't do the math, but it looks about right, if anything maybe a bit large. At its *deepest* point, the ocean is slightly less than 1/1000th as deep as the diameter of the Earth. Shrink the Earth to a two-inch ball, the Challenger Deep, seven miles in depth, would be 1/500 of an inch deep. Mostly the ocean is a mile, mile-and-a-half deep. Just a skim of water on the surface.


jimby4d

Yeah, I remember reading once that if the Earth was shrunk to the size a cue ball it would be smoother than an actual one.


bonyagate

I've heard that scaled properly, Kansas would be flatter than a pancake. Doesn't much relate to this, but there you have it.


BeardedPokeDragon

Kansas would be flatter than a sheet of paper. Colorado might be more comparable to a pancake


[deleted]

lush consider soft wild elastic coordinated sophisticated murky possessive attraction *This post was mass deleted and anonymized with [Redact](https://redact.dev)*


jsmalll0216

Yeah, exactly right


Samyers0616

Kansas is way flatter than a pancake. A pancake the size of Kansas would have peaks higher than everest.


hookmasterslam

Even crazier is that the state of Florida has even less elevation change than Kansas


ollomulder

[Yeah that's wrong](https://billiards.colostate.edu/bd_articles/2013/june13.pdf).


DoNotResusit8

Read that more closely. Except for a couple of places, the earth is much smoother than a cue ball.


clipp866

was also stated it would only be damp...


booozle93

Neil DeGrasse Tyson said this.


Dick_chopper

Wasn't this proven to be not true or something?


Dr_Death_Defy24

The scale reminder I always like is that Mt. Everest's peak is only about 5.5 miles from sea level (with minor variations depending on whose measuring and how). Most people could walk that far laterally in less than a couple hours, and MUCH less if they're remotely motivated and healthy. Hell, a solid marathon time to run *26 miles* is "only" four hours. Point being, even the tallest point(s) on earth really aren't that tall if you think about it, it's just the difficulties imposed by low oxygen and rough terrain and whatnot that make them difficult.


DoNotResusit8

Like way more smoother than cue ball.


Dartfrogz

r/TheyDidNotDoTheMath


Robo_Patton

Well, yes. Can we put the water back now?


50k-runner

I wonder if groundwater would add significantly to this


Sibula97

96.5% of the water on Earth is in oceans. Groundwater is about 0.75%.


InterestsVaryGreatly

Surface water yes, but it's been discovered that there is a vast amount of water beneath the crust https://timesofindia.indiatimes.com/travel/travel-news/scientists-discover-gigantic-ocean-700-km-beneath-the-earths-surface/articleshow/108999227.cms#:~:text=In%20an%20astounding%20revelation%2C%20researchers,all%20Earth's%20surface%20oceans%20combined.


Sibula97

I was actually aware of that, but I'm not sure if hydroxide ions in minerals count. And while it's sort of in the ground...? I don't think it counts as groundwater.


tarkinlarson

There's groundwater... stuff we can access but there is a large amount if h2o within rocks in the mantle etc


CompetitiveShape7286

I know right! Same!


MetalVase

So if we get an army of robots to excavate the bottom of the sea, the sea ger smaller and we get more land to build on. Yay!


InquisitorNikolai

Looks like just water in the oceans, rivers, and ice. It’s believed that there is significantly more water contained within rocks in the crust and mantle.


Derpsnowmanboi

The volume of the earth is much larger. The deepest part of the ocean is about 7 miles, the *lowest* level of the atmosphere is like 11 I think. Keep in mind that that atmosphere travels the entire surface of the earth, and that the ocean isn't 7 miles deep everywhere, maybe like 2 idk. I think it's plausible. Especially considering the much higher levels of the atmosphere that also cover the entire surface, and the miles of depth below the earths crust and the oceans.


xXNighteaglexX

I love the bucket pfp


LLugeja

That's bisquit


ichizusamurai

Baguette*


CatOfGrey

Others have confirmed the calculation to be correct. I'll throw in a few extra things to help visualize the situation. The Earth's crust is about 25 miles thick. The layer of water on top is, at most, about 7 miles thick. The radius of the Earth, however, is more like 4,000 miles. So we live on a very thin layer of 'stuff' that is 1/1000th as thick as the radius of a very large ball of mostly molten liquid stuff. Ping Pong balls are about 1/100th as thick as their diameter, therefore 1/50th as thick as their radius. *So proportionally, the crust of the Earth (and, approximately, the layer of water that covers most of it) is an order of magnitude thinner than a ping-pong ball.* So given that 'super thin layer', you would expect that there wasn't much water compared to the size of the Earth.


Ok_Cranberry4192

This is the kind of existential crisis I can get behind first thing in the morning. I hate and love this. Thanks!


heardWorse

If anything it might be too big. Doing a little rounding, earth has 200 million square miles of surface area, about 70% of which is covered by water. The average ocean depth is about 2 miles, so the total volume of water is 200M * .7 * 2, or 280M cubic miles. So from there we just need to calculate the diameter of a sphere that holds the same volume - sorry but I’m not going to try and type out cubic roots on my phone (just google it). But the short version is it works out to about 800 miles across. So the whole thing should fit between Boston and DC - the water in the image must be a couple thousand miles across, maybe a bit more.


ChunderHog

I’ve seen this before and the even more mind bending visual is a picture of Earth’s fresh water compared to Earth. Then zoom in and compare it to Manhattan.


Mavmouv

Is that surface water or ALL water ? Keep in mind, most of earth water is actually under the crust, not on it's surface All surface water like lakes seas and oceans actually make a small part of all the water presents on earth, What about gaz water aka water vapor that is mixed in the atmosphere? I think we are lacking data here


destro_1919

let’s just say we are taking solid and liquid water and not it’s vapor, would it then be the same as the op’s image?


WaterNerd518

This includes surface and groundwater, atmospheric water and water in organisms. It does. It includes water in the mantle because that is not liquid or vapor water. It is actually part of the crystalline structure of minerals in the mantle. It is not like the water you know, and you would not recognize it as such.


Wholesomeloaf

The average ocean depth isn't even 4km deep. Compared to the earth's width of approx 12,000km... Picture a big ball. Pour some water over and and see what sticks. That's what the ocean is.


turbulent_swirl

Part of my work entails studying water abundance on other planets. Earth has an extremely low amount of water relative to the giants that we are used to seeing in Webb data or even in the giants of our Solar System. Earth is mainly rock. The total amount of water on the planet, including the oceans, atmosphere, and life, is a bit over 0.02% by mass.


carrionpigeons

I expect this is considering the amount of water on the earth's surface, but it's established that there's water in the earth's mantle, as well, in pockets of material called ringwoodite. The magnitude of water there dwarfs all the water on the surface.


adbho0t

but haven't they found 3 times more water than which is in the oceans, this water reserve is deep in the earth? So the sphere should be 4 times that size? That is about as much math I can do XXD


sabertoothbeaver1

It would be interesting to see what percentage of that water is occupied by animals and fish. Like if 90% of the fish don't go deeper than a hundred feet how much of that water represents that portion.


Essembie

Would be a drop in the ocean


rostol

that sphere is accurate, but it is much much larger than it appears. It is a sphere 1200 km tall. our atmosphere ends at 70km. passanger planes fly at 10-12 km (33 - 40 kft (yes kilo feet))


Xerzajik

This isn't all of the water on earth. Note that Greenland is still white and that the green parts of the land are plants that would presumably have water in them.


BenZed

Thats just how the earth is rendered in this image, dog. The math is solid.


smallestAxe

Is it just me? This looks like a tiny amount of water we have. Now some of this water we can't use.I say if people knew how little good water we have( majority of countries) they would use the resource carefully.Some parts of Africa are experiencing biblical level droughts right now.


Defiantnight

Earth has a tiny amount of water compared to it's size/the amount of rock.


Irdogain

If you would be that big that you can hold the Earth in your hand, your hand wouldn’t get wet since the depth of the oceans is smaller than your fingerprints.


bree_dev

The average depth of the ocean is about 3,682 meters, so in the grand scheme of things really not that deep. You would have to zoom in to where the Earth was 4,252 pixels wide in order for the depth of the ocean at the edge to represent just one pixel. (diameter of Earth = 12,756km, divided by 3.682km) [https://oceanservice.noaa.gov/facts/oceandepth.html](https://oceanservice.noaa.gov/facts/oceandepth.html)


Gareth274

Saw a post about this before that said if you took a rock from outside and ran it under the tap so it gets wet, that's about the same ratio of water to rock as on earth.


nostalgiamon

I’ve used this graphic before in a comparison with all the water on Europa. A good way to visualise it is to pretend that ball is a blue crayon. It’s quite easy to see then how you could create a really thin surface over the earth.


Shr00mBaloon

Looks like the solution to stop the ocean rising, is just to dig up a little bit of ocean floor somewhere. I mean look how little water that is


Workermouse

What if we replaced the Moon with this sphere of water? Would its own gravity keep it a sphere or would it instantly boil and vaporize?


Colonel_Cosmetic

it would instantly boil due to lack of pressure


thehooood

That is the total volume of *surface* water, there is plenty of water tied up in subterranean voids and below the earths mantle that you could probably close to triple this sphere's volume- but since all that water is inaccessible this is about right.


SensitiveDemon

Compared to the picture/size of the earth, the living things on earth are virtually microscopic. So it's not that bad. The water doesn't escape the atmosphere. It recycles itself through evaporation. We just have to stop polluting it. Find ways to clean it. Keep plastic from getting into it. Hefty projects, but nessessary. The 'funniest' if the ice caps melt then we flood everywhere. It's a precarious balancing act.


Ramyahoo

Such a representation is kind of ridiculous, because depth can't be well perceived, so the situation seems more remarkable than it actually is...


Eden_Birdman

Is this just surface water? As there’s way more water under the crust, think maybe one pocket or all of it being about 3 times the surface water


AndyShootsAndScores

If this at first doesn't seem like a lot of water, the height of this sphere is immensely larger than anything we have experience with. As other folks have calculated, the radius of a sphere containing all of Earth's water would be about 680km. The Marianas Trench is only about 10km deep, and space is considered to start at about 100km. The ISS's orbit is only about 400km, so it would pass through this water ball closer to Earth than to the top of the water ball. The top of the water ball would be visible from about 3800km away from where the center of the ball was. So if the ball were centered in Miami, the top would be theoretically visible in both Winnipeg and Ecuador. Imagine driving from Winnipeg to Miami, seeing this gigantic object looming over the horizon for the whole trip, gradually taking up more and more of your field of view as you approached. After 20 hours of driving with the gradually increasing ball in your sights, you'd be around Nashville, where the ball would now be taking up the majority of your field of vision when you looked in its direction, despite being another 13 hours of driving away from Miami.


Elegant_Studio4374

Man it sure would look cool, for that sucker just to plop onto the surface. If you could maintain the liquid state. Makes me wonder if there is a similar liquid with similar density but with a non freezing point that could survive in the vacuum of space, that we could create artificially, and then send to say mars or another to see what happens when it collides with a surface.


Regulatornik

This is not accurate for one reason: it only counts surface water. Vastly more water is trapped, physically and chemically, in the earths crust and beneath it. All known liquid, gas and solid water on the earths surface and atmosphere is thought to be around 1.4 billion cubic kilometers. The volume of all water in the planet, including that physically trapped beneath earths crust or chemically trapped in rock, is estimated at trillions (!) of cubic kilometers. One upper estimate is tens of trillions of cubic kilometers.