# Why doesn't water cover the entire surface of Earth? **URL:** \ **Category:** Miscellaneous and Personal Stuff I Must Share\ **Created:** [August 20, 2023, 12:30am UTC](https://boards.straightdope.com/t/why-doesnt-water-cover-the-entire-surface-of-earth/988810 "2023-08-20T00:30:08Z")\ **Posts on this page:** 20\ **Page:** 1
**Author:** ![HoneyBadgerDC](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/honeybadgerdc/32/1033_2.png) [@HoneyBadgerDC](https://boards.straightdope.com/u/HoneyBadgerDC)\ **Post date:** [August 20, 2023, 12:30am UTC](https://boards.straightdope.com/t/why-doesnt-water-cover-the-entire-surface-of-earth/988810/1 "2023-08-20T00:30:08Z")
It seems odd that with the massive amount of water we have on this planet that it just doesn’t cover the entire surface. Is there some physical reason that causes a certain amount of land to rise above the water? Is it because of the massive amount of force that water is able to exert on the plates? ---
**Author:** ![Beckdawrek](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/beckdawrek/32/3647_2.png) [@Beckdawrek](https://boards.straightdope.com/u/Beckdawrek)\ **Post date:** [August 20, 2023, 12:32am UTC](https://boards.straightdope.com/t/why-doesnt-water-cover-the-entire-surface-of-earth/988810/2 "2023-08-20T00:32:40Z")
Umm. Gravity ---
**Author:** ![Darren\_Garrison](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/darren_garrison/32/92_2.png) [@Darren\_Garrison](https://boards.straightdope.com/u/Darren_Garrison)\ **Post date:** [August 20, 2023, 12:43am UTC](https://boards.straightdope.com/t/why-doesnt-water-cover-the-entire-surface-of-earth/988810/3 "2023-08-20T00:43:39Z")
> [@HoneyBadgerDC](#): > > It seems odd that with the massive amount of water we have on this planet that it just doesn’t cover the entire surface It seems odd to me that this seems odd to you. The reason the water doesn’t cover the entire surface is because there isn’t enough water to cover the entire surface. ---
**Author:** ![beowulff](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/beowulff/32/542_2.png) [@beowulff](https://boards.straightdope.com/u/beowulff)\ **Post date:** [August 20, 2023, 12:47am UTC](https://boards.straightdope.com/t/why-doesnt-water-cover-the-entire-surface-of-earth/988810/4 "2023-08-20T00:47:15Z")
There’s not very much water after all: [All of Earth's water in a single sphere! | U.S. Geological Survey](https://www.usgs.gov/media/images/all-earths-water-a-single-sphere#:~:text=The%20largest%20sphere%20represents%20all,cubic%20kilometers%20(km3))). ---
**Author:** ![HoneyBadgerDC](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/honeybadgerdc/32/1033_2.png) [@HoneyBadgerDC](https://boards.straightdope.com/u/HoneyBadgerDC)\ **Post date:** [August 20, 2023, 12:52am UTC](https://boards.straightdope.com/t/why-doesnt-water-cover-the-entire-surface-of-earth/988810/5 "2023-08-20T00:52:14Z")
> [@Darren\_Garrison](#): > > It seems odd to me that this seems odd to you. The reason the water doesn’t cover the entire surface is because there isn’t enough water to cover the entire surface. There is more than enough if the surface was flatter. I am just wondering if water doesn’t play a bigger part in forming the land masses. ---
**Author:** ![beowulff](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/beowulff/32/542_2.png) [@beowulff](https://boards.straightdope.com/u/beowulff)\ **Post date:** [August 20, 2023, 12:53am UTC](https://boards.straightdope.com/t/why-doesnt-water-cover-the-entire-surface-of-earth/988810/6 "2023-08-20T00:53:42Z")
The Earth is already really, really flat… ---
**Author:** ![HoneyBadgerDC](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/honeybadgerdc/32/1033_2.png) [@HoneyBadgerDC](https://boards.straightdope.com/u/HoneyBadgerDC)\ **Post date:** [August 20, 2023, 12:54am UTC](https://boards.straightdope.com/t/why-doesnt-water-cover-the-entire-surface-of-earth/988810/7 "2023-08-20T00:54:25Z")
Yes it is very flat relative to it’s diameter or mass, very flat actually. ---
**Author:** ![Beckdawrek](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/beckdawrek/32/3647_2.png) [@Beckdawrek](https://boards.straightdope.com/u/Beckdawrek)\ **Post date:** [August 20, 2023, 12:54am UTC](https://boards.straightdope.com/t/why-doesnt-water-cover-the-entire-surface-of-earth/988810/8 "2023-08-20T00:54:44Z")
Umm. Teutonic plates ---
**Author:** ![Darren\_Garrison](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/darren_garrison/32/92_2.png) [@Darren\_Garrison](https://boards.straightdope.com/u/Darren_Garrison)\ **Post date:** [August 20, 2023, 12:57am UTC](https://boards.straightdope.com/t/why-doesnt-water-cover-the-entire-surface-of-earth/988810/9 "2023-08-20T00:57:52Z")
> [@Beckdawrek](#): > > Teutonic plates ??? > **[Teutonic Plates (Published 2007)](https://www.nytimes.com/2007/11/18/travel/tmagazine/14well-germany-t.html)** > > Move over, Spain. The latest culinary trail leads to Germany— and it’s not your mother’s blutwurst anymore. ---
**Author:** ![HoneyBadgerDC](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/honeybadgerdc/32/1033_2.png) [@HoneyBadgerDC](https://boards.straightdope.com/u/HoneyBadgerDC)\ **Post date:** [August 20, 2023, 12:58am UTC](https://boards.straightdope.com/t/why-doesnt-water-cover-the-entire-surface-of-earth/988810/10 "2023-08-20T00:58:43Z")
I have no idea why this question suddenly popped up in my head as I have never even given it a thought before. I wish I could identify my question better. ---
**Author:** ![Beckdawrek](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/beckdawrek/32/3647_2.png) [@Beckdawrek](https://boards.straightdope.com/u/Beckdawrek)\ **Post date:** [August 20, 2023, 1:01am UTC](https://boards.straightdope.com/t/why-doesnt-water-cover-the-entire-surface-of-earth/988810/11 "2023-08-20T01:01:23Z")
Yeah, those. Good an answer as any. 😊 (Tectonic) ---
**Author:** ![HoneyBadgerDC](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/honeybadgerdc/32/1033_2.png) [@HoneyBadgerDC](https://boards.straightdope.com/u/HoneyBadgerDC)\ **Post date:** [August 20, 2023, 1:05am UTC](https://boards.straightdope.com/t/why-doesnt-water-cover-the-entire-surface-of-earth/988810/12 "2023-08-20T01:05:10Z")
Does water exert downward pressure differently than earth? ---
**Author:** ![Dandan](https://avatars.discourse-cdn.com/v4/letter/d/a87d85/32.png) [@Dandan](https://boards.straightdope.com/u/Dandan)\ **Post date:** [August 20, 2023, 1:05am UTC](https://boards.straightdope.com/t/why-doesnt-water-cover-the-entire-surface-of-earth/988810/13 "2023-08-20T01:05:30Z")
> [@beowulff](#): > > There’s not very much water after all: > [All of Earth’s water in a single sphere! | U.S. Geological Survey](https://www.usgs.gov/media/images/all-earths-water-a-single-sphere#:~:text=The%20largest%20sphere%20represents%20all,cubic%20kilometers%20(km3))). Beowulff, thanks for the groovy link. Have you come across anything to describe the depth of water if the globe was molded to perfect spherical smoothness? A coat of thick paint? Dan ---
**Author:** ![Llama\_Llogophile](https://avatars.discourse-cdn.com/v4/letter/l/49beb7/32.png) [@Llama\_Llogophile](https://boards.straightdope.com/u/Llama_Llogophile)\ **Post date:** [August 20, 2023, 1:09am UTC](https://boards.straightdope.com/t/why-doesnt-water-cover-the-entire-surface-of-earth/988810/14 "2023-08-20T01:09:37Z")
Real estate lobbyists. ---
**Author:** ![Beckdawrek](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/beckdawrek/32/3647_2.png) [@Beckdawrek](https://boards.straightdope.com/u/Beckdawrek)\ **Post date:** [August 20, 2023, 1:10am UTC](https://boards.straightdope.com/t/why-doesnt-water-cover-the-entire-surface-of-earth/988810/15 "2023-08-20T01:10:55Z")
Or maybe Cruise ship lines? Ports of call and all. ---
**Author:** ![HoneyBadgerDC](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/honeybadgerdc/32/1033_2.png) [@HoneyBadgerDC](https://boards.straightdope.com/u/HoneyBadgerDC)\ **Post date:** [August 20, 2023, 1:12am UTC](https://boards.straightdope.com/t/why-doesnt-water-cover-the-entire-surface-of-earth/988810/16 "2023-08-20T01:12:00Z")
> [@Dandan](#): > > Beowulff, thanks for the groovy link. Have you come across anything to describe the depth of water if the globe was molded to perfect spherical smoothness? A coat of thick paint? > > Dan This is exactly what I find so fascinating that relative to the size of the earth these are very tiny amounts. ---
**Author:** ![beowulff](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/beowulff/32/542_2.png) [@beowulff](https://boards.straightdope.com/u/beowulff)\ **Post date:** [August 20, 2023, 1:12am UTC](https://boards.straightdope.com/t/why-doesnt-water-cover-the-entire-surface-of-earth/988810/17 "2023-08-20T01:12:38Z")
It’s been asked before: > Around 2.7km, or 8,860 feet. ---
**Author:** ![Dandan](https://avatars.discourse-cdn.com/v4/letter/d/a87d85/32.png) [@Dandan](https://boards.straightdope.com/u/Dandan)\ **Post date:** [August 20, 2023, 1:21am UTC](https://boards.straightdope.com/t/why-doesnt-water-cover-the-entire-surface-of-earth/988810/18 "2023-08-20T01:21:20Z")
> [@beowulff](#): > > It’s been asked before: > > [geology - If the Earth were a smooth spheroid, how deep would the ocean be? - Earth Science Stack Exchange](https://earthscience.stackexchange.com/questions/7446/if-the-earth-were-a-smooth-spheroid-how-deep-would-the-ocean-be) > > Around 2.7km, or 8,860 feet. Well, not by me, of you. Lazy booger me, could have googled that. Thick coat of paint. Thanks again. Dan ---
**Author:** ![LSLGuy](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/lslguy/32/5813_2.png) [@LSLGuy](https://boards.straightdope.com/u/LSLGuy)\ **Post date:** [August 20, 2023, 1:40am UTC](https://boards.straightdope.com/t/why-doesnt-water-cover-the-entire-surface-of-earth/988810/19 "2023-08-20T01:40:23Z")
The actual answer is plate tectonics and the deep convection driving it. In a nutshell, the forces of separating and colliding plates are strong enough to push the rock surface higher than there’s enough water to cover everything. To some degree, once the plate motion process is producing both high and low spots, the water will tend to collect in the low spots which means the height of the high spots need not be quite so high. There’s no reason in principal that the Earth couldn’t have so much surface water that the mountains were all submerged. But that’s just not the way this planet is equipped. As to the idea of the weight of water flattening things out there are two points to be made: 1. Because the water accumulates in the low spots, the water is pressing down there: on the low spots of the lithosphere. To the degree the surface is plastic, that will push rocks elsewhere up, not down. Toothpaste, meet tube. 2. The density of ordinary rock is ~3 to 6x that of water. Water sitting on rock is heavy, but not nearly as heavy as the rock. Said another way, the main thing pushing the middle of a mountain down is the rock above it. Adding some water isn’t going to do much. ---
**Author:** ![penultima\_thule](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/penultima_thule/32/3833_2.png) [@penultima\_thule](https://boards.straightdope.com/u/penultima_thule)\ **Post date:** [August 20, 2023, 2:01am UTC](https://boards.straightdope.com/t/why-doesnt-water-cover-the-entire-surface-of-earth/988810/20 "2023-08-20T02:01:56Z")
> [@beowulff](#): > > There’s not very much water after all: > [All of Earth's water in a single sphere! | U.S. Geological Survey](https://www.usgs.gov/media/images/all-earths-water-a-single-sphere#:~:text=The%20largest%20sphere%20represents%20all,cubic%20kilometers%20(km3))). Have cited that myself on many occasions. Fantastic. Would have to be a podium finish for the coolest single image on the ‘net. [Next page](https://boards.straightdope.com/t/why-doesnt-water-cover-the-entire-surface-of-earth/988810.md?page=2)