Earlier quoted context omitted.
No, that "water" is actually hydroxyl groups in minerals.
No it comes out of the tap as water.
No tap water comes from the mantle.
All of Earth's water in a single sphere (2019)
161–170 of 290 posts
Re: All of Earth's water in a single sphere (2019)
#162[dead]
Re: All of Earth's water in a single sphere (2019)
#163NB: The infographic and articles are based on a 1993 publication. More recent research, from about 2017, suggests that there's about as much water in Earth's mantle as in all the oceans, so we either need another drop roughly the volume of the first, or the second drop should be greatly expanded. See: "There’s as much water in Earth’s mantle as in all the oceans" (2017) https://www.newscientist.com/article/2133963-th…
> More recent research, from about 2017, suggests that there's about as much water in Earth's mantle as in all the oceans, so we either need another drop roughly the size of the first, or the second drop should be greatly expanded.
Specifically: given that the volume of a sphere is 4/3πR^3, doubling the volume is equivalent to increasing the radius by ~26%.
Re: All of Earth's water in a single sphere (2019)
#164Earlier quoted context omitted.
The ballpark math is easy to do in your head too. The diameter of Earth is 8,000 miles, and the deepest point in the ocean, the Mariana Trench, is only 7 miles deep. It's immediately apparent that the oceans are tiny by comparison to the rest of the mass that is Earth.
Neil DeGrasse Tyson says the earth scaled down to the size of a billiard ball would be smoother than any billiard ball ever made.
Not completely accurate, it depends on your definition of smoothness. The Earth scaled down to the size of a billiard ball would have a texture more like sandpaper, certainly not what most people would consider smooth.
Re: All of Earth's water in a single sphere (2019)
#165Earlier quoted context omitted.
Given that water gets lighter when cooling down right above its fusion temperature, and that ice is a pretty good insulator. You'd have liquid water below an ice crust for a lot of time. It would eventually freeze entirely and be slowly eaten by the Sun's radiations. But that would take a pretty long time (well on a human scale).
Yeah, that's why I specified freeze over and not freeze through , although without doing the math I'm pretty sure it'd still freeze through on solar system timescales without radioactive (as in Earth's own mantle's case) or tidal (Enceladus, Europa, possibly Triton and Ganymede) heating.
Indeed, it will slowly freeze though and evaporate at the same time.
Re: All of Earth's water in a single sphere (2019)
#166NB: The infographic and articles are based on a 1993 publication. More recent research, from about 2017, suggests that there's about as much water in Earth's mantle as in all the oceans, so we either need another drop roughly the volume of the first, or the second drop should be greatly expanded. See: "There’s as much water in Earth’s mantle as in all the oceans" (2017) https://www.newscientist.com/article/2133963-th…
> More recent research, from about 2017, suggests that there's about as much water in Earth's mantle as in all the oceans, so we either need another drop roughly the size of the first, or the second drop should be greatly expanded. Specifically: given that the volume of a sphere is 4/3πR^3, doubling the volume is equivalent to increasing the radius by ~26%.
Good call, I've swapped "size" for "volume" to be clearer.
Re: All of Earth's water in a single sphere (2019)
#167Largest ocean in our solar system isn't even on Earth, apparently: > ... Ganymede’s ocean is even bigger than Europa’s—and might be the largest in the entire solar system. “The Ganymede ocean is believed to contain more water than the Europan one,” he says. “Six times more water in Ganymede’s ocean than in Earth's ocean, and three times more than Europa.” https://www.scientificamerican.com/article/overlooked-ocean-..…
Re: All of Earth's water in a single sphere (2019)
#168Yeah, but also if you took all humanity and compressed it into a "meat sphere", it would only be 1km wide [1]. [1] https://www.iflscience.com/blended-up-every-living-human-in-...
mmm... meat sphere.
Re: All of Earth's water in a single sphere (2019)
#169Earlier quoted context omitted.
Closer to a bowling ball that picked up a drop of beer from your hands.
This didn't sound right, so I did the math. The volume of all water is 1,386,000,000 km^3, which is then 1.386e+21 liters, or right about the same number of kilograms. The mass of Earth is about 5.972e+24 kg. So the percent fraction by mass is 0.0232%. A "drop" is typically estimated at 1/20th of one mL, which is then 0.05 grams. We can estimate the mass of a small-ish bowling ball at 5kg, or 5000 grams. 0.05 / 5000…
The sphere of water would have a surface gravity of 0.016 g, 1.6% of Earth's gravity, 1/10th of the Moon's gravity.
Re: All of Earth's water in a single sphere (2019)
#170I long assumed that the Earth is a "water planet" because water is mostly what you see from a distance. It wasn't until I did the math that I realized that is really about wet rocks in space vs dry rocks in space. Earth isn't made of water, it's just a damp rock. Or a bowling ball that you squirted a dozen times with a spray bottle.
There are moons out there that are more like giant snowballs - so much water that it dwarfs even our reserves.