Recently, I have been buying the Liter bottle of Evian water. It claims to be from the French Alps. And I think it tastes good.
Anyway, clearly many Liters of Evian are sold, certainly everywhere in the United States, if not the world. Clearly vast amounts of water, from these local spring wells. And this got me thinking.
Where on earth does all the world’s supply of fresh water come from? Most of the world’s surface is covered by the very salty ocean. 71%, I believe. So there is no shortage of that type of water on earth. But where does the fresh water come from?
Does it come from the ocean? I know artesian wells naturally purify water. By forcing it thru limestone? No? Is that what spring water is? Sea water desalinated thru limestone?
And this is scary. Could we ever run out of water some day? I know the water and sewage department recycles sewar water. But I assume there is still always some waste.
Yeah as Procrustus said, it’s called the water cycle. Evaporation is natural distillation. The water you drink now has probably run through its share of kidneys in its time and been around some nasty stuff. It evaporates and rains or snows down and all is mostly well with it again, barring any pollutants it picks up in the atmosphere.
When ocean water evaporates, the salt gets left behind. It comes back down as rain, so lakes and rivers are fresh water. Some rain water makes its way underground and comes out elsewhere in springs. I don’t think that rock would filer the salt out of ocean water.
In a global sense, there will always be evaporation and rain, so we aren’t in danger of running out of fresh water. In some areas, such as the American West, however, we are using more water than falls and making up the difference by extracting “fossil” water from underground, so this is a cause for concern.
To expand on that, water acts as a mild polar solvent that mediates molecular activity as well as providing a working fluid for the cardiovascular and lymphatic systems in vertebrates and more complex invertebrates, and as in interstitial fluid for arthopods for respiration and hydropneumatic functions. Barring some kind of solid state basic for life, some kind of liquid would be expected to support extraterrestrial life. Water has some unique propeties that make it well suited for life but it isn’t the only option, particularly for active chemical environments that are cold enough that pure water would freeze.
And according to the Laws of Homeopathy (stop laughing!) - there should be ‘remnants’ or ‘signatures’ or ‘electro-magnetic signals’ of all that sh!t still in the water, and therefore…
No no no! The only remnants that have any effect in water are the ones that you are explicitly paying for. Water (and remnants) is/are simply that amazing!
Well, looks like I just took a great big drink of homeopathic dinosaur piss. Yummy!
Anyway, where exactly all of this dino-piss came from is a question that I’m not sure scientists have completely cracked yet. It has long been thought that any water near the surface would have boiled away into space before Earth’s atmosphere formed. This theory obviously needs an alternate source for the water we have, so this gave rise to the theory that our water came from later bombardment by comets and asteroids.
However, somewhat recent studies (2014-ish, I believe) have found a surprising amount of water in moon rocks, suggesting that the Earth formed as a wet planet, and that even though some water may have boiled off into space, it is possible that much or most of our existing water was around since the formation of the Earth itself.
Measurements of comets have shown that the ratios of water isotopes in those comets does not match the ratio of those isotopes found here on Earth. This would argue against the comet/asteroid theory. However, we’ve only measured a few comets, and we have no idea if the ones that we have measured match the ratios of water isotopes of the ice balls out in the Kupier belt.
Another possibility is that a water-rich proto-planet, or possibly more than one proto-planet, forming in the region of our asteroid belt, actually ended up colliding with the Earth after the initial surface water boiled off. This proto-planet (or planets) possibly ended up in an unstable orbit due to the gravitational influence of nearby Jupiter. Water vapor has been observed outgassing from Ceres, which indicates a fair amount of water in the remaining asteroids, so water from this region isn’t all that of an outlandish theory.
A lot of scientists still favor the comet/asteroid theory (it’s been the leading theory for a while), but there are questions with all of these theories that probably need to be answered more thoroughly before we can say definitively where our water came from.
There’s also water inside the minerals of the Earth … something like zinc chloride hydrate = ZnCl[sub]2/sub[sub]4[/sub] … this crystal form has one molecule of Zinc Chloride and four molecules of water … this is a rock and not a liquid …
We can fashion a theory in that the shock wave of some Mars-sized object smashing into the early Earth broke this water loose where it collected on the surface …
Not really. Water does not form in Supernova explosions. But Supernovas blast out lots of hydrogen and oxygen, and later on when it interacts in cold space it can form water molecules.
I’m not sure there’s consensus on this. For example, it was recently discovered that the moon probably has a wet interior, because it looks like pretty much all the volcanic rock we find anywhere on the surface appears to have formed in the presence of water. Not oceans or anything, but mainly hydrated minerals.
This seems to me that this story is incompatible with the idea that the moon is basically a chunk of Earth’s crust blasted off in a huge collision. That picture led us to believe the moon was bone dry, but now we know there’s water everywhere - on the surface, as vapor in the exosphere, in the interior, and as billions of gallons of ice in deep craters.
That, plus the discovery of underground water oceans on numerous bodies in the solar system and evidence for a wet mantle on Earth as well suggests to me that these bodies formed in the presence of water, and water was a significant part of the protoplanetary disk that eventually collapsed into planets. I suspect we’re going to find water everywhere we go.
The cometary delivery theory was dealt a bit of a blow when comet 67P/Churyumov-Gerasimenko was shown to have water of an isotope that doesn’t match the water on Earth. But it looks like its mix of xenon isotopes matches that of Earth, indicating that that’s where we got our xenon from. But looking at how much xenon is in our atmosphere and extrapolating back shows that we could have gotten it all from comets without them really having a significant effect on the quantity of water.
I think this is something we are going to learn a lot more about in the near future. The next generation of telescopes is going to really allow us to look at planets as they are forming, and look in detail at protoplanetary discs around stars and really get a better picture of planet formation.
Oh, one other thing about the water on the moon: It was present during the Moon’s volcanically active period, most of which happened very shortly after the formation of the moon, which seemed to be too early for bombardment by comets or asteroids to have delivered enough water to the moon for it to have somehow migrated into the mantle.
There’s something big we still don’t understand about the early history of the Moon and Earth, in my opinion. One interesting new paper suggests that it formed out of a ‘Senestia’, or a torus of hot rock and vapor created when the Earth was smacked by a large impactor. Some clump of matter inside collapses gravitationally, attracts more matter, etc. While it’s doing this, matter is slowing down and collapsing to form the Earth, but by now the large bits like the moon or other large rocks just stay in orbit. Eventually, the moon sweeps out all the debris in its orbit, and the Earth forms into a planet.
if water existed in that Senestia, or was collected during the hundreds of years it would take the Senestia to collapse, then it might have been a fundamental component that makes up both bodies right from the beginning. For example, if the water attached to minerals in the Senestia cloud, those hydrated minerals could survive the heat of planet formation perhaps, and the oceans could actually be comprised of the water that outgassed from the interior and condensed on the surface.
