The paper Glacial episodes of a freshwater Arctic Ocean covered by a thick ice shelf [1]:
> Here we provide evidence for at least two episodes during which the Arctic Ocean and the adjacent Nordic seas were not only covered by an extensive ice shelf, but also filled entirely with fresh water, causing a widespread absence of thorium-230 in marine sediments. We propose that these Arctic freshwater intervals occurred 70,000–62,000 years before present and approximately 150,000–131,000 years before present, corresponding to portions of marine isotope stages 4 and 6.
> A freshwater mass of this size—stored in oceans, rather than land—suggests that a revision of sea-level reconstructions based on freshwater-sensitive stable oxygen isotopes may be required, and that large masses of fresh water could be delivered to the north Atlantic Ocean on very short timescales.
We were taught in school it originated from the water cycle.
Essentially the salt is part of the process where we have fresh water on land, running toward the ocean carrying nutrients/minerals (including salt) into the ocean.
Put that on auto for a few million years and you have the current ocean.
All through history, availability of salt has been pivotal to civilization. In Britain, the suffix "-wich" in a placename means it was once a source of salt, as in Sandwich and Norwich.
IIRC the Norfolk Broads (an interconnected series of lakes and waterways in the same part of the country as Norwich and Ipswich) were dug by the Romans who burned peat to make salt
"The Old English ending -wic ... means farm, as in Keswick (cheese farm), or Goswick (goose farm) ... but it might denote a periodic, opportunistic beach market ... for example Lundenwic (London), Gypeswic (Ipswitch) and so on."
Supernovae, originally. As the Earth cooled, salts in rocks dissolved. When the Arctic Ocean started mixing with other oceans, the brine was entrained in over time.
Oxygen, for instance, comes from supernovae too, so following this implied line of reasoning also would water. I don't think the question was about nucleosynthesis and certainly supernovae don't eject salts, they form much later after planetary differentiation.
They asked an eli5 question, I gave an eli5 answer. Which is totally okay! Not all of us hackers spent/wasted our college years in the geosciences.
I left out lots of stuff, like chemical weathering, thermohaline circulation, glacial damming, and Milankovich cycles which probably explain a lot more... but I’m a climatologist not a geologist so there’s a whole lot more about the chemistry I don’t understand.
I've been exploring a bit what an early-primary "atoms up" learning progression variant might look like, if it emphasized atoms as nuclei. I've needed some nucleosynthesis, and stars and stuff swirling 'round the galaxy in deep time, but not much stellar evolution. Not that you couldn't teach it, but it doesn't seem required here.
Hazen's mineral evolution story was made into a NOVA. Some years back, before the NOVA, it had anecdotally been used down to high-school, but he didn't know of any attempts at middle or primary school. But it seems the usual science education dynamic is no one trying, or doing a miserable job of it, rather than hitting a rigid accessibility envelope.
The cluefulness cost space can be surprisingly shaped. Teach a 5-year old that sunlight is white, and so is the Sun, and after that second bit, they're already less confused there than most first-tier astronomy and physical sciences graduate students. I suggest we've little idea yet how early much of science might be taught, because we've been half-assing it.
This might be misread as a primordial origin event. Ocean chlorine and sodium residence times are under 100 Myr. So an ongoing process, with rocks dissolving, and excess precipitating.
Please don't do this. It's against the site guidelines (see the second-to-last at https://news.ycombinator.com/newsguidelines.html), and for good reason. Your GP comment, which was just fine, ended up being heavily upvoted—but now we have this off-topic subthread lingering on as uncollected garbage.
Downvotes are frustrating, but the only thing that really works is to examine one's comment to see what might have attracted downvotes. If you notice something, great—that's information for next time. If you notice nothing, well, that happens, and most often (not always!) other users come along and make corrective upvotes to fix the situation.
In egregious situations, if you notice a comment that's downvoted and really shouldn't be, you or anyone are welcome to let us know at hn@ycombinator.com. We'll fix it and we also sometimes remove downvoting rights from accounts that went crazy with them.
I upvoted your question because I thought it was a good question. Thanks for asking it.
Votes are an expression of the state of mind of the moderator. That’s all. They do affect and the tenor of the host environment, but only in the aggregate, over time.
You are a child of the universe. No less than the trees and the stars, you have a right to be here. And whether or not it is clear to you, no doubt the universe is unfolding, as it should.
When I was a teen, Desiderata posters were everywhere. Then, suddenly! they were all gone, and only old people remember them. Nowadays hardly anybody even remembers the ramps and crates.
I don't think "getting a couple downvotes from random strangers on the internet" means "the ability for people to have constructive and meaningful dialog here is seriously lacking"
It's one thing to get down-voted for pointing out some ideologically inconvenient thing or asking a question that's tough to answer in a logically consistent manner.
But this was a question about rocks. It's hard to find less inflammatory subject matter than that. All people had to do was take it at face value and not click a button. But they didn't they assumed bad intent. Behavior like that reflects upon the community in the same way that Reddit thinking you can't buy or sell goods via classified ads without a high likelihood getting scammed (to pick one example) is a reflection on that community.
>Reddit (at least the parts I'm on) is nowhere near as instinctively negative.
True. But once the votes start going one way or the other and the sheep can see how they're supposed to feel about a comment the votes really go wild in that direction. Controversial things here tend to bounce around a low net number of up/down votes a lot more.
I thought they added a feature to stop this from happening. It doesn't show which way the vote is going for some period of a time or something like that.
Votes go down and up and that's normal. You comment seemed skeptically dismissive, so it was downvoted. Once someone responded and you interacted in a way that showed your true interest, subsequent readers no longer perceived it as skeptical. As a result, your votes increased.
sadly, dang wants people to ignore discussions about consensus. which means questioning why any user silently disagreed is off limits and can result in more downvotes! its "unsubstantive", why wonder how to relate to the audience here, just post substantive comments no matter what! Oh ignore that rate limit that gets enabled due to community downvotes haha don't question that either.
maybe there should be a meta HN, like how stackoverflow has a meta version of the site
> Here we provide evidence for at least two episodes during which the Arctic Ocean and the adjacent Nordic seas were not only covered by an extensive ice shelf, but also filled entirely with fresh water, causing a widespread absence of thorium-230 in marine sediments. We propose that these Arctic freshwater intervals occurred 70,000–62,000 years before present and approximately 150,000–131,000 years before present, corresponding to portions of marine isotope stages 4 and 6.
> A freshwater mass of this size—stored in oceans, rather than land—suggests that a revision of sea-level reconstructions based on freshwater-sensitive stable oxygen isotopes may be required, and that large masses of fresh water could be delivered to the north Atlantic Ocean on very short timescales.
[1] https://www.nature.com/articles/s41586-021-03186-y