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This feels like an over-simplification of the benefits. I have yet to be convinced that filling an area with salted water, which by evaporating will only increase the salt concentration, can host a thriving ecosystem.

I'm also having trouble buying the argument that to lower the salt concentration we can extract it and sell the salt. Sure we can, but are talking about the same scale here?

Moreover, it may look like a hostile place, but I'm sure that in all the examples given there are populations there, maybe nomadic, and there are organisms that live there.

Finally, I find it interesting than when illustrating the Quattara seat, the author has added green around it, but I see no reason for that greening to be there at all when a few hundred kilometres north on the border of the current Mediterranean sea there's nothing. After all, same region, roughly same altitude, same water, but even higher salt concentration.

So yeah, I love the futurism aspect of the article, it makes me dream of a techno-solution, but I remain unconvinced though I'd love to be wrong.



70% of the planet is filled with salted water, which are thriving ecosystems.

Is there any reason I'm missing why expanding the ocean won't just give us more ocean?


Depends on whether the rate of salt extraction is precisely equal to the inflow over the long term. The Great Salt Lake is extremely salty and basically only two species can live in it: brine shrimp and brine flies. With about the corresponding level of "tourism" you'd expect.

And that is with industrial levels of salt harvesting. Would we expect the salt harvesting of these inland seas to be equal to or greater than the daily inflow of salt via the sea water? Seems dubious to me.

On the other hand, there are still many other benefits. Migratory birds love the Great Salt Lake. The Great Salt Lake Effect[0] on precipitation in this desert seems unambiguously positive.

[0] https://en.wikipedia.org/wiki/Great_Salt_Lake_effect


> there are still many other benefits.

Too bad it's going away.

https://www.theguardian.com/environment/2023/jan/10/utah-gre...


If you make it a bay of the Mediterranean, it should behave no differently than the rest of that ocean.

With the various pipeline/tunnel/channel options that are admittedly more realistic, at least at first, there might very well be the kind of problems you mention.


> Migratory birds love the Great Salt Lake

some birds, flying:

"hey you want to come and eat some shrimp?"

"yeah I could go for some shrimp, know anywhere good?"

"well yes actually, but it's a bit of a trek"

"okay cool, sky trip!"


That's a fair point, I only had a land ecosystem in mind when writing it, sure there would probably be plenty of sea life in there.


I think most of the oceans are a barren wasteland.

That said, as a shallow and, at least at first, nutrient rich part of the ocean it could be a flourishing part of it. But if it’s filled via underground pipe, it’ll be isolated from sources of ocean life.


    I think most of the oceans are a barren wasteland.
This is as far as I know, incorrect. I'm not sure why you think it would be true. Oceans, aside from areas like the Dead Sea are some of the most vibrant and life filled ecosystems we have. Even at the most crushing depths far from the sun there are entire ecosystems on the ocean floor.


The GP is technically correct. By volume much of the ocean is practically a wasteland because of the oxygen minimum zone [1]. A few animals like vampire squid are adapted to this zone but for the most part, the vast majority of ocean life is found in the top and bottom most layers.

[1] https://en.wikipedia.org/wiki/Oxygen_minimum_zone


From articles like this one: https://edu.rsc.org/feature/iron-ocean-seeding/2020176.artic...

Could be wrong.


But as you say: except for the dead sea.

In my mind, these new seas would have a steady influx of salt water, but only sweet water would evaporate out of them. And since I don't see the mechanism by which salt would get sequestered or removed from these bassins, I'd also guest their salt concentration would rise quite quickly.

Of course, it might still be interesting to have a huge water surface in the area that effectively serves as a rain generator, but it might not be the same thriving ecosystem we imagine when we say "ocean".


The Dead Sea is a lake, which is why it's dead.


Filling basins with ocean water will not increase the volume of sea water. It will probably increase the area of sea water (thus increasing evaporation, causing more precipitation, and speeding up the water cycle, which has a net cooling effect on the planet), and it will lower sea levels. Win win win win!


You're underestimating just how big the oceans are.


I think tidal canals would be the better option than pipelines. Dig channels deep and wide enough that the water of the seas actually mingle, letting dissolved salts spread out into the wider ocean.


For that "deep and wide enough" to work out, just how deep and wide would the canal need to be?

Such mingling happens at the Dardanelles - but it's half a mile or so wide, and ~180 feet deep.

https://en.wikipedia.org/wiki/Dardanelles


With quite a bit of extra digging this could get us an alternative to the Suez Canal which I believe many countries would be interested in and would strengthen global trade.


They already added lanes to the suez canal and I imagine it'd be way more cost effective to keep expanding those as needed.


There is a political advantage not to be solely depending on Egypt.


> I see no reason for that greening to be there at all when a few hundred kilometres north on the border of the current Mediterranean sea there's nothing.

Northern Africa is dry now, but as the north warms up this may actually change (https://www.forbes.com/sites/trevornace/2017/11/09/northern-...).

> I'm sure that in all the examples given there are populations there

Which should benefit from this the most.

> there are organisms that live there.

I just don't get the argument. Are you worried about some organisms in one of the least hospitable places? Some organisms that may live there and thrive in dry salt, but not if it was wet? What makes you specifically worried about those organisms that you dislike the potential for more and more diverse organisms if it was a sea instead of salty sand?


>Which should benefit from this the most.

But that's making an assumption about their desire, maybe they don't love the idea of being displaced and having to have another activity (tourism or whatever) in order to live.

Regarding the organisms living there, my point is we don't know what effect getting rid of such an ecosystem could have in the global scale. Maybe whatever bacteria / insect / small mammal that manages to survive there is useful for a species of bird that stops there on their way to another reproduction site. We can look at it and think by filling it with water it will be "better", whatever better means, but there are serious unknown unknowns that we can't take into account.


> there are serious unknown unknowns that we can't take into account.

We can model stuff. Also we don't find out if we don't try.

I just don't get how we are fine with causing constant large-scale intentional harm to environment for industrial purposes even as there were so many unintended consequences, but when considering a major project specifically aimed to benefit our environment and long-term humanity it's instantly the apathetic "oh but what if?".

Plus consider the amount of free clean water energy and positive uses of that as a result of this project.


Because even industrial pollution at a modern scale is small potatoes compared to the possible consequences of honest-to-god intentional geoengineering. The risks here are in a completely different league.

We recently found out that the Amazon rain forest depends on winds that carry nutrients from the Bodele depression [1]. The Amazon rainforest is nutrient limited by the phosphorus it gets from the other side of the planet. Obviously the depression is way above sea level and isn’t at risk from artificial flooding in the northern sahara, but that should illustrate the scale of the consequences we’re dealing with: if we fuck up even a little bit, it could mean ecosystem collapse in the Mediterranean or beyond.

[1] https://earthobservatory.nasa.gov/images/7279/bodele-depress...


People constantly overestimate the benefits and underestimate the harms on projects like this. Where I live we made it a point to dam up a lot of rivers to get hydroelectric power, but the dams prevented fish in the area from returning home to spawn, weakening our fisheries. And in the end the dams don’t produce that much power.


All projects like that are done for money or energy first though. We know they all come with possible environmental damage and all they do is try to mitigate it. These projects keep being done and we don't bat an eye.

This is different in that it has environmental improvements as goals. Lower sea levels a bit, enrich local ecosystem, etc. So it's a bit sad that when it comes to projects like there is always paralysis but not when we just want more stuff.


Part of it is just the audience. Your average HN comment section would likely fiercely debate the creation of crosswalks, curb cuts and other common sense improvements (though that may be true of the population at large).

If the things you felt like dont receive enough attention were available for this level of public scrutiny well, I think you can rest assured it would receive it.


Exactly - history is littered with unintended consequences.


The ship for "maybe we should not do something lest we disrupt the ecosystem with unintended consequences" has sailed.


The solution to negative unintended consequences is not to trigger more and hope that the next lot are positive.


Maybe a solution to unintended negative consequences from destructive activities that never cared about environmental impact until too late is more so a constructive project with intended positive consequences and specific environmental goals and less so the default alternative of "keep doing those destructive projects as before and stall anything else"


I always find it disappointing to see how little evaporation adds to the local greening (also see the boarders of Red Sea)


Well the Red Sea Coast has plenty of small plants, just no forests, large grasslands, etc... due to local climate.

It's probably unlikely for a verdant grassland to pop up next to the Qatta depression, but a lot of small plants I can believe.


It is claimed that a lack of trees leads to a lack of rain (leading to a lack of trees)

https://www.theguardian.com/environment/2021/mar/20/our-bigg...


[1] argues a crucial component of greening is trees "pumping" water from the oceans inland and creating nutritious soil. Otherwise evaporated water is simply blown away by the wind. I'm sure other local terrain (e.g., mountains) play a part in locally retaining evaporated water and creating conditions for rain.

[1] The Hidden Life of Trees: What They Feel, How They Communicate—Discoveries from A Secret World by Peter Wohlleben.


Agreed.

The biggest point that seemed missing to me: the author talked so much about increased evaporation, but isn't water vapor one of the worst greenhouse gases? Sure you mitigate sea level rise, but at the cost of increasing temperatures? That doesn't seem like a great tradeoff.


You are correct that water vapor is the primary greenhouse gas. Despite that, water vapor emissions are not generally considered to impact warming. I think that is because the water content of the atmosphere is already in balance due to the massive amount of evaporation and condensation (e.g. rain) that is constantly going on. If we dump some extra water vapor into the atmosphere, that will balance out as a bit of extra rain and/or a bit less evaporation somewhere else; atmospheric water vapor levels won't change.

I don't know whether a large scale, ongoing intervention, such as permanently flooding a large area, could nudge this balance sufficiently to result in a sustained (if small) increase in atmospheric water vapor content, and thus an increase in warming. An interesting question!

I wrote about the role of water vapor in global temperatures a while back at https://climateer.substack.com/i/60052576/you-thought-the-ma.... My primary source was an IPCC report, specifically the sidebar on pages 8 and 9 of this PDF: https://www.ipcc.ch/site/assets/uploads/2018/02/WG1AR5_Chapt....


The water just moves, doesn't it? He's saying to build a canal.


I guess it depends on whether such canals increase the net surface area. If you raise the ocean by 3mm across the globe, does it result in the same net increase in surface area as flooding a large swath of the Sahara?


Presumably all these could be allowed to get saltier than the seas they fill from. That would allow more water to evaporate, which would speed up the water cycle, which has a net cooling effect on the planet, and which would cause more precipitation that would then help green the planet. It would also tend to lower sea levels. Win win win win!


Well given that a fair bit of the Netherlands was made this way, I would think it's not impossible to make it usable land.


Pretty sure that none of the Netherlands were created by flooding large depressions in a desert. Quiet the opposite, in fact.


The Netherlands does not sit in a dry arid area though. When they reclaimed / drained it, it became like the areas near it.


> I'm also having trouble buying the argument that to lower the salt concentration we can extract it and sell the salt. Sure we can, but are talking about the same scale here?

Besides, this is not economical.


XKCD talked about why flooding Death Valley in this manner would be a bad idea, because unless you remove all the salt and sediments left behind from evaporation it would create a toxic waste pool https://what-if.xkcd.com/152/




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