this post was submitted on 18 Nov 2023
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If no immediate action is taken to counter the harm, desalination, in combination with climate change, will increase the Gulf’s coastal waters temperature by at least five degrees Fahrenheit across more than 50 percent of the area by 2050, according to a 2021 study published in the Marine Pollution Bulletin on ScienceDirect, a site for peer-reviewed papers.

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[–] [email protected] 20 points 11 months ago (1 children)

Who would've thought that building a massive city in the desert is a stupid idea.

[–] [email protected] 6 points 11 months ago

When all you've got it money and desert, that's where you build

[–] [email protected] 8 points 11 months ago* (last edited 11 months ago) (4 children)

Wait, desalination causes seawater temperatures to rise?

[–] [email protected] 8 points 11 months ago (1 children)

But to maintain its opulence, the city relies on fresh water it doesn’t have. So it turns to the sea, using energy-intensive desalination technologies to help hydrate a rapidly growing metropolis.

All of this comes at a cost. Experts say Dubai’s reliance on desalination is damaging the Persian Gulf, producing a brackish waste known as brine which, along with chemicals used during desalination processing, increases salinity in the Gulf. It also raises coastal water temperatures and harms biodiversity, fisheries and coastal communities.

I was wondering too

[–] [email protected] 8 points 11 months ago (1 children)

You’d think the brine could be “mined” for lithium, sea salt, and other mineral content. Then disposed of in the desert rather than thrown back into the sea.

[–] HobbitFoot 6 points 11 months ago (1 children)

At that point, you're evaporating all the water out to get the minerals left, which can be a lot more energy intensive as the boiling point of the brine will get higher as water is removed.

And in the end, you're going to end up with a gigantic salt flat in a windy part of the world. If you are lucky, all you are doing is just making a part of the land more toxic. If you are unlucky, that salt could get airborne and cause its own environmental issues.

[–] [email protected] 3 points 11 months ago* (last edited 11 months ago) (1 children)

Interesting. We’re going to have to figure out something. The middle eastern desert isn’t the only place running out of fresh water.

I will note that evaporation pools are nothing new and don’t require a lot of energy. If you can extract the minerals that are worth something, the process could pay for itself.

https://youtu.be/YMDJA4UvXLA

[–] HobbitFoot 1 points 11 months ago

Perhaps, but this is going to radicaly alter both how current desalinization plants operate and the supply chain of salt.

It doesn't seem to be insurmountable, but it is going to be a big deal going forward. At least the main users of desalinization technology are in locations with abundant solar energy.

[–] [email protected] 3 points 11 months ago

Yes, with several common processes

[–] [email protected] 2 points 11 months ago

I was curious too. The article mentions that Dubai’s old reverse osmosis systems rely on flash distillation which adds a lot of heat to the system and thus the brine being returned to the gulf waters.

“Unlike reverse osmosis, which removes salt and other contaminants by pushing water through a semipermeable membrane, multistage flash distillation relies on heat. Decades ago, when the U.A.E. began exploring desalination, the technology could better handle the Gulf’s high salinity, though reverse osmosis can now do the same. And although both technologies create brine, the byproduct of multistage flash distillation is far hotter, further disrupting the ecosystem.“

[–] [email protected] 0 points 11 months ago (1 children)

closed system, the less water there is to disperse heat energy it gains from sunlight/underwater vents, the more heat energy the water retains. it's basic mathematics.

[–] [email protected] 0 points 11 months ago (1 children)

It seems like you do not know how the water cycle works, even though you posted about this theory twice.

[–] [email protected] 2 points 11 months ago

yes, please do explain about the water cycle in and off a desert peninsula surrounded for thousands of miles by nothing but salt water and deserts. you're only going to need to explain it to me once though, lol, don't forget the thermodyanics

[–] [email protected] 2 points 11 months ago

As it turns out, Earths ecosphere is a close system surrounded by lifeless cold space. One action, begets another equal and opposite reaction. When you reduce the amount of water volume into a system being heated by the sun and underwater thermal vents, that water will get and remain hotter, longer. I mean, who knew, right.