Aah, by “sea”, the OP means “mosquito-plagued seasonal wetland”, that changes everything…
Also worth noting that the areas around the Okavango are neither a Mediterranean playground nor a tropical paradise. They’re the same old semi-arid Kalahari as they’ve always been. See also: Sudd, The
Despite inflation cheap laugh is still cheap these days.
Joking aside, the problem with a desire to make in inland sea or lake really are just about only ever going to be that.
A further issue is as raised above. In order to affect climate you need a deep body of water. One that can maintain currents to get the heat out. A good example of a shallow body of water that does little but make the climate even more miserable is the Persian Gulf. With an average depth of about 50m it is unable to moderate the climate, and places like Dubai, despite being on the coast are, depending in the season, either horrendously hot, or brutally hot and humid. Dubai airport is forever getting fogged in. Nothing grows there except for skyscrapers.
The movement of water needed to create geographical sized changes in climate are geographically sized volumes of water. Not just kilometres wide, but kilometres deep. This isn’t accomplished with tiny human scratches on the surface. It is accomplished mostly with plate tectonics.
I appreciate all the informative posts here, which have really helped me understand various facets of the this issue.
What is it about Australia that makes people want to change so much?
Ever since Capt’ Cook looked at Botany Bay and said “This looks like a nice place”, there has been scheme after scheme to alter it - some drastic - let’s do away with those pesky natives, and some less so, but still pretty disastrous. Ask an Australian about Cane toads or rabbits and see what they think about mucking about with their unique ecosystem.
Get off the plane at Sydney with some fruit in your baggage, even if it is the apple the airline gave you for lunch, and you might think it is stuffed with cocaine. Try to sneak an undocumented pet in and you may well find yourself being sent straight home.
Several points -
Perhaps a better model might be what is being done to recover the salt flats that used to be the Aral Sea. They built a dyke across the northern half to reduce the amount of evaporation area; the small northern part is slowly refilling and may actually be a viable fishing source in a few years or decades.
But the area suffers from the same problem as the Colorado River and Salton Sea. Decades of agricultural run-off and over-irrigation have created toxic dust that pervades the area.
A similar project to what the OP proposes is the siphon to refill the Dead Sea. they start from the advantage that - it’s already dead. More salt would not be a big deal. Running from the Gulf of Aqaba over a hump, it will also conveniently provide hydro power on the way down, but only because we’re talking 1000 feet of downward, not a few feet. For now, the Dead Sea is slowly(?) lowering at about a meter a year, because of (what else?) excessive taking of irrigation water from its primary feed. So the OP would suggest creating a giant Dead Sea in the middle of Australia.
Due to earth’s rotation, coriolis force, and prevailing weather patterns, I assume any benefit from evaporation - higher precipitation - would most likely accrue east of the lake, which is not the place that more desperately needs more precipitation. Again, would this rain actually fall on the land, or simply travel east enough to fall in the Pacific? Is there a benefit?
Other projects are as mentioned, filling the depressions south of the Mediterranean, perhaps reaping some benefits from any change in the weather. I recall a book (published in the Soviet Union in the 70’s) that described assorted projects - the most interesting was a giant dam on the Congo river, which would creat a giant lake flooding the Congo basin (can you say environmental impact boys and girls?). The dam, if high enough, could allow water to diver to refill Lake Chad and then on to the sea from there. Far too sdisruptive, though.
Another project is the Toshka Lakes. There’s a branch off lake Nasser (there thanks to the Aswan Dam) that can feed a series of lakes and possibly create a second Nile River valley, creating desperately needed new farmland in Egypt. For now, the Sudan’s massive dam project has inhibited the flow of the Nile and any such plans; The same problems exist as with other posts above - can the plan actually provide enough water flow to counter evaporation and provide a benefit without diminishing the existing Nile ecostructure?
(Recall an article about irrigation after Aswan - Egypt discovered salt buildup on farmlands when the river no longer flooded. Even fresh water has a modicum of dissolved salts. Egyptian farmers learned they had to over-irrigate regularly to flush out salts that accumulated from evaporation)
The destruction of the Aral Sea really must be one of the worst ecological disasters of the modern era.
What’s fascinating is how resilient the Aral is. They built the dyke across the constriction point south of the north arm, and apparently it is filling up again and fish are returning (surprisingly).
That makes me wonder about the feed into Lake Eyre. Can they build a series of berms to corral the water so that a passable lake can grow in one area; then allow the overflow to carry the dissolved salt to the next area and so on until the up-river ponds are fresh water…
I remember being in Ayers Rock park when there was a significant rainfall. Driving out to KIngs Canyon the next day, there were no bridges on the roads, but a few spots had measuring sticks stuck in the shoulder of the road to indicate whether when the water was flowing across the road, the depth was minor or too deep to pass. (If so, wait a hour or two and it would go down, I presume). When I went by, it was less than a foot deep.
On further inspection of Google Earth, it looks like there are several choke points on rivers leading into Lake Eyre. The real question would be - why bother? What’s the benefit?
The upstream ponds are fresh water.
It’s just that they only fill intermittently, it may be decades between flows.
It is a rare event that water flows into Lake Eyre when there is still water from the previous inflow.
Yep.
Surprisingly, the Aral sea started when a river of the Caspian sea changed course in ancient times and gave birth to the Aral Sea, it disappeared just before the birth of Christ and then returned. Then the Soviets ruined it.
One comment here though, keeping the lake made the ecosystem to be better for fish animals and humans. Once it was gone the southern area became a toxic wasteland.
Still, that video does end with a hopeful view of the northern Aral Sea. Perhaps something that Australia could look at.
Didn’t the Soviets either test or store chemical weapons on an island of the Aral Sea? I seem to remember reading about that. And then because of the lowering water level, people were worried about those chemicals getting spread around more. That may be part of why it’s a toxic wasteland.
The reason the area is a toxic wasteland is because the salt deposited in the lake bed is full of toxic metals, agrochemicals, and pesticides from irrigation runoff. It has nothing to do with chemical weapons.
Same problem as mentioned above for the Salton Sea. Only thing is, size matters.
I just found this topic here, years after it was asked and discussed.
Odd as this is, on 6 MAR 2020 I wrote a Blog page on this subject.
Welcome, Wayne!
The OP’s idea seems more than a bit off the wall, but I’ve been interested to read what others have to say about it. Let’s just say I won’t be investing in the project.
You know, a variation of this idea was the basis for one of Jules Verne’s last novels, L’Invasion de la mer (“The Invasion of the Sea”). It was the last of his works published in his lifetime, in 1905.
There were several real proposals to flood a low-lying section of the Sahara near the Mediterranean Sea to create a “Sahara Sea”. It would be a salt sea, of course, but it would have a mediating effect on the climate and would bring more moisture to the air, resulting in more rain.
The novel wasn’t translated into English until almost a century later.
I had a small book back in the 70’s published by a Soviet publisher about global engineering. One of the more audacious projeects was to build a giant dam at one of the Congo River rapids, where it was a choke point. A three mile dam (fairly high) would create a lake level high enough to divert some of the water north to refill Lake Chad - and then some. Same concept, a giant body of water would help alter the climate to increase rainfall, allow irrigation, etc.
You know, we’ve flown some great hypothetical kites on The Dope in the past couple of decades. But rarely has there been one more emphatically refuted on the basis of the sheer engineering impracticality, insurmountable physical incumberances, unachievable hydrological targets, for nebulous, spurious, unquantified benefits with associated speculative fiscal wantoness on a global scale for a pipe-dream (heh!) that equivalent projects have incontrovertibly proved environmental disasters.
So you’re saying there’s a chance…?