Half a croissant, on a plate, with a sign in front of it saying '50c'
h a l f b a k e r y
Trying to contain nuts.

idea: add, search, annotate, link, view, overview, recent, by name, random

meta: news, help, about, links, report a problem

account: browse anonymously, or get an account and write.

user:
pass:
register,


                                                                                                                   

Irrigate the entire Sahara

Bring rainfall to Sahara and harvest salt.
  (+3, -1)
(+3, -1)
  [vote for,
against]

This idea injects steam into the atmosphere of North Africa where it condenses to prove life giving rain. A byproduct is high quality table salt.

First, dig a tunnel from Fiji to central Sahara, that is right through the centre of the globe.

Let sea water flow into tunnel at Fiji end.

Water falls towards centre of the earth where it is heated by the molten iron down there. Water is violently evaporated and is ejected with great force out the Sahara end of the tunnel.

Steam goes high into atmosphere and condenses as rain.

Sahara turns into desert paradise and everyone from California goes to live there.

Stop water flow at intervals and collect high quality sea salt that has begun to accumulate in the evaporation zone.

KiwiJohn, Dec 03 2003

Australian Sea http://www.halfbake..._20Australian_20sea
[bungston, Oct 04 2004]

Lake Death Valley http://www.halfbake...ke_20Death_20Valley
[bungston, Oct 04 2004]

Tunneling through liquids http://www.iijnet.o...-bridge-tube01.html
Plan for submerged bridge tube tunnel between Japan and South Korea. [kropotkin, Oct 04 2004, last modified Oct 06 2004]

The center of the earth http://www.seismo.u...s/100/interior.html
What we're dealing with here, kids. [Overpanic, Oct 04 2004, last modified Oct 06 2004]

(sort of) alternative http://www.lookat.c...ticleview/212/1/103
Tunnel from the sea to the Sahara? [chud, Oct 04 2004, last modified Oct 06 2004]

No tunnel required http://www.toprak.org.tr/isd/can_63.htm
"For example the average water collection rates during the fog collection seasons in Chile, Peru, and Oman were 3, 9, 30 Liter/m2/Day respectively" [Klaatu, Oct 04 2004, last modified Oct 06 2004]

When it rains, it pours. http://www.mortonsalt.com/
[thumbwax, Oct 04 2004, last modified Oct 06 2004]

Amazon link to Verne book on Sahara http://www.amazon.c...ce&s=books&n=507846
Invasion of the Sea (1905) [cloudface, Oct 04 2004]

Sahara forest Sahara Forest
(jutta, please make ideas links case insensitive) [pashute, Nov 29 2012]

[link]






       And what would you build this magical tunnel out of?
Worldgineer, Dec 03 2003
  

       Perhaps a few well-placed canals from Morocco inland.
RayfordSteele, Dec 03 2003
  

       You'll spend a fortune on plumbers regularly extracting all the Architeuthis plugs...
Tiger Lily, Dec 03 2003
  

       The salt accumulates where the water is boiled - deep underground in the magical tunnel.
Worldgineer, Dec 03 2003
  

       I feel really let down, I thought the title was IrriTate the entire Sahara. I'm so pissed, I wont even read your idea before I bone it.
ato_de, Dec 03 2003
  

       Why don't you spin some turbines and generate electricity with the steam? I guess because geothermal power is already well-baked.
toiyabe, Dec 03 2003
  

       If we dug that tunnel, and it flooded with water, wouldn't it cool off the earth and cause a lot more problems then how do we harvest leeched in salt? Perhaps? Or is the earth thick enough that if the tunnel to suck in water was built, it would leech in ALL of the earths water? I think that would happen. The area inside of the globe has to be larger than the suface. Right? Even if you could regulate it with a big ol magic tunnel. still too big. Big ol magic tunnel.
lizziepunkin, Dec 03 2003
  

       There is a very large area in Libya that is below sea level. You could pipe the Mediterranean in there a la "Australian Sea" (linked) or put an in line desalinator a la "Lake Death Valley".   

       What is with the tunnels thru the earth lately?
bungston, Dec 03 2003
  

       At least we keep a lot of wizards employed. After the internet-bubble burst they were a hard-up group for work. Many were turning to dark magic.
RayfordSteele, Dec 03 2003
  

       Sahara salt may not be gourmet quality but Fiji salt is.   

       The tunnel is not magic, just hard to do.   

       ravenswood, last time I checked a column of sea water was much heavier than a column of steam, no?
KiwiJohn, Dec 03 2003
  

       Melt the arctic with a giant hairdryer! Hoover up Japan, and put it on stilts above Guadeloupe. Flood Zimbabwe with brandy, and explode Norway. What?
Fishrat, Dec 04 2003
  

       I wish I could give a croissant to Fishrat's fine scheme there.
bungston, Dec 04 2003
  

       The Sea of Tranquility?
lubbit, Dec 04 2003
  

       [Fishrat] - I hope you're planning on putting Japan at a vertical slant, otherwise it will overrun Guadeloupe and there's no knowing what chaos that will cause.
PeterSilly, Dec 05 2003
  

       [kiwijohn]. This tunnel is utter fantasy and is only possible via magic. You mention drilling this tunnel right through the core but do you remember your geography lessons at school? ok, think back.   

       Under the crust, is the mantle which is effectively a fluid.   

       The core itself is almost certainly liquid.   

       How do you tunnel through liquids without magic? You can't ... sorry, got to fish this.
jonthegeologist, Dec 05 2003
  

       <How do you tunnel through liquids without magic?>
Why, with bubbles of course.
  

       // How do you tunnel through liquids without magic? You can't ... sorry, got to fish this. //   

       Yes you can. See link.
kropotkin, Dec 05 2003
  

       [kroptokin], that's water, not molten magma.
k_sra, Dec 05 2003
  

       Hey, hey, it's not my problem how to make the tunnel, the sucessful tenderer will have to sort that out.. few ides for her though..   

       Make pipe of some substance (ceramic perhaps?) than can withstand heat of the magma. Push this tube (capped of course) down through the crust, once you are past the solid stuff it will become easier. Continue building and pushing until you strike sand of the Sahara.   

       Second for their consideration, drill down to liquid then pump sea water down to cool and solidify the tunnel wall as you go, same as a 'lava pipe' as occurs in volcanic area near Hawaii.
KiwiJohn, Dec 05 2003
  

       Hey, hey, it's not my problem how to make the tunnel, the sucessful tenderer will have to sort that out.. few ides for her though..   

       Make pipe of some substance (ceramic perhaps?) that can withstand heat of the magma. Push this tube (capped of course) down through the crust, once you are past the solid stuff it will become easier. Continue building and pushing until you strike sand of the Sahara.   

       Second for their consideration, drill down to liquid then pump sea water down to cool and solidify the tunnel wall as you go, same as a 'lava pipe' as occurs in volcanic area near Hawaii.   

       Magic is magic, hard is solvable one day.
KiwiJohn, Dec 05 2003
  

       One more time.   

       [KiwiJohn] First of all, realize that magma is liquid rock. It is also, as the outermost layer of liquid rock, the coolest liquid rock. As you go down, things get hotter. Much hotter. In fact, much, much hotter. About 4,300 degrees hot. Celcius. That's hot enough to melt steel.   

       Wanna know something else? At the depth of 5,200 kilometers, which is where you would have to dig to reach the limits of the inner core, there is (surprise!) a stunning amount of pressure. How much? Enough to keep the iron core of the earth a solid while it is still thousands of degrees above its melting point.   

       Let's assess.   

       You would need a tunnel that is approximately the length of 1/3 the circumference of planet earth, over 13,000 Km long. This tunnel would have to be thick enough to withstand the insane pressures that exist at the core (my guess is 20 miles thick, at least), and built of a material that won't melt, or even become soft at 5,200 degrees celcius. You would also have to drill through a solid iron core, which is under so much pressure that it should be a liquid. Oh, and it's 2,300 km thick. Heh. Plus, once you've made it to the center of the earth (congrats!) you now have to do this all uphill...90 degrees.   

       And all that's aside from the points that [ravenswood] has already raised. I hope you have your wizards ready.
Overpanic, Dec 05 2003
  

       Dig hole to magma.
Drop sand in hole.
Sand turns to Glass.
Insert long pipe.
Blow real hard.
Form Glass vessel.
Fill Glass vessel with water.
Water evaporates.
Sahara is irrigated.
Rinse and repeat.
thumbwax, Dec 06 2003
  

       He he, this is more fun that I thought!
KiwiJohn, Dec 06 2003
  

       [thumbwax] It sounds like you're trying to make the galaxy's largest bong ... doooooood
Letsbuildafort, Dec 06 2003
  

       It would be a lot easier just to make Nuclear powered or solar powered high out put pumping stations on the Meditraineen or Atlantic coasts, or Red Sea. But i do like the idea of fixing the sahara, I also would wonder if this would cause an Ice age because the last time the sahara was a rain forest was in the Ice age, Climate on the earth tends to have more rainfall on the equator. Between the equator and tropics of cancer and capicorn there is usually less moisture. Also didn't they do this in a place east of california, they moved all the people from california into a dessert where they built a Big Dam and people started gambling and stuff.
JCL2004, Dec 06 2003
  

       Folks, the big difference between this and the Australian Sea, 'Dig Canal From Moroco' type projects is that this one injects steam directly into the atmosphere. There is no local evaporation.   

       Considering that the world is not yet ready for a hole through the middle I am prepared to allow the sucessful tenderer to instead dig a tunnel (or drill a big diameter hole) at an angle from near the African coast to intersect with another such tunnel dug from inland in the Sahara somewhere. The point of interection would be as deep as possible according to available engineering techniques but in any case deep enough for the available heat at that level to cause instant evaporation of the sea water.   

       So, water pours down one tunnel, is heated to steam and shoots out the other with enough force to go, say, 5000 feet into the atmosphere. Remember the tunnel filled with steam will be a lot lighter than the one filled with sea water.   

       Dang, no one has noticed that this scheme would produce salted rain so I have yet been unable to introduce the concept on inland kelp farms.
KiwiJohn, Dec 06 2003
  

       We are not historically really really good at 'fixing' the earth. I would suggest that the Sahara and the Libyan depression mentioned earlier will eventually be filled with water without any magic tunnel, just keep the coal-fired electricity going to run that great western society and the remains of Antarctica will take care of the rest.
wave_man, Dec 06 2003
  

       You might get molten salt, though.
lubbit, Dec 06 2003
  

       //they moved all the people from california into a dessert // No [UB], that is NOT the Big Apple. Even if you DID have a big starter.
gnomethang, Dec 06 2003
  

       I do not have any real concern that the salt will stay to block up the tunnel, instead it will be ejected along with the steam and as soon as the steam condenses the salt crystals will dissolve and we will have salted rain. There might even be a bit of salt crystal rain too.
KiwiJohn, Dec 07 2003
  

       <shriek>Make it go away</shriek>
lubbit, Dec 07 2003
  

       [kiwi] But you still disagree that steam would come pouring out of BOTH ends of this pipe?
Overpanic, Dec 07 2003
  

       A much easier way to irrigate deserts <link>
Klaatu, Dec 07 2003
  

       *blinks* the physics of this terribly hairbrained (in the worst way possible) idea render it utterly nonsensical. Boring through the core of the earth in itself won't work, let alone trying to get water to flow through it. But let's say it will, in some crazy crazy way. It is easily shown that a particle (or by extension, a mas of particles) would oscillate back and worth in such a tube in simple harmonic motion. So the water would never actually flow out of the hole -- it would merely fill it up and the fluid as a whole would remain like a plug in the earth. The individual particles would oscillate, but the Sahara would be as dry as it was before. And the fish in Fiji are going to be mighty pissed at you taking their water for such a silly idea.
andromeda, Dec 07 2003
  

       Even if you don't go through the center of the Earth, and just go far into the crust you will essentially have a large geyser or an undersea vent depending on what you want to do. How about if you desalinate the sand in the Sahara and then irrigate it through smaller means. Plant green things. Fishbone.
sartep, Dec 07 2003
  

       Make resort beaches and a new rain forest at the same time.   

       Skip the geyser engine. Scoop all the Saharan sands to the western edges of the continent and into the Atlantic. These newly created North African beach fronts should tweak the water cycle to dump loads of precipitation on the continent's interior. Soon...soon, you should have at the least some marshland, though this may distress the land of Shangri-La next door.
Tiger Lily, Dec 07 2003
  

       //I do not have any real concern that the salt will stay to block up the tunnel, instead it will be ejected along with the steam and as soon as the steam condenses the salt crystals will dissolve and we will have salted rain. There might even be a bit of salt crystal rain too.//
  

       Morton Salt's catch-phrase: When it rains, it pours.   

       Where, oh, where is Afro Assault when you need 'im the most?
Who else has been through Utah and seen the HUGE amounts of salt?
thumbwax, Dec 07 2003
  

       This idea is (kind of) already baked, by a science fiction writer named Jules Verne. 1905. L'Invasion de la Mer (The Invasion of the Sea) (Below from http://epguides.com/djk/JulesVerne/) "Captain Hardigan and other members of the French forces in Tunisia accompany an engineer named de Schaller on a survey of the abandoned plans and works of Captain Roudaire. M. de Schaller plans to resurrect Roudaire's plan to create a sea in the midst of a lower portion of the Sahara Desert. All goes well on the survey trip, until the party is attacked and captured by members of the Tuareg tribe, whose leader Hadjar had recently escaped the custody of the French. The party manages to make their escape from the Tuareg only to find themselves almost captured again, until an act of nature cuts them off from the Tuareg. NOTE: Was published in English for the first in Dec of 2001."
cloudface, Jun 01 2004
  

       Irritate the entire Sahara
normzone, Jun 01 2004
  

       This is one of those ideas that, by the book, should probably be deleted but, due the volume and interesting nature of the discussion, I won't be deleting.
bristolz, Jun 06 2004
  

       The first time I read this, about 6 months ago, I thought it was sheer lunacy, but rereading it today it's grown on me. The engineering required seems, um, ambitious, to say the least, but the physics is quite intriguing.

The key to getting this to work is to insulate the tunnel on the way down, and not on the way up. Then as the water reaches the lowest point, it is converted to very high-pressure steam. The enormous pressure of the column of descending water (which, btw, will help the tunnel in resisting the pressure of the earth) will stop the expanding steam from going back where it came, and force it to go the other way. This conversion point must be at the lowest point of the tunnel, to prevent the more bouyant steam bubbling up through the water. With gravity being neutral along the tunnel (at the lowest point the tunnel is horizontal) the steam will simply go towards the area of lower pressure. Since the superheated steam will be moving much much faster than the descending water, the pressure on the upward stretch of tunnel will be less than that on the downward stretch (by Bernouilli's theorem). And, exactly as [Kiwi] hoped, a jet of superheated steam will emerge to wreak ecological mayhem in the sahara. Yay.
spacemoggy, Jun 06 2004
  

       I see several ideas that involve drilling holes either partially or entirely through the planet. These ideas set of all sorts of lights and whistles. What you do with the material from the hole? If the tunnel is only 1 meter in diameter your talking 10,000,000 cubic meters of rock(eventually). That's 60,000,000 tons! how does it come out? Piling it on the Earth's surface would cause a wobble in our rotation. What about the nuclear contamination of the steam? Don't forget whats at the core of our little floating rock here. What's wrong with the Sahara? Just because WE can't comfortable live there it needs to be changed? Environmental nightmares all over this one. Not even funny if it was intended as a joke.
Spare parts, Jun 25 2004
  

       The only thing is that the Sahara is growing; taking over what used to be forest and grassland.
RayfordSteele, Jun 26 2004
  

       Last I checked, the sahara was shrinking, being pushed back by humans irrigating stuff, and increased rainfall due to global warming.
Madai, Nov 29 2004
  

       [+] for the geothermal water idea.   

       So don't do it from Fiji, do it off the Mediterranean shoreline and use the steam to push the water inland. Repeat the process every 10 km, and finally have the steam released in an area where it will create clouds over the Sahara. QED.
pashute, Nov 29 2012
  

       brb, immigrating to Zimbabwe
Voice, Nov 29 2012
  

       You only need to convert a portion of the water into steam, then you can use it to pressure-force the rest of the water out, in a gigantic garden sprinkler situation.
BunsenHoneydew, Dec 30 2012
  
      
[annotate]
  


 

back: main index

business  computer  culture  fashion  food  halfbakery  home  other  product  public  science  sport  vehicle