- the only legit answer, becouse I took my time to clarify details, not like first in jumpers - upvote me for that now, muhaha
- but it will be a short one, all spelling and grammar edits are welcome as per usual
Okay with near-future tech sprinkled with advanced ones, there is hope for the project, and indeed it more how to justify it.
Technology I consider is 2D-nanomachines son, which I call smart matter and it is described to some extent in one of my answers on wb, here so as elsewhere.
So near future tech check.
How to do? What to do? Reasons.
Objective - fight the consequences of global warming.
Expected goals to achieve:
- reduce and revert global ocean level rise
- remove the shortage of drinkable freshwater worldwide
- replenish aquifers and reverse their depletion worldwide - file your request to the appropriate UN commission
- make more ice on polar caps (polls show people want it more of it there - voters we are dedicated to hearing you)
- abolish oil slavery and move to green lava energy extraction
- enrich our technology development capabilities and assist in prediction and negating effects to build A big primitive computer in orbit, very big, powerfull but old technologies from 80's, what is a potential fiat money value for its use?
- make successful pilot terraforming project for our future space projects
- extract 160t of gold from seawater
- extract 32'000t of uranium
- resolve a shortage of rare elements, table - mineral makeup of seawater
- create energy reservoir to cover all needs for humanity for the next few hundred years, with no carbon emission - green as beans, free of charge like sun
- remove CO2 released in the past 12 decades
- decrease acidification of oceans worldwide
- move dirty production inside of the new continent with full recycling
- decrease transportation cost of end goods for all countries of the Pacific region
- make a place for a spaceport for E.M.
So some reasons are possible, some are just populus vox food, some are legit, not a full list clearly. So reasons for political and such - check.
So now a little bit on how, but at the same time about energy incentive. (Ah yeah, how and such in this section - was typical politicians promise/talk to catch your attention)
How to do? What to do?
- this time for real, maybe, but no details, we keep it short, remember
Let's look at the energy aspect - if the thing is solid, then we talk 8 or a few 10's of millions cubic km's of material. Quite important is that its previous state is/was lava/magma.
Let's say Specific Heats of that magma in average 1000 J/kg/K, not an exact number but it close enough(700-1600 something like that). Temperature is 1273-1473K.
Then a cubic meter(!) of that stuff contains extractable energy around 250 kWh per cubic meter. A cubic km of it is equivalent to a powerplant producing 27 GW power over a year.
So 16 to 30 million cubic km magma definitely does contain enough energy stored in it to cover all the expenses associated with the project as energy for the project and making equipment and there will be profit, a huge one.
So basically the whole energy sector of the world economy can switch on that energy, and it may mean energy can become cheaper, with all the benefits having more for less.
So there are reasons from the perspective of economics and physics to invest limited energy, at least some percentage of it, to get access to more energy.
So the continent is a blob of lava contained by crust on sides(and the top, clearly) of it which is impregnated and reinforced by carbon nanotubes with help of nanotechnology, which helps to create such composite shell out of lava source/substance. Extracting energy on the way.
The initial sip of lava is done with help of nanotechnologies, not that it is not possible to do conventional technologies (okay, less conventional, but still technologies of our day). Nanotech serves as a tool that helps to conduct finer control of the initial stage, and as the main way to act under the crust in the way required by the whole process.
In general, it is an exchange - water and less dense cooled-down rock material from the surface with lava material from under the crust.
With nanotech, even if quite limited it may be not the best way to do things in such a way, but it may be a part of a bigger project (idk under crust intercontinental highways hypervelocity transportation routes mass drivers to space ....) so it may require to stock some lava somewhere.
- not to say nanotech here is unrealistic, do not care that some may disagree on that they do not know any better, but to have a chance to mention Pumice rafts which seems quite regular events(once or few times a decade) as result of underwater volcanoes eruptions. There is a video(s) of a yacht in such a field fascinating sight but at the same time a possibility for a floating structure.
So there are reasons, there are possibilities, there are sparks of good tech. How it all clutches all together is up to your setting. But what you won't do, is to create an underwater Yellowstone volcano eruption, you have to control the release of energy because the energy stored in those million cubic km's of magma is 2-3 orders of magnitude of the energy earth gets per year. Not even talking about the side processes of all that if you do not contain and control the process, 13 million birds just died because they ate from some random Pumice rafts in the ocean.
You need to extract material and store most of it in form of lava, like a big continent shaled storage. It also needs(as it looks like) to replace the volume of lava extracted by water or water bottled in rocks which energy you already extracted. To keep first-order effects of magma flow at bay and keep pressure and stuff. And it makes sense to stuff these rock bottles somewhere in magma to sink, maybe continental cracks and/or in similar ways to dispose of replaced water.
Other channels to dispose of it is to refill continental freshwater supplies, as depletion of aquifers is indeed a problem in some places.
So funding and efforts can be quite hefty, so as returns quite lavish, and if some does not go to space such a project is probably the only option with such lavish results, and the continent is just a byproduct. On which it makes sense to host production, recycling facilities as it basically sits on many many GW of energy.
The problem of the project it is not strategic and despite its size and scale it loses all sense and reasons in less than a hundred years if space is allowed, except the under crust transportation system which can be a start for quite a big stuff. But hey not a problem for politicians eh? I guess, lol.
In general - magma is the biggest energy reservoir on the planet which dwarfs oil, gas, nuclear fuel, even the sun as well in some sense.