World of Divided Continents Q&A
Volume 4
1. Why doesn't Unlighted freeze into an eternal tundra, and why isn't Luminos a scorched, lifeless desert?
The habitability of Bastion is because of Elemental Circulation—the continuous planetary flow of Igneus (Fire), Aquea (Water), Stormut (Wind), and Terrum (Earth).
Unlighted receives warmth from Igneus heat currents in the atmosphere, Aquea and Terrum-thermal vents, and the 8-hour beam of the Sun clock.
Luminos, on the other hand, is cooled and nourished by invisible Aquea air moisture carried by Stormut air currents. Extreme climates (such as deserts or tundra) occur only in localized regions where the distribution of elements is naturally unequal or disrupted.
2. How can Underhaven be located deep subterraneanly yet possess an open sky, clouds, floating sky-islands, and vast oceans?
Underhaven is built inside a colossal interior of the Convergence Rim. Liquid-light arrays (light energy), atmospheric Ley-lines (dark energy), and local gravity grids of Underhaven generate a fully functional Earth-standard environment,unlike the surface domains, which are strictly divided into vertical tiers (Elevated Plateaus, Outer Intermediate Land Staircases, Inner Intermediate Land Biomed Caverns, Basal Lowlands, and Coastal Shelves).
Underhaven features a standard, un-tiered geography with a natural horizon like Earth's. Since there is, again, elemental circulation throughout Bastion, Underhaven is part of that circulation. You see, the elemental circulations are responsible for the clouds and sky.
The 4 elements can combine with one another and merge with either light or dark primordial elements, forming the physics of Bastion, including environmental and atmospheric physics. This is unlike Domcrean elemental use, which causes a resonance clash when the 4 elements are merging.
The 2 primordial elements, though, cannot combine even if they are based on world rather than individual physics. Since they are the Makers' unique energies, the Makers made sure that only they can combine the two primordial elements for safety and the prevention of an accidental creation of a 3rd entity that they had always feared.
So the different combinations of merging can only occur among the 4 elements and 1 primordial element. But different combinations where 2 primordial elements are involved cause a resonance clash.
Now, why did I explain all of this?
Clouds and the sky are part of atmospheric physics, which is caused by elemental circulation. Since Underhaven is part of that elemental circulation, it is also part of every physics rule, like in the surface domains. Simply saying, elemental circulation is the reason why Underhaven also has an atmosphere of its own even when situated underground.
3. So, how much is the altitude of Underhaven's atmosphere?
Note: Altitude is the distance from sea level up into the atmosphere.
Actually, Bastion is so massive (83x larger than Earth) that Underhaven's altitude (from sea level to the bottom rock layers of the convergence rim and surface domains) is at the level of our Earth's troposphere, which is about 50,000 feet or 15 to 18 km from Underhaven's sea level.
Simply saying that if you measure Underhaven's sea level until it reaches the rock layers that separate it from the surface, there is a distance of about 15 to 18 km. The atmospheric layer of Underhaven begins at about 12 km (40,000 feet). That is why it also had its airships and other modes of flying transportation.
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*End of Q&A Volume 4