In this world, global warming has reached a tipping point. The equator has reached temperatures well over 212 degrees Fahrenheit (100 Celsius, 373 Kelvin), resulting in the "Boiling Sea". Global companies saw an opportunity to connect the wrecked world after massive flash floods by damming off parts of the equator and building equatorial train systems on it. Underneath these giant systems, small, climate-controlled submarines are now called home by thousands of refugees from a radical pirate group called the Bermudans (named after the Bermuda Triangle) who roam the new oceans, which now take up even more of the Earth.
Humans have created climate-controlled suits to help them survive the heat, but many series of earthquakes have separated the continents into cracked collections of islands with thin rivers in between each. In North and South America, the islands are wider apart and people now have with chalky or ashen skin due to the old eruption. New wars over territory have arisen, but a new effort, headed by the New United State-Isles, called the Armada, has relieved much of the world from governments of their own, leading the the U.S.I/Armada to take over much of the world.
Is ANY of this remotely possible? The flooding, the islands, the eruption, the human race SURVIVING this. Oh, and nuclear war has somehow never happened ;).