The Dying Sun and the Frozen Moon

The world is literally caught between a sun that is growing too hot and a moon that is freezing the oceans. The World: People live in a thin strip of land called "The Temperate Belt." The Plot: The "Fire" side is expanding, pushing the desert into the cities, while the "Ice" side is sending massive glaciers to crush the ports. A group of specialized "Weather-Weavers" must travel to the two poles of the planet to reset the ancient machines that keep the world from burning up or freezing solid.