In this powerful first novel, global warming has killed the North Atlantic Current, sending the U.K. and much of the U.S. into a new ice age. Fifteen-year-old Willo—born in the barren, snow-covered mountains of northern Wales—has never known anything but the cold; half-feral, he barely listens when his father tells him stories of the times before the weather changed. Coming home from a day on the mountain, however, he finds his family has been taken away by government men. Then, heading back up the mountain, seeking refuge from the weather, cannibals, and feral dogs, Willo stumbles on two abandoned children. His first instinct is to “go quick away from those kids just standing all frozen and starving with their dark eyes begging me,” but his basic humanity eventually intervenes. This brutal and at times terrifying postapocalyptic tale features a well-developed first-person narrator, strong secondary characters, and spare but compelling language. Despite its grim take on humanity’s willingness to do evil, it also demonstrates that, even under the most straitened circumstances, people are capable of unexpected kindness and altruism. Ages 12–up. Agent: Greenhouse Literary Agency. (Mar.)