Trial by Fire (Ice Age Book 1)

Mars colony, 2097. Marduk, the culmination of two centuries of breeding and genetic modification programs to reach the apotheosis of telepathic power, has discovered the reasons for his creation and fled his makers. His "family" is not far behind, but not all of them want to bring him back alive. Trying to get offworld he meets a spacer named Augustus Trask who has come from the asteroid belt with an incredible tale of living alien ships building something on one of the larger asteroids. They soon encounter a threat to Earth so monstrous that every ship, every weapon in humanity's arsenal might not be enough to stop it.

Deep at the abyssal plains of the North Atlantic, Major Sharon McKelly investigates the sudden, impossible shutdown of the thermohaline circulation, the conveyor belt of ocean currents that distributes heat throughout the planet. There she finds herself on not only the front lines of an alien invasion but caught in the heart of a war over 20 million years old. And she discovers potential allies nearly as terrifying as her enemies.

Ice Age part 1: Trial by Fire is the story of an alien assault on Earth's climate, then its population so swift and brutal that only a handful of humans react in time to offer any hope.