The Chasm was an excellent sequel to The Calling. I recommend both books for fans of adventure-driven science fiction with an array of very interesting characters.
Finding Humanity
Review: The Calling (Finding Humanity #1) by Branwen O’Shea
The Calling is not your typical YA science fiction story, and there was a lot to this world beyond the ice age and the sickness, but the characters and the conflict between them were what really drew me in.