World Turned Upside Down by Elyse Springer

After three winters in Antarctica, Simon Bancroft is an old hand on the ice. The harsh weather and extreme isolation aren't for everyone, but he enjoys the tight-knit community at McMurdo Station... and lately he's enjoyed watching the hot new researcher, Asher Delaney, who's recently arrived to study the aurora. But Simon's just a janitor. Asher doesn't even know he exists.

When Simon's friends propose a wager, he gets a chance to introduce himself to Asher at last. But Asher defies all of Simon's assumptions, and suddenly he finds himself reevaluating everything he thought he knew about Asher, himself, and falling in love at the bottom of the world.