Winterkeep by Kristin Cashore
A new land has been discovered to the east. Winterkeep is a land of miracles, a democratic republic run by people who like each other, where people speak to telepathic sea creatures, adopt telepathic foxes as pets, and fly across the sky in ships attached to balloons. But when Bitterblue's envoys to Winterkeep drown under suspicious circumstances, she and Giddon and her half-sister, Hava, set off to discover the truth--putting both Bitterblue's life and Giddon's heart to the test when Bitterblue is kidnapped. Giddon believes she has drowned, leaving him and Hava to solve the mystery of what's wrong in Winterkeep.
Lovisa Cavenda is the teenage daughter of a powerful Scholar and Industrialist (the opposing governing parties) with a fire inside her that is always hungry, always just nearly about to make something happen. She is the key to everything, but only if she can figure out what's going on before anyone else, and only if she's willing to transcend the person she's been all her life.