Sea & Sky (Moonfire Trilogy, Band 2)

Sanity is a lone voice crying in the desert.
The world is under increasing threat from as yet undiscovered sources of icefire, but all the people who have answers are cut off from the authorities, kings or councils, with the power to mobilise the scientists and armies to keep the world safe.
Young meteorology student Javes is stuck in the remote desert of the north. The area bristles with technology of an ancient past, but he cannot tell anyone about it because roads and telegraph lines have been cut by bad weather and invading bandits.
Lana, a fellow student, is on her way to meet him, but Aranian soldiers raid the bus that she's travelling on. She is taken to the capital to serve at the king's court.