YA Futuristic Sci-Fi Novel addressing Consequences of Global Warming

Fiction. Young adult futuristic sci-fi set on Earth.

Book begins with a young woman who lived on one of the few remaining non-flooded areas of earth. Her and her family have to move to the improvised cities on stilts when the sea level rises above their home.

I read this about 10 years ago and it was found in the young adult/teen fiction section of my local library.

The version I read had a white hardback cover. The book was square rather than rectangular shaped.

I know this isn't much to go on but I would appreciate any help, thanks in advance!

I think I read this, but I can't remember the title either! Let me know if this sounds familiar: when the family moves to the new city, the young woman gets separated from them in a sort of secret under-city? And she has to find a secret way into the main city. In the main city, the people use these little things called godboxes to get information, and to receive information you place a little shiny thing called a headgem on your forehead. She realizes that she has to use one but doesn't know how, so she asks someone. The person explains it, but thinks she must be crazy or an idiot to need help with it. Does that sound like the book you read?

Yes! That sounds very familiar! Was the person who explained the headgems to her a young gentleman of about her age?

Exodus by Julie Bertagna

Thank you, lesmel, Exodus is definitely the one I was thinking of! Hope it's yours, too, Emma.BigRed.Dixon. And I think the one explaining the headgems may have been a guy, though I don't remember for certain.

Yes! Thank you so much, both of you!