City on the Currents — Brian S. Matthews

The animals are getting smarter. The ants have learned how to take out entire settlements in a single night. As Mother Nature closes in on humanity's remnants, five people set off on a journey to a legendary city built on the remains of America's last aircraft carrier. The floating utopia is anything but. Corruption rules its darkest corners, and there are things in the ocean far worse than anything that walks on land.