Eric Brown 
Guardians of the Phoenix [EPUB ebook] 

For ten years, Paul has scrabbled for survival among the sand-shrouded ruins of the once-great city of Paris. The seas have dried up, deserts cover much of the Earth’s surface, and humanity has been all but annihilated, as much by the drought as by the nuclear and biological conflicts following the great Breakdown.Desperate bands of humans still survive. Some scrape a living in the remains of shattered cities; others resort to murder and cannibalism to survive. When Paul is rescued from one such group of killers, he joins his benefactors in their journey south in search of water and salvation.Guardians of the Phoenix tells the story of the last survivors on planet Earth, their desperate fight for survival and their last hope to save the world.