Despite the technical/scientific flaws in the world building, and there are a few, I enjoyed this book. This world is darkly disturbing, yet fascinating. I'll be reading more in this trilogy.
I'm still mulling things over, so I'll probably be adding to this.
1. If all other continents are destroyed due to action/actions taken in a war, it is highly unlikely that one would survive basically intact or that major climatic changes wouldn't affect life.
2. The basic social structure has understandably fallen apart. Having children is emphasized in order to keep the human race going. Girls are kidnapped to be wives and bear children before they die. However, if found unacceptable, ie not pretty enough, they are sold into prostitution or killed. These two ideas don't quite mesh. No matter how plain a girl may be, she still should have some value as a future mother.