This new "Smithsonian Field Guide to the Birds of North America" by Ted Floyd is excellent - I've not liked most bird guides that used photos in the past, but this is extremely well done. I'm using it a lot already.
Last but not least is another fine book about climate change - perhps my favorite recent book on this subject. "The Ethics of Climate Change: Right and Wrong in a Warming World" by James Garvey. Garvey is Secretary of the Royal Institute of Philosophy. His book details the facts about climate change in the first chapter, but then travels to the heart of the ethical implications of a changing climate and how it will influence many aspects of life for all people and other species as well. Highly recommended.