Grade 10 Up—A useful reader's guide and a colorful 16-page introduction precede this encyclopedia's 750 articles. Volume 1 also offers a chronology that covers the subject from 4.5 billion years ago to 2007 and notes contributors and their affiliations. However, many of them are listed as ''independent scholars'' and their affiliation or expertise is unclear. An alphabetical list of the set's entries appears in each volume. The articles cover a variety of topics relating to global warming and climate change such as social effects and scientific causes. Entries on individual countries and key figures are also included. While the articles are full of useful information, the writing is not always clear and there are grammar issues throughout that make for choppy reading. In addition, some of the content is most appropriate for AP students. The layout is basic, featuring double columns of text on each page, with a few black-and-white stock photographs scattered throughout. Entries conclude with ''see also'' references, which are not always thorough, and a bibliography. The appendix presents charts and tables of relevant data