Earth's changing climate

I recently watched the documentary An inconvenient truth presented by Al Gore (available on DVD at PCL; also in print and audiobook editions) which shows dramatic photos and charted examples of the changes to the environment since Industrialization at the beginning of the 20th century. I would recommend this film to share with your family and friends in commemoration of Earth Day on April 22nd. For a preview of what kinds of evidence is shown in the film, see these photos of diminishing glaciers in our National Parks.