Christian Science Monitor: At 38 years old, Earth Day seems to be entering a midlife identity crisis. By one estimate, some 1 billion people around the world will do something to observe the anniversary of the first Earth Day in 1970, a landmark in the history of the environmental movement. But attitudes and activities will vary widely. While some celebrate nature’s beauty and wonder, others will protest environmental degradation and demand action. Today environmental concerns are aired year-round: …