Learn how to live green in this series from noted astronaut and environmentalist, Sally Ride that is dedicated to 3 of the Earth's main resources--air, energy, and water. Each volume describes how people use the Earth's resources and what can be done to protect them. Packed with full-color photographs and illustrations. Clean Air This volume examines how burning fossil fuels, clearing forests, and other human activities affect the Earth's climate by contributing large amounts of greenhouse gases to the atmosphere.