Environmental Science: A Global Concern, 5th edition
Introducing students to environmental science without any prerequisites, this text has a strong global emphasis and recognizes that the world is a unified biosphere that doesn't adhere to artificial (political) boundaries. Topics covered include the Greenhouse Effect, the Clean Air Act and El Nino.
Cunningham, William P.; Barbara Woodworth Saigo; and Barry W. Barker. Environmental Science: A Global Concern, 5th edition. Boston: McGraw Hill.