Dr. Curtis Ebbesmeyer compiles data gathered from beachcombers all over the world who find items washed ashore from cargo spills at sea. Recovered Nike sneakers and children’s bathtub toys reveal a lot about the motion of the sea, but the motion of the sea also reveals a lot about human civilization. Human debris—shampoo bottles, fishing nets, and other sorts of trash, mostly plastic—gathers in huge masses called garbage patches. These garbage patches ride the currents of the ocean—one is bigger than the state of Alaska. They threaten the well-being of marine life and the ocean itself, and challenge us all—as individuals and as nations—to think carefully about how our actions impact the earth. Loree Griffin Burns is a new contributor to Houghton’s excellent “Scientists in the Field” series, and her dynamic writing is enhanced by ample photographs and other illustrative matter, making for an outstanding photodocumentary. (Ages 8–12)