ed into the air, especially by cars and factories ??? ??? ??? energy-efficient provide less ??? ??? ??? erosion erosion by chemical action ??? ??? ??? glacial melts Melting glaciers ??? ??? ??? greenhouse gasses the gases in the atmosphere that trap and radiate heat; water vapor, co2, chlorofluorocarbons (CFC's), methane, nitrous oxide ??? ??? ??? habitats places where animals or plants naturally