Subject(s): Nature and Effect of human beings on. -- Pollution. -- Earth as a system : geologic past of earth , Ozone shield, pangaea, ice age, Current warm phase -- System interactions : atmosphere, oceans, land and humans -- Humanity - agent of global environmental change, Changing the face of the earth, Agriculture and industry -- Global environmental changes : Global warming, Food water and changing climate, Irrigation, Coastlines and rising seas, ozone layer and ultraviolet radiation, Vanishing forests and vanishing species, Soil erosion, rain machines, Forest resources -- lakes, forests and acid deposition : lakes, forests, Building and monuments, Controlling acid deposition -- Global change and our common future