The purpose of this activity is to have students use an Earth Systems perspective to identify the various causes associated with changes to Earth's forests as they review Landsat imagery of site locations from around the world.

Students will review the sources of the six criteria pollutants for which the EPA has established standards for and describe their impacts on human health and the environment. 

Students will analyze how air pollution may be transported over time. Students will also differentiate between sources of air pollution and describe how air pollution interacts with the Earth System.