Students from around the world calculated their class mean and standard deviations for their footprints and posted them on our world map.
Do you see differences across the globe? If so, why do you think those differences exist?
Did you use the calculator to try to reduce your footprint down to the average from a citizen of another country? What changes would you have to make to lower your footprint in this way? Are you going to try and take some of these actions in your daily life?
Student Footprints >
What Causes Acid Rain?
Acid rain results when sulfur dioxide (SO2) and nitrogen oxides (NOX) are emitted into the atmosphere and transported by wind and air currents. The SO2 and NOX react with water, oxygen and other chemicals to form sulfuric and nitric acids. These then mix with water and other materials before falling to the ground.
While a small portion of the SO2 and NOX that cause acid rain is from natural sources such as volcanoes, most of it comes from the burning of fossil fuels.