# The three greenhouse gases of greatest concern are carbon dioxide, nitrous oxide, and methane. Greenhouse gases trap heat in the atmosphere to keep the Earth warm, which is known as the greenhouse effect. They cause climate change.
# Without the greenhouse effect, Earth would be freezing cold at nearly -18 degrees Centigrade.
# The Earth takes up about half the carbon dioxide produced by humans. Plants, soil, and water take up carbon dioxide. If stored for a long time, it is known as carbon sequestration.
# Legumes like peas and soyabeans make their own nitrogen fertiliser from the air. This reduces emissions of greenhouse gases from agriculture.
# Cattle produce methane due to the fermentation in one of their four stomachs, known as the rumen. Bison, deer, and sheep, too, emit methane into the atmosphere.