On Earth something is always burning. Wildfires are started by lightning or accidentally by people, and people use controlled fires to manage farmland and pasture and clear natural vegetation for farming. Fires can generate large amounts of smoke pollution, release greenhouse gases, and degrade ecosystems. But fires can also clear away dead and dying underbrush, which can help restore an ecosystem to good health. In many ecosystems, plants have coevolved with fire and require periodic burning to reproduce. The fire maps in this video show the locations of actively burning fires monthly. White indicates as many as thirty fires in a 1,000-square-kilometer area per day. Orange indicates as many as ten fires, while red areas indicate as few as one fire per day. 2000–2020.