How does the Sun support life on Earth?
Most people know that the Sun powers photosynthesis, the conversion of light energy to chemical energy and its subsequent storage in the bonds of sugar. This chemical energy is the base of food chains that sustain the overwhelming majority of other life forms. Energy received from the Sun drives many of planet’s biogeochemical cycles, including the water cycle, the carbon cycle, and the nitrogen cycle. These material cycles provide nutrients for plants, clean water for human use, and otherwise support the array of environmental services that sustain life. Fossil fuels—oil, natural gas, coal, oil sands—are derived from the Sun. These fuels are the lifeblood of industrial civilization, accounting for about 85% of global energy use.
