This chapter focuses on the sun's energy which is responsible for driving the earth's physical and biological systems.
Solar energy is the driving force for most natural phenomena at the earth's surface.
The solar constant is the amount of energy received per square meter just outside the earth's atmosphere. The earth is much cooler than the sun. It therefore emits less energy and emits that energy in longer wavelengths . Insolation or incoming solar radiation varies with the angle of the sun above the horizon and daylength. CO2 is a very important gas due to its ability to absorb radiant heat and its role in photosynthesis.