3.1.1 What is solar radiation?
Of all the factors that control the weather, the sun is by far the most powerful, and practically everything that occurs on the Earth is controlled, directly or indirectly, by it. The sun affects the places humans inhabit, in the kind of homes that are built, the work that is done, and the equipment that is used.
Less than one-millionth of the energy emitted from the sun’s surface travels the ninety-odd million miles to reach this planet. The sun’s energy crosses those miles in the form of short electromagnetic radio waves, identical in nature to those used in broadcasting, which pass through the atmosphere and are absorbed by the Earth’s surface. These waves warm the Earth’s ...