Survey
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
Energy and Winds Nature of Energy Living organisms need energy for growth and movement. Energy The ability to do work! The combination of energy and matter make up the universe What is the source of our energy? The source of practically all our energy is the Sun. Heat Transfer Heat transfers in three ways: Conduction Convection Radiation Conduction The transfer of heat from one particle of matter to another by direct particle to particle contact. Convection The transfer of heat through movement of matter. Occurs in liquids and gases Radiation Transfer of energy through electromagnetic waves Matter is not required Radiation from the sun! Why is Chicago Known as the Windy City? ► Wind is the movement of air from an area of high pressure to an area of low pressure. ► It is the movement of air caused by uneven heating of the Earth's surface. ►Global air circulation follows a general pattern of convection . Air flows from the equator to the poles and back again. ►The area near the equator receives the most concentrated solar radiation, causing the air above it to heat up rapidly. As it heats up, it expands, becoming less dense and more buoyant. ►This change in density causes it to rise. Air at the very top of the rising mass cools. ► The cooler the air gets, the more dense it gets causing it to sink back to earth. This cooler air is forced to flow toward the equator, where the process begins again. ► The key factor driving convection is density – warm air is less dense and more buoyant than cold air. Density Air Pressure ► Local air circulation ► During the day, land absorbs heat from the sun better than water, so it warms up faster and warms the air above it ► Water holds heat better than land, so it warms the air at night. In a high pressure area, air will (rise, sink) because the air is (less, more) dense. This is because the air is (cold, warm) and (rises, sinks). In a low pressure area, air will (rise, sink) because the air is (less, more) dense. This is because the air is (cold, warm) and (rises, sinks).