Guided Notes on the Causes of Weather Chapter 12, Section 1

Meteorology is the study of atmospheric phenomena.

2. Hydrometeors are cloud droplets and forms of precipitation that contain water in any phase. Lithometeors are smoke, haze, dust, and condensation nuclei. Thunder and lightning are electrometeors, which are manifestations of atmospheric electricity.

3. Weather is the current state of the atmosphere 3. Weather is the current state of the atmosphere. Usually this refers to short-term variations. Long-term variations in weather for a particular area is the climate. It is usually averaged over a 30-year period.

4. The Sun’s rays are more spread out when they strike the Earth at a low angle. Thus, solar radiation at the poles is less intense. This explains why the tropics are warmer than the poles.

5. The continual motion of air and water reallocates heat energy and brings it into balance. Virtually everything that we consider to be weather is part of the constant redistribution of Earth’s heat energy.

6. An air mass is a large body of air that takes on the characteristics of the area over which it forms. The region over which an air mass forms is the source region, and it can be either land or water.

List and briefly describe the 5 major types of air masses: Continental Tropical: (cT) warm and dry Maritime Tropical: (mT) warm and humid Continental Polar: (cP) cold and dry Maritime Polar: (mP) cold and humid Arctic: (A) much colder than continental polar

8. Air masses eventually move from their source region and transfer heat from one region to another, establishing a heat balance in the process.

9. An air mass undergoes air mass modification when acquires some of the characteristics of the new surface beneath it. Eventually, an air mass’s characteristics are the same as the new surface over which it is travelling. At this point, the air mass has lost its original identity and is now part of the air over a new source region.