Temperature, in the form of heating and cooling, plays a key roll in our atmospheres circulation. Heating and cooling is also the key in the forma-tion of various air masses. These air masses, because of temperature contrast, ultimately result in the formation of frontal systems. The air masses and frontal systems, however, could not move significantly without the interplay of low-pressure systems (cyclones).

Some regions of Earth have weak pressure gradients at times that allow for little air movement. Therefore, the air lying over these regions eventually takes on the certain characteristics of temperature and moisture normal to that region. Ultimately, air masses with these specific characteristics (warm, cold, moist, or dry) develop. Because of the existence of cyclones and other factors aloft, these air masses are eventually subject to some movement that forces them together. When these air masses are forced together, fronts develop between them. The fronts are then brought together by the cyclones and airflow aloft. This produces the classic complex frontal systems often seen on sur-face weather maps.

In this unit we will discuss air masses in lesson 1. We will progress to fronts, the relationship of air masses and cyclones to fronts, and the various frontal types in lesson 2. Lessons 3 through 6 will cover the various types of fronts. Lesson 7 concludes with the modification of fronts.

At the end of this unit you will find a practical training exercise that pro-vides hands-on practical experience and training.

Privacy Statement - Press Release - Copyright Information. - Contact Us - Support Integrated Publishing