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SECTION 2. CLIMATE AND WEATHER

1. Climate
Climate is the word used to describe the general year after year weather conditions in a
particular region or area. When a particular area is described, the geography of the area and
its climate are closely related. Some of the major factors that determine the climate of an
area are as follows:
a. The Temperature Zone. The temperature zone that an area is located in is usually a
major factor in its climate. See figure 5.
b. Humidity. The amount of evaporated water in the air is a major factor in the
climate of an area. Clouds are formed when evaporated water condenses into very small
drops of water. Larger drops become precipitation that falls as the area's rain, snow, sleet,
and hail.

c. Movement of the Air. The air that makes up the earth's atmosphere does not remain in one place
but moves about the earth. Cold polar air moves across the temperate zones, as does tropical air.
Maritime air from overseas and oceans moves across the continents, and continental air moves over
other parts of the continent, or out over the seas. The movement of air is a major climate factor.

d. Elevation. The height of an area above sea level is often an important climate factor. As a
general rule temperatures decrease as height or altitude above sea level increases. Higher
areas usually have cooler or colder climates than low regions in the same area. See figure 5.

e. General Geography. In addition to the general temperature zone an area is located in,
other geographic factors that are important to a climate can be the availability of surface
water in the form of oceans, seas, rivers, and lakes, and the location of mountain zones that
control the movements of the air in a region or area. See figure 5.

2. Weather

If climate is a word used to describe the general year-to-year weather conditions in an area,
then weather is the word used to describe the day-to-day atmospheric conditions. Since
everybody experiences the weather conditions around him throughout his life, weather is
discussed in nontechnical terms by all people. Some of the more common terms used to
describe particular weather features are listed below.

a. Temperature. Days are described as hot, cold, cool, or warm; or thermometer
temperatures are given in degrees Celsius or degrees Fahrenheit.

b. clouds. Days are described as being clear, cloudy, or overcast. Clouds on the surface are
called fog. Certain clouds, particularly if they are black colored, are called rain clouds or
thunder clouds.