Transcript Chapter 8 - TeacherWeb

Chapter 8
Section 3-5
(section 1-2 info is in your
Water Cycle Presentation)
Section 3 Air Masses-
a huge body
of air that has similar temperature,
humidity, and air pressure at a given height.
Types of air masses:
• Maritime Tropical
• Maritime Polar
• Continental Tropical
• Continental Polar
Maritime-over the ocean,
humid
Continental-over land, low
humidity
Tropical-warm
Polar-cold
How air masses move• Prevailing Westerlies-
•
•
major wind belt over
US, usually west to
east.
Jet Streams- high
speed air masses
embedded in the
westerlies.
Fronts- the boundary
where two air masses
meet.
Types of Fronts
• Cold fronts- cool,
dense air
• Warm fronts- warm,
less dense air
• Stationary frontswhen cold and
warm air meet,
neither one can
move
• Occluded fronts-
where a warm air
mass is caught
between two cold
air masses
Section 4 Storms!
• A violent disturbance in the atmosphere.
• Thunderstorms with heavy precipitation, including
•
•
•
•
thunder, the sound of an explosion, and lightning, an
electrical charge.
Tornadoes- a rapidly whirling, funnel-shaped cloud over
land that reaches down from a storm cloud to the earth.
Snow storms- large amounts of precipitation in the form
of snow.
Hurricanes-tropical cyclone, which is a swirling center of
low air pressure, winds of 119 kph at least, begins over
water, the “eye” of a hurricane is the calm inside the
middle.
Floods- after a major downpour of rain, flash floods can
occur.
Section 5 Predicting Weather
Meteorologist- scientists
who study the causes of
weather and try to
predict it. They use
maps, charts and
computers to forecast the
weather.
Reading a weather map:
Symbols, color for
temperature and lines are
used to show the
direction of winds, fronts,
etc.