Download Air Mass - My CCSD

Principles of Science
Mr. Porter
Air Masses and Fronts
Air Mass - a huge body of air that
has similar humidity and
temperature throughout.
 Can be warm or cold.
 Have a lot of water vapor or very
little.
 2 or 3 can cover the entire U. S.
Air Masses and Fronts
Air masses move and bring weather
to new places.
Front - the boundary between 2 air
masses.
Warm front - occurs when a warm
air mass glides up and over a cooler
air mass.
Air Masses and Fronts
1. As warm air rises, it cools and
water condenses.
2. High clouds appear first, then
low clouds follow.
Air Masses and Fronts
3. Air pressure falls continuously
and steady precipitation begins.
4. When the front passes, skies
clear, barometer rises, and the
temperature rises as warm air
replaces cool air.
Warm Front
Air Masses and Fronts
Cold front, a cold air mass pushes
under a warm air mass.
1. The warm air mass rises quickly.
2. If the warm air has a lot of water
vapor, storm clouds form.
Air Masses and Fronts
3. Heavy precipitation follows for a
short period of time.
4. Several hours after the front
passes, the weather becomes clear
and cool.
A Cold Front
Highs and Lows
A cold air mass is usually an area of
high pressure, or “High”.
 Highs usually have fair weather.
 Air moves out from a high in a
clockwise direction and into a low in
a counterclockwise direction.
A warm air mass is usually an area of
low pressure, or “Low”.
Highs and Lows
Storms
Storms
Storms - Violent kinds of weather.
 Caused by rapid changes in the
movement of air masses.
 Includes precipitation and high
winds.
Storms
Thunderstorms
 Occurs when warm air is forced up.
 Large, dark cumulus clouds called
thunderheads form which produce
thunder and lightning.
Storms
Storms
Tornadoes -Small,
whirling, funnel
shaped cloud.
May rotate at
speeds up to 400
kph (250 mph).
Storms
Storms
Storms
Hurricanes -
Tropical storms
that cover
thousands of
km2.
 Speeds up to
240 kph (150
mph).
Storms
At the center is an area of calm air
called the eye.
All hurricanes form over the ocean
near the equator.
They need warm air and moist air to
form.
Near land, they push water on
shore.
Storms
Storms – Hurricane Ike
Storms – Hurricane Ike
Storms – Hurricane Ike
Storms
Storms
Climate Zones
Climate - describes the average weather
of a region over a year.
Based primarily on:
1. yearly temperature
2. precipitation averages
3 major climate zones:
Polar, Temperate, and Tropical.
Climate Zones
Polar
Tropical
Temperate
Factors That Affect Climate
1) Angle at which
sunlight strikes
the Earth.
 More direct the
angle the hotter the
climate
Factors That Affect Climate
2) Height above sea level.
 The higher above sea level, the
cooler the climate is
Factors That Affect Climate
3)
Proximity to a large body of water.
Factors That Affect Climate
Being close to a body of water
means…
1.
2.
More precipitation
Milder temperatures
Review
1. How is a cold front different from a
warm front?
2. What is a tornado?
3. What do hurricanes need in order
to form?
4. What is the eye of a hurricane?
Review
5. Where do tropical climates occur?
6. Where do polar climates occur?
7. How does height above sea level
affect climate?
8. What 2 effects does a large body of
water have on climate?