Download Unit 8 Day 5

Unit 8 Day 4
Weather Systems
The Coriolis Effect on Earth causes moving particles
Focus Question
How can the weather conditions in Canada affect our
weekend?
VA SOL
SOL 3
The student will investigate and
understand how to read and interpret maps, globes,
models, charts, and imagery. Key concepts include
–a. maps (…..
) and
SOL 13
The student will investigate and
understand that energy transfer between the sun and the
Earth and its atmosphere drives weather and climate on
Earth. Key concepts include
–b.
Enduring Understanding
Energy transfer between the Earth’s surface and the
atmosphere creates the weather.
The atmosphere remains in balance until acted on by
an
.
(air molecules ) to
in
the northern hemisphere and to the left in the southern
hemisphere
Global Wind Patterns
For thousands of years mariners have utilized
predictable wind patterns to navigate the globe. There
are
per
hemisphere. Meteorology now provides an
understanding of the reasons for these reliable winds
Weather Systems
Heat energy on Earth is in constant motion as it flows
from areas of higher temperature to areas of lower
temperature. This heat flow creates our
that transport colder air to
warmer areas and vice versa in a constant balancing act
of heat energy
If Earth did not
Coriolis effect
predicting weather would
be much easier. Cold air at the poles would flow
towards the equator and displace the warm air which
would rise and flow back towards the poles as it cools
in the upper atmosphere, but since it does spin and
since
material the prediction is
far more difficult

occur at where the
warm, rising air from the equator begins to cool and
sink. They occur below 30 degrees latitude and blow in
an
direction
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Question
How do you think this wind pattern got its name?
Horse Latitudes
Along the 30 degree line the sinking air causes a belt
Jet Streams are narrow bands of fast, high-altitude,
westerly winds and flow at speeds of
Their position varies and
weather systems
km/hr
of high pressure with very little horizontal movement.
Sailors used to refer to these as the
because they would sometimes
in the calm seas and have to throw their
horses overboard because they couldn’t feed them
Prevailing
Global Wind Patterns
flow between 30 and 60 degrees
latitude and blow from west to east. This pattern is
responsible for much of the weather in
Fronts
Since air masses of different characteristics are
constantly in motion some of them are bound to
eventually
Winds are named for the direction
Front is the
separating two air
masses of
Density differences are caused by differences in

blow from east to west
between 60 deg and the poles and are characterized by
Jet Streams
Often the weather report will state that the
is affecting today’s forecast in some way.
Earth weather is strongly influenced by atmospheric
conditions and events between the wind zones
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There are
main types of fronts and the

occur where a
interaction of colliding air masses often causes dramatic cold air mass
changes in weather
and wedges it upward. It then collides with another cold
front and causes precipitation on both sides
Pressure Systems
The vertical movement of air combined with the

occur where cold, dense
air displaces warm air and we see clouds, showers, and
thunderstorms
coriolis effect results in the formation of
low and high pressure systems
High Pressure System
High Pressure Systems are formed by
and move in a clockwise
direction (in the northern hemisphere)
–
High pressure is associated with fair weather

are where advancing
warm air displaces cold air and we see extensive
cloudiness and precipitation

are where the two
air masses meet but neither advances. Little cloudiness
and precipitation is seen
Low Pressure Systems
Low Pressure Systems form by low density rising air
moving in a
direction
–
Low pressure is associated with
weather