Transcript SC.912.e.7.6

SC.912.E.7.6
Relate the formation of severe
weather to the various physical
factors
Earth Systems and Patterns
• The scientific theory of the evolution of Earth
states that changes in our planet are driven by
the flow of energy and the cycling of matter
through dynamic interactions among the
atmosphere, hydrosphere, cryosphere,
geosphere, and biosphere, and the resources
used to sustain human civilization on Earth.
DAY 1
• THUNDERSTORMS
• What causes a thunderstorm?
Severe Storms
Thunderstorms
 Occurrence of Thunderstorms
• At any given time, there are an estimated 2000 thunderstorms in
progress on Earth. The greatest number occur in the tropics
where warmth, plentiful moisture, and instability are common
atmospheric conditions.
 Development of Thunderstorms
Thunderstorms form when
warm, humid air rises in an
unstable environment.
VOCABULARY
thunderstorm
lightning
tornado
Thunderstorms and Tornadoes
Thunderstorms form in warm, moist, unstable air.
They produce lightning, a discharge of electricity.
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Heavy rain
1. Cumulus Stage Air rises
2. Mature Stage
and a cumulus cloud forms.
The rising air is called an
updraft. The updraft prevents
precipitation from reaching the
ground.
The precipitation becomes
heavy enough to fall
through the updraft and
reach the ground. The
falling precipitation creates
a downdraft.
Light rain
3. Dissipating Stage The
downdraft weakens the updraft,
eventually cutting off the supply
of moist air rising to the cloud.
The cloud begins to evaporate.
Stages in the Development
of a Thunderstorm
What causes a thunderstorm?
Thunderstorms form
when warm, humid air
rises in an unstable
environment.
DAY 2
TORNADOES &
HURRICANES
What kind of front is associated with the
formation of tornadoes?
Explain why a hurricane quickly loses its
strength as the storm moves onto land.
Severe Storms
Tornadoes
 Tornadoes are violent windstorms that take
the form of a rotation column of air called a
vortex. The vortex extends downward from
a cumulonimbus cloud.
 Occurrence and Development of Tornadoes
• Most tornadoes form in association with
severe thunderstorms.
• A mesocyclone is a vertical cylinder of
rotating air that develops in the updraft of
a thunderstorm.
Thunderstorms and Tornadoes
Tornadoes can develop in thunderstorms containing rotating updrafts.
Mesocyclone
Inflow
Wall cloud
Inflow
Tornado
Formation of a Mesocyclone
What kind of front is associated
with the formation of tornadoes?
Tornadoes often form in thunderstorms
that develop along cold fronts because
air masses on either side of the front
have very different temperature and
moisture conditions.
Satellite View of Hurricane Floyd
Severe Storms
Hurricanes
 Whirling tropical cyclones that produce
winds of at least 119 kilometers per hour are
known in the United States as hurricanes.
Severe Storms
Hurricanes
 Occurrence of Hurricanes
• Most hurricanes form between about 5
and 20 degrees north and south latitude.
The North Pacific has the greatest
number of storms, averaging 20 per year.
Severe Storms
Hurricanes
 Development of Hurricanes
• Hurricanes develop most often in the late
summer when water temperatures are
warm enough to provide the necessary
heat and moisture to the air.
Explain why a hurricane quickly
loses its strength as the storm
moves onto land.
There is not sufficient moisture .
The rough land surface causes
winds to subside.
DAY 3
• Compare/ Contrast Hurricanes and Tornadoes
Create a Chart of
Tornadoes and Hurricanes
• Include the following information:
–Location
–Associated storms
–Pressures associated with storm
FCIM QUIZ
• Day 4