Transcript Earth Science Week 25

Earth Science
Week 25
Meteorology
Tuesday Warm Up (123)
• What is air?
Meteorology Pre-Test
• 1. Which of the following is true?
– A. Water absorbs and releases heat more quickly
than land does.
– B. Water absorbs heat more quickly and releases
heat more slowly than land does.
– C. Water absorbs and releases heat more slowly
than land does.
– D. Water absorbs heat more slowly and releases
heat more quickly than land does.
• 2. At which of the following latitudes would
you expect to find the warmest average
temperatures each year?
– A. 10 degrees N
– B. 23 degrees N
– C. 15 degrees S
– D. 37 degrees S
• 3. Which of the following would be LEAST
likely to affect Georgia’s climate?
– A. Earth’s tilt
– B. maritime polar air masses
– C. the Atlantic Ocean
– D. maritime tropical air masses
• 4. Which of the following statements about
warm air masses is correct?
– A. They have higher pressure than cold air masses.
– B. They move over cold air masses at warm fronts.
– C. They are denser overall than cold air masses.
– D. They move under cold air masses at cold fronts.
• 5. In what direction are the global winds
blowing in most of the continental United
States?
– A. to the northeast
– B. to the southwest
– C. to the northwest
– D. to the southeast
• 6. At which of the following latitudes would
you expect to find the lowest air pressure?
– A. 15 degrees N
– B. 30 degrees N
– C. 45 degrees S
– D. 60 degrees S
• 7. It is a hot, humid summer day. What kind of
change in weather conditions would be MOST
likely to cause a tornado?
– A. a decrease in pressure
– B. an increase in temperature
– C. a warm front
– D. a cold wind
• 8. At which of following latitudes would a
hurricane be MOST likely to develop?
– A. 12 degrees N
– B. 52 degrees N
– C. 28 degrees S
– D. 44 degrees S
• 9. Which of the following is MOST similar in
structure to a hurricane?
– A. a thunderstorm
– B. a tornado
– C. a cold front
– D. a warm front
• 10. A hurricane gains energy as water vapor
– A. evaporates
– B. condenses
– C. rises
– D. freezes
Standard S6E4a
• Demonstrate that land and water absorb and
lose heat at different rates and explain the
resulting affects on weather patterns.
Standard S6E4.b
• Relate unequal heating of land and water
surfaces to form large global wind systems
and weather events such as tornadoes and
thunderstorms.
Standard S6E4.c
• Relate how moisture evaporating from the
oceans affects the weather patterns and
weather events such as hurricanes.
Layers of the atmosphere
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Troposphere
Stratosphere
Mesosphere
Thermosphere
Ionosphere
Troposphere
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Lowest layer
7 to 20 km thick
Next to Earth’s surface
Densest layer
Contains 90% of total mass of atmosphere
Where weather occurs
Temperature decreases with altitude
Stratosphere
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Home of the Ozone layer
Gases are layers, do not mix much
Air is very thin and contains little moisture
Lower layer very cold: -60 degrees C
Temperature rises with altitude
Top is at 50 km
Mesosphere
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Middle layer
50 km to 85 km above Earth’s surface
Coldest layer: -93 degrees C at top
Temperature decreases as altitude increases
Thermosphere
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Upper layer
From 85 – 90 km to 500 – 1000 km
Temperature increases with altitude
1000 degrees C
Does not feel hot, temperature is average
movement of particles in motion. Not enough
particles to collide and cause energy transfer.
• Space shuttle and ISS orbit in thermosphere
Ionosphere
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Home of auroras
Part of thermosphere
Gas particles are electrically charged – ions
Reflects AM radio waves
Exosphere
• Above thermosphere
• Atoms and molecules escape to space
Atmosphere Layer Diagram
• Create a line graph showing change in
temperature as altitude increases through
layers.
• Add a second line graph showing change in air
pressure as altitude increases through layers.
• See page 450 in textbook.
Wednesday Warm Up (123)
• Describe air pressure.
Atmosphere Layer Diagram
• Create a line graph showing change in
temperature as altitude increases through
layers.
• Add a second line graph showing change in air
pressure as altitude increases through layers.
• See page 450 in textbook.
Thursday Warm Up (123)
• Why is the Earth warm enough to support
life?
• Why is the Earth cool enough to support life?
Atmospheric Heating
• Radiation: transfer of energy as
electromagnetic waves.
• The sun radiates energy to earth
Conduction
• Heat transfer by direct contact
• Air molecules come into contact with warm
surface of Earth and transfer energy to the
atmosphere.
Convection
• Transfer of heat by circulation of a liquid or
gas.
• Air is heated, becomes less dense and rises.
• Cool air is denser and sinks.
• Cool air is then heated by Earth’s surface and
begin to rise again.
• Convection current.
What happens to energy from sun?
• 25% is scattered and reflected by clouds and
air.
• 20% is absorbed by ozone, clouds, and
atmospheric gases.
• 50% is absorbed by Earth’s surface.
• 5% is reflected by Earth’s surface.
Greenhouse effect
• Sun sends down short wave energy
• Earth re-radiates as thermal (long wave)
energy.
• Water vapor and carbon dioxide trap thermal
energy and radiate it back to Earth.
Global Warming
• If more energy comes in from sun than is reradiated out to space, the globe will become
warmer.
• One hypothesis is that human activities that
release carbon dioxide, such as burning fossil
fuels, causes global warming.
• Another hypothesis is that earth goes through
periods of warming and cooling due to activity of
the Sun, changes in tilt and magnetic field that
also cause global climate change.
Assignment
• Section Review p. 457
Friday Warm Up (123)
• What is wind?
• What causes wind?
Wind
• Movement of air caused by differences in air
pressure.
Global Winds
• Unequal heating of Earth causes differences in
air pressure.
• Equator gets more direct sunlight, air is
warmer and less dense and rises. Low
pressure at equator
• Poles get less direct sunlight, air is colder,
more dense and sinks. High pressure around
poles.
Pressure belts
• Bands of high and low pressure about every
30 degrees of latitude.
• High pressure belts near 30 degrees N and S of
equator.
• Low pressure belts near 60 degrees N and S
latitude.
Coriolis effect
• Apparent curving of wind and ocean currents
due to Earth’s rotation.
• Northern hemisphere winds traveling north
curve East and winds traveling south curve
west.
Polar Easterlies
• Wind belts from poles to 60 degrees latitude.
• Carry cold arctic air over the United States
producing snow and freezing weather.
Westerlies
• Wind belts between 30 degrees and 60
degrees latitude N and S.
• Flow toward poles from west to east.
• Carry moist air over US producing rain and
snow.
Trade Winds
• Winds that blow from 30 degrees latitude
almost to the equator.
• Curve to west in Northern hemisphere and
east in Southern hemisphere.
Doldrums
• Trade winds meet around equator.
• Little wind because warm, rising air causes
low pressure.
Horse Latitudes
• 30 degrees north and south latitudes
• Sinking air causes high pressure
• Weak winds
Jet Streams
• Narrow belts of high speed winds that blow in
upper troposphere and lower stratosphere
• Up to 400 km/hr
• Affect movement of storms
• Affect speed of aircraft
Sea Breezes
• Blow toward land in day because air over
water is cooler and sinks (high pressure) and
air over land is warmer and rises (low
pressure).
• Wind moves from high to low pressure
Land Breezes
• Blow toward water at night
• Air over water is warmer at night and rises
forming an area of low pressure.
• Air over land is cooler and forms an area of
high pressure.
• Wind blows from area of high to area of low
pressure.