Download Ch 18 Note Outline

Name ____________________________________________________Date ____________
Foundations of Science
Ch 18 The Atmosphere
Vocab: 18.1 – troposphere, temperature inversion, stratosphere, ozone, mesosphere, thermosphere, greenhouse effect
18.2 – water cycle, transpiration, precipitation, humidity, relative humidity, dew point, barometric pressure, Coriolis effect
18.3 – air mass, front, isobar, climate, topography
18.1 Characteristics of the Atmosphere
Layers of the Atmosphere
Earth’s atmosphere consists of a variety of gases.
 _________________________________________________________
Layers – differ in temperature, density, and amount of certain gases
 _______________________________________________________
o Closest layer to the crust
o __________________________________________________
o ____________________ because of the weight of gases above
o _________________________ (6°C/km) as altitude increases
o ____________= top of troposphere where temperature stops
decreasing
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o Temperature inversion= sometimes cold air in troposphere
gets trapped beneath warm air; this is one reason for smog
pollution
 _________________________________________________________
o Contains ____________________________________________
o Temperature ________________________________________
o Very little water vapor – little weather, no storms
 _________________________________________________________
o Temperature _________________________________________
 _________________________________________________________
o Very hot layer 980°C; gas molecules are far apart
 _____________________________
o In between ____________________________________, where
electrically charged ions are formed
o Electrons in ionosphere reflect radio waves, better at night
o Auroras, colorful light displays occur: aurora borealis
Note: Temperature is the _______________________________________
 Fahrenheit to Celsius: °C = _________________________________
 Celsius to Fahrenheit: °F = _________________________________
Changes in the Atmosphere
When Earth solidified – volcanic eruptions released gases and created
the atmosphere. Oxygen was not in this early atmosphere.
Bacteria and single-celled organisms lived in this early
environment.
_______________: Plants use carbon dioxide to produce oxygen while
making energy from sunlight.
___________: Animals use oxygen to produce carbon dioxide, making
a cycle.
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Name ____________________________________________________Date ____________
Foundations of Science
Man-made chemicals can deplete the ozone layer
 1985 scientists reported a lower concentration of ozone
 Thought to be caused by increase of _________________________
(CFCs); gases used as refrigerants and propellants in spray cans
which can break down ozone molecules.
__________________= natural condition where atmospheric gases trap
sun’s Energy
 If too much heat is trapped, the global temperature will rise.
Some scientists say that this is happening and damaging the
Earth.
18.2 Water and Wind
Water Cycle
Movement of water in troposphere: ______________________________
_________________________________________________________
Humidity
 the amount of water vapor in the air
o _____________________________________________________
 the amount of water in the air ______________________________
 at _________________ air molecules _________________ allowing
the water molecules to condense and fall out of the air
 at __________________ air molecules are ________________ for
the water molecules to join up and fall out of the air
Relative Humidity
 measure of the amount of water vapor that the air is holding
compared to the amount that it can hold at a specific
temperature
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 saturated= _______________________________________________
__________________________________________________
o saturated air = _______________________________________
 _________________________
o the temperature at which air is saturated and ____________
takes place
o dew point changes with the amount of moisture in the air
Condensation
 ________________________________________
 for water vapor to condense, air must be cooled below its dew
point
 cooling can happen by
o ____________________________________
o ____________________________________
o ____________________________________
o ____________________________________
 condensing water vapor needs something to hold onto to
condense
o _____________________________________________________
_____________________________________________________
 salt – ocean sea spray evaporates
 surfaces and nitrates – natural sources and burning
fuel
 condensed liquid is a fine mist as fog when the warm ground
meets the cold air
Cloud formation
 clouds form when water vapor begins to condense around small
particles of dust, salt and smoke in the atmosphere
Cloud classification: ___________________________________________
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Name ____________________________________________________Date ____________
Foundations of Science
3 main types of clouds
 ________________________________________
o appear when layers of air cool below their dew point
temperatures
o ____________________________________________________
o ____________________________________________________
o associated with both fair weather and precipitation
o drizzle comes when these clouds are low and gray
o fog= when the air is cooled to its dew point and condenses
____________________________________________________
 ________________________________________
o ____________________________________________________
o they form when air currents rise, and water condenses
o ____________________________________________________
o associated with fair weather and thunderstorms
 ________________________________________
o ____________________________________________________
o ____________________________________________________
o ____________________________________________________
o associated with fair weather and approaching storms
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Other clouds are combinations of these 3 main types
 Nimbus Clouds
o added to one of the 3 main clouds
o ____________________________________________________
o they are so full of water that no sunlight penetrates them
Rain capacity
 when water droplets combine and reach the size of 0.2 mm they
become too heavy and fall out of suspension in the cloud
Air Pressure - (______________________________________________)
 pressure from air in atmosphere above measuring instrument
 measured in _____________________________________________
 Barometers
o Mercury barometer = ______________________
o Aneroid barometer = more portable; no liquid
 overall pressure depends on temperature, density, and amount
of water vapor in air
o
temperature =
pressure
o
temperature =
pressure
o
density =
pressure
o
density =
pressure
o
water vapor =
pressure
o
water vapor =
pressure
 ________________________________________________________
o when the air can’t rise, clouds can’t form = nice weather
 ________________________________________________________
Winds
 Pressure gradient: ________________________________________
 Air is pushed from _______________________________________
 So, winds result from the uneven heating of the atmosphere
 warm air rises faster creating a pressure gradient force
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Name ____________________________________________________Date ____________
Foundations of Science
 heated island surrounded by cooler water becomes a region of
low pressure, causing winds to blow toward the land
 _________________________________________________________:
North winds come from the north.
The Coriolis Effect – __________________________________________
 Winds normally blow from high-pressure areas to low-pressure
areas. However, the Earth is rotating as well. Due to this effect,
the path of the wind does not move in a straight line relative to
land. Winds are turned to the_____________________________ in
the North Hemisphere and to the ________________________ in
the Southern Hemisphere
 Northern Hemisphere: winds flow clockwise around highs and
counterclockwise around lows
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Circulation Cells, Pressure Belts, and Wind
 Due to Coriolis effect, earth’s rotation affects direction of wind
 Earth’s rotation=
wind starts=
wind blows=
 The winds between the pressure zones are named from the
directions that they flow from
o North
+ coriolus effect=
o South
+ coriolus effect=
 Both the Northern and Southern Hemisphere have three wind
belts: _________________________________________. The winds
move in vertical loops called __________________.
o ________________________________, because hot air rises.
o 30° N latitude has a ____________-pressure belt
o 60° N latitude has a ____________-pressure belt
Trade winds: Found between the equator and 30° N and 30° S
 Warm and steady in both direction and speed
Prevailing winds: Winds that blow from the same direction on the
average
18.3 Weather and Climate
Weather
 ____________________________ and describes current conditions
 caused by the interaction of ______________________________
 National Weather Service depends upon meteorologists and
satellites
Meteorologist
 Study the weather; specifically temperature, air pressure, winds,
humidity, and precipitation using machines such as ___________
_______________________________________ attached to weather
balloons
 Information
weather maps
predictions
Air Masses
 a large body of air with ___________________________________
content
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Name ____________________________________________________Date ____________
Foundations of Science
 has the same properties as the surface over which it develops
o ____________________________________________________
o ____________________________________________________
o ____________________________________________________
o ____________________________________________________
Fronts
 A front is the boundary between ____________________________
 Weather occurs at fronts due to the interaction of the air masses
 Air moves from high pressure systems to low pressure systems
High
Low
Hot
Cold
pushes Low up
o As the cold air converges into the low pressure system, it
pushes the warmer, less dense air upward
o As the warm air rises it cools and reaches its dew point and
the water vapor condenses forming clouds
Cools=
clouds form
Hot
Cold
pushes Low up
 When a cold front meets a warm front the air does not mix
1. ____________________________________________________
2. ____________________________________________________
3. ____________________________________________________
4. ____________________________________________________
____________________________________________________
 Fronts usually bring a change in temperature and always bring a
change in wind direction
 Most changes in weather occur at the 4 major front types
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 Front symbols
 Cold front
o _____________________________________________________
o Rapid speed of advance causes steeper slopes than warm
fronts
o Can causes a narrow area of ____________________________
_____________________________________________________
 Warm front
o _______________________________________________________
______________________________________________
o Gentle sloping front because of slower movement
o As warm mass rises, it cools and __________________________
_______________________________________________________
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Name ____________________________________________________Date ____________
Foundations of Science
 Stationary front
o When ___________________________, the front does not move
o Pressure differences cause a warm front or cold front to stop
moving for several days
o _______________________________________________________
 Occluded front: ___________________________________________
Occurs when cold, cool, and warm air come together
o _________________: _____________________ under a cool
front and an overlying warm front
o _________________: _____________________ slides in between
a cold front and an overlying warm front
o Both cause warmer air to rise; strong winds and heavy
precipitation
Precipitation
 ____________________________________
 When air rises high enough and in large enough quantities,
precipitation occurs
 ______________________________________________________
 Higher the air rises, the more moisture it can drop
 Rainy areas of the Earth (NW coast of USA)
o windward side of mountain range
o storm areas
 hurricanes, typhoons, low pressure zones, and fronts
 warm air rises, cools, and drops water
o areas favored by the global wind belts at the equator where
air has no choice but to rise causing daily thunderstorms
Thunderstorms
 Heavy rain, lighting flashes, thunder and sometimes hail
 ______________________________________________________
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 Warm, moist air moves upward rapidly, cools, condenses, and
forms cumulonimbus clouds up to 10 km high
1. Water droplets fall, collecting other drops
2. The falling rain causes downdrafts which form strong
winds
 Lightning= ______________________________________ resulting
in a build up of electrical charges (+ & -); can travel easily
through water
 Thunder
o Results from the ________________________ around the
bolt of lightning then its cooling
o Moving molecules cause sound waves: 25° C to 30,000° C
Tornadoes
 Violent whirling wind that moves in a narrow path over land
and through the clouds
 _________________________________________________________
_________________________________________________________
 Wind shears: differences in wind direction and speed: causes
funneling
 _________________________________________________________
_________________________________________________________
 Begins as a ___________________________ of water droplets
Hurricanes
 A large, __________________________________________________
______________; also called _____________ (Indian Ocean) and
______________ in (Pacific)
 Warm ocean water evaporates; warm water vapor rises causing
_____________________________________ that can gain strength
 As water vapor rises, it condenses into clouds… releases energy
 Occur when SE tradewinds meet up with NE tradewinds in
North Atlantic
 Start in the north hemisphere between 5° and 20° latitude; move
slowly and are powerful
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Name ____________________________________________________Date ____________
Foundations of Science
Weather Maps
Map showing weather conditions including precipitation, wind
speed, and cloud coverage.
Isotherm
 _______________________________________
 Connects points of the same temperature
o “iso” = _____________
o “therm” = ______________
Isobar
o Line drawn to connect _________________________________
o You can tell how fast the wind is blowing in an area by how
close the isobars are; __________________________________
o _____________________________________________________
 Remember lows usually mean clouds and precipitation
 Highs mean fair weather
Climate = ____________________________________________________
The Sun
 __________________________________________… it supplies the
energy for air and water to heat and move which causes winds
 _______________________________________________________…
but cause changing weather.
 Temperatures are closer to the equator because of the direction
of sunlight
 ________________________________________________________
o Northern hemisphere has summer when it is tilted towards
the sun… Southern hemisphere is on opposite seasons
o June 21 summer solstice – ______________________
o December 21 winter solstice – _______________________
o March 21 vernal (spring) equinox – _____________________
o September 22 autumnal (fall) equinox – _________________
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___________________________________
 Hills, mountains, valleys etc affect pressure systems and climate
 _________________________________________________________
_________________________________________________________
 _________________________________________________________
 Broad flat surfaces (_______________) have winds and air masses
converge and create _____________________________________
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